Studies of Antipneumococcal Serum

[摘要] The complement-fixing activities of fractions of one pooled normal and three pooled antipneumococcal rabbit sera (types 2, 3, and 7) have been studied quantitatively in the presence and absence of homologous type-specific carbohydrate antigen.Considered in relation to total nitrogen content, the water-insoluble globulin was, of these fractions, the most anticomplementary; the concentrated water-soluble globulin fraction had about the same degree of anticomplementary activity as the original serum; the albumin fraction had a negligible effect on complement.In titrations of the activities of the various fractions of antipneumococcal sera with homologous type-specific carbohydrate, a somewhat better agreement was noted between W , the maximally reactive dose of antigen, and η, the amount of antibody nitrogen present, than between η and K' , the number of units of complement required for 50-per-cent hemolysis. Although individual preparations differed in this respect, this observation suggested that the procedures of fractionation might have affected the combining activity of antibody with antigen less than its complement-fixing capacity in the presence of the same antigen.

[学科分类] 生物科学（综合）