ASSESSMENT OF IMMUNOTOXICITY BY MULTIPARAMETER FLOW-CYTOMETRY

Flow cytometry is a unique technology useful in the examination of eff ects of immunotoxic agents on target cells of the immune system. The p urpose of this workshop was to provide an overview of the use of flow cytometry in new and established models of immunotoxicity, with emphas is on the potential applications, assay validation, and potential pitf alls. This overview begins with a discussion of methods useful in the assessment of Ca2+-dependent mechanisms of lymphoid cell activation in surface marker-defined human B cells, T cells, and monocytes. A discu ssion of the use of how cytometry in analysis of apoptosis is also pre sented in this paper. The second paper presents data on the developmen t and use of how cytometry as an alternative to a Cr-51 release assay for an assessment of cytotoxic T cell activation. The use of surface m arkers for characterizing and distinguishing the effects of chemical i rritants from sensitizers is next presented, followed by an overview o f the use of fluorescent probes to assess cell thiol status and overal l oxidant-induced injury to lymphoid cells. Finally, an interlaborator y study designed to compare and evaluate the use of flow cytometry pro cedures in rat splenic cell subtyping is presented. Overall, these stu dies demonstrate the utility of flow cytometry assays in immunotoxicol ogic research, but further efforts are needed in the validation of man y of these assays for routine use in immunotoxicologic testing. (C) 19 97 Society of Toxicology.