Research and development for regulating the Th17 responses by utilizing the adjuvant properties of human natural killer T cell subsets.

CD1d限制性不变NKT细胞在免疫应答、感染性疾病和肿瘤监测中发挥着重要作用。然而，NKT细胞发挥免疫调节功能的机制仍不清楚。在这项研究中，我们发现人NKT细胞的激活增强了IL-12p70，同时抑制了树突状细胞产生IL-23，进而下调了记忆CD4+Th细胞产生IL-17。提示NKT细胞通过改变IL-12p70/IL-23的平衡来增强细胞免疫功能，抑制IL-23依赖的炎性病变。

CD1d-restricted invariant NKT cells play crucial roles of immune responses, infectious diseases and tumor surveillance. However, the mechanisms by which NKT cells exert immune regulatory function remain elusive. In this study, we found that the activation of human NKT cells enhances IL-12p70 while inhibiting the IL-23 production by dendritic cells, in turn down-regulating the IL-17 production by memory CD4+ Th cells. This finding suggests that NKT cells modify the IL-12p70/IL-23 balance to enhance the cell-mediated immunity and suppress the IL-23-dependent inflammatory pathologies.