Intracellular Toll-like receptors (TLRs) are key components of the innate immune system. Their expression in antigen-presenting cells (APCs), and in particular dendritic cells (DCs), makes them critical in the induction of the adaptive immune response. In DCs, they interact with the chaperone UNC93B1 that mediates their trafficking from the endoplasmic reticulum (ER) to endosomes where they are cleaved by proteases and activated. All these different steps are also shared by major histocompatibility complex class-II (MHCII) molecules. Here, we will discuss the tight relationship intracellular TLRs have with the antigen processing machinery in APCs for their trafficking and activation.

细胞内 Toll 样受体 (TLR) 是先天免疫系统的关键组成部分。它们在抗原呈递细胞 (APC)，特别是树突状细胞 (DC) 中的表达，使得它们对于诱导适应性免疫反应至关重要。在 DC 中，它们与伴侣 UNC93B1 相互作用，介导它们从内质网 (ER) 运输到内体，在那里它们被蛋白酶切割并激活。主要组织相容性复合体 II 类 (MHCII) 分子也共享所有这些不同的步骤。在这里，我们将讨论细胞内 TLR 与 APC 中抗原加工机制在运输和激活方面的紧密关系。