ALXFPR2

ALXFPR2 is a G protein-coupled receptor of the formyl peptide receptor family. In humans it is encoded by the FPR2 gene and is also known as ALX/FPR2 or simply FPR2. The receptor binds a diverse set of ligands, including bacterial N-formyl peptides such as fMLF, lipid mediators like lipoxin A4, and host-derived anti-inflammatory peptides such as Annexin A1-derived peptides. Ligand binding activates heterotrimeric Gi/o proteins, leading to inhibition of adenylyl cyclase, intracellular calcium mobilization, activation of MAP kinases, and cytoskeletal rearrangements that drive chemotaxis and other effector functions in neutrophils, monocytes, and other cell types.

Expression of ALXFPR2 is observed on neutrophils, monocytes, dendritic cells, and various non-immune cells including airway epithelial cells and endothelial cells. It is involved in both recruitment of leukocytes to sites of infection and in the resolution of inflammation when engaged by anti-inflammatory ligands such as lipoxin A4 and Annexin A1-derived peptides.

Physiology and pathology: The receptor contributes to host defense against pathogens and to tissue repair, but dysregulation can contribute to chronic inflammatory diseases, neuroinflammation, and asthma. Its dual pro- and anti-inflammatory actions depend on tissue context and ligand repertoire. Because of its role in resolving inflammation, ALXFPR2 has attracted interest as a potential therapeutic target; agonists that promote resolution and antagonists that limit detrimental signaling are areas of active research.