期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1978
卷号:75
期号:8
页码:3953-3956
DOI:10.1073/pnas.75.8.3953
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Murine Ia and human DR antigens were isolated and purified by immunoprecipitation and sodium dodecyl sulfate/polyacrylamide gel electrophoresis with allo- and xenoantisera, respectively. The I-A subregion antigen consists of two chains, designated Aalpha and Abeta, with molecular weights of 35,000 and 26,000, respectively. The I-C subregion antigen likewise consists of two chains, designated Calpha and Cbeta, with molecular weights of 32,000 and 29,000, respectively. Under nonreducing conditions, the Cbeta chain migrates appreciably more rapidly on sodium dodecyl sulfate/polyacrylamide gels than the reduced Cbeta chain, reflecting the presence of an intrachain disulfide bond. The human DR antigen is also a two-chain unit and contains DRalpha and DRbeta components with molecular weights of 34,000 and 28,000, respectively. The DRbeta chain migrates more rapidly before reduction than afterward, like the murine Cbeta chain. The DRbeta and Cbeta chains are also strikingly homologous if a single amino acid shift is imposed on one of those chains. Thus, human DR antigens strongly resemble the murine I-C subregion antigens.