The mitochondrial cytotoxicity assay (MTT) was the first widely accepted method to replace the radioactive thymidine incorporation assay for measuring cell proliferation. It was established by Mosmann in 1983 in his study: Mosman, T. (1983) A rapid colorimetric assay for cell growth and survival: application to proliferation and cytotoxicity. J. Immunol. Methods, 65, 55-63.