Presynaptic modification of neuromuscular transmission by antiacetylcholine receptor antibody: myasthenic serum and monoclonal antibody produced by transformed lymphocytes.
When myasthenic serum or a monoclonal antiacetylcholine receptor (anti-AChR) antibody produced by human transformed lymphocytes and transferable to an animal was applied to rat diaphragms in vitro, presynaptic facilitation was demonstrated by changes in ACh quantal content of endplate potentials. The results correlated with ability of the antibody to block binding of alpha-bungarotoxin to AChR, but not with titers of anti-AChR antibody by immunoprecipitation assay and AChR degradation rate. Antibody to the receptor site near the ACh-binding site may act presynaptically to compensate for the postsynaptic failure in myasthenia gravis.
D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000502:physiology*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D001666:Binding Sites, Antibody / Q000187:drug effects; D003964:Diaphragm / Q000187:drug effects* / Q000503:physiopathology; D004594:Electrophysiology; D005260:Female; D006801:Humans; D007074:Immunoglobulin G; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D008297:Male; D009157:Myasthenia Gravis / Q000097:blood*; D051381:Rats; D011917:Rats, Inbred Lew; D011919:Rats, Inbred Strains; D011950:Receptors, Cholinergic / Q000187:drug effects*
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D011950:Receptors, Cholinergic; D000109:Acetylcholine