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Primary Immunodeficiency
Primary immunodeficiencies are disorders in which part of the body's immune system is missing or does not function normally. To be considered a ''primary'' immunodeficiency (PID), the immune deficiency must be inborn, not caused by secondary factors such as other disease, drug treatment, or environmental exposure to toxins. Most primary immunodeficiencies are genetic disorders; the majority are diagnosed in children under the age of one, although milder forms may not be recognized until adulthood. While there are over 430 recognized inborn errors of immunity (IEIs) as of 2019, the vast majority of which are PIDs, most are very rare. About 1 in 500 people in the United States are born with a primary immunodeficiency. Immune deficiencies can result in persistent or recurring infections, auto-inflammatory disorders, tumors, and disorders of various organs. There are currently limited treatments available for these conditions; most are specific to a particular type of PID. Research ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immune System
The immune system is a network of biological systems that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to bacteria, as well as Tumor immunology, cancer cells, Parasitic worm, parasitic worms, and also objects such as wood splinters, distinguishing them from the organism's own healthy biological tissue, tissue. Many species have two major subsystems of the immune system. The innate immune system provides a preconfigured response to broad groups of situations and stimuli. The adaptive immune system provides a tailored response to each stimulus by learning to recognize molecules it has previously encountered. Both use humoral immunity, molecules and cell-mediated immunity, cells to perform their functions. Nearly all organisms have some kind of immune system. Bacteria have a rudimentary immune system in the form of enzymes that protect against bacteriophage, viral infections. Other basic immune mechanisms evolved in ancien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T Cell
T cells (also known as T lymphocytes) are an important part 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 receptor (TCR) on their cell surface receptor, cell surface. T cells are born from hematopoietic stem cells, found in the bone marrow. Developing T cells then migrate to the thymus gland to develop (or mature). T cells derive their name from the thymus. After migration to the thymus, the precursor cells mature into several distinct types of T cells. T cell differentiation also continues after they have left the thymus. Groups of specific, differentiated T cell subtypes have a variety of important functions in controlling and shaping the immune response. One of these functions is immune-mediated cell death, and it is carried out by two major subtypes: Cytotoxic T cell, CD8+ "killer" (cytotoxic) and T helper cell, CD4+ "helper" T cells. (These are named for the presen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitogen
A mitogen is a small bioactive protein or peptide that induces a cell to begin cell division, or enhances the rate of division (mitosis). Mitogenesis is the induction (triggering) of mitosis, typically via a mitogen. The cell cycle Mitogens act primarily by influencing a set of proteins which are involved in the restriction of progression through the cell cycle. The G1 checkpoint is controlled most directly by mitogens: further cell cycle progression does not need mitogens to continue. The point where mitogens are no longer needed to move the cell cycle forward is called the " restriction point" and depends on cyclins to be passed.Bohmer et al. "Cytoskeletal Integrity Is Required throughout the Mitogen Stimulation Phase of the Cell Cycle and Mediates the Anchorage-dependent Expression of Cyclin DI". January 1996, Molecular Biology of the Cell, Vol. 7, pp. 101-111. One of the most important of these is TP53, a gene which produces a family of proteins known as p53. It, combined ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD80
The Cluster of differentiation 80 (also CD80 and B7-1) is a B7, type I membrane protein in the immunoglobulin superfamily, with an extracellular immunoglobulin constant-like domain and a variable-like domain required for receptor binding. It is closely related to CD86, another B7 protein (B7-2), and often works in tandem. Both CD80 and CD86 interact with Co-stimulation, costimulatory receptors CD28, CTLA-4 (CD152) and the p75 neurotrophin receptor. Structure CD80 is a member of the B7 (protein), B7 family, which consists of molecules present at Antigen-presenting cell, APCs and their receptors present on the T cell, T-cells. CD80 is present specifically on Dendritic cell, DC, activated B cell, B-cells, and macrophages, but also T cell, T-cells. CD80 is also a Transmembrane protein, transmembrane glycoprotein and a member of the Immunoglobulin superfamily, Ig superfamily. It is composed of 288 amino acids, and its mass is 33 Dalton (unit), kDa. It consists of two Ig-like extracel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD25
The interleukin-2 receptor alpha chain (also called Tac antigen, P55, and mainly CD25) is a protein involved in the assembly of the high-affinity interleukin-2 receptor, consisting of alpha (''IL2RA''), beta ('' IL2RB'') and the common gamma chain (''IL2RG''). As the name indicates, this receptor interacts with interleukin-2, a pleiotropic cytokine which plays an important role in immune homeostasis. Genetics The human protein interleukin-2 receptor subunit alpha is encoded by a gene called ''IL2RA'' with a length around 51,6 kb. Alternative names for this protein coding gene are ''IL2R'', ''IDDM10'' and ''TCGFR''. Location of ''IL2RA'' in human genome is on the short arm of 10th chromosome (10p15.1). Several frequent point mutations, single nucleotide polymorphism (SNP), have been identified in or in close proximity to ''IL2RA'' gene in the population. These SNPs have been linked mainly to susceptibility to immune dysregulation disorders, with majority found in research on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HLA-DR
