No abstract

Introduction. The investigations of Davidsohn (1, 2) have indicated, as suggested by Taniguchi (3), that human serum sickness following treatment with horse serum is heterophile in nature, and caused by the heterophile antigen naturally contained in horse serum. So far as we are aware other writers have not supported this point of view. In 1931, in testing out this hypothesis, we prepared mixtures of horse tetanus antitoxic globulin as well as other refined and whole horse antisera, and heterophile antibody derived from rabbits treated with boiled sheep erythrocytes. Ten to 20 units of heterophile antibody, as previously defined (4, 5, 6) were added to each cubic centimeter of the various horse sera, and the mixtures were allowed to stand for one week, alternating daily with room temperature and ice-box exposure. The precipitates which developed were removed by Berkefeld filtration, and the clarified mixed sera were found to contain from 2 to 5 units of heterophile antibody per cubic centimeter.