Acetylcholine receptor (AChR) antibodies
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Also known as |
Anti-AChR |
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Assay Information |
Autoantibodies to postsynaptic acetylcholine receptors are responsible for the muscle weakness and fatigabilities in myasthenia gravis. These antibodies are detectable in the serum of 80-90% of patients with generalized myasthenia gravis and in 55-70% of patients with ocular myasthenia. A good correlation is observed between antibody titres and muscle weakness in individual patients. The radio receptor assay for the determination of acetylcholine receptor antibodies in serum is highly specific and sensitive for use in the diagnosis of myasthenia gravis.
Acetylcholine receptor from human muscle is used as the antigen. The receptors are labelled with 125I-alpha-bungarotoxin.This snake venom binds the receptors most specifically and almost irreversibly. Autoantibodies present in the patient’s serum attach to the labelled receptors. The resulting immune complexes are subsequently precipitated with anti IgG. The amount of radioactivity in the precipitate is directly proportional to the concentration of acetylcholine receptor autoantibodies in the sample. |
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Specimen Type(s) & Minimum Volume |
Serum - 0.2mL |
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Cost |
£18.00
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Transport |
First class post
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Frequency of Analysis/Turnaround Time |
7 Working Days |
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Assay Method
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Radioimmunoassay
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Reference Range & Units |
< 2.5 X 10-10 mol/L Negative 2.5-4.0 X 10-10 mol/L Equivocal >4.0 X 10-10 mol/L Positive |
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Factors Affecting Performance of Examination
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Gross Haemolysis |
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Related Tests |
MuSK antibodies |
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Accredited Assay |
UKAS 8642
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External Quality Assurance (EQA) |
UKNEQAS for immunology scheme for acetyl choline receptor antibodies. IBL quality assessment scheme for acetylcholine receptor autoantibodies. INSTAND ev scheme for autoimmune diseases 10 |
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Further Information |
email: wcf-tr.neurobiochemistry@nhs.net
Telephone: 0151 5563262
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References |
Lindstrom J. (Clin. Immunol. Immunopathol. 1977; 7: 36 – 43) Vincent. A., Newsom-Davis. J. (Neurol. Neurosurg. & Psych. 1985; 48 1246 –1252) |
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Date last updated |
Tuesday, 17 August 2021 |
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