Objective: To investigate the relationship between HLA-DR4/1 subtypes and T cell response to influenza virus hemagglutinin (HA) as well as anti-HA308-317 antibodies in rheumatoid arthritis (RA).
Methods: The peripheral blood mononuclear cells (PBMCs) from 70 RA patients were cultured with HA308-317 for 5 days. T cell proliferative responses to HA308-317 were evaluated by [3H] thymidine incorporation assay. ELISA was used to detect the antibodies to HA308-317. HLA-DR4/1 subtypes were analyzed by PCR with sequence-specific primers.
Results: Twenty-seven of the 70 RA patients (38.6%) were positive for HLA-DR4/1 subtypes and 43 patients (61.4%) were negative for HLA-DR4/1 subtypes. In the HLA-DR4/1 positive group, T cell proliferative response to HA308-317 was observed in 17 (62.9%) RA patients and anti-HA308-317 antibodies were present in 15 RA patients (55.6%). In the HLA-DR4/1 negative group, T cell proliferative response to HA308-317 was observed in 10 (23.3%) patients and anti-HA308-317 antibodies were present in 25 (58.1% ) patients. T cell proliferative response to HA308-317 in the HLA-DR4/1 positive group was higher than in the negative group (P<0.01). However, there was no significant difference in production of antibodies to HA308-317 between the HLA-DR4/1 positive and negative groups (P>0.05).
Conclusion: There is a relationship between HLA-DR4/1 subtypes and T cell response to HA308-317. Antibodies to HA308-317 are not associated with HLA-DR4/1 phenotype. HA308-317 peptide may be involved in the pathogenesis of RA through activating HLA-DR4/1 specific T cells.