Figure 4. Scatterplot of NDV-LS cytotoxicity in normal control human cell lines in the presence of acetylated trypsin (n ranged from 10 to 19). The mean minimum cytotoxic doses for each cell type were high (ranging from 252 to 729) and are shown as horizontal lines here. HEKn cells were killed by acetylated trypsin alone so NDV cytotoxicity could not be determined in its presence.