Serological and Physicochemical Reactivity of Bovine Erythrocytes before and after Trypsin Treatment

Abstract

On partition in aqueous polymer 2-phase systems containing dextran, poly(ethyleneglycol) (PEG) and PEG substituted with charged or hydrophobic groups, inagglutinable ox erythrocytes showed more negative surface charge and less hydrophobicity than agglutinable ox erythrocytes. Trypsin treatment of the erythrocytes increased the agglutinability, reduced the negative charge and seemed to increase the liability to hydrophobic interaction. Hemagglutination of highly negatively charged ox erythrocytes is almost impossible to accomplish by antibody against the ox erythrocytes alone or against IgG antigen linked to the erythrocytes in passive hemagglutination. Reverse passive (antiglobulin) hemagglutination cannot be accomplished with these cells when Ig antigens of moderate molecular size (.ltoreq. 900,000) are used. These cells may be agglutinated when a non-charged carrier such as a bacterium [Brucella abortus] coated with sensitizing antibody (Ig) is used to bridge the antiglobulin-coupled erythrocytes in a mixed lattice agglutinate. Such a bridging can also be accomplished by heat aggregation of the Ig antigen.