Human alpha-interferon enhances in vitro IgM rheumatoid factor synthesis by lymphocytes from normal subjects and...

Alpha-interferon (alpha-IFN) was added to pokeweed mitogen (PWM) or Epstein-Barr virus stimulated human peripheral blood mononuclear cell cultures from normal subjects or patients with rheumatoid arthritis (RA). Alpha-IFN enhanced in vitro production of PWM induced IgG and IgM, and significantly enhanced PWM induced IgM rheumatoid factor (IgM-RF) production by lymphocytes both from normal subjects and RA patients. Enhancement was recorded whether cells were preincubated with alpha-IFN for 16 hours or with alpha-IFN present throughout the culture period. Alpha-IFN did not enhance IgM-RF production in the absence of PWM or T cells. Enhancement of IgM-RF production was not seen in Epstein-Barr virus stimulated cultures.