%0 Journal Article
%T Flowcytometry ¨C A rapid tool to correlate functional activities of human peripheral blood lymphocytes with their corresponding phenotypes after in vitro stimulation.
%A R Nirmala
%A PR Narayanan
%J BMC Immunology
%D 2002
%I BioMed Central
%R 10.1186/1471-2172-3-9
%X The results indicated that natural killer cells (NK) constituted the predominant proliferating cell population in the cytokine stimulatedcultures. Flowcytometric evidence revealed that CD56+ T cells contributed little to LAK activity against U937 target cells as compared to cells with NK phenotype which were predominantly responsible for spontaneous killing of the tumor targets. The two cytokines, IL-2 and IL-12, had an additive effect on cell proliferation and spontaneous cytotoxicity.Flowcytometry can be used to rapidly delineate phenotypic changes in immune cells after stimulation and simultaneously correlate them with corresponding functional activity. This approach may find application as a initial screening tool for studying different types of cells in mixed cultures and their respective activities under stimulatory / inhibitory conditions.The in vitro culture of human peripheral blood lymphocytes in IL-2 results in the generation of cytotoxic cells that lyse tumor targets. Natural Killer (NK) cells are the main lymphocytic population constitutively expressing p75¦Â chain of the IL-2 receptor and exhibiting up-regulation of LFA-1 (Lymphocyte Function associated Antigen-1) molecule upon IL-2 stimulation. Consequently, incubation of peripheral blood lymphocytes with IL-2 induces selective activation of NK cells, rapid increase of NK activity followed by generation of LAK activity and proliferation. This has been referred to as the LAK phenomenon[1]. Similarly IL-12 treatment of peripheral blood mononuclear cells (PBMC) or pure NK cells within a few hours, induces, an enhancement of cytotoxic ability. It was observed that the maximum enhancement obtained with IL-12 is less than that obtained with IL-2 and comparable to that observed with IFN-¦Ã. However, IL-12 was found to be effective at concentrations 2¨C3 order of magnitude lower than IL-2/IFN-¦Ã. Maximum enhancement of NK mediated cytotoxicity was observed with a combination of IL-12 and IL-2, the effect of the t
%U http://www.biomedcentral.com/1471-2172/3/9