The following outline is provided as an overview of and topical guide to immunology:

Immunology Immunology is a branch of medicineImmunology for Medical Students, Roderick Nairn, Matthew Helbert, Mosby, 2007 and biology that covers the medical study of immune systems in humans, animals, plants and sapient species. In such we can see the ...

is the study of all aspects of the

immune system The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splint ...

in all

organism In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and ...

s. It deals with the physiological functioning of the immune system in states of both health and disease; malfunctions of the immune system in immunological disorders ( autoimmune diseases, hypersensitivities,

immune deficiency Immunodeficiency, also known as immunocompromisation, is a state in which the immune system's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that a ...

transplant rejection Transplant rejection occurs when transplanted tissue is rejected by the recipient's immune system, which destroys the transplanted tissue. Transplant rejection can be lessened by determining the molecular similitude between donor and recipient ...

); the physical, chemical and physiological characteristics of the components of the immune system

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called " test-tube experiments", these studies in biology ...

in situ ''In situ'' (; often not italicized in English) is a Latin phrase that translates literally to "on site" or "in position." It can mean "locally", "on site", "on the premises", or "in place" to describe where an event takes place and is used in ...

, and

in vivo Studies that are ''in vivo'' (Latin for "within the living"; often not italicized in English) are those in which the effects of various biological entities are tested on whole, living organisms or cells, usually animals, including humans, and ...

Essence of immunology

* Branch of

Biomedical science Biomedical sciences are a set of sciences applying portions of natural science or formal science, or both, to develop knowledge, interventions, or technology that are of use in healthcare or public health. Such disciplines as medical microbi ...

Immune system The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splint ...

Immunity Immunity may refer to: Medicine * Immunity (medical), resistance of an organism to infection or disease * ''Immunity'' (journal), a scientific journal published by Cell Press Biology * Immune system Engineering * Radiofrequence immunity desc ...

Branches of immunology

* Classical immunology * Clinical immunology * Computational immunology * Diagnostic immunology * Evolutionary immunology * Systems immunology * Immunomics * Immunoproteomics * Immunophysics *

Immunochemistry Immunochemistry is the study of the chemistry of the immune system. This involves the study of the properties, functions, interactions and production of the chemical components (antibodies/immunoglobulins, toxin, epitopes of proteins like CD4, a ...

* Ecoimmunology *

Immunopathology Immunopathology is a branch of medicine that deals with immune responses associated with disease. It includes the study of the pathology of an organism, organ system, or disease with respect to the immune system, immunity, and immune responses. In ...

* Nutritional immunology *

Psychoneuroimmunology Psychoneuroimmunology (PNI), also referred to as psychoendoneuroimmunology (PENI) or psychoneuroendocrinoimmunology (PNEI), is the study of the interaction between psychological processes and the nervous and immune systems of the human body. It is ...

* Reproductive immunology * Circadian immunology * Immunotoxicology * Palaeoimmunology * Tissue-based immunology :* Testicular immunology -

Testes A testicle or testis (plural testes) is the male reproductive gland or gonad in all bilaterians, including humans. It is homologous to the female ovary. The functions of the testes are to produce both sperm and androgens, primarily testoste ...

Immunodermatology Immunodermatology studies skin as an organ of immunity in health and disease. Several areas have special attention, such as photo-immunology (effects of UV light on skin defense), inflammatory diseases such as Hidradenitis suppurativa, allergic co ...

Skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different de ...

:* Intravascular immunology -

Blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the cir ...

:* Osteoimmunology -

Bone A bone is a rigid organ that constitutes part of the skeleton in most vertebrate animals. Bones protect the various other organs of the body, produce red and white blood cells, store minerals, provide structure and support for the body, ...

Mucosal immunology Mucosal immunology is the study of immune system responses that occur at mucosal membranes of the intestines, the urogenital tract, and the respiratory system. The mucous membranes are in constant contact with microorganisms, food, and inhaled ...

- Mucosal surfaces ::* Respiratory tract antimicrobial defense system - Respiratory tract :* Neuroimmunology -

Neuroimmune system The neuroimmune system is a system of structures and processes involving the biochemical and electrophysiological interactions between the nervous system and immune system which protect neurons from pathogens. It serves to protect neurons against ...

in the

Central nervous system The central nervous system (CNS) is the part of the nervous system consisting primarily of the brain and spinal cord. The CNS is so named because the brain integrates the received information and coordinates and influences the activity of all p ...

:* Ocularimmunology - Ocular immune system in the Eye :*

Cancer immunology Cancer immunology is an interdisciplinary branch of biology that is concerned with understanding the role of the immune system in the progression and development of cancer; the most well known application is cancer immunotherapy, which utilis ...

Immunooncology Cancer immunotherapy (sometimes called immuno-oncology) is the stimulation of the immune system to treat cancer, improving on the immune system's natural ability to fight the disease. It is an application of the fundamental research of cancer ...

Tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

History of immunology

History of immunology * Timeline of immunology

General immunological concepts

: :* Immunity against: ::*

Pathogen In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ ...

s ::** Pathogenic bacteria ::**

Virus A virus is a submicroscopic infectious agent that replicates only inside the living cells of an organism. Viruses infect all life forms, from animals and plants to microorganisms, including bacteria and archaea. Since Dmitri Ivanovsk ...

es ::**

Fungi A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from ...

::** Protozoa ::*

Parasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...

s ::*

Allergen An allergen is a type of antigen that produces an abnormally vigorous immune response in which the immune system fights off a perceived threat that would otherwise be harmless to the body. Such reactions are called allergies. In technical terms ...

s ::*

Self-protein Self-protein refers to all proteins endogenously produced by DNA-level transcription and translation within an organism of interest. This does not include proteins synthesized due to viral infection, but may include those synthesized by commensal ...

s :*

Autoimmunity In immunology, autoimmunity is the system of immune responses of an organism against its own healthy cells, tissues and other normal body constituents. Any disease resulting from this type of immune response is termed an "autoimmune disease". ...

Alloimmunity Alloimmunity (sometimes called isoimmunity) is an immune response to nonself antigens from members of the same species, which are called alloantigens or isoantigens. Two major types of alloantigens are blood group antigens and histocompatibility ...

Cross-reactivity Cross-reactivity, in a general sense, is the reactivity of an observed agent which initiates reactions outside the main reaction expected. This has implications for any kind of test or assay, including diagnostic tests in medicine, and can be a c ...

* Tolerance :*

Central tolerance In immunology, central tolerance (also known as negative selection) is the process of eliminating any ''developing'' T or B lymphocytes that are autoreactive, i.e. reactive to the body itself. Through elimination of autoreactive lymphocytes, to ...

:* Peripheral tolerance :* Clonal anergy :*

Clonal deletion In immunology, clonal deletion is the removal through apoptosis of B cells and T cells that have expressed receptors for self before developing into fully immunocompetent lymphocytes. This prevents recognition and destruction of self host cells, ...

:* Tolerance in pregnancy :* Immunodeficiency *

Antigen In immunology, an antigen (Ag) is a molecule or molecular structure or any foreign particulate matter or a pollen grain that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune respons ...

:* Antigenicity :*

Immunogen An immunogen is any substance that generates B-cell (humoral/antibody) and/or T-cell (cellular) adaptive immune responses upon exposure to a host organism. Immunogens that generate antibodies are called antigens ("antibody-generating"). Immunogen ...

:* Superantigen :*

Hapten In immunology, haptens are small molecules that elicit an immune response only when attached to a large carrier such as a protein; the carrier may be one that also does not elicit an immune response by itself (in general, only large molecules, i ...

Epitope An epitope, also known as antigenic determinant, is the part of an antigen that is recognized by the immune system, specifically by antibodies, B cells, or T cells. The epitope is the specific piece of the antigen to which an antibody binds. The p ...

::*

Linear Linearity is the property of a mathematical relationship ('' function'') that can be graphically represented as a straight line. Linearity is closely related to '' proportionality''. Examples in physics include rectilinear motion, the linear ...

::* Conformational ::*

Mimotope A mimotope is often a peptide, and mimics the structure of an epitope. Because of this property it causes an antibody response similar to the one elicited by the epitope. An antibody for a given epitope antigen will recognize a mimotope which mimics ...

Tumor antigen Tumor antigen is an antigenic substance produced in tumor cells, i.e., it triggers an immune response in the host. Tumor antigens are useful tumor markers in identifying tumor cells with diagnostic tests and are potential candidates for use in ...

Antigen-antibody interaction Antigen-antibody interaction, or antigen-antibody reaction, is a specific chemical interaction between antibodies produced by B cells of the white blood cells and antigens during immune reaction. The antigens and antibodies combine by a process call ...

* Immunogenetics :*

Affinity maturation In immunology, affinity maturation is the process by which TFH cell-activated B cells produce antibodies with increased affinity for antigen during the course of an immune response. With repeated exposures to the same antigen, a host will produc ...

::*

Somatic hypermutation Somatic hypermutation (or SHM) is a cellular mechanism by which the immune system adapts to the new foreign elements that confront it (e.g. microbes), as seen during class switching. A major component of the process of affinity maturation, SHM div ...

::*

Clonal selection In immunology, clonal selection theory explains the functions of cells of the immune system (lymphocytes) in response to specific antigens invading the body. The concept was introduced by Australian doctor Frank Macfarlane Burnet in 1957, in an ...

V(D)J recombination V(D)J recombination is the mechanism of somatic recombination that occurs only in developing lymphocytes during the early stages of T and B cell maturation. It results in the highly diverse repertoire of antibodies/immunoglobulins and T cell re ...

::*

Artemis complex The Artemis complex is a protein complex that functions in V(D)J recombination, the somatic recombination process which generates diversity in T cell receptors and immunoglobulins. Mutations in the Artemis complex results in hypersensitivity to DNA ...

::*

Recombination-activating gene The recombination-activating genes (RAGs) encode parts of a protein complex that plays important roles in the rearrangement and recombination of the genes encoding immunoglobulin and T cell receptor molecules. There are two recombination-activa ...

:::* RAG1 :::*

RAG2 Recombination activating gene 2 protein (also known as RAG-2) is a lymphocyte-specific protein encoded by RAG2 gene on human chromosome 11. Together with RAG1 protein, RAG2 forms a V(D)J recombinase, a protein complex required for the process of V( ...

::*

Recombination signal sequences Recombination signal sequences are conserved sequences of noncoding DNA that are recognized by the RAG1/RAG2 enzyme complex during V(D)J recombination in immature B cells and T cells. Recombination signal sequences guide the enzyme complex to the ...

Junctional diversity Junctional diversity describes the DNA sequence variations introduced by the improper joining of gene segments during the process of V(D)J recombination. This process of V(D)J recombination has vital roles for the vertebrate immune system, as it ...

Immunoglobulin class switching Immunoglobulin class switching, also known as isotype switching, isotypic commutation or class-switch recombination (CSR), is a biological mechanism that changes a B cell's production of immunoglobulin from one type to another, such as from the ...

:* Allelic exclusion :*

Polyclonal response Polyclonal B cell response is a natural mode of immune response exhibited by the adaptive immune system of mammals. It ensures that a single antigen is recognized and attacked through its overlapping parts, called epitopes, by multiple clones of ...

Phagocytosis Phagocytosis () is the process by which a cell uses its plasma membrane to engulf a large particle (≥ 0.5 μm), giving rise to an internal compartment called the phagosome. It is one type of endocytosis. A cell that performs phagocytosis is ...

Opsonin Opsonins are extracellular proteins that, when bound to substances or cells, induce phagocytes to phagocytose the substances or cells with the opsonins bound. Thus, opsonins act as tags to label things in the body that should be phagocytosed (i.e. ...

