Effects of deoxyspergualin on collagen arthritis in mice

We have studied the effect of the immunosuppressive agent deoxyspergualin (DSG) on collagen arthritis in mice. DSG, when given prophylactically, was capable of suppressing the development of collagen arthritis in mice as well as the immunological response to native type II collagen in a dose-dependent manner. Further, treatment of DSG, started 7 days after the primary immunization, also resulted in the inhibition of development of arthritis and immunity to collagen. The treatment of DSG, started after a booster injection, did not suppress the development of arthritis, despite suppression of antibody production in collagen. These findings suggest the possibility that a threshold level of anti-type II collagen antibodies may exist which must be exceeded before arthritis develops. Its therapeutic use in mice did not affect the clinical course of arthritis or the immune response to collagen, which is similar to the results obtained with cyclosporin.