There is currently much interest in how different dendritic cell and macrophage populations contribute to T cell–mediated immunity. Although conventional dendritic cell subsets have received much attention for their role in T cell priming, there is emerging evidence for a role for monocyte-derived APC (MoAPC) in tissue-resident memory T cell (Trm) formation. Cells of the monocyte/macrophage lineage play a key role in providing chemokines and cytokines for the localization, differentiation, and survival of Trm and Trm precursors. In addition, inflammatory MoAPC are the key providers of TNF superfamily costimulatory signals, a signal we refer to as signal 4 for T cell activation. Recent evidence suggests that signal 4 from MoAPC occurs postpriming and substantially increases Trm formation. Key questions remain, such as the Ag dependence of signal 4 and the specific mechanisms by which MoAPC–Trm interactions affect the long-term maintenance of Trm.

中文翻译：

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组织驻留记忆 T 细胞形成中的单核细胞衍生细胞

目前，人们对不同的树突状细胞和巨噬细胞群体如何促进 T 细胞介导的免疫非常感兴趣。尽管传统的树突状细胞亚群因其在 T 细胞启动中的作用而受到很多关注，但有新的证据表明单核细胞衍生的 APC (MoAPC) 在组织驻留记忆 T 细胞 (Trm) 形成中的作用。单核细胞/巨噬细胞谱系的细胞在为 Trm 和 Trm 前体的定位、分化和存活提供趋化因子和细胞因子方面发挥着关键作用。此外，炎症性 MoAPC 是 TNF 超家族共刺激信号的关键提供者，我们将这种信号称为 T 细胞激活的信号 4。最近的证据表明，来自 MoAPC 的信号 4 发生在启动后并显着增加 Trm 的形成。关键问题仍然存在，