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Pemphigus
Pemphigus ( or ) is a rare group of blistering autoimmune diseases that affect the skin and mucous membranes. The name is derived from the Greek root ''pemphix'', meaning "blister". In pemphigus, autoantibody, autoantibodies form against desmoglein, which forms the "glue" that attaches adjacent Epidermis (skin), epidermal cells via attachment points called desmosomes. When autoantibodies attack desmogleins, the cells become separated from each other and the epidermis becomes detached, a phenomenon called acantholysis. This causes blisters that slough off and turn into Ulcer (dermatology), sores. In some cases, these blisters can cover a large area of the skin. Originally, the cause of this disease was unknown, and "pemphigus" was used to refer to any blistering disease of the skin and mucosa. In 1964, researchers found that the blood of patients with pemphigus contained antibodies to the layers of skin that separate to form the blisters. In 1971, an article investigating th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pemphigus Vulgaris
Pemphigus vulgaris is a rare chronic blistering skin disease and the most common form of pemphigus. Pemphigus was derived from the Greek word ''pemphix'', meaning blister. It is classified as a type II hypersensitivity reaction in which antibody, antibodies are formed against desmosomes, components of the skin that function to keep certain layers of skin bound to each other. As desmosomes are attacked, the layers of skin separate and the clinical picture resembles a blister. These blisters are due to acantholysis, or breaking apart of intercellular connections through an autoantibody-mediated response. Over time the condition inevitably progresses without treatment: lesions increase in size and distribution throughout the body, behaving physiologically like a severe burn. Before the advent of modern treatments, mortality for the disease was close to 90%. Today, the mortality rate with treatment is in the range of 5% to 15%, after the introduction of corticosteroids as primary tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acantholysis
Acantholysis is the loss of intercellular connections, such as desmosomes, resulting in loss of cohesion between keratinocytes,Kumar, Vinay; Fausto, Nelso; Abbas, Abul (2004) ''Robbins & Cotran Pathologic Basis of Disease'' (7th ed.). Saunders. Page 1230. . seen in diseases such as pemphigus vulgaris, Grover’s disease, and Hailey-Hailey Disease. It is absent in bullous pemphigoid, making it useful for differential diagnosis. This disruption between cells causes intra-epidermal clefts, vesicles and bullae due to cells becoming rounded and no longer attached to one another. Focusing on Pemphigus vulgaris, a blistering auto-immune disease, during acantholysis, circulating autoantibodies cause disruption of cell-cell and cell-matrix adhesion. The antibodies circulate against intercellular adhesion structures and demosomal protein desmoglein (DSG), which causes the disruption. Acantholytic cells also known as Tzanck cells are a distinguishing feature when diagnosing Pemphigus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraneoplastic Pemphigus
Paraneoplastic pemphigus (PNP) is an autoimmune disorder stemming from an underlying tumor. It is hypothesized that antigens associated with the tumor trigger an immune response resulting in blistering of the skin and mucous membranes. While patients with malignant and benign tumors are both at risk, malignancy is associated with high mortality rates (near 90%). Current treatment focuses on general wound healing and administering corticosteroids, which has not demonstrated a high success rate. Recent research developments aim to treat the underlying tumor in order to alleviate the symptoms of PNP. Signs and symptoms While the presence of lesions is the denominator among patients with PNP, the characteristics of the lesions differ. The five clinical presentations of lesions associated with PNP include: * "Pemphigus-like": Flaccid blister (discrete), crusts over the raw exuding skin lesions * "Pemphigoid-like": Tense blister(s) on brick red erythema * "Erythema multiforme-like": Sev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pemphigus Foliaceus
Pemphigus foliaceus is an autoimmune blistering disease of the skin. Pemphigus foliaceus causes a characteristic inflammatory attack at the subcorneal layer of epidermis, which results in skin lesions that are scaly or crusted erosions with an erythematous (red) base.Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). Page 558–562. McGraw-Hill. . Mucosal involvement is absent even with widespread disease. If there is an autoimmune IgG buildup in the epidermis, then nearly all of the antibodies are aimed against desmoglein 1. The effect of the antibodies and the immunological pathway is most likely one of three mechanisms: * Steric hindrance of the desmoglein 1: The antibody caps off the site for intracellular binding to another keratinocyte. * Activation of an endocytic pathway: The antibody activates a pathway which causes an internalization of desmogleïn 1, which in turn causes a loss of adhesion. * Disruption of function: In this case, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmoglein 3
