Cytokine production by helper T cell populations from the synovial fluid and blood in patients with rheumatoid arthritis.

OBJECTIVE

Our study was undertaken to determine the phenotypic changes and cytokine production from the synovial fluid (SF) and blood of patients with rheumatoid arthritis (RA).

METHODS

Blood and SF purified T cells were stained with monoclonal antibodies using standard, indirect immunofluorescence technique for the determination of T cell receptor (TcR) TcR alpha beta and TcR gamma delta antigen expressions, CD25, CD38, CD71, HLA-DR activation antigens, and for percentage distribution of CD4+CD29+ and CD4+CD45RA+ subsets. The production of interleukin 2 (IL-2), IL-4 and IL-6 by various T cell compartments was determined by the bioassay or enzyme linked immunosorbent assay methods.

RESULTS

Highly elevated percentage of CD3+TcR gamma delta and CD4+CD29+ T cell subsets were detected in SF and blood of RA. The CD4+CD29+ T cell subsets produced elevated levels of IL-4 and IL-6 but deficient levels of IL-2. IL-6 cytokine induced CD4+CD29+ subsets were found to provide effective helper function to B cells in IgG and IgM synthesis.

CONCLUSION

The IL-6 production and IL-6 induced CD4+CD29+ T cell subset function in B cell antibody synthesis may be important in B cell hyperactivity and antibody synthesis in RA. Our studies suggest that CD4+CD29+ subsets bearing TcR gamma delta antigens are increased at inflammation site (SF) in RA and is implicated in immunopathology and autoantibody production of this inflammatory condition in humans.