Kim R, Emi M, Tanabe K
International Radiation Information Center, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan.
Clin Exp Immunol. 2006 Nov;146(2):189-96. doi: 10.1111/j.1365-2249.2006.03215.x.
Dendritic cells play a crucial role in initiating tumour immunity as well as in the immune response for invading foreign pathogens such as bacteria and viruses. For bacterial and viral infections, the immature dendritic cells (iDCs) residing in peripheral tissues are efficiently activated and matured by pathogen signals for performing the immune response. In contrast, for self-antigens, the naive T cells are not activated by iDCs but proceed to anergy/deletion, and the generation of regulatory T cells for immune tolerance. The induction of immune response and tolerance is regulated strictly by iDCs as the sensor for homeostasis of immune response in the host. Despite the identification of some tumour antigens, tumour immunity is not provoked successfully. Even though there are some critical obstacles to inhibit effective tumour immunity, tumour cells are able to exploit the functional roles of iDCs for tumour progression, which are induced by tumour-derived soluble factors such as vascular endothelial growth factor (VEGF) and functionally modulated in the microenvironment. The iDCs still remain as the critical target for provoking tumour immunity. In this review, the functional roles of tumour-associated iDCs and the strategy for targeting iDCs in effective tumour immunity for the cancer patient are discussed.
树突状细胞在启动肿瘤免疫以及针对入侵的外来病原体（如细菌和病毒）的免疫反应中发挥着关键作用。对于细菌和病毒感染，驻留在外周组织中的未成熟树突状细胞（iDCs）被病原体信号有效激活并成熟，以执行免疫反应。相比之下，对于自身抗原，幼稚T细胞不会被iDCs激活，而是进入无反应/缺失状态，并产生调节性T细胞以实现免疫耐受。免疫反应和耐受的诱导由iDCs严格调控，iDCs作为宿主免疫反应稳态的传感器。尽管已经鉴定出一些肿瘤抗原，但肿瘤免疫并未成功激发。尽管存在一些抑制有效肿瘤免疫的关键障碍，但肿瘤细胞能够利用iDCs的功能促进肿瘤进展，这是由肿瘤衍生的可溶性因子（如血管内皮生长因子（VEGF））诱导并在微环境中进行功能调节的。iDCs仍然是激发肿瘤免疫的关键靶点。在本综述中，将讨论肿瘤相关iDCs的功能作用以及在癌症患者的有效肿瘤免疫中靶向iDCs的策略。