Intrinsic immunity Intrinsic immunity refers to a set of cellular-based anti-viral defense mechanisms, notably genetically encoded proteins which specifically target eukaryotic retroviruses. Unlike adaptive and innate immunity effectors, intrinsic immune proteins ...

Leukocyte extravasation Leukocyte extravasation (also commonly known as leukocyte adhesion cascade or diapedesis – the passage of cells through the intact vessel wall) is the movement of leukocytes out of the circulatory system and towards the site of tissue damage or ...

* Cross-presentation * Immune repertoire *

Original antigenic sin Original antigenic sin, also known as antigenic imprinting, the Hoskins effect, or immunological imprinting, is the propensity of the immune system to preferentially use immunological memory based on a previous infection when a second slightly di ...

Antigen presentation Antigen presentation is a vital immune process that is essential for T cell immune response triggering. Because T cells recognize only fragmented antigens displayed on cell surfaces, antigen processing must occur before the antigen fragment, n ...

Immunological synapse In immunology, an immunological synapse (or immune synapse) is the interface between an antigen-presenting cell or target cell and a lymphocyte such as a T/B cell or Natural Killer cell. The interface was originally named after the neuronal syna ...

Co-stimulation Co-stimulation is a secondary signal which immune cells rely on to activate an immune response in the presence of an antigen-presenting cell. In the case of T cells, two stimuli are required to fully activate their immune response. During the activa ...

Components of the immune system

Adaptive immune system

Adaptive immune system The adaptive immune system, also known as the acquired immune system, is a subsystem of the immune system that is composed of specialized, systemic cells and processes that eliminate pathogens or prevent their growth. The acquired immune system ...

:* Humoral immunity ::* Antibodies :::* Kinds of antibodies ::::* Monoclonal antibodies ::::* Polyclonal antibodies ::::*

Autoantibody An autoantibody is an antibody (a type of protein) produced by the immune system that is directed against one or more of the individual's own proteins. Many autoimmune diseases (notably lupus erythematosus) are associated with such antibodies. P ...

::::* Microantibody ::::*

Neutralizing antibody A neutralizing antibody (NAb) is an antibody that defends a cell from a pathogen or infectious particle by neutralizing any effect it has biologically. Neutralization renders the particle no longer infectious or pathogenic. Neutralizing antibod ...

:::* Classification ::::* Allotype ::::* Isotype ::::*

Idiotype In immunology, an idiotype is a shared characteristic between a group of immunoglobulin or T-cell receptor (TCR) molecules based upon the antigen binding specificity and therefore structure of their variable region. The variable region of antigen ...

:::* Functions ::::* Antibody opsonization ::::* Neutralisation :::* Regions ::::*

Paratope In immunology, a paratope, also known as an antigen-binding site, is the part of an antibody which recognizes and binds to an antigen. It is a small region at the tip of the antibody's antigen-binding fragment and contains parts of the antibody' ...

::::*

Complementarity-determining region Complementarity-determining regions (CDRs) are part of the variable chains in immunoglobulins (antibodies) and T cell receptors, generated by B-cells and T-cells respectively, where these molecules bind to their specific antigen. A set of CDRs co ...

(CDRs) ::::*

Hypervariable region A hypervariable region (HVR) is a location within nuclear DNA or the D-loop of mitochondrial DNA in which base pairs of nucleotides repeat (in the case of nuclear DNA) or have substitutions (in the case of mitochondrial DNA). Changes or repeat ...

::::* Framework region ::::*

Fab Region Fab or FAB may refer to: Commerce * Fab (brand), a frozen confectionery * Fab (website), an e-commerce design web site * The FAB Awards, a food and beverage award * FAB Link, a European electricity link * Flavoured alcoholic beverage or alcopo ...

::::*

Fc Region The fragment crystallizable region (Fc region) is the tail region of an antibody that interacts with cell surface receptors called Fc receptors and some proteins of the complement system. This property allows antibodies to activate the immune s ...

::* Polyclonal B cell response :*

Cell-mediated immunity Cell-mediated immunity or cellular immunity is an immune response that does not involve antibodies. Rather, cell-mediated immunity is the activation of phagocytes, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in ...

Innate immune system

Innate immune system :* Complement system ::*

Classical complement pathway The classical complement pathway is one of three pathways which activate the complement system, which is part of the immune system. The classical complement pathway is initiated by antigen-antibody complexes with the antibody isotypes IgG and ...

::*

Mannan-binding lectin pathway The lectin pathway or lectin complement pathway is a type of cascade reaction in the complement system, similar in structure to the classical complement pathway, in that, after activation, it proceeds through the action of C4 and C2 to produce acti ...

::* Alternate complement pathway ::*

Complement membrane attack complex The membrane attack complex (MAC) or terminal complement complex (TCC) is a complex of proteins typically formed on the surface of pathogen cell membranes as a result of the activation of the host's complement system, and as such is an effector ...

:* Surface barriers – Physical or chemical barriers that prevent infection (i.e.

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different de ...

tears Tears are a clear liquid secreted by the lacrimal glands (tear gland) found in the eyes of all land mammals. Tears are made up of water, electrolytes, proteins, lipids, and mucins that form layers on the surface of eyes. The different types of ...

mucus Mucus ( ) is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both serous and mucous cells. It ...

, saliva, Gastric acid, etc.) ::* Antimicrobial peptides ::*

Defensins Defensins are small cysteine-rich cationic proteins across cellular life, including vertebrate and invertebrate animals, plants, and fungi. They are host defense peptides, with members displaying either direct antimicrobial activity, immune sig ...

::*

Lysozyme Lysozyme (EC 3.2.1.17, muramidase, ''N''-acetylmuramide glycanhydrolase; systematic name peptidoglycan ''N''-acetylmuramoylhydrolase) is an antimicrobial enzyme produced by animals that forms part of the innate immune system. It is a glycoside ...

Inflammation Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...

::* Inflammatory reflex ::*

Inflammasome Inflammasomes are cytosolic multiprotein oligomers of the innate immune system responsible for the activation of inflammatory responses. Activation and assembly of the inflammasome promotes proteolytic cleavage, maturation and secretion of pro-in ...

::* Granuloma ::*

Acute-phase protein Acute-phase proteins (APPs) are a class of proteins whose concentrations in blood plasma either increase (positive acute-phase proteins) or decrease (negative acute-phase proteins) in response to inflammation. This response is called the ''acute-p ...

s :::*

Amyloid Amyloids are aggregates of proteins characterised by a fibrillar morphology of 7–13 nm in diameter, a beta sheet (β-sheet) secondary structure (known as cross-β) and ability to be stained by particular dyes, such as Congo red. In the huma ...

SAP Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant. Sap is distinct from latex, resin, or cell sap; it is a separ ...

* SAA :::* Positive *

Alpha 1-antichymotrypsin Alpha 1-antichymotrypsin (symbol α1AC, A1AC, or a1ACT) is an alpha globulin glycoprotein that is a member of the serpin superfamily. In humans, it is encoded by the ''SERPINA3'' gene. Function Alpha 1-antichymotrypsin inhibits the activity o ...

* Alpha 1-antitrypsin *

Alpha 2-macroglobulin α2-Macroglobulin (α2M), or alpha-2-macroglobulin, is a large (720 KDa) plasma protein found in the blood. It is mainly produced by the liver, and also locally synthesized by macrophages, fibroblasts, and adrenocortical cells. In humans it is e ...

C-reactive protein C-reactive protein (CRP) is an annular (ring-shaped) pentameric protein found in blood plasma, whose circulating concentrations rise in response to inflammation. It is an acute-phase protein of hepatic origin that increases following interleukin- ...

Ceruloplasmin Ceruloplasmin (or caeruloplasmin) is a ferroxidase enzyme that in humans is encoded by the ''CP'' gene. Ceruloplasmin is the major copper-carrying protein in the blood, and in addition plays a role in iron metabolism. It was first described in 1 ...

* C3 *

Ferritin Ferritin is a universal intracellular protein that stores iron and releases it in a controlled fashion. The protein is produced by almost all living organisms, including archaea, bacteria, algae, higher plants, and animals. It is the primary ' ...

* Fibrin *

Haptoglobin Haptoglobin (abbreviated as Hp) is the protein that in humans is encoded by the ''HP'' gene. In blood plasma, haptoglobin binds with high affinity to ''free'' hemoglobin released from erythrocytes, and thereby inhibits its deleterious oxidative ...

Hemopexin Hemopexin (or haemopexin; Hpx; Hx), also known as beta-1B-glycoprotein, is a glycoprotein that in humans is encoded by the ''HPX'' gene and belongs to the hemopexin family of proteins. Hemopexin is the plasma protein with the highest binding aff ...

Orosomucoid Orosomucoid (ORM) or alpha-1-acid glycoprotein (''α1AGp'', ''AGP'' or ''AAG'') is an acute phase protein found in plasma. It is an alpha-globulin glycoprotein and is modulated by two polymorphic genes. It is synthesized primarily in hepatoc ...

:::* Negative *

Serum albumin Serum albumin, often referred to simply as blood albumin, is an albumin (a type of globular protein) found in vertebrate blood. Human serum albumin is encoded by the ''ALB'' gene. Other mammalian forms, such as bovine serum albumin, are chemica ...

Transferrin Transferrins are glycoproteins found in vertebrates which bind to and consequently mediate the transport of iron (Fe) through blood plasma. They are produced in the liver and contain binding sites for two Fe3+ ions. Human transferrin is encode ...

Organs of the immune system

Lymphatic system

Primary lymphoid organs

Primary lymphoid organs :*

Thymus The thymus is a specialized primary lymphoid organ of the immune system. Within the thymus, thymus cell lymphocytes or ''T cells'' mature. T cells are critical to the adaptive immune system, where the body adapts to specific foreign invaders. ...

- Site of

T cell A T cell is a type of lymphocyte. T cells are one of the important white blood cells of the immune system and play a central role in the adaptive immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell r ...

maturation :* Bone marrow - Site of

haematopoiesis Haematopoiesis (, from Greek , 'blood' and 'to make'; also hematopoiesis in American English; sometimes also h(a)emopoiesis) is the formation of blood cellular components. All cellular blood components are derived from haematopoietic stem cell ...

and B cell maturation

Secondary lymphoid organs

Secondary lymphoid organs :*

Spleen The spleen is an organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter. The word spleen comes .

:**

White pulp White pulp is a histological designation for regions of the spleen (named because it appears whiter than the surrounding red pulp on gross section), that encompasses approximately 25% of splenic tissue. White pulp consists entirely of lymphoid ti ...

:** Red pulp :**

Marginal zone The marginal zone is the region at the interface between the non-lymphoid red pulp and the lymphoid white-pulp of the spleen. (Some sources consider it to be the part of red pulp which borders on the white pulp, while other sources consider it to ...

:* Lymph nodes :*

Mucosa-associated lymphoid tissue The mucosa-associated lymphoid tissue (MALT), also called mucosa-associated lymphatic tissue, is a diffuse system of small concentrations of lymphoid tissue found in various submucosal membrane sites of the body, such as the gastrointestinal tr ...

::*

Gut-associated lymphoid tissue Gut-associated lymphoid tissue (GALT) is a component of the mucosa-associated lymphoid tissue (MALT) which works in the immune system to protect the body from invasion in the gut. Owing to its physiological function in food absorption, the mucosa ...

::* Bronchus-associated lymphoid tissue

Cells of the immune system

White blood cells White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...

