INHIBITION OF COMPLEMENT BY A SUBSTANCE ISOLATED FROM HUMAN ERYTHROCYTES .I. EXTRACTION FROM HUMAN ERYTHROCYTE STROMATA

Extraction of human E stromata with n-butanol was used to isolate an inhibitor which was capable of interfering with complement mediated hemolysis of antibody sensitized sheep E. When the extraction process was carried out at a low ionic strength a single substance could be detected by agar gel electrophoresis. Re-extraction at a higher tonic stength caused an apparent separation of the material into two substances which were detectable by agar-gel electrophoresis. Evidence was presented which indicated the slowest migrating component was responsible for the inhibitory activity. Preparative block electrophoresis was used as means for partial purification of the inhibitory substance and preliminary physical-chemical characteristics were determined. © 1969.