HLA-DR is an MHC class II cell surface receptor encoded by the human leukocyte antigen complex on chromosome 6 region 6p21.31. The complex of HLA-DR (Human Leukocyte Antigen – DR isotype) and peptide, generally between 9 and 30 amino acids in length, constitutes a ligand for the T-cell receptor (TCR). HLA (human leukocyte antigens) were originally defined as cell surface antigens that mediate graft-versus-host disease. Identification of these antigens has led to greater success and longevity in organ transplant. Antigens most responsible for graft loss are HLA-DR (first six months), HLA-B (first two years), and HLA-A (long-term survival). Good matching of these antigens between host and donor is most critical for achieving graft survival. HLA-DR is also involved in several autoimmune conditions, disease susceptibility and disease resistance. It is also closely linked to HLA-DQ and this linkage often makes it difficult to resolve the more causative factor in disease. HLA-DR mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD14
CD14 ( cluster of differentiation 14) is a human protein made mostly by macrophages as part of the innate immune system. It helps to detect bacteria in the body by binding lipopolysaccharide (LPS), a pathogen-associated molecular pattern (PAMP). CD14 exists in two forms, one anchored to the membrane by a glycosylphosphatidylinositol (GPI) tail (mCD14), the other a soluble form (sCD14). Soluble CD14 either appears after shedding of mCD14 (48 kDa) or is directly secreted from intracellular vesicles (56 kDa). The x-ray crystal structure of human CD14 reveals a monomeric, bent solenoid structure containing a hydrophobic amino-terminal pocket. CD14 was the first described pattern recognition receptor. Function CD14 acts as a co-receptor (along with the Toll-like receptor TLR 4 and MD-2) for the detection of bacterial lipopolysaccharide (LPS). CD14 can bind LPS only in the presence of lipopolysaccharide-binding protein (LBP). Although LPS is considered its main ligand, CD14 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Killer Cell
Natural killer cells, also known as NK cells, are a type of cytotoxic lymphocyte critical to the innate immune system. They are a kind of large granular lymphocytes (LGL), and belong to the rapidly expanding family of known innate lymphoid cells (ILC) and represent 5–20% of all circulating lymphocytes in humans. The role of NK cells is analogous to that of cytotoxic T cells in the vertebrate adaptive immune response. NK cells provide rapid responses to virus-infected cells, stressed cells, tumor cells, and other intracellular pathogens based on signals from several activating and inhibitory receptors. Most immune cells detect the antigen presented on MHC class I, major histocompatibility complex I (MHC-I) on infected cell surfaces, but NK cells can recognize and kill stressed cells in the absence of antibodies and MHC, allowing for a much faster immune reaction. They were named "natural killers" because of the notion that they do not require activation to kill cells that are m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 binds to iC3b (inactive derivative of C3b), C3dg, or C3d.Frank K, Atkinson JP (2001). "Complement system." In Austen KF, Frank K, Atkinson JP, Cantor H. eds. ''Samter's Immunologic Diseases, 6th ed. Vol. 1,'' p. 281–298, Philadelphia: Lippincott Williams & Wilkins, . B cells express CR2 on their surfaces, allowing the complement system to play a role in B-cell activation and maturation. Interactions Complement receptor 2 interacts with CD19, and, on mature B cells, forms a complex with CD81 (TAPA-1). The CR2-CD19-CD81 complex is often called the B cell co-receptor complex,Abbas AK, Lichtman AH (2003). ''Cellular and Molecular Immunology, 5th ed.'' Philadelphia: Saunders, because CR2 binds to opsonized antigens through attached ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD20
B-lymphocyte antigen CD20 or CD20 is B lymphocyte cell-surface molecule. It is a 33-37 kDa non-glycosylated protein. CD20 is expressed on the surface of B-cells from the pre-B phase, the expression is lost in terminally differentiated plasma cells. CD20 is used as a therapeutical target of B-cell malignancies and autoimmune diseases. Gene In humans CD20 is encoded by the ''MS4A1'' gene localized to 11q12. The gene is 16 kbp long and consists of 8 exons. There are at least 3 mRNA transcripts (resulting from alternative splicing), that are all translated into an identical full-length CD20 protein product. Variants 1 and 2 are poorly translated due to inhibitory upstream open reading frames and stem-loop structures within their 5' untranslated regions. The relative abundance of translation-competent variant 3, as opposed to the poorly translated variants 1 and 2, may be a key determinant of CD20 levels in normal and malignant human B cells and their responses to CD20-d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CD19
B-lymphocyte antigen CD19, also known as CD19 molecule ( Cluster of Differentiation 19), B-Lymphocyte Surface Antigen B4, T-Cell Surface Antigen Leu-12 and CVID3 is a transmembrane protein that in humans is encoded by the gene ''CD19''. In humans, CD19 is expressed in all B lineage cells. Contrary to some early doubts, human plasma cells do express CD19. CD19 plays two major roles in human B cells: on the one hand, it acts as an adaptor protein to recruit cytoplasmic signaling proteins to the membrane; on the other, it works within the CD19/ CD21 complex to decrease the threshold for B cell receptor signaling pathways. Due to its presence on all B cells, it is a biomarker for B lymphocyte development, lymphoma diagnosis and can be utilized as a target for leukemia immunotherapies. Structure In humans, CD19 is encoded by the 7.41 kilobase ''CD19'' gene located on the short arm of chromosome 16. It contains at least fifteen exons, four that encode extracellular domain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
