title: Immunosuppressive effect of FK506 on collagen-induced arthritis in rats.
abstract: FK506, a new immunosuppressive agent, was given intramuscularly to rats for 12 days, starting on the day of type II collagen immunization. FK506 in doses of 0.32 mg/kg or more suppressed arthritis and also suppressed humoral and skin test response to type II collagen. FK506 suppressed arthritis only when given during the afferent limbs of immune response (0-4 days), whereas the drug was only marginally effective when treatment was started during the efferent limbs of immune response (7-11 days). FK506-induced immunosuppression continued and/or was maintained throughout the experiments (50 days). These rats immunized with type II collagen and treated with FK506 failed to develop arthritis even following a secondary immunization 50 days later but were fully capable of developing experimental allergic encephalomyelitis. This result suggest that FK506-treated rats develop specific unresponsiveness toward the type II collagen. It is concluded that FK506 is a strong immunosuppressive drug on collagen-induced arthritis.
mesh_terms: D000818:Animals; D001168:Arthritis / Q000188:drug therapy* / Q000276:immunology; D001183:Arthus Reaction / Q000209:etiology; D001323:Autoantibodies / Q000096:biosynthesis; D001327:Autoimmune Diseases / Q000188:drug therapy* / Q000276:immunology; D003094:Collagen / Q000633:toxicity; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000209:etiology; D005260:Female; D006968:Hypersensitivity, Delayed / Q000209:etiology; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D011725:Pyridines / Q000627:therapeutic use; D051381:Rats; D011917:Rats, Inbred Lew; D016559:Tacrolimus
chemical_list: D001323:Autoantibodies; D007166:Immunosuppressive Agents; D011725:Pyridines; D003094:Collagen; D016559:Tacrolimus