[Immunostimulator CH2a bearing thiazolidin-4-one promotes the function of human iNKT cells in vitro].

OBJECTIVE:To explore the immunostimulatory effect of immunostimulant CH2a bearing thiazolidin-4-one on human invariant natural killer T (iNKT) cell function in vitro. METHODS:Peripheral blood mononuclear cells (PBMCs) were obtained from healthy adults, and then amplified with α-Galcer and IL-2 in vitro. The iNKT cells were isolated from these proliferating cells by magnetic-activated cell sorting (MACS) method. The purified iNKT cells were labled with 5-(and 6)-carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) and then incubated with CH2a for functional analysis, including cell proliferation, expressions of IFN-γ and IL-4 by flow cytometry, proliferation rate and cytotoxicity by MTT assay. In additon, ELISA was performed to determine the levels of IFN-γ and IL-4 in cell culture media. RESULTS:CH2a significantly promoted the proliferation of iNKT cells induced by IL-2 in vitro, stimulated the release of both IFN-r and IL-4, and led to the increase in IFN-γ/IL-4 ratio. More importantly, the cytotoxicity of iNKT was also markedly elevated under the stimulation of CH2a. CONCLUSION:Immunostimulant CH2a probably promote the production of Th1-like cytokines and the differentiation of Th0 to Th1, so as to improve cellular immune function. In addition, CH2a could significantly enhance the cytotoxicity of iNKT cells.