Analysis of the responding and stimulating cells in the AMLR of patients with rheumatoid arthritis using limiting dilution.

Plastic adherent and non-adherent mononuclear cells derived from synovial fluid were found to stimulate peripheral blood mononuclear cells of patients with rheumatoid arthritis (RA) in an autologous mixed lymphocyte reaction (AMLR). Stimulation produced by adherent cells was consistently greater than that produced by non-adherent mononuclear cells. CD11 enriched cells were not significant stimulators in the AMLR, however their presence was required for a significant reaction to occur. Limiting dilution studies revealed that the most plausible model involved two or more cells of the same type in each of the stimulator and responder populations for the AMLR to occur.