Production of Specific Anti-E Autoantibodies in Experimental Iso-immune Hæmolytic Anæsmia in Man

Abstract

IN 1961 we reported the results of studies on a case of acute, iso-immune hæmolytic anæmia experimentally induced in a C^wDe/Ce(R₁^wR₁) volunteer transfused with plasma containing exceptional anti-CD antibodies¹. Antibody sensitization of the recipient's erythrocytes was detected by the direct antiglobulin test (Coombs) up to day 133 following the plasma transfusion. Positive tests for antibody-coated red cells were obtained in the serum + albumin (a mixture of equal parts of human serum and 30 per cent bovine albumin) slide sensitization test through the 98th post-transfusion day. The study of the recipient's post-transfusion serum specimens for free, circulating antibodies in titration procedures employing serum + albumin revealed three distinct periods of antibody activity especially with the cDe/ce(R₀R₀) primary test cells. The first of these appearing between the first hour and the ninth post-transfusion day was interpreted as surplus antibodies remaining from those transfused in the anti-CD plasma, the second between post-transfusion days 14 and 98 as indicative of eluted or released antibodies and the final between days 105 and 140 as possible auto-immune antibodies representing the product of active immunization by the recipient himself. The peak titres of the free, circulating antibodies in the second and third periods of increased antibody activity were definitely higher than those obtained in the first, immediate post-transfusion one. In view of the Rh genotype of the recipient (C^wDe/Ce), the serologic specificity of the transfused antibodies (anti-CD) and the observation that the antibodies in the third peak were reactive against the C and D antigens in the Rh system, no conclusive proof of the auto-antibody nature of these antibodies could be established on the basis of blood group specificity.