Myeloid cells

: : :* Granulocytes :**

Neutrophil Neutrophils (also known as neutrocytes or heterophils) are the most abundant type of granulocytes and make up 40% to 70% of all white blood cells in humans. They form an essential part of the innate immune system, with their functions varying ...

s :**

Eosinophil Eosinophils, sometimes called eosinophiles or, less commonly, acidophils, are a variety of white blood cells (WBCs) and one of the immune system components responsible for combating multicellular parasites and certain infections in vertebrates. A ...

s :**

Basophil Basophils are a type of white blood cell. Basophils are the least common type of granulocyte, representing about 0.5% to 1% of circulating white blood cells. However, they are the largest type of granulocyte. They are responsible for inflammator ...

s :**

Mast cells A mast cell (also known as a mastocyte or a labrocyte) is a resident cell of connective tissue that contains many granules rich in histamine and heparin. Specifically, it is a type of granulocyte derived from the myeloid stem cell that is a ...

Monocyte Monocytes are a type of leukocyte or white blood cell. They are the largest type of leukocyte in blood and can differentiate into macrophages and conventional dendritic cells. As a part of the vertebrate innate immune system monocytes also ...

s :* Macrophages ::*

Histiocyte A histiocyte is a vertebrate cell that is part of the mononuclear phagocyte system (also known as the reticuloendothelial system or lymphoreticular system). The mononuclear phagocytic system is part of the organism's immune system. The histiocyt ...

s (Tissue resident macrophages) :::*

Adipose tissue macrophages Adipose tissue macrophages (abbr. ATMs) comprise tissue resident macrophages present in adipose tissue. Adipose tissue apart from adipocytes is composed of the stromal vascular fraction (SVF) of cells including preadipocytes, fibroblasts, vascular ...

:::*

Kupffer cell Kupffer cells, also known as stellate macrophages and Kupffer–Browicz cells, are specialized cells localized in the liver within the lumen of the liver sinusoids and are adhesive to their endothelial cells which make up the blood vessel walls. Ku ...

Liver The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it ...

:::*

Alveolar macrophage An alveolar macrophage, pulmonary macrophage, (or dust cell) is a type of macrophage, a professional phagocyte, found in the airways and at the level of the alveoli in the lungs, but separated from their walls. Activity of the alveolar macropha ...

(Dust cell) - Lung :::*

Langerhans cell A Langerhans cell (LC) is a tissue-resident macrophage of the skin. These cells contain organelles called Birbeck granules. They are present in all layers of the epidermis and are most prominent in the stratum spinosum. They also occur in the ...

:::* Dermal macrophage - Dermis :::* Microglia - CNS :::* Perivascular macrophage :::* Meningeal macrophage - Meninges :::* Hofbauer cell -

Placenta The placenta is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas and waste exchange between the physically separate mate ...

:::*

Osteoclasts An osteoclast () is a type of bone cell that breaks down bone tissue. This function is critical in the maintenance, repair, and remodeling of bones of the vertebral skeleton. The osteoclast disassembles and digests the composite of hydrated prote ...

:::* Bone marrow macrophage - Bone marrow :::* Marginal zone macrophage -

Spleen The spleen is an organ found in almost all vertebrates. Similar in structure to a large lymph node, it acts primarily as a blood filter. The word spleen comes .

:::* Metallophilic macrophage - Spleen :::* Red pulp macrophage - Splenic red pulp :::*

Tingible body macrophage A tingible body macrophage (TBMs) is a type of macrophage predominantly found in germinal centers, containing many phagocytosis, phagocytized, apoptosis, apoptotic cells in various states of degradation, referred to as tingible bodies (tingible me ...

(White pulp macrophage) - Splenic white pulp ::*

Giant cell A giant cell (also known as multinucleated giant cell, or multinucleate giant cell) is a mass formed by the union of several distinct cells (usually histiocytes), often forming a granuloma. Although there is typically a focus on the pathologica ...

s :::*

Foreign-body giant cell A foreign-body giant cell is a collection of fused macrophages (giant cell) which are generated in response to the presence of a large foreign body. This is particularly evident with catheters, parasites, or biomaterials that are inserted into th ...

:::* Langhans giant cell :::* Touton giant cells ::*

Epithelioid cell According to a common point of view epithelioid cells (also called epithelioid histiocytes) are derivatives of activated macrophages resembling epithelial cells. Structure and function Structurally, epithelioid cells (when examined by light m ...

s ::* Bone marrow-derived macrophages - Generated

:* Dendritic Cells ::*

Conventional Dendritic Cell Dendritic cells (DCs) are antigen-presenting cells (also known as ''accessory cells'') of the mammalian immune system. Their main function is to process antigen material and present it on the cell surface to the T cells of the immune system. The ...

s ::*

Plasmacytoid dendritic cell Plasmacytoid dendritic cells (pDCs) are a rare type of immune cell that are known to secrete large quantities of type 1 interferon (IFNs) in response to a viral infection. They circulate in the blood and are found in peripheral lymphoid organs. T ...

Lymphoid cells

Lymphoid cells :* B cells :** Plasma B cells :**

Memory B cell In immunology, a memory B cell (MBC) is a type of B lymphocyte that forms part of the adaptive immune system. These cells develop within germinal centers of the secondary lymphoid organs. Memory B cells circulate in the blood stream in a quiesc ...

s :**

B-1 cell B1 cells are a sub-class of B cell lymphocytes that are involved in the humoral immune response. They are not part of the adaptive immune system, as they have no memory, but otherwise, B1 cells perform many of the same roles as other B cells: maki ...

s :** B-2 cells (the conventional B cells most texts refer to) :** Marginal-zone B cells :**

Follicular B cell Within the immune system, Follicular B cells (FO B cells) are a type of B cell that reside in primary and secondary lymphoid follicles (containing germinal centers) of secondary and tertiary lymphoid organs, including spleen and lymph nodes. Antibo ...

s :*

s :** Naive T cells :** Helper T cells - Commonly termed CD4+ T cells :***

Th1 cell The T helper cells (Th cells), also known as CD4+ cells or CD4-positive cells, are a type of T cell that play an important role in the adaptive immune system. They aid the activity of other immune cells by releasing cytokines. They are consider ...

s :*** Th2 cells :*** Th3 cells :*** Th17 cells :*** T_FH cells - Follicular helper T cells :** Cytotoxic T cells - Commonly termed CD8+ T cells :**

Memory T cells Memory T cells are a subset of T lymphocytes that might have some of the same functions as memory B cells. Their lineage is unclear. Function Antigen-specific memory T cells specific to viruses or other microbial molecules can be found in both ...

:**

Regulatory T cell The regulatory T cells (Tregs or Treg cells), formerly known as suppressor T cells, are a subpopulation of T cells that modulate the immune system, maintain tolerance to self-antigens, and prevent autoimmune disease. Treg cells are immunosu ...

s :**

Natural Killer T cell Natural killer T (NKT) cells are a heterogeneous group of T cells that share properties of both T cells and natural killer cells. Many of these cells recognize the non-polymorphic CD1d molecule, an antigen-presenting molecule that binds self an ...

s (NKT cells) :** γδ T cells :** Mucosal associated invariant T cells :*

Innate lymphoid cell Innate lymphoid cells (ILCs) are the most recently discovered family of innate immune cells, derived from common lymphoid progenitors (CLPs). In response to pathogenic tissue damage, ILCs contribute to immunity via the secretion of signalling mo ...

s (ILC) :** Group 1 ILC :*** Natural killer cells (NK cells) :** Group 2 ILC :*** Nuocyte :** Group 3 ILC :*** Lymphoid Tissue inducer cells (LTi cells)

Others

:(Non-hematopoietic cells with immune functions) :*

Stromal cell Stromal cells, or mesenchymal stromal cells, are differentiating cells found in abundance within bone marrow but can also be seen all around the body. Stromal cells can become connective tissue cells of any organ, for example in the uterine mucosa ...

s ::*

Lymph node stromal cell Lymph node stromal cells are essential to the structure and function of the lymph node whose functions include: creating an internal tissue scaffold for the support of hematopoietic cells; the release of small molecule chemical messengers that facil ...

s ::*

Follicular dendritic cell Follicular dendritic cells (FDC) are cells of the immune system found in primary and secondary lymph follicles (lymph nodes) of the B cell areas of the lymphoid tissue. Unlike dendritic cells (DC), FDCs are not derived from the bone-marrow hema ...

s :* Epithelial cells :*

Pericyte Pericytes (previously known as Rouget cells) are multi-functional mural cells of the microcirculation that wrap around the endothelial cells that line the capillaries throughout the body. Pericytes are embedded in the basement membrane of blood ca ...

s :*

Microfold cell Microfold cells (or M cells) are found in the gut-associated lymphoid tissue (GALT) of the Peyer's patches in the small intestine, and in the mucosa-associated lymphoid tissue (MALT) of other parts of the gastrointestinal tract. These cells are kn ...

s (M cells)

Hematopoiesis

: : :*

Lymphopoiesis Lymphopoiesis (lĭm'fō-poi-ē'sĭs) (or lymphocytopoiesis) is the generation of lymphocytes, which are one of the five types of white blood cells (WBCs). It is more formally known as lymphoid hematopoiesis. Disruption in lymphopoiesis can lead t ...

::*

Lymphoblast __NOTOC__ A lymphoblast is a modified naive lymphocyte with altered cell morphology. It occurs when the lymphocyte is activated by an antigen (from antigen-presenting cells) and increased in volume by nucleus and cytoplasm growth as well as new mRN ...

::* Prolymphocyte :::* T cell development ::::*

Thymocyte A Thymocyte is an immune cell present in the thymus, before it undergoes transformation into a T cell. Thymocytes are produced as stem cells in the bone marrow and reach the thymus via the blood. Thymopoiesis describes the process which turns thymo ...

:::* B cell development ::::* Pre-pro-B cell ::::* Early pro-B cell ::::* Late pro-B cell ::::* Large pre-B cell ::::* Small pre-B cell ::::* Immature B cell :*

Myelopoiesis In hematology, myelopoiesis in the broadest sense of the term is the production of bone marrow and of all cells that arise from it, namely, all blood cells. In a narrower sense, myelopoiesis also refers specifically to the regulated formation of my ...

::* Common myeloid progenitor (CFU-GEMM) :::* Granulocyte-macrophage progenitor (CFU-GM) ::::*

Granulopoiesis Granulopoiesis (or granulocytopoiesis) is a part of haematopoiesis, that leads to the production of granulocytes. A granulocyte, also referred to as a polymorphonuclear leukocyte (PMN), is a type of white blood cell that has multi lobed nuclei, u ...

:::::* Myeloblast (CFU-G) :::::*

Promyelocyte A promyelocyte (or progranulocyte) is a granulocyte precursor, developing from the myeloblast and developing into the myelocyte. Promyelocytes measure 12-20 microns in diameter. The nucleus of a promyelocyte is approximately the same size as a mye ...

:::::* Myelocyte :::::*

Metamyelocyte A metamyelocyte is a cell undergoing granulopoiesis, derived from a myelocyte, and leading to a band cell. It is characterized by the appearance of a bent nucleus, cytoplasmic granules, and the absence of visible nucleoli. (If the nucleus is n ...

:::::*

Band cell A band cell (also called band neutrophil, band form or stab cell) is a cell undergoing granulopoiesis, derived from a metamyelocyte, and leading to a mature granulocyte. It is characterized by having a curved but not lobular nucleus. The term ...

::::* Monocytopoiesis :::::*

Monoblast Monoblasts are the committed progenitor cells that differentiated from a committed macrophage or dendritic cell precursor (MDP) in the process of hematopoiesis. They are the first developmental stage in the monocyte series leading to a macrophage ...

(CFU-M) ::::::* CFU-DL - Dendritic cell /

precursor :::::* Promonocyte :::* CFU-Baso (Basophil precursor) :::* CFU-Eos (Eosinophil precursor) :::* Megakaryocyte-erythroid progenitor cell (MEP) ::::* Megakaryocytopoiesis :::::*

CFU-Meg CFU-Meg is a colony forming unit. Haematopoiesis in the bone marrow starts off from a haematopoietic stem cell (HSC) and this can differentiate into the myeloid and lymphoid cell lineages. In order to eventually produce a megakaryocyte, the haemato ...

