Prolow-density lipoprotein receptor-related protein 1 (LRP1)

Prolow-density lipoprotein receptor-related protein 1, commonly referred to as LRP1, is a massive, multifunctional transmembrane receptor that serves as a central hub for both endocytosis and cell signaling. Synthesized as a 600 kDa precursor, it is proteolytically processed into non-covalently linked 515 kDa and 85 kDa subunits that reside primarily on the plasma membrane of various tissues, including the liver, brain, and vascular endothelium. LRP1 is capable of binding over 40 diverse ligands—including apolipoprotein E (ApoE), alpha-2-macroglobulin, and amyloid-beta (Aβ)—facilitating their internalization and subsequent lysosomal degradation or transcytosis across cellular barriers. In clinical research, LRP1 is a major target for Alzheimer's disease due to its critical role in clearing Aβ from the brain; it is also exploited as a shuttle for delivering drugs across the blood-brain barrier via specialized peptides like Angiopep-2. Despite its therapeutic potential, the receptor's broad involvement in vital processes like lipid homeostasis, vascular integrity, and embryonic development necessitates highly specific targeting to avoid significant safety risks and systemic side effects.

Other names

Low-density lipoprotein receptor-related protein 1Alpha-2-macroglobulin receptor (A2MR)Apolipoprotein E receptor (APOER)Cluster of differentiation 91 (CD91)Type V TGF-beta receptor (TGFBR5)Insulin-like growth factor-binding protein 3 receptor (IGFBP3R)LRP-1

Drugs targeting LRP1 typically work by enhancing receptor-mediated endocytosis or transcytosis to facilitate the clearance of toxic proteins like amyloid-beta, or by utilizing the receptor's transport capacity to deliver therapeutic cargo across the blood-brain barrier. Additionally, some modulators upregulate the expression of the receptor at the cell surface or activate downstream intracellular signaling pathways such as MAPK and Akt to influence cell survival and metabolism.