Adipose tissue stromal cells from lean, obese, and formerly obese mice

Adipose tissue stromal cells contribute to the regulation of adipose tissue in lean and obese states. Myeloid cells such as adipose tissue macrophages (ATMs) and dendritic cells (ATDCs) undergo both quantitative and qualitative changes with obesity. Due to similarity in markers the identify of adipose tissue dendritic cells and macrophages has been elusive. We have refined prior protocols to unambiguously discern ATM and ATDC in mice. We used microarrays to compare the profiles of ATMs and ATDC from gonadal adipose tissue from lean, obese, and formerly obese mice. We also isolated preadipocytes (PA) from lean and obese mice for comparison. Male C57Bl/6 mice were fed normal diet (ND) or high fat diet (HFD) for 16 weeks. Weight loss (WL) mice were switched from the HFD to ND for 8 weeks. RNA was purified from FACS sorted cell populations (live cells only) obtained from gonadal/epididymal adipose tissue depots. ATMs were defined as CD11c+ (CD45+CD64+ CD11c+) or CD11c- (CD45+CD64+ CD11c-) ATMs. ATDC were defined as CD64- CD11c+. PA were defined as CD31- CD45- Sca1+ PDGFRA+. For ATM and ATDC analysis, 2 pools of cells from 4 ND mice were analyzed and 3 pools of 3-4 HFD mice were analyzed. For PA, 3 pools of 3-4 ND and HFD mice were analyzed. Due to the paucity of cells, CD11c+ ATM in ND mice were not purified.