The pathogenesis of chronic inflammation in experimental antigen‐induced arthritis. I. The role of antigen on the local immune response

Abstract

Abstract Using the model described by Dumonde and Glynn in which a chronic synovitis is induced by the intraarticular injection of antigen in previously immunized rabbits, marked chronic local synthesis of immunoglobulin comparable to that of lymph nodes and spleen was found as long as 6 weeks after the arthritis was induced. Between 30 and 40% of this newly synthesized immunoglobulin was accounted for as specific antibody to the locally injected antigen. Very low levels of synthesis were found in the spleen, control synovia and regional lymph nodes not draining immunized sites. The circulating antibody levels at the time of induction showed a positive correlation ( r = 0.66) with the severity of the subsequent histologic findings in the synovium. The fate of the intraarticular antigen was studied in arthritic and control animals. There was a selective local retention of antigen in animals previously immunized with the homologous antigen. The retained intraarticular antigen was eliminated very slowly, with a half‐life of over 20 days. These data indicate that the chronic synovial inflammatory response is associated with a chronic local immune response in which prolonged active synthesis of immunoglobulin and specific antibody directed against the locally retained inducing antigen takes place.