AUTHOR=Strand Kristina , Stiglund Natalie , Haugstøyl Martha Eimstad , Kamyab Zahra , Langhelle Victoria , Lawrence-Archer Laurence , Busch Christian , Cornillet Martin , Hjellestad Iren Drange , Nielsen Hans Jørgen , Njølstad Pål Rasmus , Mellgren Gunnar , Björkström Niklas K. , Fernø Johan TITLE=Subtype-Specific Surface Proteins on Adipose Tissue Macrophages and Their Association to Obesity-Induced Insulin Resistance JOURNAL=Frontiers in Endocrinology VOLUME=13 YEAR=2022 URL=https://www.frontiersin.org/journals/endocrinology/articles/10.3389/fendo.2022.856530 DOI=10.3389/fendo.2022.856530 ISSN=1664-2392 ABSTRACT=

A chronic low-grade inflammation, originating in the adipose tissue, is considered a driver of obesity-associated insulin resistance. Macrophage composition in white adipose tissue is believed to contribute to the pathogenesis of metabolic diseases, but a detailed characterization of pro- and anti-inflammatory adipose tissue macrophages (ATMs) in human obesity and how they are distributed in visceral- and subcutaneous adipose depots is lacking. In this study, we performed a surface proteome screening of pro- and anti-inflammatory ATMs in both subcutaneous- (SAT) and visceral adipose tissue (VAT) and evaluated their relationship with systemic insulin resistance. From the proteomics screen we found novel surface proteins specific to M1-like- and M2-like macrophages, and we identified depot-specific immunophenotypes in SAT and VAT. Furthermore, we found that insulin resistance, assessed by HOMA-IR, was positively associated with a relative increase in pro-inflammatory M1-like macrophages in both SAT and VAT.