Preparation and partial characterization of sheep erythrocyte-antibody-complement intermediate

Abstract

A reagent has been prepared which contains C′₄, C′₂, C′₃, C′₅, C′₆ and C′₇ by chromatography of guinea-pig serum on CM-cellulose. With this reagent, when supplemented with additional C′₅, EAC′_{1a,4,2a,3,5,6,7} was prepared from EAC′_1a. The reactivity and stability of cells possessing active C′₇ sites prepared with this reagent appeared to be the same as EAC′_{1a,4,2a,3,5,6,7} prepared from EAC′_1a,4 and mixtures of individual functionally pure components. The reactivity of cells possessing active C′₇ sites has been measured by initial velocity of generation of C′₈ sites, and an inhibitor of this reaction, Antrypol, has been described. A method for the estimation of the average number of C′₇ sites was investigated and a correlation appears to exist between the average number of sites per cell and the initial velocity of reaction with C′₈. Finally, a provisional method for the assay of C′₈ and C′₉ has been described.