Atypical Chemokine Receptor 4 Antibodies

Atypical chemokine receptor 4 (ACKR4), formerly known as CCRL1 or CCX-CKR, is a seven-transmembrane receptor that binds the endogenous chemokines CCL19, CCL21, and CCL25. It internalizes these ligands and directs them toward degradation without triggering the conventional G protein-dependent signaling that drives chemotaxis. ACKR4 cycles between the cell surface and endosomal compartments, and residues in its C-terminal tail regulate chemokine uptake and β-arrestin recruitment. In lymph nodes, ACKR4 is expressed by lymphatic endothelial cells lining the ceiling of the subcapsular sinus. By removing CCL19 and CCL21, it shapes chemokine gradients that guide CCR7-expressing dendritic cells from the sinus into the lymph node parenchyma. ACKR4 expression has also been reported in skin keratinocytes, thymic stromal cells, and subsets of intestinal fibroblasts. Mouse studies show that ACKR4-mediated scavenging in the skin helps regulate dendritic cell migration to draining lymph nodes. No ACKR4-selective drug has been reported to enter clinical trials or receive approval for therapeutic use. ACKR4 receptor function is regulated by phosphorylation of carboxyl-terminal serine338/threonine342 (pS338/pT342-ACKR4). This nomenclature refers to the human ACKR4 receptor. This phosphorylation motif is highly conserved across species and is identical in mice and humans. For more information on ACKR4 pharmacology please refer to the IUPHAR database. For further reading refer to:

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