Preadipocytes are isolated from omental, mesenteric, or perirenal adipose tissue and are tested for their ability to differentiate in culture to mature adipocytes. Preadipocytes are available cryopreserved or plated and mature adipocytes are available in a variety of plated formats. The greater omentum is the largest peritoneal fold within the abdomen and has an immunologic function. The omentum aids in isolating peritoneal infection and absorbing contaminants through the mesothelial stomata. Adipokines and fatty acids from this depot have direct access to the liver through the portal circulation which may lead to hepatic dysfunction.