ANTIGENIC SPECIFICITIES ACQUIRED FROM THE GROWTH MEDIUM BY CELLS IN TISSUE CULTURE.

Studies employing quantitative complement fixation have shown that HeLa and other mammalian cells grown in tissue culture adsorb serum protein components from the growth medium. The serum proteins are not completely removed by vigorous washing. Upon injection of extensively washed cells into rabbits the bound serum proteins give rise to specific antibodies detectable by gel diffusion and complement fixation. With horse serum in the growth medium one of the cell-bound components was identified as horse γ globulin. Evidence was obtained that specific antibodies to bound serum antigens can contribute to complement-dependent kill of the cells . These observations suggest one possible mechanism for the acquisition of antigenic relationships by diverse cell lines grown in tissue culture.