Comparative cytotoxicity of purified Shiga-like toxin-IIe on porcine and bovine aortic endothelial and human colonic adenocarcinoma cells.

Porcine and bovine aortic endothelial cells and human colonic adenocarcinoma cells were compared for their susceptibility to the toxic effect of purified Shiga-like toxin IIe (SLT-IIe), measured by the neutral red cytotoxicity assay. Cytotoxicity correlated with toxin binding as indicated by fluorescence activated cell sorter analysis and with the globotriosylceramide (Gb3) and globotetraosylceramide (Gb4) content of cells determined by high pressure liquid chromatography. One line of porcine aortic endothelial cells was 1400-fold more susceptible than the line of bovine aortic endothelial cells that was tested, but a second line of porcine aortic endothelial cells was highly refractory to SLT-IIe. Human colonic adenocarcinoma cells lacked detectable levels of Gb4 and were least susceptible to SLT-IIe.