Specific White Cell Lysis Produced by Combination of Rabbit Antiserum to Purified Protein (Ovalbumin, Bovine Gamma Globulin) with Homologous Antigen. The Role of Non-Precipitating Antibody

Abstract

Specific white cell lysis is produced by the addition of homologous antigen to fresh heparinized blood of certain rabbits immunized with crystalline hen ovalbumin or with bovine gamma globulin (Armour's Fraction II). Specific lysis may be produced in white cells of fresh normal rabbit blood by the addition of antigen and the serum of a sensitized animal. There is an optimum concentration of antigen or range of antigen concentrations giving maximal lysis when the amount of antibody is constant. Dilution of antiserum results in a corresponding reduction in the amount of antigen producing maximal lysis and in a reduction of its lytic potency. Heating at 55–58 C for 4 hours failed to destroy the lytic capacity in 3 of 4 antisera tested. The cells affected by specific lysis were polymorphonuclear leukocytes in tests of 5 different antisera (platelets were not studied). The specific lytic capacity of an antiserum is not related to its content of precipitable antibody N or to its equivalence ratio R. No loss of lytic power results from removal of the precipitable antibody by small successive additions of antigen. Removal of all precipitable antibody by a single addition of antigen removed all lytic power from one of 2 sera so studied. Certain specifically lytic anti-ovalbumin sera showed lysis with an immunochemically uniform ovalbumin preparation and not with the common ovalbumin contaminants. These also showed a single band of precipitate by the Oudin agar diffusion technic, whereas certain nonlytic sera showed more than one band. White cell lytic power was moderately well correlated with the ability to give passively transferred urticarial reactions in human or guinea pig skin, but not with the ability to cause passive anaphylaxis in the guinea pig. Development of specifically lytic antibody was more evident in rabbits immunized by single intraperitoneal or intravenous doses of antigen in solution or repeated subcutaneous doses of alum-precipitated antigen than in rabbits receiving repeated subcutaneous or intravenous doses of antigen in solution.