title: A simple and sensitive method for measuring tumor-specific T cell cytotoxicity.
abstract: A simple and sensitive method to quantitatively measure the cytolytic effect of tumor-specific T killer cells is highly desirable for basic and clinical studies. Chromium (51Cr) release assay has been the "gold standard" for quantifying cytolytic activities of cytotoxic T lymphocytes (CTLs) against target cells and this method is still being used in many laboratories. However, a major drawback of this method is the use of radioactive materials, which is inconvenient to handle because of environmental safety concerns and expensive due to the short half-life of the isotope. Consequently, several nonradioactive methods have been reported recently. Here we report a new method that we recently developed for quantifying antigen-specific cytolytic activity of CTLs. This method fully exploits the high sensitivity and the relative simplicity of luciferase quantitative assay. We initially expected the released luciferase in the supernatant to be the adequate source for monitoring cell death. However, to our total surprise, incubation of these killer T cells with the tumor cell targets did not result in significant release of luciferase in the culture medium. Instead, we found that the remaining luciferase inside the cells could accurately reflect the overall cell viability.
authors.affiliation: Department of Biology and Biochemistry, University of Houston, Houston, Texas, United States of America.
authors.forename: Xinping
authors.initials: X
authors.lastname: Fu
authors.forename: Lihua
authors.initials: L
authors.lastname: Tao
authors.forename: Armando
authors.initials: A
authors.lastname: Rivera
authors.forename: Shana
authors.initials: S
authors.lastname: Williamson
authors.forename: Xiao-Tong
authors.initials: XT
authors.lastname: Song
authors.forename: Nabil
authors.initials: N
authors.lastname: Ahmed
authors.forename: Xiaoliu
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001681:Biological Assay / Q000379:methods*; D002470:Cell Survival / Q000235:genetics / Q000502:physiology; D006801:Humans; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000378:metabolism
chemical_list: D008156:Luciferases; D018719:Erb-b2 Receptor Tyrosine Kinases