Comparison study on 3H-thymidine incorporation assay and MTT assay in the measurement of IL-2 activity =Interleukin-2 활성의 측정에 있어 3H-thymidine 흡수법과 tetrazolium-based(MTT) colorimetric assay

Abstract

Measurement of interIeukin-2 (IL-2) activity using 3H-thymidine incorporation assay has been considered to be a standard method. However, use of isotope in this assay system is one limitation in popular use of this method. In addition, multiple steps of cell transfer may be a cause of interexperimental data variation. We have compared the conventional 3H-thymidine incorporation assay with colorimetric assay utilizing tetrazolium-based compound (MTT) in the measurement of CTLL-2 cell proliferation response to IL-2 stimulation. Values of optical density (OD) of MTT were proportional to the cpm values of 3H-thymi-dine incorporation assay. Therefore, the MTT assay offers a valid, inexpensive and simple method to assess the number of CTLL-2 cells stimulated by IL-2.