Autoantibodies recognizing proteins copurified with PCNA in patients with connective tissue diseases

作者：Takeuchi K^*; Kaneda K; Kawakami I; Takasaki Y; Hashimoto H

来源：Molecular Biology Reports, 1996, 23(3-4): 243-246.

DOI：10.1007/BF00351175

• proliferating cell nuclear antigen
• systemic lupus erythematosus

Objective. Proliferating cell nuclear antigen (PCNA), one of the target antigen recognized by lupus sera: has been reported to be present as a subnuclear multi-peptide complex. But autoantibodies reacting with components of PCNA complex are poorly understood. To study the specificity of those autoantibodies, immunoreactivities of autoimmune sera against purified PCNA antigen were studied. Methods. PCNA antigens were purified from rabbit thymus extract by affinity column using murine monoclonal antibodies (mAbs) to PCNA, TOB7, TO17 and TO30 Immunoreactivities of autoimmune sera against purified PCNA were analyzed by WE. Results. PCNA antigen purified by serum AK predominantly showed a 34 kD band specific for PCNA in SDS-PAGE. When antigens were purified by anti-PCNA mAb TOB7 and TO30 which are known to be targeting different epitopes on PCNA antigen, SDS-PAGE analysis showed various mel. wt of proteins in addition to the 34 kD PCNA while both AK and mAbs reacted only with 34 kD PCNA in WE. In WB using PCNA purified by TOB7, various immunoreactivities were observed at 150, 66, 58, 48, 45, 37, 32 and 16 kDa in sera from patients with connective tissue diseases. Conclusions. These results suggested that many of the proteins copurified with PCNA were also targets of autoimmune responses and these autoantibody expression may be induced through antigen-driven mechanisms.

• 出版日期1996