A Modified MTS Proliferation Assay for Suspended Cells to Avoid the Interference by Hydralazine and beta-Mercaptoethanol

Abstract

The 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay is one of the most commonly used tests of cell proliferation. Hydralazine has been reported to interfere with the performance of the MTS assay when used on adherent cells. This study aimed to investigate whether hydralazine interferes with the performance of the MTS assay on suspended cells. THP-1 (a monocytic leukemia cell line) cells were cultured in the presence or absence of hydralazine (0, 10, 50, 100, and 500 μM) for 2 or 24 h. Cell numbers were analyzed using the MTS, trypan blue exclusion, or microscopic assays. A modified version of the standard MTS assay was established by centr..