Anticomplementary Effects and Complement Activity of Human Sera

Abstract

Conclusion The probit transformation for the plotting of immune hemolysis produced by measured amounts of fresh human serum was found to be suitable for titration of complement. Serum from a patient with a high level of C′ activity was found to become highly anticomplementary when heated to 56°C for 30 minutes, but inactivation by heating for 30 minutes at 52°C or below produced little anticomplementary activity in this serum. Addition of an equal quantity of 9% bovine serum albumin prior to heating also prevented the expression of the anticomplementary activity. Ability of serum to become highly anticomplementary as a result of heating is not necessarily associated with diminished activity of its endogenous complement. Conversely, sera with low levels of C′ may not become anticomplementary as a result of heating.