Wang Rong-Fu, Peng Guangyong, Wang Helen Y
Center for Cell and Gene Therapy and Department of Immunology, Baylor College of Medicine, Houston, TX 77030, USA.
Semin Immunol. 2006 Apr;18(2):136-42. doi: 10.1016/j.smim.2006.01.008. Epub 2006 Feb 15.
Regulatory T (Treg) cells induce immune tolerance by suppressing host immune responses against self- or non-self-antigens, thus playing critical roles in preventing autoimmune diseases. However, tumor cells may take advantage of Treg cells to protect themselves from immune attack elicited by vaccines. Recent studies demonstrate the presence of Treg cells in various types of cancers and their suppressive function. Therefore, Treg cells at tumor sites have detrimental effects on immunotherapy directed to cancer and infectious diseases. This review will discuss antigen specificity of Treg cells, the factors that contribute to Treg cell generation and suppressive function, and their regulation through Toll-like receptor signaling. It was generally though that TLR-mediated recognition of specific structures of invading pathogens initiate innate as well as adaptive immune responses through dendritic cells. New evidence suggests that TLR signaling may directly regulate the suppressive function of Treg cells. Linking TLR signaling to the functional control of Treg cells opens intriguing opportunities to shift the balance between CD4(+) T-helper and Treg cells, in ways that may improve the outcome of cancer immunotherapy.
调节性T（Treg）细胞通过抑制宿主针对自身或非自身抗原的免疫反应来诱导免疫耐受，从而在预防自身免疫性疾病中发挥关键作用。然而，肿瘤细胞可能利用Treg细胞来保护自身免受疫苗引发的免疫攻击。最近的研究表明，各种类型的癌症中都存在Treg细胞及其抑制功能。因此，肿瘤部位的Treg细胞对针对癌症和传染病的免疫治疗具有不利影响。本综述将讨论Treg细胞的抗原特异性、促成Treg细胞生成和抑制功能的因素，以及它们通过Toll样受体信号传导的调节。人们普遍认为，Toll样受体（TLR）介导的对入侵病原体特定结构的识别通过树突状细胞启动先天性和适应性免疫反应。新证据表明，TLR信号传导可能直接调节Treg细胞的抑制功能。将TLR信号传导与Treg细胞的功能控制联系起来，为以可能改善癌症免疫治疗结果的方式改变CD4（+）辅助性T细胞和Treg细胞之间的平衡提供了有趣的机会。