:::::* Megakaryoblast :::::* Promegakaryocyte :::::*

Megakaryocyte A megakaryocyte (''mega-'' + '' karyo-'' + '' -cyte'', "large-nucleus cell") is a large bone marrow cell with a lobated nucleus responsible for the production of blood thrombocytes (platelets), which are necessary for normal blood clotting. In ...

:::::*

Thrombopoiesis Thrombopoiesis is the formation of thrombocytes (blood platelets) in the bone marrow. Thrombopoietin is the main regulator of thrombopoiesis. Thrombopoietin affects most aspects of the production of platelets. This includes self-renewal and expan ...

::::::*

Thrombocyte Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby in ...

(

Platelet Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby i ...

s) ::::*

Erythropoiesis Erythropoiesis (from Greek 'erythro' meaning "red" and 'poiesis' "to make") is the process which produces red blood cells (erythrocytes), which is the development from erythropoietic stem cell to mature red blood cell. It is stimulated by decrea ...

:::::*

Proerythroblast A proerythroblast (or rubriblast, or pronormoblast) is the earliest of four stages in development of the normoblast. In histology, it is very difficult to distinguish it from the other "-blast" cells (lymphoblast, myeloblast, monoblast, and me ...

:::::*

Normoblast A nucleated red blood cell (NRBC), also known by several other names, is a red blood cell that contains a cell nucleus. Almost all vertebrate organisms have hemoglobin-containing cells in their blood, and with the exception of mammals, all of the ...

:::::*

Reticulocyte Reticulocytes are immature red blood cells (RBCs). In the process of erythropoiesis (red blood cell formation), reticulocytes develop and mature in the bone marrow and then circulate for about a day in the blood stream before developing into ma ...

:::* CFU-Mast ::::* Mast cell precursors

Molecules of the immune system

Immune receptors

Antigen receptors

:* B cells ::* Antigen receptor -

B cell receptor The B cell receptor (BCR) is a transmembrane protein on the surface of a B cell. A B cell receptor is composed of a membrane-bound immunoglobulin molecule and a signal transduction moiety. The former forms a type 1 transmembrane receptor protein, ...

(BCR) ::* Subunits- Immunoglobulin heavy chain /

Immunoglobulin light chain ] The immunoglobulin light chain is the small Peptide, polypeptide subunit of an antibody (immunoglobulin). A typical antibody is composed of two immunoglobulin (Ig) heavy chains and two Ig light chains. In humans There are two types of light ...

::* Co-receptors :::* Stimulatory ::::*

CD21 Complement receptor type 2 (CR2), also known as complement C3d receptor, Epstein-Barr virus receptor, and CD21 (cluster of differentiation 21), is a protein that in humans is encoded by the CR2 gene. CR2 is involved in the complement system. It ...

::::* CD19 ::::* CD81 :::* Inhibitory ::::* CD22 ::* Accessory molecule (

CD79 Introduction CD79 ( Cluster of Differentiation 79) is a transmembrane protein that forms a complex with the B-cell receptor (BCR) and generates a signal following recognition of antigen by the BCR. CD79 is composed of two distinct chains call ...

) :::* Ig-α (CD79A) :::* Ig-β (CD79B) :*

s ::* Antigen receptor -

T cell receptor The T-cell receptor (TCR) is a protein complex found on the surface of T cells, or T lymphocytes, that is responsible for recognizing fragments of antigen as peptides bound to major histocompatibility complex (MHC) molecules. The binding ...

(TCR) :::* Subunits - TRA@ / TRB@ / TRD@ / TRG@ ::* Co-receptors :::*

CD8 CD8 (cluster of differentiation 8) is a transmembrane glycoprotein that serves as a co-receptor for the T-cell receptor (TCR). Along with the TCR, the CD8 co-receptor plays a role in T cell signaling and aiding with cytotoxic T cell-antigen int ...

( CD8α / CD8β) :::* CD4 ::* Accessory molecules :::* CD3 ::::* Subunits - one CD3γ / one CD3δ / two CD3ε :::* ζ-chain (CD247, CD3ζ, TCRζ)

Pattern recognition receptors (PRRs)

Pattern recognition receptor Pattern recognition receptors (PRRs) play a crucial role in the proper function of the innate immune system. PRRs are germline-encoded host sensors, which detect molecules typical for the pathogens. They are proteins expressed, mainly, by cells of ...

:* Membrane-bound PRRs ::*

Toll-like receptor Toll-like receptors (TLRs) are a class of proteins that play a key role in the innate immune system. They are single-pass membrane-spanning receptors usually expressed on sentinel cells such as macrophages and dendritic cells, that recognize ...

s (TLRs) * TLR1 *

TLR2 Toll-like receptor 2 also known as TLR2 is a protein that in humans is encoded by the ''TLR2'' gene. TLR2 has also been designated as CD282 (cluster of differentiation 282). TLR2 is one of the toll-like receptors and plays a role in the immune sys ...

TLR3 Toll-like receptor 3 (TLR3) also known as CD283 (cluster of differentiation 283) is a protein that in humans is encoded by the ''TLR3'' gene. TLR3 is a member of the toll-like receptor family of pattern recognition receptors of the innate immune ...

TLR4 Toll-like receptor 4 is a protein that in humans is encoded by the ''TLR4'' gene. TLR4 is a transmembrane protein, member of the toll-like receptor family, which belongs to the pattern recognition receptor (PRR) family. Its activation leads to an ...

* TLR5 *

TLR6 Toll-like receptor 6 is a protein that in humans is encoded by the ''TLR6'' gene. TLR6 is a transmembrane protein, member of toll-like receptor family, which belongs to the pattern recognition receptor (PRR) family. TLR6 acts in a heterodimer form ...

* TLR7 * TLR8 *

TLR9 Toll-like receptor 9 is a protein that in humans is encoded by the ''TLR9'' gene. TLR9 has also been designated as CD289 (cluster of differentiation 289). It is a member of the toll-like receptor (TLR) family. TLR9 is an important receptor expresse ...

TLR10 Toll-like receptor 10 is a protein that in humans is encoded by the ''TLR10'' gene. TLR10 has also been designated as CD290 ( cluster of differentiation 290). TLR10 has not been extensively studied because it is a pseudogene in mice, though all ot ...

TLR11 Toll-like receptor 11 (TLR11) is a protein that in mice and rats is encoded by the gene ''TLR11'', whereas in humans it is represented by a pseudogene. TLR11 belongs to the toll-like receptor (TLR) family and the interleukin-1 receptor/toll-like r ...

TLR12 Toll-like receptor 1 (TIL) is a member of the toll-like receptor family (TLR) of pattern recognition receptors of the innate immune system. TIL recognizes pathogen-associated molecular pattern with a specificity for gram-positive bacteria. TIL h ...

* TLR13 ::*

C-type lectin receptor Pattern recognition receptors (PRRs) play a crucial role in the proper function of the innate immune system. PRRs are germline-encoded host sensors, which detect molecules typical for the pathogens. They are proteins expressed, mainly, by cells of ...

s (CLRs) ::: :::* Group 1 CLRs - Mannose receptors * MRC1 * MRC2 * DEC205 (CD205) :::* Group 2 CLRs - Asialoglycoprotein receptor family *

DC-SIGN DC-SIGN (Dendritic Cell-Specific Intercellular adhesion molecule-3-Grabbing Non-integrin) also known as CD209 ( Cluster of Differentiation 209) is a protein which in humans is encoded by the ''CD209'' gene. DC-SIGN is a C-type lectin receptor pr ...

(CD209) *

Langerin Langerin (CD207) is a type II transmembrane protein which is encoded by the ''CD207'' gene in humans. It was discovered by scientists Sem Saeland and Jenny Valladeau as a main part of Birbeck granules. Langerin is C-type lectin receptor on Langer ...

(CD207) * CLEC10A (CD301, MGL) * CLEC5A (MDL1) ::::* Dectin 1 subfamily * Dectin 1 (CLEC7A) * MICL (CLEC12A) * CLEC2 * DNGR1 (CLEC9A) ::::* DCIR subfamily * Dectin 2 (CLEC6A) * BDCA2 (CD303) * Mincle (CLEC4E) * DCIR (CLEC4A) ::* Scavenger receptors :::* Class A - Trimers * MSR1 (SCARA1) * MARCO (SCARA2) * SCARA3 * SCARA4 (COLEC12) * SCARA5 :::* Class B - Two transmembrane domains * SCARB1 *

SCARB2 Lysosomal integral membrane protein 2 (LIMP-2) is a protein that in humans is encoded by the ''SCARB2'' gene. LIMP-2 is expressed in brain, heart, liver, lung and kidney, mainly in the membrane of lysosome organelles; however, in cardiac muscle, LI ...

CD36 CD36 (cluster of differentiation 36), also known as platelet glycoprotein 4, fatty acid translocase (FAT), scavenger receptor class B member 3 (SCARB3), and glycoproteins 88 (GP88), IIIb (GPIIIB), or IV (GPIV) is a protein that in humans is enco ...

(SCARB3) :::* Others * CD68 * LOX-1 ::* Formyl peptide receptors (FPRs) *

FPR1 Formyl peptide receptor 1 (FPR1, FPR1 receptor, fMet-Leu-Phe receptor 1, FMLP receptor 1, or N-formylmethionyl-leucyl-phenylalanine receptor 1) is a cell surface receptor protein that in humans is encoded by the ''formyl peptide receptor 1'' (''F ...

FPR2 N-formyl peptide receptor 2 (FPR2) is a G-protein coupled receptor (GPCR) located on the surface of many cell types of various animal species. The human receptor protein is encoded by the ''FPR2'' gene and is activated to regulate cell function ...

* FPR3 :* Cytoplasmic PRRs ::*

NOD-like receptor The nucleotide-binding oligomerization domain-like receptors, or NOD-like receptors (NLRs) (also known as nucleotide-binding leucine-rich repeat receptors), are intracellular sensors of pathogen-associated molecular patterns (PAMPs) that enter the ...

s (NLRs) :::* NLRA (A for acidic transactivating domain) ::::*

CIITA CIITA is a human gene which encodes a protein called the class II, major histocompatibility complex, transactivator. Mutations in this gene are responsible for the bare lymphocyte syndrome in which the immune system is severely compromised and c ...

:::* NLRB (B for BIR, or Inhibitor of apoptosis domain) ::::* NAIP :::* NLRC (C for

CARD domain Caspase recruitment domains, or caspase activation and recruitment domains (CARDs), are interaction motifs found in a wide array of proteins, typically those involved in processes relating to inflammation and apoptosis. These domains mediate th ...

) *

NOD1 Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) is a protein receptor that in humans is encoded by the ''NOD1'' gene. It recognizes bacterial molecules and stimulates an immune reaction . NOD1 protein contains a caspase recr ...

NOD2 Nucleotide-binding oligomerization domain-containing protein 2 (NOD2), also known as caspase recruitment domain-containing protein 15 (CARD15) or inflammatory bowel disease protein 1 (IBD1), is a protein that in humans is encoded by the ''NOD2'' g ...

* NLRC3 * NLRC4 (IPAF) * NLRC5 :::* NLRP (P for Pyrin domain) *

NLRP1 NLRP1 encodes NACHT, LRR, FIIND, CARD domain and PYD domains-containing protein 1 in humans. NLRP1 was the first protein shown to form an inflammasome. Material was copied from this source, which is available under Creative Commons Attribution 4. ...

