Assay of anticomplementary activity in solutions of immunoglobulins.

ABSTRACT

A method of estimating the inactivation of complement by immunoglobulins, based on a hemolytic assay, is described. During a three year period of routine assays the investigation of standard immunoglobulin solutions of high and low anticomplementary activity confirmed the reliability of the method. Since the activity of complement is largely dependent on the ionic strength, the salt concentration of the test solution must be carefully adjusted. The specific complement inactivation per gram immunoglobulin CI50/g is proposed as a parameter to compare the anticomplementary activity of immunoglobulin solutions.