Related Research Articles
Antinuclear antibodies are autoantibodies that bind to contents of the cell nucleus. In normal individuals, the immune system produces antibodies to foreign proteins (antigens) but not to human proteins (autoantigens). In some cases, antibodies to human antigens are produced.
Autoimmune hepatitis, formerly known as lupoid hepatitis, plasma cell hepatitis, or autoimmune chronic active hepatitis, is a chronic, autoimmune disease of the liver that occurs when the body's immune system attacks liver cells, causing the liver to be inflamed. Common initial symptoms may include fatigue, nausea, muscle aches, or weight loss or signs of acute liver inflammation including fever, jaundice, and right upper quadrant abdominal pain. Individuals with autoimmune hepatitis often have no initial symptoms and the disease may be detected by abnormal liver function tests and increased protein levels during routine bloodwork or the observation of an abnormal-looking liver during abdominal surgery.
Primary biliary cholangitis (PBC), previously known as primary biliary cirrhosis, is an autoimmune disease of the liver. It results from a slow, progressive destruction of the small bile ducts of the liver, causing bile and other toxins to build up in the liver, a condition called cholestasis. Further slow damage to the liver tissue can lead to scarring, fibrosis, and eventually cirrhosis.
Primary sclerosing cholangitis (PSC) is a long-term progressive disease of the liver and gallbladder characterized by inflammation and scarring of the bile ducts, which normally allow bile to drain from the gallbladder. Affected individuals may have no symptoms or may experience signs and symptoms of liver disease, such as yellow discoloration of the skin and eyes, itching, and abdominal pain.
Anti-neutrophil cytoplasmic antibodies (ANCAs) are a group of autoantibodies, mainly of the IgG type, against antigens in the cytoplasm of neutrophils and monocytes. They are detected as a blood test in a number of autoimmune disorders, but are particularly associated with systemic vasculitis, so called ANCA-associated vasculitides (AAV).
An autoantibody is an antibody produced by the immune system that is directed against one or more of the individual's own proteins. Many autoimmune diseases are associated with such antibodies.
Anti-mitochondrial antibodies (AMA) are autoantibodies, consisting of immunoglobulins formed against mitochondria, primarily the mitochondria in cells of the liver.
Dihydrolipoyl transacetylase is an enzyme component of the multienzyme pyruvate dehydrogenase complex. The pyruvate dehydrogenase complex is responsible for the pyruvate decarboxylation step that links glycolysis to the citric acid cycle. This involves the transformation of pyruvate from glycolysis into acetyl-CoA which is then used in the citric acid cycle to carry out cellular respiration.
Extractable nuclear antigens (ENAs) are over 100 different soluble cytoplasmic and nuclear antigens. They are known as "extractable" because they can be removed from cell nuclei using saline and represent six main proteins: Ro, La, Sm, RNP, Scl-70, Jo1. Most ENAs are part of spliceosomes or nucleosomes complexes and are a type of small nuclear ribonucleoprotein (snRNPS). The location in the nucleus and association with spliceosomes or nucleosomes results in these ENAs being associated with additional RNA and proteins such as polymerases. This quality of ENAs often makes it difficult to purify and quantify their presence for clinical use.
Anti-actin antibodies (AAA) are found at increased frequency in certain autoimmune diseases and may be of some diagnostic value.
Nuclear pore glycoprotein-210 (gp210) is an essential trafficking regulator in the eukaryotic nuclear pore complex. Gp-210 anchors the pore complex to the nuclear membrane. and protein tagging reveals its primarily located on the luminal side of double layer membrane at the pore. A single polypeptide motif of gp210 is responsible for sorting to nuclear membrane, and indicate the carboxyl tail of the protein is oriented toward the cytoplasmic side of the membrane.
Anti-centromere antibodies are autoantibodies specific to centromere and kinetochore function. They occur in some autoimmune diseases, frequently in limited systemic scleroderma, and occasionally in the diffuse form of scleroderma. They are rare in other rheumatic conditions and in healthy persons.
Anti-p62 antibodies (AP62A) are found in a primary biliary cirrhosis. The p62 protein is also more frequent in Stage IV primary biliary cirrhosis and is prognostic for severe disease. The autoantigen is the nucleoporin 62kDA protein.
Nuclear pore glycoprotein p62 is a protein complex associated with the nuclear envelope. The p62 protein remains associated with the nuclear pore complex-lamina fraction. p62 is synthesized as a soluble cytoplasmic precursor of 61 kDa followed by modification that involve addition of N-acetylglucosamine residues, followed by association with other complex proteins. In humans it is encoded by the NUP62 gene.
Anti-sp100 antibodies are found in association with primary biliary cirrhosis. The autoimmune target of anti-sp100 is the sp100 nuclear antigen which was identified by its association with primary biliary cirrhosis. 20-30% of patients with primary biliary cirrhosis have sp100 Abs. The sera of these patients exhibit a characteristic "nuclear dots" pattern in indirect immunofluorescence (IIF) on Hep-2 cells.
