A foam cell model was developed by exposure of Chinese Hamster ovary cells to 20μg/ml β-VLDL. In this foam cell model hormone-sensitive lipase(HSL) activity was overexpressed using adenovirus complexed with the rat HSL gene.Nearly 300 folds increase of intracellular cholesteryl ester hydrolase activity was achieved in transfected cells compared with the control cells. When cells overexpressing HSL were incubated with β-VLDL,cholesteryl ester levels were only 25% of those seen in control cells. Thus, HSL strongly inhibits cholesteryl ester accumulation in this foam cell model.