Human ApoE has been used to study the role of apoE in the activity of LNP (lipid nanoparticles) in order to determine if ApoE has a role to play in the delivery of siRNA to hepatocytes.
Significant quantities of ApoE are produced in liver and brain and to some extent in almost every organ. ApoE is an important constituent of all plasma lipoproteins. It′s interaction with specific ApoE receptor enables uptake of chylomicron remnants by liver cells, which is an essential step during normal lipid metabolism. ApoE exists in three major isoforms; E2, E3, and E4, which differ from one another by a single amino-acid substitution. E3 is the most common isoform and is present in 40-90% of the population. Recombinant human ApoE3 is a 34.0 kDa protein containing 299 amino acid residues. The recombinant ApoE3 was manufactured using animal origin free technology.
ApoE belongs to a group of proteins that bind reversibly with lipoprotein and play an important role in lipid metabolism. In addition to facilitating solublization of lipids, these proteins help to maintain the structural integrity of lipoproteins, serve as ligands for lipoprotein receptors, and regulate the activity of enzymes involved in lipid metabolism. Apart from participating in the metabolism of plasma lipoproteins, apo-E also interacts with several proteoglycans, such as heparin. The interaction of lipoproteins with proteoglycans in the walls of arteries has been associated with cholesterol deposition linked to atherosclerosis. It is found to be a constituent of several lipoproteins and serves as a ligand for the LDL (low density lipoprotein) receptor, thereby regulating cholesterol and triglyceride homeostasis.