Sp100 nuclear antigen is an interferon stimulated antigen found in the cell nuclei of many human and higher animal cells. Autoantibodies directed against Sp100 are often found in patients with primary biliary cirrhosis. Histologically Sp100 'dots' regions of the cell nucleus. Viral infection and mitogens affect the expression of the Sp100 autoantigen. Cells grown in the presence of interferons revealed an increase both in size and number of the Sp100 protein-containing nuclear dots and increase the protein concentration. This raises "the question whether cytokine-mediated increase of Sp100 protein expression plays a role in induction of anti-Sp100 autoantibodies."
Nucleoporins are a family of proteins which are the constituent building blocks of the nuclear pore complex (NPC). The nuclear pore complex is a massive structure embedded in the nuclear envelope at sites where the inner and outer nuclear membranes fuse, forming a gateway that regulates the flow of macromolecules between the cell nucleus and the cytoplasm. Nuclear pores enable the passive and facilitated transport of molecules across the nuclear envelope. Nucleoporins, a family of around 30 proteins, are the main components of the nuclear pore complex in eukaryotic cells. Nucleoporin 62 is the most abundant member of this family. Nucleoporins are able to transport molecules across the nuclear envelope at a very high rate. A single NPC is able to transport 60,000 protein molecules across the nuclear envelope every minute.
Anti-thrombin antibodies are autoantibodies directed against thrombin that may constitute a fraction of lupus anticoagulant and are seen an increased levels in systemic lupus erythematosus.
Anti-histone antibodies are autoantibodies that are a subset of the anti-nuclear antibody family, which specifically target histone protein subunits or histone complexes. They were first reported by Henry Kunkel, H.R. Holman, and H.R.G. Dreicher in their studies of cellular causes of lupus erythematosus in 1959–60. Today, anti-histone antibodies are still used as a marker for systemic lupus erythematosus, but are also implicated in other autoimmune diseases like Sjögren syndrome, dermatomyositis, or rheumatoid arthritis. Anti-histone antibodies can be used as a marker for drug-induced lupus.
Anti-SSA autoantibodies are a type of anti-nuclear autoantibodies that are associated with many autoimmune diseases, such as systemic lupus erythematosus (SLE), SS/SLE overlap syndrome, subacute cutaneous lupus erythematosus (SCLE), neonatal lupus and primary biliary cirrhosis. They are often present in Sjögren's syndrome (SS). Additionally, Anti-Ro/SSA can be found in other autoimmune diseases such as systemic sclerosis (SSc), polymyositis/dermatomyositis (PM/DM), rheumatoid arthritis (RA), and mixed connective tissue disease (MCTD), and are also associated with heart arrhythmia.
References
- ↑ Courvalin JC, Lassoued K, Worman HJ, Blobel G (1990). "Identification and characterization of autoantibodies against the nuclear envelope lamin B receptor from patients with primary biliary cirrhosis". J. Exp. Med. 172 (3): 961–7. doi:10.1084/jem.172.3.961. PMC 2188537 . PMID 2167346.
- ↑ Nickowitz RE, Worman HJ (1993). "Autoantibodies from patients with primary biliary cirrhosis recognize a restricted region within the cytoplasmic tail of nuclear pore membrane glycoprotein Gp210". J. Exp. Med. 178 (6): 2237–42. doi:10.1084/jem.178.6.2237. PMC 2191303 . PMID 7504063.
- ↑ Itoh S, Ichida T, Yoshida T, et al. (1998). "Autoantibodies against a 210 kDa glycoprotein of the nuclear pore complex as a prognostic marker in patients with primary biliary cirrhosis". J. Gastroenterol. Hepatol. 13 (3): 257–65. doi:10.1111/j.1440-1746.1998.01553.x. PMID 9570238.
- ↑ Nakamura M, Shimizu-Yoshida Y, Takii Y, et al. (2005). "Antibody titer to gp210-C terminal peptide as a clinical parameter for monitoring primary biliary cirrhosis". J. Hepatol. 42 (3): 386–92. doi:10.1016/j.jhep.2004.11.016. PMID 15710222.
- ↑ Nakamura M, Takii Y, Ito M, et al. (2006). "Increased expression of nuclear envelope gp210 antigen in small bile ducts in primary biliary cirrhosis". J. Autoimmun. 26 (2): 138–45. doi:10.1016/j.jaut.2005.10.007. PMID 16337775.
- ↑ Nakamura M, Kondo H, Mori T, et al. (2007). "Anti-gp210 and anti-centromere antibodies are different risk factors for the progression of primary biliary cirrhosis". Hepatology. 45 (1): 118–27. doi: 10.1002/hep.21472 . PMID 17187436.