Recombinant Human GPR84 protein

GPR84 is a class A G protein-coupled receptor (GPCR) primarily expressed in immune cells, including macrophages, neutrophils, and microglia. It was initially identified as an orphan receptor but was later deorphanized upon discovering its activation by medium-chain free fatty acids (MCFAs) with 9–14 carbon chains, such as lauric acid (C12:0). GPR84 plays a role in pro-inflammatory responses, linking metabolic changes to immune regulation. It is upregulated during tissue injury, infection, or metabolic stress, suggesting involvement in inflammation, fibrosis, and metabolic disorders. Signaling through GPR84 activates Gαi/o proteins, leading to reduced cAMP levels and modulation of pathways like MAPK and NF-κB, which drive cytokine production and immune cell migration.

Recombinant GPR84 proteins are engineered to study its structure, ligand interactions, and signaling mechanisms. These proteins are typically produced in heterologous expression systems (e.g., HEK293. insect, or bacterial cells) and often include tags (e.g., His, FLAG) for purification and detection. Recombinant forms may feature mutations to stabilize active/inactive conformations, enabling structural studies (e.g., X-ray crystallography, cryo-EM) or high-throughput drug screening. They are critical tools for identifying synthetic agonists/antagonists, as GPR84 is a therapeutic target for inflammatory diseases (e.g., colitis, pulmonary fibrosis), cancer, and metabolic syndrome. Recent studies also explore its role in neurodegenerative diseases, where neuroinflammation mediated by GPR84 may influence progression. However, its dual pro- and anti-inflammatory roles under different conditions require further investigation using recombinant systems to dissect context-dependent signaling.