* NLRP2 *

NLRP3 NLR family pyrin domain containing 3 (NLRP3) (previously known as NACHT, LRR and PYD domains-containing protein 3 ALP3and cryopyrin), is a protein that in humans is encoded by the ''NLRP3'' gene located on the long arm of chromosome 1. NLRP3 is ...

* NLRP4 * NLRP5 *

NLRP6 NLRP6, short for NOD-like receptor family pyrin domain containing 6, is an intracellular protein that plays a role in the immune system. It is also known as NALP6, PYPAF5, PAN3, and CLR11.4, and is one of 14 pyrin domain containing members of the ...

* NLRP7 * NLRP8 * NLRP9 *

NLRP10 NLRP10, short for NOD-like receptor family pyrin domain containing 10, is an intracellular protein of mammals that functions in apoptosis and the immune system. It is also known as NALP10, NOD8, PAN5, Pynod, and CLR11.1, and is one of 14 pyrin d ...

* NLRP11 *

NLRP12 NACHT, LRR and PYD domains-containing protein 12 is a protein that in humans is encoded by the ''NLRP12'' gene. NALPs are cytoplasmic proteins that form a subfamily within the larger CATERPILLER protein family. Most short NALPs, such as NALP12, ...

* NLRP13 * NLRP14 :::* NLRX ::::*

NLRX1 NLRX1 or NLR family member X1, short for ''nucleotide-binding oligomerization domain, leucine rich repeat containing X1'' is a protein that in humans is encoded by the ''NLRX1'' gene. It is also known as ''NOD-like receptor X1'', ''NLR family, X1' ...

::*

RIG-I-like receptor RIG-like receptors (retinoic acid-inducible gene-I-like receptors, RLRs) are a type of intracellular pattern recognition receptor involved in the recognition of viruses by the innate immune system. RIG-I (retinoic-acid inducible gene or DDX58) is ...

s (RLRs) - Intracellular sensors of viral replication by direct interaction with dsRNA *

RIG-I RIG-I (retinoic acid-inducible gene I) is a cytosolic pattern recognition receptor (PRR) responsible for the type-1 interferon (IFN1) response. RIG-I is an essential molecule in the innate immune system for recognizing cells that have been infect ...

MDA5 MDA5 (melanoma differentiation-associated protein 5) is a RIG-I-like receptor dsRNA helicase enzyme that is encoded by the ''IFIH1'' gene in humans. MDA5 is part of the RIG-I-like receptor (RLR) family, which also includes RIG-I and LGP2, and ...

* LGP2 :* Secreted PRRs ::* Complement system (see complement proteins section) ::*

Collectin Collectins (collagen-containing C-type lectins) are a part of the innate immune system. They form a family of collagenous Ca2+-dependent defense lectins, which are found in animals. Collectins are soluble pattern recognition receptors (PRRs). Their ...

s *

Mannan-binding lectin Mannose-binding lectin (MBL), also called mannan-binding lectin or mannan-binding protein (MBP), is a lectin that is instrumental in innate immunity as an opsonin and via the lectin pathway. Structure MBL has an oligomeric structure (400-700 kDa) ...

(MBL) *

Surfactant protein A Surfactant protein A is an innate immune system collectin. It is water-soluble and has collagen-like domains similar to SP-D. It is part of the innate immune system and is used to opsonize bacterial cells in the alveoli marking them for phagocyt ...

(SP-A) *

Surfactant protein D Surfactant protein D, also known as SP-D, is a lung surfactant protein part of the collagenous family of proteins called collectin. In humans, SP-D is encoded by the ''SFTPD'' gene and is part of the innate immune system. Each SP-D subunit is com ...

(SP-D) * CL-L1 * CL-P1 * CL-K1 ::* Peptidoglycan recognition proteins (PGRPs) * PGLYRP1 * PGLYRP2 * PGLYRP3 * PGLYRP4 ::*

Ficolin Ficolins are pattern recognition receptors that bind to acetyl groups present in the carbohydrates of bacterial surfaces and mediate activation of the lectin pathway of the complement cascade. Structure Ficolins (Fi+Col+Lin) are a group of olig ...

s * FCN1 * FCN2 * FCN3

Complement receptors

Complement receptor A complement receptor is a membrane-bound receptor belonging to the complement system, which is part of the innate immune system. Complement receptors bind effector protein fragments that are produced in response to antigen-antibody complexes or ...

:* CR1 (CD35) :* CR2 (CD21) :* CR3 - Heterodimer:

CD11b Integrin alpha M (ITGAM) is one protein subunit that forms heterodimeric integrin alpha-M beta-2 (αMβ2) molecule, also known as ''macrophage-1 antigen'' (Mac-1) or '' complement receptor 3'' (CR3). ITGAM is also known as CR3A, and cluster of dif ...

/ CD18 :* CR4 - Heterodimer:

CD11c CD11c, also known as Integrin, alpha X (complement component 3 receptor 4 subunit) (ITGAX), is a gene that encodes for CD11c . CD11c is an integrin alpha X chain protein. Integrins are heterodimeric integral membrane proteins composed of an alph ...

/ CD18 :* CRIg (Complement receptor of the immunoglobulin family) :* Anaphylatoxin receptors ::*

C3a receptor The C3a receptor also known as complement component 3a receptor 1 (C3AR1) is a G protein-coupled receptor protein involved in the complement system. The receptor binds to complement component C3a, although there is limited evidence that this rec ...

::*

C5a receptor The C5a receptor also known as complement component 5a receptor 1 (C5AR1) or CD88 (Cluster of Differentiation 88) is a G protein-coupled receptor for C5a. It functions as a complement receptor. C5a receptor modulates inflammatory responses, ob ...

(CD88) ::* C5AR2

Fc receptors

Fc receptor :* Fc-gamma receptors (FcγR) ::*

FcγRI CD64 (Cluster of Differentiation 64) is a type of integral membrane glycoprotein known as an Fc receptor that binds monomeric IgG-type antibodies with high affinity. It is more commonly known as Fc-gamma receptor 1 (FcγRI). After binding I ...

(CD64) ::* FcγRIIA (CD32A) ::* FcγRIIB (CD32B) ::*

FcγRIIIA Low affinity immunoglobulin gamma Fc region receptor III-A is a protein that in humans is encoded by the ''FCGR3A'' gene. It is also known as CD16a as it is part of the cluster of differentiation The cluster of differentiation (also known as clus ...

(CD16a) ::*

FcγRIIIB FCGR3B (Fc fragment of IgG, low affinity IIIb, receptor), also known as CD16b (Cluster of Differentiation 16b), is a human gene. Clinical relevance Mutations and copy-number variations in this gene have been associated to clinical cases of glomeru ...

(CD16b) ::* FcγRT (Neonatal Fc receptor) :* Fc-alpha receptors (FcαR) ::* FcαRI (CD89, FCAR) ::* Fcα/μR :* Fc-epsilon receptors (FcεR) ::*

FcεRI The high-affinity IgE receptor, also known as FcεRI, or Fc epsilon RI, is the high- affinity receptor for the Fc region of immunoglobulin E (IgE), an antibody isotype involved in the allergy disorder and parasites immunity. FcεRI is a tetra ...

- Tetramer: FCER1A / FCER1B / two FCER1G ::* FcεRII (CD23) :* Secreted Fc receptors ::* Polymeric immunoglobulin receptor (poly-Ig) :* Fc receptor-like molecules

Cytokine receptors

Cytokine receptor Cytokine receptors are receptors that bind to cytokines. In recent years, the cytokine receptors have come to demand the attention of more investigators than cytokines themselves, partly because of their remarkable characteristics, and partly be ...

Type I cytokine receptor Type I cytokine receptors are transmembrane receptors expressed on the surface of cells that recognize and respond to cytokines with four α-helical strands. These receptors are also known under the name ''hemopoietin receptors'', and share a c ...

s ( Hemopoietin receptors) - Share extracellular WSXWS motif, Grouped by common receptor subunits ::*

Common gamma chain The common gamma chain (γc) (or CD132), also known as interleukin-2 receptor subunit gamma or IL-2RG, is a cytokine receptor sub-unit that is common to the receptor complexes for at least six different interleukin receptors: IL-2, IL-4, IL-7 ...

(γ-chain, CD132) :::* IL2R - Heterotrimer:

IL2RA Interleukin-2 receptor alpha chain (also called CD25) is the human protein encoded by the ''IL2RA'' gene. The interleukin 2 (IL2) receptor alpha (IL2RA) and beta (IL2RB) chains, together with the common gamma chain (IL2RG), constitute the high-af ...

(CD25) /

IL2RB Interleukin-2 receptor subunit beta is a protein that in humans is encoded by the ''IL2RB'' gene. Also known as CD122; IL15RB; P70-75. Function The interleukin 2 receptor, which is involved in T cell-mediated immune responses, is present in 3 ...

(CD122) / γ_c :::* IL4R / IL13R - Heterodimer: IL4RA / ( IL13RA1/

IL13RA2 Interleukin-13 receptor subunit alpha-2 (IL-13Rα2), also known as CD213A2 (cluster of differentiation 213A2), is a membrane bound protein that in humans is encoded by the ''IL13RA2'' gene In biology, the word gene (from , ; "... Wilhelm Jo ...

) :::* IL7R - Heterodimer: IL7RA (CD127) / γ-chain :::* IL9R - Heterodimer: IL9R / γ-chain :::* IL15R - Heterotrimer: IL15RA /

/ γ-chain :::* IL21R - Heterodimer: IL21R / γ-chain ::* Common beta chain (β-chain, CD131) :::* IL3R - Heterodimer:

IL3RA Interleukin 3 receptor, alpha (low affinity) (IL3RA), also known as CD123 (Cluster of Differentiation 123), is a human gene. Function The protein encoded by this gene is an interleukin 3 specific subunit of a heterodimeric cytokine receptor. T ...

/ β-chain :::* IL5R - Heterodimer: IL5RA / β-chain :::* GM-CSFR (CD116) - Heterdimer: GM-CSFRA / β-chain ::* Common gp130 subunit (gp130, CD130) :::* IL6R - Heterodimer: IL6RA / gp130 :::* IL11R - Heterodimer: IL11RA / gp130 :::* IL27R - Heterodimer: IL27RA / gp130 :::* OSMR - Heterodimer: OSMR / gp130 :::* LIFR (CD118) - Heterodimer: LIFR / gp130 ::* IL12 receptor beta 1 subunit (IL12RB1) :::* IL12R - Heterodimer: IL12RB1 / IL12RB2 :::* IL23R - Heterodimer: IL23RA / IL12RB1 ::* Others :::* EPOR (Erythropoietin receptor) - Homodimer :::* G-CSFR (CD114) - Homodimer upon ligand binding :::* MPL (CD110, Thrombopoietin receptor) - Homodimer upon ligand binding :::* GHR (Growth hormone receptor) - Homodimer upon ligand binding :::* PRLR (Prolactin receptor) :* Type II cytokine receptor - Lack WSXWS motif ::* Interferon receptors :::* Interferon-α/β receptor (IFNAR) - Heterodimer:

IFNAR1 Interferon-alpha/beta receptor alpha chain is a protein that in humans is encoded by the ''IFNAR1'' gene. Function The protein encoded by this gene is a type I membrane protein that forms one of the two chains of a receptor for type I interfer ...

IFNAR2 Interferon-alpha/beta receptor beta chain is a protein that in humans is encoded by the ''IFNAR2'' gene. Function The protein encoded by this gene is a type I membrane protein that forms one of the two chains of a receptor for interferons al ...

:::* Interferon-γ receptor (IFNGR) - Heterodimer:

IFNGR1 Interferon gamma receptor 1 (IFNGR1) also known as CD119 (Cluster of Differentiation 119), is a protein that in humans is encoded by the ''IFNGR1'' gene. Function The gene ''IFNGR1'' encodes IFN-γR1, which is the ligand-binding chain (alpha) o ...

