HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Borsos, T. Articles by Mayer, M. M. Search for Related Content PubMed Articles by Borsos, T. Articles by Mayer, M. M.

Studies on the Second Component of Complement¹

I. The Reaction between EAC'1,4 and C'2: Evidence on the Single Site Mechanism of Immune Hemolysis and Determination of C'2 on a Molecular Basis^,2

From the Department of Microbiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland

Abstract

1. The conversion of EAC'1,4 to EAC'1,4,2 by purified C'2 has been investigated with respect to its kinetics and the principal factors influencing this reaction. A mathematical theory has been developed and its applicability evaluated.

2. From kinetic evidence and on the basis of titration data, the transformation of EAC'1,4 to EAC'1,4,2 has been shown to involve a single reaction step, which means that interaction of one SA₂C'1,4 site with C'2 converts a cell to the state EAC'1,4,2. It follows that hemolysis by antibody and complement is a one-hit or noncumulative process.

3. On the basis of these results a method has been developed for measurement of C'2 in molecular terms.

4. The limiting-component principle of Hegedus and Greiner has been shown to be invalid. The over-all "titer" of complement depends primarily on the supply of C'2, but the availability of C'1, C'4 and the C'3 factors also plays a role because their concentrations influence the efficiency with which C'2 is utilized.

Footnotes

¹ This work was supported in part by National Science Foundation Grant G6476, United States Public Health Service Grant E2566, and contract ONR 248(17) with the Office of Naval Research.

² A preliminary report of the present work was presented at the 1960 meeting of the Federated Societies for Experimental Biology and Medicine (Fed. Proc., 19: 75, 1960).

³ USPHS Post-Doctoral Research Fellow of the N.H.I. 1958–1960.

⁴ USPHS Senior Research Fellow.