Courtesy of Phoenix Flow Systems
HL-60 cells stained with Phoenix FlowSystems' ABSOLUTE-S Kit.
In 1993, two novel approaches to the measurement of cellular proliferation were published that have become widely accepted alternatives to the [3H]-thymidine incorporation method. One method, based on studies originally presented in 1983 by Mosmann, repeats and confirms experiments studying the use of 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrasodium bromide (MTT) tetrazolium salt in cell proliferation assays.4,5 Mosmann's study measured both lymphocyte proliferation and the lytic/growth inhibitory activities of cytotoxic lymphokines on normal cells using MTT.4 The later work showed that the MTT assay is a viable alternative to the [3H]-thymidine incorporation assay.5 The second method, published by Crouch and coworkers, demonstrates the use of adenosine triphosphate (ATP) bioluminescence as an indicator of increased cell number.6