What is RP155 antibody?

What is RP155 antibody?

Autoantibodies (DNA directed) against the RP155 subunit (POLR3A) of RNA polymerase III can be detected by enzyme immunoassays. Results may be interpreted by humans or automated methods and used for the diagnosis of system sclerosis (SSc, diffuse and limited forms) and overlapping syndromes.

What does SCL 70 stand for?

The etymology of scl-70 consists of an abbreviation of scleroderma and a 70 kD extractable immunoreactive fragment that can be obtained from the otherwise larger (100–105 kD) target topoisomerase antigen (called the SCL-70 Antigen) of the antibodies.

What is SCL 70 IGG antibodies?

Autoantibodies against topoisomerase I (anti-Scl 70 antibodies) are the typical serologic marker of diffuse cutaneous systemic sclerosis (dcSSc). Systemic sclerosis (SSc) is a connective tissue disease characterized by microvascular damage and fibrosis of the skin and visceral organs.

What is progressive scleroderma?

Progressive systemic sclerosis (PSS), or scleroderma, is a rare disease characterized by excessive collagen deposition, mainly in skin, but also in other organs, and progressive vasculopathy. It is considered an autoimmune disease because of the presence of autoantibodies, several of which act against nuclear epitopes.

Is scleroderma always fatal?

It is the most fatal of all the rheumatologic diseases. Systemic scleroderma is very unpredictable although most cases can be classified into one of four different general patterns of disease (see Classification).

Can you have SCL 70 antibodies and not have scleroderma?

Serum anti-topoisomerase, also known as SCL-70, is specific to diffuse scleroderma (and the test is positive in 20% of people with scleroderma). Two-thirds of patients with this antibody have diffuse scleroderma.

What is the normal range for SCL 70?

The upper limit of normal for the Test-Scl-70 ELISA was established with 50 randomly chosen BBD sera by the percentile ranking method (28) at 32 units/ml, for a disease specificity of 100% (28) (the mean + 3SD was 26 units/ml).

What is the life expectancy of a person with scleroderma?

People who have localized scleroderma may live an uninterrupted life with only minor symptom experiences and management. On the other hand, those diagnosed with an advanced and systemic version of the disease have a prognosis of anywhere from three to 15 years.

How are anti-topoisomerase antibodies classified?

Anti-topoisomerase antibodies can be classified according to their immunoglobulin class (IgM, IgG or IgA). IgG-ATA is found most frequently in scleroderma, with IgA being quite common but IgM very infrequent.

How does ATA inhibit the activity of topoisomerase I?

Topoisomerase I is an enzyme that relaxes the strain on DNA by nicking and ligating the DNA. ATA inhibits the activity of this enzyme. Since this activity occurs in the nucleus of the cell ATA is a form of anti-nuclear antibody.

How are anti‐topo I antibody levels measured?

Anti‐topo I antibody levels were measured with specific ELISAs (Medical & Biological Laboratories, Nagoya, Japan). The human topo I protein (amino acids 163–765) was expressed as a β‐ d ‐galactosidase fusion protein using the pEX expression vector system.

Is DNA topoisomerase I an intracellular target for RNA polymerases?

DNA topoisomerase I (topo I), centromere proteins, RNA polymerases I, II and III and some nucleolar components have been identified as intracellular targets of ANAs [ 1 ].