THE DETERIORATION OF COMPLEMENT ACTIVITY IN NORMAL HUMAN SERUM 1

Abstract

Standards of normal hemolytic complement activity in human serum are established by the method of Wads-worth, Maltaner and Maltaner. The median amt. of human blood serum required to produce 50% hemolysis of a standardization sheep red cell suspension is 0.0049 ml. The median is not significantly changed by age, sex, or a 48 hr. delay, at 6[degree]C, between the time of collecting and of testing. At refrigerator temp. (6[degree]C.), the median complement activity of specimens of human serum is reduced beyond the lower limits of normal in 11-13 days. The median decrease in this time interval is 44%. At room temp. (23 to 25[degree]C.), there is a similar reduction in 2 days. The decrease in complement activity after 48 hrs. at refrigerator temp. (6[degree]C.) was insignificant when compared to the previously reported relatively large decreases in complement activity occurring during pneumonia, during serum sickness, and when type-specific antipneumococcus horse and rabbit serum were administered intraven. to pneumonia patients.