Chylomicron micron remnants containing apolipoprotein E associate with the surfaces of cells in a process that probably involves several steps and that requires the presence (but not the catalytic activity) of heparan sulfate proteoglycan (HSPG)-associated hepatic lipase (HL). This process ultimately results in binding of the remnant to cell-surface LDL receptors (LDLR) (Ji et al. 1994). The molecular details of LDLR binding, and of the following steps of remnant endocytosis, are inferred from those of the coorresponding step of LDLR-mediated low-density lipoprotein (LDL) endocytosis. In the body, this process occurs in the liver.