/ IFNGR2 ::* Interleukin receptors :::* IL10R - Heterodimer: IL10RA / IL10RB :::* IL20R - Heterodimer: IL20RA / IL20RB :::* IL22R - Heterodimer: IL22RA1 / IL10RB :::* IL28R - Heterodimer: IL28RA / IL10RB :*

Immunoglobulin superfamily The immunoglobulin superfamily (IgSF) is a large protein superfamily of cell surface and soluble proteins that are involved in the recognition, binding, or adhesion processes of cells. Molecules are categorized as members of this superfamily ...

(Some members) ::* CSF1 ::*

CD117 Proto-oncogene c-KIT is the gene encoding the receptor tyrosine kinase protein known as tyrosine-protein kinase KIT, CD117 (cluster of differentiation 117) or mast/stem cell growth factor receptor (SCFR). Multiple transcript variants encoding diff ...

(c-KIT) ::* IL1 receptor family ( IL1R) :::* IL1R type 1 (CD121a) :::* IL1R type 2 (CD121b) :::* IL1R accessory protein (IL1RAP) :::*

IL1RL1 Interleukin 1 receptor-like 1, also known as IL1RL1 and ST2, is a protein that in humans is encoded by the ''IL1RL1'' gene. Function IL1RL1 is a member of the Toll-like receptor superfamily based on the function of its intracellular TIR domain ...

(IL33R, ST2) ::* IL18R - Heterodimer: IL18R1 / IL18RAP :* IL17 family ::*

IL17RA Interleukin 17 receptor A, also known as IL17RA and CDw217 (cluster of differentiation w217), is a human gene. Interleukin 17A (IL17A)is a proinflammatory cytokine secreted by activated T-lymphocytes. It is a potent inducer of the maturation of CD ...

::*

IL17RB Interleukin-17 receptor B is a protein that in humans is encoded by the ''IL17RB'' gene. The protein encoded by this gene is a cytokine receptor. This receptor specifically binds to IL17B and IL17E (IL25), but does not bind to IL17(A) or IL17C ...

::*

IL17RC Interleukin-17 receptor C is a protein that in humans is encoded by the ''IL17RC'' gene In biology, the word gene (from , ; "...Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' o ...

::*

IL17RD Interleukin 17 receptor D is a protein that in humans is encoded by the IL17RD gene. Function This gene encodes a membrane protein belonging to the interleukin-17 receptor (IL-17R) protein family. The encoded protein is a component of the int ...

::* IL17RE :* Tumor necrosis factor (TNF) receptor family - Trimeric cytokine receptors :::*

TNFRSF1A Tumor necrosis factor receptor 1 (TNFR1), also known as tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) and CD120a, is a ubiquitous membrane receptor that binds tumor necrosis factor-alpha (TNFα). Function The protein encoded b ...

(CD120a) :::* TNFRSF1B (CD120b) :::* TNFRSF3 (Lymphotoxin βR) :::* TNFRSF4 (CD134, OX40) :::* TNFRSF5 (CD40) :::*

TNFRSF6 The Fas receptor, also known as Fas, FasR, apoptosis antigen 1 (APO-1 or APT), cluster of differentiation 95 (CD95) or tumor necrosis factor receptor superfamily member 6 (TNFRSF6), is a protein that in humans is encoded by the ''FAS'' gene. Fas ...

(FAS) :::* TNFRSF6B :::* TNFRSF7 (CD27) :::* TNFRSF8 (CD30) :::* TNFRSF9 (CD137) :::* TNFRSF10A (CD261) :::*

TNFRSF10B Death receptor 5 (DR5), also known as TRAIL receptor 2 (TRAILR2) and tumor necrosis factor receptor superfamily member 10B (TNFRSF10B), is a cell surface receptor of the TNF-receptor superfamily that binds TRAIL and mediates apoptosis. Function ...

(CD262) :::* TNFRSF10C (CD263) :::* TNFRSF10D (CD264) :::* TNFRSF11A (CD265, RANK) :::* TNFRSF11B (Osteoprotegerin) :::* TNFRSF12A (CD266) :::* TNFRSF13B (CD267) :::* TNFRSF13C :::*

TNFRSF14 Herpesvirus entry mediator (HVEM), also known as tumor necrosis factor receptor superfamily member 14 (TNFRSF14), is a human cell surface receptor of the TNF-receptor superfamily. Nomenclature This protein was originally known as herpesvirus entr ...

(CD268) :::* TNFRSF16 (LNGRF) :::* TNFRSF17 (CD269) :::* TNFRSF18 :::*

TNFRSF19 Tumor necrosis factor receptor superfamily, member 19, also known as TNFRSF19 and TROY is a human gene. The protein encoded by this gene is a member of the TNF-receptor superfamily. This receptor is highly expressed during embryonic development. I ...

:::* TNFRSF21 :::*

TNFRSF25 Death receptor 3 (DR3), also known as tumor necrosis factor receptor superfamily member 25 (TNFRSF25), is a cell surface receptor of the tumor necrosis factor receptor superfamily which mediates apoptotic signalling and differentiation. Its only ...

:::* TNFRSF27 :*

Chemokine receptors Chemokine receptors are cytokine receptors found on the surface of certain cells that interact with a type of cytokine called a chemokine. There have been 20 distinct chemokine receptors discovered in humans. Each has a rhodopsin-like 7-trans ...

- 7-transmembrane

G protein-coupled receptors G protein-coupled receptors (GPCRs), also known as seven-(pass)-transmembrane domain receptors, 7TM receptors, heptahelical receptors, serpentine receptors, and G protein-linked receptors (GPLR), form a large group of evolutionarily-related p ...

::*

CC chemokine receptors CC chemokine receptors (or beta chemokine receptors) are integral membrane proteins that specifically bind and respond to cytokines of the CC chemokine family. They represent one subfamily of chemokine receptors, a large family ...

(CCRs) :::*

CCR1 C-C chemokine receptor type 1 is a protein that in humans is encoded by the ''CCR1'' gene. CCR1 has also recently been designated CD191 (cluster of differentiation 191). Function This gene encodes a member of the beta chemokine receptor fami ...

:::*

CCR2 C-C chemokine receptor type 2 (CCR2 or CD192 ( cluster of differentiation 192) is a protein that in humans is encoded by the ''CCR2'' gene. CCR2 is a CC chemokine receptor. Gene This CCR2 gene is located in the chemokine receptor gene clust ...

:::* CCR3 :::*

CCR4 C-C chemokine receptor type 4 is a protein that in humans is encoded by the ''CCR4'' gene. CCR4 has also recently been designated CD194 (cluster of differentiation 194). The protein encoded by this gene belongs to the G protein-coupled receptor f ...

:::*

CCR5 C-C chemokine receptor type 5, also known as CCR5 or CD195, is a protein on the surface of white blood cells that is involved in the immune system as it acts as a receptor for chemokines. In humans, the ''CCR5'' gene that encodes the CCR5 p ...

:::* CCR6 :::* CCR7 :::*

CCR8 Chemokine (C-C motif) receptor 8, also known as CCR8, is a protein which in humans is encoded by the ''CCR8'' gene. CCR8 has also recently been designated CDw198 (cluster of differentiation w198). Function This gene encodes a member of the bet ...

:::* CCR9 :::*

CCR10 C-C chemokine receptor type 10 is a protein that in humans is encoded by the ''CCR10'' gene. Function Chemokines are a group of small (approximately 8 to 14 kD), mostly basic, structurally related molecules that regulate cell trafficking of va ...

::*

CXC chemokine receptors CXC chemokine receptors are integral membrane proteins that specifically bind and respond to cytokines of the CXC chemokine family. They represent one subfamily of chemokine receptors, a large family of G protein-linked receptors that are ...

(CXCRs) :::* CXCR1 :::* CXCR2 :::*

CXCR3 Chemokine receptor CXCR3 is a Gαi protein-coupled receptor in the CXC chemokine receptor family. Other names for CXCR3 are G protein-coupled receptor 9 (GPR9) and CD183. There are three isoforms of CXCR3 in humans: CXCR3-A, CXCR3-B and chemokin ...

:::*

CXCR4 C-X-C chemokine receptor type 4 (CXCR-4) also known as fusin or CD184 (cluster of differentiation 184) is a protein that in humans is encoded by the ''CXCR4'' gene. The protein is a CXC chemokine receptor. Function CXCR-4 is an alpha-chemokin ...

:::* CXCR5 :::*

CXCR6 C-X-C chemokine receptor type 6 is a protein that in humans is encoded by the ''CXCR6'' gene. CXCR6 has also recently been designated CD186 (cluster of differentiation The cluster of differentiation (also known as cluster of designation or classi ...

:::* CXCR7 ::* C chemokine receptors (XCRs) :::* XCR1 ::* CX₃C chemokine receptors (CX₃CRs) :::* CX₃CR1 (Fractalkine receptor) :*

TGF beta receptors Transforming growth factor beta (TGFβ) receptors are single pass serine/threonine kinase receptors that belong to TGFβ receptor family. They exist in several different isoforms that can be homo- or heterodimeric. (free full text) The numbe ...

- Single transmembrane pass serine/threonine kinase receptors ::* TGFBR1 ::* TGFBR2 ::* TGFBR3

Natural killer cell receptors

Natural killer cell receptors Natural killer cells, also known as NK cells or large granular lymphocytes (LGL), are a type of cytotoxic lymphocyte critical to the innate immune system that belong to the rapidly expanding family of known innate lymphoid cells (ILC) and represen ...

:* Killer activation receptors (KARs) ::* Natural cytotoxicity receptors (NCRs) * NCR1 * NCR2 * NCR3 ::* Natural killer group 2 receptors (NKG2s) * NKG2A * NKG2B * NKG2C *

NKG2D NKG2D is an activating receptor (transmembrane protein) belonging to the NKG2 family of C-type lectin-like receptors. NKG2D is encoded by ''KLRK1'' (killer cell lectin like receptor K1) gene which is located in the NK-gene complex (NKC) situated ...

* NKG2E * NKG2H ::* Activating KIRs :::* KIR2DS1 :* Killer inhibitory receptors (KIRs) ::* Two domains, long cytoplasmic tail * KIR2DL1 * KIR2DL2 * KIR2DL3 *

KIR2DL4 Killer cell immunoglobulin-like receptor 2DL4 is a protein that in humans is encoded by the ''KIR2DL4'' gene. Function Killer cell immunoglobulin-like receptors (KIRs) are transmembrane glycoproteins expressed by natural killer cells and sub ...

* KIR2DL5A * KIR2DL5B ::* Two domains, short cytoplasmic tail * KIR2DS1 * KIR2DS2 * KIR2DS3 * KIR2DS4 * KIR2DS5 ::* Three domains, long cytoplasmic tail * KIR3DL1 * KIR3DL2 * KIR3DL3 ::* Three domains, short cytoplasmic tail :::* KIR3DS1

Others

Leukocyte immunoglobulin-like receptor The leukocyte immunoglobulin-like receptors (LILR) are a family of receptors possessing extracellular immunoglobulin domains. They are also known as CD85, ILTs and LIR, and can exert immunomodulatory effects on a wide range of immune cells.Damia ...

s (LILRs) ::* LILR subfamily A * LILRA1 * LILRA2 * LILRA3 * LILRA4 * LILRA5 * LILRA6 ::* LILR subfamily B *

LILRB1 Leukocyte immunoglobulin-like receptor subfamily B member 1 is a protein that in humans is encoded by the ''LILRB1'' gene. Function This gene is a member of the leukocyte immunoglobulin-like receptor (LIR) family, which is found in a gene clu ...

