MTT Assay - MTT Assays Significance

MTT Assays Significance

Tetrazolium dye reduction is dependent on NAD(P)H-dependent oxidoreductase enzymes largely in the cytosolic compartment of the cell. Therefore, reduction of MTT and other tetrazolium dyes increases with cellular metabolic activity due to elevated NAD(P)H flux. Resting cells such as thymocytes and splenocytes that are viable but metabolically quiet reduce very little MTT. In contrast, rapidly dividing cells exhibit high rates of MTT reduction. It is important to keep in mind that assay conditions can alter metabolic activity and thus tetrazolium dye reduction without affecting cell viability and that different tetarazolium dyes will give different results depending on whether they are reduced intracellularly (MTT, MTS) or extracellularly (WST-1).