Effect of KE-298 on production of immunoglobulins and IgG- and IgM-rheumatoid factors by rheumatoid arthritis mononuclear cells.

The effects of new immunomodulators, KE-298, on the production of immunoglobulins and IgG- and IgM-rheumatoid factors (IgGRF, IgMRF) by mono-nuclear cells from patients with rheumatoid arthritis (RA) were studied.KE-298 at the concentrations ranging from 3.13 to 200 μg/ml inhibited IgG, IgM and IgA production and IgGRF and IgMRF production by RA mononuclear cells. Mean % inhibition for IgG, IgM, IgA, IgGRF and IgMRF by 100 μg/ml KE-298 was 38.3%, 43.8%, 40.4%, 73.8% and 50.3%, respectively. Since enhanced RF production by RA mononuclear cells has an immunopathogenetic role in RA, the inhibitory action of KE-298 on RF production by RA mononuclear cells may be one of the mechanisms by which KE-298 exerts clinical efficacy in RA patients.