Rheumatoid factor production and polyclonal non-antiviral antibody responses elicited by infection with common mouse...

Rheumatoid factor (RF) production and antibody responses directed against antigens unrelated to infectious agents were measured in the serum of 129/Sv mice infected with various viruses. Some of these viruses induced a polyclonal B lymphocyte activation reflected by the presence of serum antibodies reacting in ELISA with dinitrophenylated albumin and with transferrin, but failed significantly to trigger the production of RF capable of agglutinating IgG2a-coated latex particles. In contrast, high RF serum levels were detected only in mice infected with an intestinal agent which was not able to induce other non-antiviral antibody responses. This observation indicates that the strong RF production previously reported in 129/Sv mice is a phenomenon specifically elicited by infection with this particular intestinal agent that cannot be explained by mere polyclonal B lymphocyte activation similar to that induced by common viruses.