Complement Components in Normal Serum and Plasma Quantitated by Electroimmunoassay

Abstract

The concentrations of Clq, Cls, C3, C4, C5, C3 proactivator, and Cl̄ inactivator in serum and EDTA plasma from 100 normal adults were determined by electroimmunoassay. The normal range of each of the proteins is given. The Clq values varied more closely with the Cls values than with the levels of the other complement components. C3, C5, and C3 proactivator seemed to form a fairly interdependent group. The reproducibility of double determinations (interplate variation) was 4.9% to 7.9%. The variation of the complement component levels on repeated sampling from normal individuals was investigated. Also, repeated freezing and thawing and storage at room temperature of serum and plasma were studied for their effect on the quantitation of the complement components. C3 and C4 values obtained by electroimmunoassay were in agreement with the values obtained by single radial immunodiffusion.