Acetylcholine Receptor-Ab (ARAb) RRA

The Acetylcholine Receptor-Ab RRA for 30 determinations is still available for sales! Please contact us for further information and a respective offer for the kit.

Radio receptor assay (RRA) for the in-vitro-diagnostic semi-quantitative determination of autoantibodies against the acetylcholine receptor in human serum and plasma. The measurement of highly specific autoantibodies against the acetylcholine receptor (AChr) supports the diagnosis of myasthenia gravis (MG), a rare but long-term muscle disease leading to muscle weakness of varying severity. The muscles of the eyes, face and for swallowing are most commonly affected. In diagnostics, the determination of autoantibodies against the acetylcholine receptor is used as the first serological tool in patients with suspected myasthenia gravis disease. AChR antibodies are directly pathogenic through crosslinking of AChRs following accelerated receptor degradation. Furthermore pathogenic function by inducing AChR conformational changes or blocking acetylcholine binding can be observed. A distinction is made between several forms of myasthenia gravis, for example generalized myasthenia gravis or ocular myasthenia gravis. Autoantibodies against AChR are detectable in serum of at least 80 % of patients with generalized myasthenia gravis and in 50-60 % of patients with ocular myasthenia. The examination of patients with suspected MG disease is usually performed with multiple antibody determinations. In the case of AChR seronegativity, the presence of other antibodies such as those against MuSK or Lrp4 can support diagnosis of an existing MG disease in AChR-seronegative patients. The most sensitive and specific AChR antibody test is a radioimmunoassay (binding antibody assay) using human AChR. It has been the gold standard for MG diagnosis for many years due to its high specificity and sensitivity.