Some observations on reversed anaphylaxis

Abstract

1. The symptoms and autopsy findings in guinea-pigs following intravenous injection of antisera prepared against guinea-pig serum or serum fractions are described. Two types of reaction were observed, acute and delayed, similar to those described in direct anaphylaxis.2. The alterations in systemic blood pressure, pulmonary arterial pressure, and bronchial resistance, were investigated and found to simulate closely those observable in ordinary anaphylactic shock.3. The antisera have the power of stimulating contraction of the isolated uterus of the guinea-pig, either in the presence or absence of excess guinea-pig serum. The reaction, like that observed in direct anaphylaxis, is therefore cellular.4. Antisera prepared against guinea-pig serum proteins contain, in addition to precipitins, agglutinins for the red cells of that species, and Forssmann antibody. Neither of the last two antibodies, however, is responsible for the shock phenomena here described. It appears that the potency of a serum to produce shock in guinea-pigs is dependent on several factors, of which the most important is the content in precipitins reacting with the guinea-pig serum proteins. These precipitins give rise to the reactions following intravenous injection into guinea-pigs, not merely as a result of humoral combination with homologous antigens, but largely, if not wholly, as the result of an immune reaction with antigens in the protoplasm of the tissue cells.