Microarray analysis of CD9high and CD9low progenitors isolated from omental adipose tissue of morbid obese individuals

Obesity-induced white adipose tissue (WAT) fibrosis is believed to accelerate WAT dysfunction. Two progenitor populations could be distinguished in omental white adipose tissue (oWAT) of morbidly obese individuals based on CD9 expression. In addition, the frequency of CD9high progenitors in oWAT correlates with oWAT fibrosis level, insulin-resistance severity and type 2 diabetes. To further gain insight into the functional differences between the CD9high and CD9low progenitor subsets, we performed transcriptomic profiling of FACS-sorted progenitor populations isolated from oWAT of obese individuals. As CD9low progenitors were markedly decreased in glucose-intolerant or diabetic individuals, we investigated seven women with morbid obesity but without diabetes or glucose intolerance, according to the ADA definition. Omental adipose tissue from 7 obese women with mean BMI of 42.9±1.7kg/m2 and mean age of 40.7±3.3 year-old was digested with collagenase. CD9high and CD9low progenitors from the stromal vascular fraction were FACS-sorted with CD45- CD31- CD34+ CD44+ PDGFRa+ CD9high and CD45- CD31- CD34+ CD44+ PDGFRa+ CD9low. Total RNA was amplified and labeled using Ovation Pico WTA System V2 (NuGEN) and Encore BiotinIL Module (NuGEN) kits according to the manufacturer's protocol.