LILRB2 Leukocyte immunoglobulin-like receptor subfamily B member 2 is a protein that in humans is encoded by the ''LILRB2'' gene. This gene is a member of the leukocyte immunoglobulin-like receptor (LIR) family, which is found in a gene cluster at chr ...

* LILRB3 * LILRB4 * LILRB5 :*

Eicosanoid receptor Most of the eicosanoid receptors are integral membrane protein G protein-coupled receptors (GPCRs) that bind and respond to eicosanoid signaling molecules. Eicosanoids are rapidly metabolized to inactive products and therefore are short-lived. A ...

Antibodies

Antibodies *

Immunoglobulin A Immunoglobulin A (Ig A, also referred to as sIgA in its secretory form) is an antibody that plays a role in the immune function of mucous membranes. The amount of IgA produced in association with mucosal membranes is greater than all other typ ...

(IgA) ** IgA1 ** IgA2 *

Immunoglobulin D Immunoglobulin D (IgD) is an antibody isotype that makes up about 1% of proteins in the plasma membranes of immature B-lymphocytes where it is usually co-expressed with another cell surface antibody called IgM. IgD is also produced in a secreted ...

(IgD) *

Immunoglobulin E Immunoglobulin E (IgE) is a type of antibody (or immunoglobulin (Ig) " isotype") that has been found only in mammals. IgE is synthesised by plasma cells. Monomers of IgE consist of two heavy chains (ε chain) and two light chains, with the � ...

(IgE) * Immunoglobulin G (IgG) ** IgG1 ** IgG2 ** IgG3 **

IgG4 Immunoglobulin G (Ig G) is a Antibody#Classes, type of antibody. Representing approximately 75% of blood plasma, serum immunoglobulins, antibodies in humans, IgG is the most common type of antibody found in Circulatory system, blood circulation. I ...

* Immunoglobulin M (IgM)

Cytokines

Cytokine Cytokines are a broad and loose category of small proteins (~5–25 kDa) important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrin ...

Chemokine Chemokines (), or chemotactic cytokines, are a family of small cytokines or signaling proteins secreted by cells that induce directional movement of leukocytes, as well as other cell types, including endothelial and epithelial cells. In additio ...

s : :* CC chemokines ::*

CCL1 Chemokine (C-C motif) ligand 1 (CCL1) is also known as small inducible cytokine A1 and I-309 in humans. CCL1 is a small glycoprotein that belongs to the CC chemokine family. Genomics CCL1 is encoded by CCL1 gene which is one of the several chem ...

::*

CCL2 ''For the ICAO airport code see Candle Lake Airpark, for the diradical compound see Dichlorocarbene.'' The chemokine (C-C motif) ligand 2 (CCL2) is also referred to as monocyte chemoattractant protein 1 (MCP1) and small inducible cytokine A2. C ...

::*

CCL3 Chemokine (C-C motif) ligand 3 (CCL3) also known as macrophage inflammatory protein 1-alpha (MIP-1-alpha) is a protein that in humans is encoded by the ''CCL3'' gene. Function CCL3 is a cytokine belonging to the CC chemokine family that is i ...

::*

CCL4 Chemokine (C-C motif) ligands 4 (also CCL4) previously known as macrophage inflammatory protein (MIP-1β), is a protein which in humans is encoded by the ''CCL4'' gene. ''CCL4'' belongs to a cluster of genes located on 17q11-q21 of the chromosom ...

::*

CCL5 Chemokine (C-C motif) ligand 5 (also CCL5) is a protein which in humans is encoded by the ''CCL5'' gene. The gene has been discovered in 1990 by ''in situ'' hybridisation and it is localised on 17q11.2-q12 chromosome. It is also known as RANTE ...

::* CCL6 ::*

CCL7 Chemokine (C-C motif) ligand 7 (CCL7) is a small cytokine that was previously called monocyte-chemotactic protein 3 (MCP3). CCL7 is a small protein that belongs to the CC chemokine family and is most closely related to CCL2 (previously called MC ...

::*

CCL8 Chemokine (C-C motif) ligand 8 (CCL8), also known as monocyte chemoattractant protein 2 (MCP2), is a protein that in humans is encoded by the ''CCL8'' gene. CCL8 is a small cytokine belonging to the CC chemokine family. The CCL8 protein is produ ...

::* CCL9/CCL10 ::*

CCL11 C-C motif chemokine 11 also known as eosinophil chemotactic protein and eotaxin-1 is a protein that in humans is encoded by the CCL11 gene. This gene is encoded on three exons and is located on chromosome 17. Function CCL11 is a small cytokine ...

::* CCL12 ::*

CCL13 Chemokine (C-C motif) ligand 13 (CCL13) is a small cytokine belonging to the CC chemokine family. Its gene is located on human chromosome 17 within a large cluster of other CC chemokines. CCL13 induces chemotaxis in monocytes, eosinophils, T ly ...

::* CCL14 ::*

CCL15 Chemokine (C-C motif) ligand 15 (CCL15) is a small cytokine belonging to the CC chemokine family that is also known as leukotactin-1, MIP5 and HCC-2. CCL15 is expressed in liver, small intestine, colon, and in certain leukocytes and macrophages ...

::* CCL16 ::*

CCL17 CCL17 is a powerful chemokine produced in the thymus and by antigen-presenting cells like dendritic cells, macrophages, and monocytes. CCL17 plays a complex role in cancer. It attracts T-regulatory cells allowing for some cancers to evade an imm ...

::*

CCL18 Chemokine (C-C motif) ligand 18 (CCL18) is a small cytokine belonging to the CC chemokine family. The functions of CCL18 have been well studied in laboratory settings, however the physiological effects of the molecule in living organisms have ...

::* CCL19 ::* CCL20 ::*

CCL21 Chemokine (C-C motif) ligand 21 (CCL21) is a small cytokine belonging to the CC chemokine family. This chemokine is also known as 6Ckine (because it has six conserved cysteine residues instead of the four cysteines typical to chemokines), exodus- ...

::*

CCL22 C-C motif chemokine 22 is a protein that in humans is encoded by the ''CCL22'' gene. The protein encoded by this gene is secreted by dendritic cells and macrophages, and elicits its effects on its target cells by interacting with cell surface che ...

::*

CCL23 Chemokine (C-C motif) ligand 23 (CCL23) is a small cytokine belonging to the CC chemokine family that is also known as Macrophage inflammatory protein 3 (MIP-3) and Myeloid progenitor inhibitory factor 1 (MPIF-1). CCL23 is predominantly expresse ...

::* CCL24 ::* CCL25 ::*

CCL26 Chemokine (C-C motif) ligand 26 (CCL26) is a small cytokine belonging to the CC chemokine family that is also called Eotaxin-3, Macrophage inflammatory protein 4-alpha (MIP-4-alpha), Thymic stroma chemokine-1 (TSC-1), and IMAC. It is expressed by ...

::*

CCL27 C-C motif chemokine ligand 27 is a protein that in humans is encoded by the CCL27 gene. Function This gene is one of several CC cytokine genes clustered on the p-arm of chromosome 9. Cytokines are a family of secreted proteins involved in ...

::*

CCL28 Chemokine (C-C motif) ligand 28 (CCL28), also known as mucosae-associated epithelial chemokine (MEC), CCK1 and SCYA28, is a chemokine. CCL28 regulates the chemotaxis of cells that express the chemokine receptors CCR3 and CCR10. CCL28 is express ...

:* CXC chemokines ::* CXCL1 ::* CXCL2 ::*

CXCL3 Chemokine (C-X-C motif) ligand 3 (CXCL3) is a small cytokine belonging to the CXC chemokine family that is also known as ''GRO3 oncogene'' (GRO3), ''GRO protein gamma'' (GROg) and ''macrophage inflammatory protein-2-beta'' (MIP2b). CXCL3 controls ...

::*

CXCL4 Platelet factor 4 (PF4) is a small cytokine belonging to the CXC chemokine family that is also known as chemokine (C-X-C motif) ligand 4 (CXCL4) . This chemokine is released from alpha-granules of activated platelets during platelet aggregation ...

::* CXCL5 ::* CXCL6 ::* CXCL7 ::*

CXCL8 Interleukin 8 (IL-8 or chemokine (C-X-C motif) ligand 8, CXCL8) is a chemokine produced by macrophages and other cell types such as epithelial cells, airway smooth muscle cells and endothelial cells. Endothelial cells store IL-8 in their storage ...

::* CXCL9 ::*

CXCL10 C-X-C motif chemokine ligand 10 (CXCL10) also known as Interferon gamma-induced protein 10 (IP-10) or small-inducible cytokine B10 is an 8.7 kDa protein that in humans is encoded by the ''CXCL10'' gene. C-X-C motif chemokine 10 is a small cytokin ...

::*

CXCL11 C-X-C motif chemokine 11 (CXCL11) is a protein that in humans is encoded by the ''CXCL11'' gene. C-X-C motif chemokine 11 is a small cytokine belonging to the CXC chemokine family that is also called ''Interferon-inducible T-cell alpha chemoattra ...

::* CXCL12 ::*

CXCL13 Chemokine (C-X-C motif) ligand 13 (CXCL13), also known as B lymphocyte chemoattractant (BLC) or B cell-attracting chemokine 1 (BCA-1), is a protein ligand that in humans is encoded by the ''CXCL13'' gene. Function CXCL13 is a small chemokine ...

::* CXCL14 ::* CXCL15 ::* CXCL16 ::* CXCL17 :* C chemokines ::* XCL1 ::* XCL2 :* CX₃C chemokines ::* CX₃CL1 (Fractalkine, Neurotactin) *

Interferons Interferons (IFNs, ) are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten the ...

Interferon type I The type-I interferons (IFN) are cytokines which play essential roles in inflammation, immunoregulation, tumor cells recognition, and T-cell responses. In the human genome, a cluster of thirteen functional IFN genes is located at the 9p21.3 cyt ...

***

IFN-α The type-I interferons (IFN) are cytokines which play essential roles in inflammation, immunoregulation, tumor cells recognition, and T-cell responses. In the human genome, a cluster of thirteen functional IFN genes is located at the 9p21.3 cyt ...

***

IFN-β The type-I interferons (IFN) are cytokines which play essential roles in inflammation, immunoregulation, tumor cells recognition, and T-cell responses. In the human genome, a cluster of thirteen functional IFN genes is located at the 9p21.3 cyt ...

*** IFN-ω **

Interferon type II Interferons (IFNs, ) are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten the ...

***

IFN-γ Interferon gamma (IFN-γ) is a dimerized soluble cytokine that is the only member of the type II class of interferons. The existence of this interferon, which early in its history was known as immune interferon, was described by E. F. Wheelock ...

Interleukins Interleukins (ILs) are a group of cytokines (secreted proteins and signal molecules) that are expressed and secreted by white blood cells (leukocytes) as well as some other body cells. The human genome encodes more than 50 interleukins and related ...

IL1A Interleukin-1 alpha (IL-1 alpha) also known as hematopoietin 1 is a cytokine of the interleukin 1 family that in humans is encoded by the ''IL1A'' gene. In general, Interleukin 1 is responsible for the production of inflammation, as well as the ...

IL1B Interleukin-1 beta (IL-1β) also known as leukocytic pyrogen, leukocytic endogenous mediator, mononuclear cell factor, lymphocyte activating factor and other names, is a cytokine protein that in humans is encoded by the ''IL1B'' gene."Catabolin" ...

