C5a receptor
Mammalian protein found in Homo sapiens
From Wikipedia, the free encyclopedia
The C5a receptor also known as complement component 5a receptor 1 (C5AR1) or CD88 (Cluster of Differentiation 88) is a G protein-coupled receptor for C5a. It functions as a complement receptor.[5] C5a receptor 1 modulates inflammatory responses, obesity, development and cancers.[6][7][8] From a signaling transduction perspective, C5a receptor 1 activation is implicated in β-arrestin2 recruitment via Rab5a,[9] coupling of Gαi proteins,[10] ERK1/2 phosphorylation,[11] calcium mobilization and Rho activation[12] leading to downstream functions, such as secretion of cytokines, chemotaxis, and phagocytosis.
Cells
The C5a receptor 1 is expressed on:[13][14]
- Granulocytes
- Macrophages
- Basophils
- Eosinophils
- Monocytes
- Neutrophils
- Dendritic cells
- Hepatoma-derived cell line HepG2
- Astrocytes
- Microglia
Agonist and antagonists
Clinical significance
C5a receptor 1 (C5AR1) has been implicated in the pathogenesis of several inflammatory and immune-mediated disorders through its role in neutrophil recruitment and activation.
In dermatological diseases, increased C5AR1 signaling has been associated with neutrophil-driven inflammation in hidradenitis suppurativa and chronic spontaneous urticaria. [21]
In renal disease, activation of the C5a–C5AR1 pathway has been implicated in lupus nephritis and C3 glomerulopathy. [22] [23]
Experimental studies have also implicated C5AR1 signaling in neuroinflammatory processes, including central nervous system manifestations of systemic lupus erythematosus and microglial activation in neurodegenerative disease models. [24]
C5AR1 has also been investigated in cancer biology, where it has been associated with the recruitment of immunosuppressive myeloid cells within the tumor microenvironment. Consequently, C5AR1 has been studied as a potential target for combination cancer immunotherapy. [25]
See also
- Complement component 5a for binding mechanism