# Adipose-Tissue Macrophage Diversity and Functions

## TL;DR

This review explores the different types of macrophages in fat tissue and their roles in metabolism and obesity.

## Contribution

The paper highlights the newly identified lipid-associated macrophages and their role in obesity.

## Key findings

- Macrophage subsets in white adipose tissue have distinct markers and functions.
- Lipid-associated macrophages are abundant in obesity and regulate local lipid levels.
- Macrophages interact with stromal cells and influence tissue homeostasis.

## Abstract

Macrophages are the predominant immune cell type found in adipose tissue (AT). They play a critical role in tissue homeostasis and participate in metabolic regulation. In white adipose tissue (WAT), studies show that multiple macrophage subsets co-exist in the very same microenvironment. Yet these cells express selective membrane markers, allowing for identifying several well-distinguished populations. In the present review we discuss the diversity and functions of white-adipose-tissue macrophages. We summarize current knowledge regarding the intratissue distribution of macrophage populations and their specific association with stromal cells and discuss the mechanisms governing adipose-tissue macrophage generation and survival. We emphasize the central role of adipose-tissue macrophages in handling local lipid levels. A particular focus is placed on the recently described population of lipid-associated macrophages (LAMs), particularly abundant in adipose tissue during obesity development.