Perivascular niches are specialized microenvironments where stromal and immune cells interact with vasculature to monitor tissue status. Adventitial perivascular niches surround larger blood vessels and other boundary sites, supporting collections of immune cells, stromal cells, lymphatics, and neurons. Adventitial fibroblasts (AFs), a subtype of mesenchymal stromal cell, are the dominant constituents in adventitial spaces, regulating vascular integrity while organizing the accumulation and activation of a variety of interacting immune cells. In contrast, pericytes are stromal mural cells that support microvascular capillaries and surround organ-specific parenchymal cells. Here, we outline the unique immune and non-immune composition of perivascular tissue immune niches, with an emphasis on the heterogeneity and immunoregulatory functions of AFs and pericytes across diverse organs. We will discuss how perivascular stromal cells contribute to the regulation of innate and adaptive immune responses and integrate immunological signals to impact tissue health and disease.

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血管周围基质细胞：组织免疫生态位的负责人

血管周围的生态位是专门的微环境，基质和免疫细胞与脉管系统相互作用以监测组织状态。外膜血管周围壁龛围绕较大的血管和其他边界部位，支持免疫细胞、基质细胞、淋巴管和神经元的集合。外膜成纤维细胞 (AFs) 是间充质基质细胞的一种亚型，是外膜空间的主要成分，调节血管完整性，同时组织各种相互作用的免疫细胞的积累和激活。相反，周细胞是基质壁细胞，支持微血管毛细血管并围绕器官特异性实质细胞。在这里，我们概述了血管周围组织免疫生态位的独特免疫和非免疫组成，重点关注不同器官的 AF 和周细胞的异质性和免疫调节功能。我们将讨论血管周围基质细胞如何促进先天性和适应性免疫反应的调节，并整合免疫信号以影响组织健康和疾病。