Use of a hapten-carrier system in experimental immune arthritis in the rabbit.

Animals immunized systemically with dinitrophenylated-bovine serum albumin (DNP-BSA) in complete Freund's adjuvant, show delayed hypersensitivity skin responses to DNP-BSA and to BSA, but not to other DNP-conjugates. These animals show high levels of antibodies to BSA and to DNP to radioimmunoassay. When injected with the carrier (BSA), the right knee joint develops a chronic arthritis. The left knee, when injected with the DNP hapten conjugated to another carrier (human serum albumin), shows an acute arthus response of the same magnitude as the right knee, but fails to develop a chronic synovitis. It appears that in this model, chronicity is not mediated primarily by a humoral mechanism to the initiator.