Deficient control of in vitro Epstein-Barr virus infection in patients with ankylosing spondylitis.

Infectious Epstein-Barr (EB) virus obtained from the B95-8 marmoset cell line was used to infect mononuclear cells from healthy controls and patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS), and outgrowth of B cells into lymphoblastoid cell lines was assessed by visual microscopy and uptake of tritiated thymidine over a 28 day period. When undiluted virus was used lymphocytes from both patients with AS and RA and from normal controls outgrew into lymphoblastoid cell lines (LCLs) by day 28 of culture. At dilutions of 1/10, 1/20, and 1/40, however, the control cells showed regression of proliferation at approximately day 14 of culture, whereas the cells from patients with AS and RA continued to proliferate and outgrew into LCLs (transformation scores of cells from patients with AS compared with controls at day 28 p less than 0.05 in all cases; thymidine uptake at a 1/40 dilution at day 28, patients with AS compared with controls p less than 0.01). Hence these results suggest that there is a defect in the cellular response to EB virus induced B cell proliferation in patients with AS similar to that seen with cells from RA donors.