Among professional antigen-presenting cells, dendritic cells (DCs) orchestrate innate and adaptive immunity and play a pivotal role in anti-tumor immunity. DCs are a heterogeneous population with varying functions in the tumor microenvironment (TME). Tumor-associated DCs differentiate developmentally and functionally into three main subsets: conventional DCs (cDCs), plasmacytoid DCs (pDCs), and monocyte-derived DCs (MoDCs). There are two major subsets of cDCs in TME, cDC1 and cDC2. cDC1 is critical for cross-presenting tumor antigens to activate cytotoxic CD8+T cells and is also required for priming earlier CD4+T cells in certain solid tumors. cDC2 is vital for priming anti-tumor CD4+T cells in multiple tumor models. pDC is a unique subset of DCs and produces type I IFN through TLR7 and TLR9. Studies have shown that pDCs are related to immunosuppression in the TME through the secretion of immunosuppressive cytokines and by promoting regulatory T cells. MoDCs differentiate separately from monocytes in response to inflammatory cues and infection. Also, MoDCs can cross-prime CD8+T cells. In this review, we summarize the subsets and functions of DCs. We also discuss the role of different DC subsets in shaping T cell immunity in TME and targeting DCs for potential immunotherapeutic benefits against cancer.
在专职抗原呈递细胞中，树突状细胞（DCs）协调先天性与适应性免疫，并在抗肿瘤免疫中发挥关键作用。DCs在肿瘤微环境中具有功能异质性，主要分化为三个功能亚群：经典树突状细胞（cDCs）、浆细胞样树突状细胞（pDCs）和单核细胞来源树突状细胞（MoDCs）。其中cDCs在肿瘤微环境中可进一步分为cDC1与cDC2两个主要亚群：cDC1通过交叉呈递肿瘤抗原激活细胞毒性CD8⁺ T细胞，在某些实体瘤中还对CD4⁺ T细胞的早期启动具有关键作用；cDC2则在多种肿瘤模型中对抗肿瘤CD4⁺ T细胞的启动至关重要。pDCs作为独特亚群，能通过TLR7和TLR9通路产生I型干扰素，研究表明其可通过分泌免疫抑制性细胞因子及促进调节性T细胞在肿瘤微环境中发挥免疫抑制作用。MoDCs由单核细胞在炎症信号与感染刺激下分化形成，同样具备交叉呈递抗原激活CD8⁺ T细胞的能力。本文系统综述了DCs各亚群的特征与功能，探讨了不同DC亚群在肿瘤微环境中对T细胞免疫的调控作用，并展望了靶向DCs在癌症免疫治疗中的应用前景。
肿瘤(癌症)患者之家