Detection of dead cells and measurement of cell killing by flow cytometry

A flow cytometer can quickly perform numerous quantitative, sensitive measu rements on each individual cell within a large, heterogeneous population. T he modem commercially available analytical instruments, which can be found in most hospitals, pathology laboratories, and cell biology research labora tories in the industrially developed countries, can now routinely measure f luorescence simultaneously at four different wavelengths, in addition to li ght scatter in two directions, at rates of thousands of cells per second. T hus, flow cytometry provides a powerful and versatile approach to the measu rement of cell death and cell killing. However, it is important to stress t hat the biological nature of the phenomenon under investigation will determ ine which assay is appropriate, and at what stage in the process of cell ki lling it should be applied. This consideration is particularly important in the study of drug- or cell-mediated cytotoxicity. (C) 2000 Elsevier Scienc e B.V. All rights reserved.