High-sensitivity cytotoxicity assays for nonadherent cells.
High-sensitivity cytotoxicity assays refer to assays that can detect high levels of cell kill, to many powers of 10, and that can detect, ideally, a single remaining viable cell. Two such assays are described here, which have been used with Raji B-lymphoma cells, and are applicable to other nonadherent target cells. The first is a cell-counting assay, performed over a 3-wk period, which provides a simple, reliable, and sensitive assay of cytotoxicity. By determining the time required for 16-fold multiplication, the apparent fraction surviving can be calculated. This assay does not correct for treatment-induced delays in cell division and is dependent on maintaining the cells in exponential growth. The second assay measures colony-forming units using a limiting dilution method. Feeder cells are required to obtain a high cloning efficiency. Each dilution is plated in 48 wells of a 96-well plate, and positive wells are scored rapidly, by eye, after two wk.
Jules Mattes
M
M
Center for Molecular Medicine and Immunology, Belleville, NJ, USA.
D000906:Antibodies / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002452:Cell Count; D002470:Cell Survival / Q000187:drug effects; D003114:Colony-Forming Units Assay; D003601:Cytotoxicity Tests, Immunologic; D006801:Humans; D016393:Lymphoma, B-Cell; D011868:Radioisotopes / Q000494:pharmacology*; D014407:Tumor Cells, Cultured
D000906:Antibodies; D000970:Antineoplastic Agents; D011868:Radioisotopes