Mouse Histamine H4 Receptor (HRH4) Protein

Background

HRH4 is a G protein-coupled receptor expressed predominantly in immune cells, such as mast cells, eosinophils, basophils, and T cells, where it regulates inflammatory and immune responses. HRH4 couples to Gi/o proteins, reducing cAMP levels and modulating calcium signaling, which influences chemotaxis, cytokine release, and immune cell activation. HRH4 plays a critical role in allergic inflammation, autoimmune diseases, and chronic inflammatory conditions, including asthma, dermatitis, and rheumatoid arthritis. Its activation enhances histamine-mediated recruitment of immune cells to inflammatory sites, amplifying the immune response. In addition to its role in peripheral tissues, HRH4 is expressed in the central nervous system, where it may modulate neuroinflammation and immune cell interactions. HRH4 antagonists are being investigated as potential therapeutics for inflammatory diseases, allergic disorders, and immune-mediated pathologies. Given its role in histamine-driven immune responses, HRH4 represents a promising target for modulating inflammation and improving outcomes in allergic and chronic inflammatory conditions.