Induced autoantibodies to fetal erythroid antigens in the chicken

Cornell Obese (OS) (B13B13), Special C (Sp.C) (B13B13) and K-strain White Leghorn chickens (B15B15) were examined for both naturally occurring and induced autoantibodies directed against erythroid fetal antigens. Obese chickens have been reported to produce high levels of autoantibodies to thyroglobulin and to occasionally produce antinuclear autoantibodies specific for erythrocytes. Despite producing high levels of antithyroglobulin autoantibodies and antibodies cross-reactive with erythrocytes, no OS chickens were found to possess naturally occurring autoantibodies to fetal-specific antigens on erythrocytes. However, such antibodies were induced following immunization with fetal erythrocytes derived from a strain allogeneic for the major histocompatibility complex (MHC), the B-complex. Challenge with both intact erythrocytes and erythroid membranes in Freund's complete adjuvant resulted in production of antibodies specific for fetal antigens. The ability to induce autoantibodies to fetal erythrocytes was not restricted to the OS-strain; similar antibodies were detected in the Cornell K-strain and Special C-strain chickens even when intrastrain immunizations were employed. These results suggest that antibodies can be induced to fetal antigens on chicken erythrocytes in both autoimmune and normal chickens given the appropriate antigen presentation.