Quantitative comparison of techniques used to measure complement-mediated cytotoxicity of nucleated cells

?The cytotoxicity of nucleated cells by specific antibody and complement can be guantitated in vitro by several methods. Trypan blue exclusion, 51-Cr release, inhibition of uptake of 3-H-thymidine, and inhibition of colony formation are the four assays that we used to guantitatively compare the C-mediated cytotoxicity of Chinese hamster lung (CHL) cells. CHL cells were sensitized with either guinea pig or rabbit anti-CHL antisera, and exposed to guinea pig, human, or rabbit C. We found that the relative activities of the antibodies and the complements were not dependent on the method of measurement of cytotoxicity, i.e., a given pair of antiserum-complement were not dependent on the method of measurement of cytotoxicity, i.e., a given antiserum-complement titer, regardless of the assay used to measure cytotoxicity. However, the titers of the different antibody-complement pairs differed from each other.