:* IL1RA :* IL2 :* IL3 :* IL4 :* IL5 :* IL6 :* IL7 :* IL8 :* IL9 :* IL10 :* IL11 :* IL12 :* IL13 :* IL14 :* IL15 :* IL16 :*

IL17A Interleukin-17A is a protein that in humans is encoded by the ''IL17A'' gene. In rodents, IL-17A used to be referred to as CTLA8, after the similarity with a viral gene (). Function The protein encoded by this gene is a proinflammatory cytokin ...

IL17F Interleukin 17F (IL-17F) is signaling protein that is in human is encoded by the ''IL17F'' gene and is considered a pro-inflammatory cytokine. This protein belongs to the interleukin 17 family and is mainly produced by the T helper 17 cells afte ...

:* IL18 :* IL19 :* IL20 :* IL21 :* IL22 :* IL23 :* IL24 :* IL25 :* IL26 :* IL27 :* IL28A :* IL28B :* IL29 :* IL30 :* IL31 :* IL32 :* IL33 :* IL34 :* IL35 :* IL36A :* IL36B :* IL36G :* IL36RA :* IL37 :* TSLP :* Leukemia inhibitory factor, LIF (Leukemia inhibitory factor) :* Oncostatin M, OSM (Oncostatin M) * Tumor necrosis factors :* TNFA :* TNFB (Lymphotoxin-α) :* Lymphotoxin beta, TNFC (Lymphotoxin-β) :* TNFSF4 (OX40L) :* TNFSF5 (CD40L) :* TNFSF6 (FasL) :* TNFSF7 (CD70, CD27L) :* TNFSF8 (CD153, CD30L) :* TNFSF9 (4-1BBL) :* TNFSF10 (TRAIL) :* TNFSF11 (RANK-L, OPG-L) :* TNFSF12 (TWEAK) :* TNFSF13 (APRIL, CD256) :* TNFSF13B (BAFF, CD257) :* TNFSF14 (LIGHT, CD258) :* TNFSF15 (VEGI) :* TNFSF18 :* EDA (gene), EDA * Colony stimulating factors :* CSF1 (M-CSF) :* CSF2 (GM-CSF) :* CSF3 (G-CSF)

MHCs

Major histocompatibility complex * MHC class I * HLA-A * HLA-B * HLA-C * HLA-E * HLA-F * HLA-G *MHC class II * HLA-DM ** HLA-DMA, α ** HLA-DMB, β * HLA-DO ** HLA-DOA, α ** HLA-DOB, β * HLA-DP ** HLA-DPA1, α1 ** HLA-DPB1, β1 * HLA-DQ ** HLA-DQA1, α1 ** HLA-DQA2, α2 ** HLA-DQB1, β1 ** HLA-DQB2, β2 ** HLA-DQB3, β3 * HLA-DR ** HLA-DRA, α ** HLA-DRB1, β1 ** HLA-DRB3 (gene), β3 ** HLA-DRB4, β4 ** HLA-DRB5, β5

Complement proteins

* Early stage (divided by pathway) :*

::* C1Q complex - Complement component 1R, C1R / Complement component 1S, C1S ::* Complement component 4, C4 - C4a ::* Complement component 2, C2 :*

::* MASP1 (protein), MASP1 / MASP2 (protein), MASP2 ::*

:* Alternative complement pathway ::* Complement factor B, Factor B ::* Factor D ::* Factor P (Properdin) * Middle stage :* Complement component 3, C3 - C3a (complement), C3a / C3b / iC3b :* Complement component 5, C5 - Complement component 5a, C5a :* C3-convertase :* C5-convertase * Late stage :* Membrane attack complex (MAC) ::* Complement component 6, C6 ::* Complement component 7, C7 ::* C8 complex, C8 ::* Complement component 9, C9 * Complement pathway inhibitors :* C1-inhibitor - Classical, Lectin, Alternate :* Decay-accelerating factor (CD59) - Classical, Lectin, Alternate :* Complement factor I, Factor I - Classical, Lectin, Alternate :* C4BP - Classical, Lectin :* Factor H - Alternate

Antimicrobial peptides

Transcription factors

* NF-κB * AP-1 transcription factor, AP-1 * Interferon regulatory factors (IRF) * NFAT * T-bet - T_H1 differentiation * GATA3 - T_H2 differentiation * RORγT - T_H17 differentiation * BCL6 - T_FH differentiation * FoxP3 - T_reg differentiation

Signaling pathways

* JAK-STAT signaling pathway * TGF beta signaling pathway * TLR signalling pathway

Cell adhesion molecules (CAMs)

Cell adhesion molecules * Integrins - Obligate heterodimers of one alpha and one beta subunits :* Alpha subunits :* Beta subunits :* Dimers ::* Cytoadhesin receptor :::* Integrin alpha6beta4 :::* Glycoprotein IIb/IIIa - Heterodimer: ITGA2B / ITGB3 ::* Fibrinogen receptor :::* Macrophage-1 antigen (CR3) - Heterodimer:

/ CD18 ::* Fibronectin receptor: :::* Integrin alpha2beta1 :::* Integrin alpha4beta1 :::* Integrin alpha5beta1 ::* Leukocyte-adhesion receptor: :::* LFA-1 - Heterodimer: CD11a / CD18 :::* Macrophage-1 antigen (CR3) - Heterodimer:

/ CD18 :::* Integrin alphaXbeta2 (CR4) - Heterodimer:

/ CD18 ::* Very late antigen receptor: :::* Integrin alpha1beta1 :::* Integrin alpha2beta1 :::* Integrin alpha3beta1 :::* VLA-4 - Heterodimer: CD49d / CD29 :::* Alpha-5 beta-1 :::* Integrin alpha6beta1 ::* Vitronectin receptor: :::* Alpha-v beta-3 :::* Alpha-v beta-5 * Immunoglobulin superfamily CAMs ::* SynCAMs - Synaptic cell adhesion molecules ::* NCAMs - Neural cell adhesion molecules ::* Intercellular adhesion molecules (ICAMs) ::* VCAM-1 (CD106) ::* PECAM-1 (CD31) ::* L1 family ::* SIGLEC family - Sialic acid binding lectins ::* CTX family ::* Nectins ::* CD2 family :::* CD2 :::* CD58 :::* Signaling lymphocytic activation molecules (SLAMs) * Cadherins * Selectins :* E-selectin :* L-selectin :* P-selectin * Others :* Lymphocyte homing receptors ::* CD34 ::* GLYCAM-1 ::* Addressin (MAdCAM-1) :* CD44 :* Carcinoembryonic antigens :* CD24 :* CD44 :* CD146 :* CD164

Others

* CD69 * Sphingosine-1-phosphate receptors * Co-stimulatory molecules :* CD80 - Expressed by APCs :* CD86 - Expressed by APCs :* CD28 family receptors ::* CD28 - Expressed by T Cells ::* CD278 (ICOS) - Homodimer, expressed by T Cells ::* CTLA-4 (CD152) ::* PD-1 (CD279)

Immune system disorders

Immune disorder

Hypersensitivity and Allergy

:* Type 1 hypersensitivity / Allergy / Atopy ::* Foreign (

) :::* Atopic eczema :::* Allergic urticaria :::* Allergic rhinitis (Hay fever) :::* Allergic asthma :::* Anaphylaxis :::* Food allergy ::::* Milk allergy ::::* Egg allergy ::::* Peanut allergy ::::* Tree nut allergy ::::* Seafood allergy ::::* Soy allergy ::::* Wheat allergy ::::* Garlic allergy :::* Penicillin allergy :* Type 2 hypersensitivity / Antibody-dependent cell-mediated cytotoxicity (ADCC) ::* Foreign :::* Pernicious anemia :::* Hemolytic disease of the newborn ::* Autoimmune :::* Cytotoxicity, Cytotoxic ::::* Autoimmune hemolytic anemia ::::* Idiopathic thrombocytopenic purpura ::::* Bullous pemphigoid ::::* Pemphigus vulgaris ::::* Rheumatic fever ::::* Goodpasture's syndrome :::* Hypersensitivity#Type V, Type 5 / Receptor mediated ::::* Graves' disease ::::* Myasthenia gravis :* Type 3 hypersensitivity / Immune complex ::* Foreign :::* Henoch–Schönlein purpura :::* Hypersensitivity vasculitis :::* Reactive arthritis :::* Farmer's lung :::* Post-streptococcal glomerulonephritis :::* Serum sickness :::* Arthus reaction ::* Autoimmune :::* Systemic lupus erythematosus :::* Subacute bacterial endocarditis :::* Rheumatoid arthritis :* Type 4 hypersensitivity (Delayed-Type Hypersensitivity) ::* Foreign :::* Allergic contact dermatitis :::* Mantoux test ::* Autoimmune :::* Diabetes mellitus type 1 :::* Hashimoto's thyroiditis :::* Guillain–Barré syndrome :::* Multiple sclerosis :::* Coeliac disease :::* Giant-cell arteritis ::* GVHD (Graft-versus-host disease) :::* Transfusion-associated graft versus host disease :* Unknown/Multiple types ::* Foreign :::* Hypersensitivity pneumonitis :::* Allergic bronchopulmonary aspergillosis :::* Transplant rejection :::* Latex allergy (I+IV) ::* Autoimmune :::* Sjögren's syndrome :::* Autoimmune hepatitis :::* Autoimmune polyendocrine syndrome (APS1 / APS2) :::* Autoimmune adrenalitis :::* Systemic autoimmune disease

Immunodeficiency

Immunodeficiency :* Primary immunodeficiency :* Acquired immunodeficiency :* Complement deficiency

Cancers of the immune system

Myeloid diseases

Inflammatory diseases

:* Sepsis :* Inflammatory bowel disease (IBD) :* Cytokine storm

Immunoproliferative immunoglobulin disorders

Lymphatic organ disease

Immunologic techniques and tests

* Flow cytometry * Mass cytometry * Histology * Adoptive cell transfer * Experiments in immunology * Genetically modified mouse * Immunofluorescence * Immunofixation * Immunoadsorption * MHC multimer * Hybridoma technology :* Rabbit hybridoma :* Developmental studies hybridoma bank

Immunology and health

* Prevention (medical), Prevention * Immunostimulants * Immunotherapy :* Activation immunotherapy ::* Cancer immunotherapy ::* Autologous immune enhancement therapy :* Immunosuppression ::* Sublingual immunotherapy ::* Allergen immunotherapy ::* Immunosuppressive drug * Artificial induction of immunity * Immunization :* Active immunotherapy :* Passive immunity ::* Temporarily induced immunity ::* Adoptive immunity * Vaccination :* Vaccine-naive :* Vaccine :* Herd immunity :* Adjuvant * Organ transplantation :* Allotransplant :* Transplant rejection

Immunologists

List of immunologists

Immunology lists

* List of autoimmune diseases * List of immunologists * List of viruses * List of human clusters of differentiation * List of vaccine ingredients * List of allergens * List of cytokines * List of cytokine receptors * List of pattern recognition receptors * List of tissue-resident macrophages * List of branches of immunology * List of acute-phase proteins

References

External links

BMC: Immunology
BioMed Central:Immunology is an open access journal publishing original peer-reviewed research articles. * Nature Reviews Immunology
journal home

Janeway's Immunobiology textbook
Searchable free online version at the National Center for Biotechnology Information
Overview
at Medical College of Georgia
MUGEN NoE
murine models for immunological disease
Transplantation Immunology
Interesting web site made by the faculty of medicine of the University of Geneva dealing with the immunological issues linked with the transplantation of materials genetically different between donor and recipient (hematopoietical stem cells, organs or the transfusion of blood).
Online lectures in immunology
University of South Carolina
BRT-Burleson Research Technologies
Tests the effects of pharmaceuticals in the developmental stage on the immune system. {{Outline footer Outlines of natural sciences, Immunology Immunology, * Immune system, Immunology lists, Outlines of health and fitness, Immunology Wikipedia outlines, Immunology