Catalyzes the deacylation of triacylglyceryl and cholesteryl ester core lipids of endocytosed low density lipoproteins to generate free fatty acids and cholesterol. a sterol ester + H2O = a fatty acid + a sterol + H(+) cholesteryl (9Z-octadecenoate) + H2O = (9Z)-octadecenoate + cholesterol + H(+) Optimum pH is 4.5-5 (PubMed:8112342). Optimum pH is 4.4 with either cholesterol oleate or trioleoylglycerol as substrate (PubMed:7204383). Monomer. Most abundantly expressed in brain, lung, kidney and mammary gland, a moderate expression seen in placenta and expressed at low levels in the liver and heart. Glycosylation is not essential for catalytic activity. The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Belongs to the AB hydrolase superfamily. Lipase family.