title: Agonist-like autoantibodies against calcium channel in patients with dilated cardiomyopathy.
abstract: The calcium channel may be an important target in the autoimmune pathogenesis of dilated cardiomyopathy (DCM). The presence and function of serum autoantibodies against calcium channels (CC-AAbs) in patients with DCM were studied. Calcium-channel AAbs were detected in 80 patients with DCM and 80 controls by enzyme-linked immunosorbent assay (ELISA). Calcium-channel AAbs were further purified by affinity chromatography for characterization by immunoblotting and immunofluorescence. Voltage-clamp experiments were performed to identify the function of CC-AAbs. The presence of CC-AAbs was shown effectively by ELISA, and CC-AAbs were able specifically to bind to the calcium channel on the myocyte, confirmed by immunoblotting and immunofluorescence. Calcium currents were enhanced by CC-AAbs on Xenopus oocytes expressing human Ca(V)1.2 channels, which suggested CC-AAbs in patients with DCM were agonist-like. Our results suggest there are novel agonist-like CC-AAbs in patients with DCM. Calcium-channel AAbs might play an important role in the pathogenesis of DCM.
authors.affiliation: Laboratory of Cardiovascular Immunology, Key Laboratory of Biological Targeted Therapy of the Ministry of Education, Institute of Cardiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jie-Fang Avenue, 430022 Wuhan, Hubei, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Xiao
authors.forename: Min
authors.initials: M
authors.lastname: Wang
authors.forename: Yimei
authors.initials: Y
authors.lastname: Du
authors.forename: Jing
authors.initials: J
authors.lastname: Yuan
authors.forename: Guanghong
authors.initials: G
authors.lastname: Zhao
authors.forename: Danna
authors.initials: D
authors.lastname: Tu
authors.forename: Yu-Hua
authors.initials: YH
authors.lastname: Liao
mesh_terms: D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D015220:Calcium Channels / Q000276:immunology* / Q000378:metabolism; D002311:Cardiomyopathy, Dilated / Q000097:blood / Q000276:immunology*; D002846:Chromatography, Affinity; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005455:Fluorescent Antibody Technique; D005500:Follow-Up Studies; D006801:Humans; D015151:Immunoblotting; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
chemical_list: D001323:Autoantibodies; D015220:Calcium Channels