Complement Factor 5a Receptor 1 (C5aR1)

C5aR1 is a G protein-coupled receptor that specifically binds the complement component C5a, an anaphylatoxin generated during activation of the complement system. It plays a key role in inflammatory responses, tissue regeneration, and bone physiology. Activation of C5aR1 leads to downstream signaling events including cytokine secretion, chemotaxis, and phagocytosis. It has been implicated in various diseases including cancer, inflammatory conditions, and cardiovascular disorders. Potent selective agonists/antagonists have been developed for research or therapeutic purposes targeting inflammatory diseases. Blockade of the C5a-C5aR1 axis has shown potential benefits but also mixed results depending on disease context.

Other names

CD88Complement component 5a receptor 1C5AR1

GPCR signaling via Gαi proteins and β-arrestin recruitment; ERK/MAPK pathway activation; Intracellular calcium mobilization