Objective: To investigate the proliferation of type II collagen specific T cell response and antibody formation in rheumatoid arthritis (RA) and their relations to HLA-DR4 subtype.
Methods: Peripheral blood mononuclear cells and serum were obtained from 62 RA patients, 14 males and 48 females, aged 43 +/- 29. CII263-272 decapeptide and the peripheral blood mononuclear cells (PBMCs) from 62 RA patients were co-incubated for 5 approximately 7 days. MTT method was used to examine the T cell proliferation. The serum antibodies specific to CII 263-272 were examined by ELISA. HLA-DR typing was detected in 40 patients by SSP-PCR.
Results: Positive T cell response challenged by CII 263-272 decapeptide was observed in 38 (61.3%) RA patients. The positive rate of CII 263-272 antibody was 66.7% in the T cell response positive group, significantly higher than that of the T cell response negative group (34.6%, P < 0.05). The T cell response rate of the CII 263-272 antibody positive group was 69.7%, significant higher than that of the negative group (42.1%, P < 0.05). In all patients, the stimulation index (SI) of T cell proliferation to CII263-272 peptide was positively correlated with the level of antibody (r = 0.68, P < 0.01). HLA-DR4 allele was detected in 16 out of the 40 patients. Positive T cell response and presence of antibody to CII 263-272 were not associated with HLA-DR4 phenotype.
Conclusion: The formation of CII antibody may be related to B cell activation mediated by CII specific T cell.