Perivascular Adipose Tissue Niches for Modulating Immune Cell Function

Perivascular adipose tissue is a unique fat depot surrounding most blood vessels with a significant role in vascular function. While adipocytes compose the vast majority of the perivascular adipose tissue by area, they only account for around 20% of the total cell number. Most of the cellular component belongs to resident immune cells, with macrophages and lymphoid cells representing ≈30% and 15% of total cells, respectively. Recently, new evidence has shown that aside from their well-known role in modulating the inflammatory tone, immune cells in perivascular adipose tissue can control adipogenesis, vessel integrity, and vascular contractility through complex cellular interactions. These interactions are spatially coordinated and influenced by the environmental state. Here, we review the mechanism by which immune cells regulate perivascular adipose tissue function with a special focus on the spatial organization of immune cells and their heterotypic interactions, supporting tissue function in health and disease.