Finally, in order to investigate the CMV response, we restimulated (4 hrs) PBMC from anti-CMV IgG seropositive RA patients with CMV lysate or control lysate and determined the CMV specific IFNγ production of CD4 SP T cells and CD4CD8 DP T cells by cytokine secretion assay. The gene discussed is CD4; the disease is rheumatoid arthritis.