Selective lymphocyte deficiency in seronegative rheumatoid arthritis.

Prior studies have shown that in vitro infection with the Epstein Barr virus (EBV) is able to induce IgM rheumatoid factor production by normal lymphocytes, with a higher degree of production by seropositive rheumatoid arthritis lymphocytes. The present investigation demonstrates that EBV-infected lymphocytes from patients with seronegative rheumatoid arthritis produce in vitro significantly less IgM rheumatoid factor than do normal lymphocytes. The results suggest that the peripheral blood of seronegative patients is deficient in the rheumatoid factor precursor B cells responsive to stimulation by Epstein Barr virus.