Comparison of human and mouse PBMC sensitivity to LLO cytotoxicity. Results of purified LLO cytotoxicity tested on human and mouse PBMC (1 × 106/ml) in RPMI 1640 containing 4% NCS with PI. The percentage of living cells is shown. LLO concentration dependence was compared. Median values; P25 and P75, n = 3, p < 0.005.