Abstract
Kidney and skin transplantation sera were studied for rheumatoid-like factors by the latex and agglutination test with erythrocytes sensitized by human or rabbit antibodies. Of 23 patients with kidney allografts, 9 developed serum factors combining with human [gamma]-globulin and 6 formed factors combining with both human and rabbit [gamma] -globulin after grafting. Of 46 recipients who rejected 3 successive skin allografts, 2 produced anti-human [gamma] -globulin factors and 7 formed anti-rabbit [gamma] -globulin factors. The anti- [gamma] -globulin activity of transplantation sera is associated with the YM class of immunoglobulins. The anti-human [gamma] -globulin factor not inhibited by the patient''s own pretransplantation serum was inhibited by pretransplantation sera of some other patients and normal human sera. In 1 instance, the donor''s serum was available; it failed to inhibit the activity of the recipient''s factor. Anti-rabbit [gamma] -globulin factors had somewhat different serological properties in sera of kidney graft and skin graft recipients. The possible mechanism of formation of the rheumatoid-like factors by allograft recipients was discussed.