Bovine complement: formation of a lytic system between heat-inactivated foetal calf serum and fractions from normal human serum.

Although heat-inactivated foetal calf serum is regularly used as an "inert" additive for culture media, reconstitution of complement activity occurred on the addition of fractions of human sera. The nature of these factors is discussed. Chicken erythrocytes (CRBC), the target cells used in the study, were directly shown to be susceptible to the lytic action of bovine serum, suggesting their potential use in the assay of bovine complement.