Desmoglein-3 is a protein that in humans is encoded by the ''DSG3'' gene. In the skin epidermis Desmoglein-3 is expressed in the basal lower layers of the epidermis, and dominates in terms of expression on mucosal surfaces compared to Desmoglein-1. Function Desmosomes are cell-cell junctions between epithelial, myocardial, and certain other cell types. Desmoglein 3 is a calcium-binding transmembrane glycoprotein component of desmosomes in vertebrate epithelial cells. Currently, four desmoglein subfamily members have been identified and all are members of the cadherin cell adhesion molecule superfamily. These desmoglein gene family members are located in a cluster on chromosome 18. This protein, along with Desmoglein-1, has been identified as the autoantigen of the autoimmune skin blistering disease pemphigus vulgaris Pemphigus vulgaris is a rare chronic blistering skin disease and the most common form of pemphigus. Pemphigus was derived from the Greek word ''pemphix'', meani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. Production Antibodies are produced by B cells in two ways: (i) randomly, and (ii) in response to a foreign protein or substance within the body. Initially, one B cell produces one specific kind of antibody. In either case, the B cell is allowed to proliferate or is killed off through a process called clonal deletion. Normally, the immune system is able to recognize and ignore the body's own healthy proteins, cells, and tissues, and to not overreact to non-threatening substances in the environment, such as foods. Sometimes, the immune system ceases to recognize one or more of the body's normal constituents as "self", leading to production of pathological autoantibodies. Autoantibodies may also play a nonpathological role; for instance they ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmoglein
The desmogleins are a family of desmosomal cadherins consisting of proteins DSG1, DSG2, DSG3, and DSG4. They play a role in the formation of desmosomes that join cells to one another. Pathology Desmogleins are targeted in the autoimmune disease pemphigus. Desmoglein proteins are a type of cadherin, which is a transmembrane protein that binds with other cadherins to form junctions known as desmosomes between cells. These desmoglein proteins thus hold cells together, but, when the body starts producing Antibody, antibodies against desmoglein, these junctions break down, and this results in subsequent blister or Vesicle (biology and chemistry), vesicle formation.Bolognia JL, Jorizzo JL, Schaffer JV, editors. Dermatology. 3rd ed. Philadelphia: Elsevier Saunders; 2012 References External links * * Cadherins Single-pass transmembrane proteins Protein families {{Membrane-protein-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intraepidermal Neutrophilic IgA Dermatosis
IgA pemphigus is a subtype of pemphigus with two distinct forms: * ''Subcorneal pustular dermatosis'' (also known as Sneddon–Wilkinson disease and pustulosis subcornealis) is skin condition that is a rare, chronic, recurrent, pustular eruption characterized histopathologically by subcorneal pustules that contain abundant neutrophils.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . This is distinct from and not to be confused with subcorneal pustular dermatosis type of IgA pemphigus. Sneddon's syndrome, also known as Ehrmann-Sneddon syndrome, is also a different syndrome. * ''Intraepidermal neutrophilic IgA dermatosis'' is characterized histologically by intraepidermal bullae with neutrophils, some eosinophils, and acantholysis. History Early descriptions were made by Darrell Wilkinson, a British dermatologist. See also * Pemphigus * List of target antigens in pemphigus * List of cond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmosomes
A desmosome (; "binding body"), also known as a macula adherens (plural: maculae adherentes) (Latin for ''adhering spot''), is a cell structure specialized for cell-to-cell adhesion. A type of junctional complex, they are localized spot-like adhesions randomly arranged on the lateral sides of plasma membranes. Desmosomes are one of the stronger cell-to-cell adhesion types and are found in tissue that experience intense mechanical stress, such as cardiac muscle tissue, bladder tissue, gastrointestinal mucosa, and epithelia. Structure Desmosomes are composed of desmosome-intermediate filament complexes (DIFCs), a network of cadherin proteins, linker proteins and intermediate filaments. The DIFCs can be broken into three regions: the extracellular core region ("desmoglea"), the outer dense plaque (ODP), and the inner dense plaque (IDP). The extracellular core region, approximately 34 nm in length, contains desmoglein and desmocollin, which are in the cadherin family of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blister
A blister is a small pocket of body fluid (lymph, serum, plasma, blood, or pus) within the upper layers of the skin, usually caused by forceful rubbing (friction), burning, freezing, chemical exposure or infection. Most blisters are filled with a clear fluid, either serum or plasma. However, blisters can be filled with blood (known as "blood blisters") or with pus (for instance, if they become infected). Smaller blisters are called ''blebs''. The word "blister" entered English in the 14th century. It came from the Middle Dutch and was a modification of the Old French , which meant a leprous nodule—a rise in the skin due to leprosy. In dermatology, the words cutaneous condition#Vesicle, ''vesicle'' and ''bulla'' refer to blisters of smaller or greater size, respectively. Some sources recommend not to pop a blister. If popped, bacteria can enter. Excess skin should not necessarily be removed as the top layer protects the soft tissue underneath. However, some sources a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desmoglein 1
Desmoglein-1 is a protein that in humans is encoded by the ''DSG1'' gene. Desmoglein-1 is expressed everywhere in the skin epidermis, but mainly it is expressed in the superficial upper layers of the skin epidermis. Function Desmosomes are cell-cell junctions between epithelial, myocardial and certain other cell types. Desmoglein-1 is a calcium-binding transmembrane glycoprotein component of desmosomes in vertebrate epithelial cells. Currently, four desmoglein subfamily members have been identified and all are members of the cadherin cell adhesion molecule superfamily. These desmoglein gene family members are located in a cluster on chromosome 18. The protein encoded by this gene has been identified as the autoantigen of the autoimmune skin blistering disease pemphigus foliaceus. It has been found that desmoglein-1 is the target antigen in majority of the cases linked to IgG/IgA pemphigus, which is an autoimmune IgG/ IgA antibody mediated response. Desmoglein-1 is also a ta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
