C1q: Isolation from human serum in high yield by affinity chromatography and development of a highly sensitive hemolytic assay

摘要: A C1q-depleted reagent (C1qD) was obtained from the nonadsorbed protein containing fractions of human IgG-Sepharose 4B affinity column and utilized in conjunction with sensitized sheep erythrocytes (EA) for detection quantitation C1q hemolytic activity. Employing optimal quantities C1qD assay mixture, highly purified preparations contained 0.5 to 1 × 1013 effective molecules/mg 1012 molecules/ml serum. This would therefore reproducibly detect less than ng