OBJECTIVETo illustrate the effects of the site and method of liposuction on differentiation of human preadipocytes.

METHODSForty-two fatty samples were obtained with liposuction, which were then divided into four groups according to operation sites (abdomen, hip or extremity) and the methods (conventional negative-pressure or syringe method). Each sample was treated with collagenase I to release preadipocytes for in vitro culture. Affected by the differentiation-induced agents for 9 days or 28 days, the cultured adipocytes were stained with Nile red and observed under a fluorescent microscope. The differentiation rates were examined with flow cytometric analysis and the quantity of intracytoplasmic lipids was determined with oil red O staining. The results were analyzed with independent samples t-test (Mann-Whitney) using SPSS 10.0.

RESULTSThere was no statistical difference in differentiation at the 9th day or 28th day among the preadipocytes obtained from the abdomen, hip or extremity with the negative-pressure method. The preadipocytes from the abdomen differentiated more at the 28th day than the 9th day (P < 0.05), which was not observed in the hip or the extremity. The preadipocytes obtained from the abdomen with the negative-pressure method differentiated more than those with the syringe method (P < 0.05).

CONCLUSIONNo essential difference was found in preadipocyte differentiation among the liposuction sites, while the abdomen might have some superiority. The negative-pressure method of liposuction is the first option in future research of tissue engineering. The flow cytometric analysis is a convenient way to study preadipocyte differentiation.