A novel synthetic immunostimulator CHla containing thiazolidin-4-one enhances the function of human iNKT cells in vitro

Objective To investigate the immunoregulatory effects of a novel synthetic immunos- timulator CHla containing thiazolidin-4-one on the function of human iNKT（ invariant nature killer T） cells in vitro. Methods Peripheral blood mononuclear cells （PBMCs） from healthy adults were cultured with stim- ulation of c~-Galcer and IL-2 in vitro, and iNKT cells were then separated by using magnetic -activated cell sorting （MACS） method with iNKT isolation kit. The effects of CHla on the proliferation of iNKT cells were analyzed by using MTT assay, sl Cr release assay was used to evaluate the killing activity of iNKT cells to K562 cells. Fluorescence-activated cell sorting （FACS） was used to detect the proliferation of iNKT cells, as well as the production of IFN-γ/and IL-4. Results CHla was found to significantly stimulate the iNKT proliferation （ mainly up to 4-7 generations）, promote the secretion of both IFN-γ and IL-4, and increase the ratio of IFN-γ/IL-4. More importantly, CHla could markedly enhance the cytotoxieity of iNKT cells. Con- clusion Immunostimulator CHla could promote the production of Thl-like cytokines by iNKT cells and in- duce differentiation of Th0 to Thl cells. Moreover, CHla could significantly enhance the cytotoxicity of iNKT cells. Key words: iNKT cell;  MACS;  IFN-γ/;  IL-4;  Immunostimulator