In vitro response of peripheral blood lymphocytes from patients with rheumatoid arthritis to lipopolysaccharides.

The effect of several LPSs on the thymidine uptake of lymphocytes from patients with RA was investigated. In contrast to normal controls, the mitogenic response to E. coli 026 B6 LPS by lymphocytes from patients with RA was significantly (2p less than 0.05) diminished. This effect was seen with Con A but not with PHA or PWM. No correlation with peripheral B or T cell percentages or with antibody titers to the LPS was found. The response to LPS was dependent on the species and strain of bacterium from which it was isolated.