Antigammaglobulin antibodies in experimental adjuvant arthritis.

Several-fold administration of complete Freund's adjuvant in rat provoked acute arthritis accompanied by production of antigammaglobulin antibodies in a high percentage from the animals studied; their sera precipitate homologous and heterologous aggregated IgG and demonstrate hemagglutination titers up to 1 : 1792. To confirm the Ig type of the studied antibodies, rat sera were fractionated by gel filtration on Sephadex G200 by pH = 4.0 and by preparative ultra-centrifugation by pH = 3.6. It was established that the antibodies are of IgM type. - The presence of autoantibodies in an autoimmune disease, such as experimental adjuvant arthritis similar to the rheumatoid factors in human rheumatoid arthritis gives support to the statement that autoimmune processes are involved in the etiology of rheumatoid arthritis in men.