Plays a role in lipoprotein-mediated cholesterol uptake in hepatocytes. Binds cholesterol. Binds free fatty acids and their coenzyme A derivatives, bilirubin, and some other small molecules in the cytoplasm. May be involved in intracellular lipid transport. Monomer. Forms a beta-barrel structure that accommodates hydrophobic ligands in its interior. Deamidation and transpeptidation at the beta carboxyl of Asn-105 forms an isoaspartyl residue and Edman degradation appears as though blocked. This rearrangement gives rise to an extra negative charge carried by the acid form. Belongs to the calycin superfamily. Fatty-acid binding protein (FABP) family.