Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh, UK.
Immunol Rev. 2024 Jul;324(1):78-94. doi: 10.1111/imr.13339. Epub 2024 May 8.
It is now widely understood that visceral adipose tissue (VAT) is a highly active and dynamic organ, with many functions beyond lipid accumulation and storage. In this review, we discuss the immunological role of this tissue, underpinned by the presence of fat-associated lymphoid clusters (FALCs). FALC's distinctive structure and stromal cell composition support a very different immune cell mix to that found in classical secondary lymphoid organs, which underlies their unique functions of filtration, surveillance, innate-like immune responses, and adaptive immunity within the serous cavities. FALCs are important B cell hubs providing B1 cell-mediated frontline protection against infection and supporting B2 cell-adaptative immune responses. Beyond these beneficial immune responses orchestrated by FALCs, immune cells within VAT play important homeostatic role. Dysregulation of immune cells during obesity and aging leads to chronic pathological "metabolic inflammation", which contributes to the development of cardiometabolic diseases. Here, we examine the emerging and complex functions of B cells in VAT homeostasis and the metabolic complications of obesity, highlighting the potential role that FALCs play and emphasize the areas where further research is needed.
现在人们普遍认为内脏脂肪组织（VAT）是一个高度活跃和动态的器官，具有许多超出脂质积累和储存的功能。在这篇综述中，我们讨论了这种组织的免疫学作用，其基础是存在脂肪相关淋巴簇（FALC）。FALC 的独特结构和基质细胞组成支持与经典次级淋巴器官中发现的免疫细胞混合物非常不同，这构成了它们在浆膜腔中过滤、监视、先天样免疫反应和适应性免疫的独特功能。FALC 是重要的 B 细胞中心，提供 B1 细胞介导的抗感染第一线保护，并支持 B2 细胞适应性免疫反应。除了 FALC 协调的这些有益免疫反应外，VAT 中的免疫细胞还发挥着重要的体内平衡作用。肥胖和衰老期间免疫细胞的失调导致慢性病理性“代谢炎症”，这有助于心血管代谢疾病的发展。在这里，我们研究了 B 细胞在 VAT 体内平衡和肥胖代谢并发症中的新兴和复杂功能，强调了 FALC 所起的作用，并强调了需要进一步研究的领域。
