PMID: 9436458Jan 22, 1998Paper

Molecular immunology of voltage-gated calcium channel and Lambert-Eaton myasthenic syndrome

Nihon rinsho. Japanese journal of clinical medicine
K IwasaM Takamori

Abstract

Lambert-Eaton myasthenic syndrome(LEMS), an autoimmune disease that is often associated with small cell lung carcinoma(SCLC), impairs the quantal release of acetylcholine by directing antibodies against voltage-gated calcium channels (VGCC) in the motor nerve terminal. We focused attention on the P/Q type VGCC, to which there are antibodies in LEMS patients in higher frequency than antibodies to other types of VGCC. To search for antigenic sites in the molecular structure of alpha 1A subuuit of P/Q type VGCC in LEMS, we synthesized 4 peptides corresponding to the extracellular region (S5-S6 linker) of each of 4 domains that form alpha 1A subunit of VGCC. Also, LEMS patients' sera were studied by immunoprecipitation assay using these antigens. Peptides corresponding to the extracellular region (S5-S6 linker) of domains II and IV were specifically reactive with LEMS antibodies; their titiers respectively correlated with those of anti-P/Q type calcium channel (omega-conotoxin MVIIC-sensitive human cerebellum extret). Lewis rats were immunized with the domain II S5-S6 linker peptides conjugated with KLH. The immunized rats showed LEMS features characterized by reduced acetylcholine quantum content of endplate potentials and antibod...Continue Reading

Related Concepts

Related Feeds

Autoimmune Diseases

Autoimmune diseases occur as a result of an attack by the immune system on the body’s own tissues resulting in damage and dysfunction. There are different types of autoimmune diseases, in which there is a complex and unknown interaction between genetics and the environment. Discover the latest research on autoimmune diseases here.