Kinetic Studies on Immune Hemolysis. V. Formation of the Complex EAC'x and Its Reaction with C'y1,2.

摘要

It has been shown in this laboratory that the accurate and precise action of complement (C') on sensitized erythrocytes (EA) takes place in at least 2 successive steps (1-3). The first of these requires Ca++ specifically and involves the fixation of certain components C', provisionally termed C'x, with formation of a complex EAC'x. In the second step, which necessitates Mg++, the complex EAC'x reacts with other components of complement, provisionally designated C'y. In the preceding paper of this series (4) it has been shown complex EAC', may he formed by treatment of EA with C' in the presence of Ca++, but absence of Mg++. Furthermore, it was demonstrated reagent containing C'y, but lacking C', may be prepared by treatment of C' with an unrelated specific precipitate (e.g., serum albumin-rabbit antibody) in the presence of change resin. Ca ++, but absence of Mg++. The C'y reagent is hemolytically inactive when added to EA, but upon admixture with cells in the state EAC', interaction ensues, provided Mg++ is available. A typical experiment, describing the reaction between EAC', and C'y was included in the the preceding paper. pg 1. JMD.