Quantitative nucleic acid changes during phytohaemagglutinin-induced lymphocyte transformation in vitro. Dependence of the response on phytohaemagglutinin/serum ratio

Abstract

Pig and human blood lymphocytes were grown in culture without replenishment of medium, and stimulated to transform by phytohemagglutinin. Quantitative nucleic acid changes during this process were used as an index of transformation. On the first day, cells attach to glass; then they detach and continue transforming. The degree of transformation is dependent on the phytohemagglutinin/ serum ratio, and is independent of cell concentration within the range of 0.5 x 106-2.0x 106 cells/ml. At low phytohemagglutinin/serum ratios there is no response; at high phytohemagglutinin/serum ratios, inhibition appears after the cells were cultured for a day.