Mast cell-expressed orphan receptor CCRL2 binds chemerin and is required for optimal induction of IgE-mediated passive cutaneous anaphylaxis.
J Exp Med Sep 29,
2008
Author(s):
Brian A Zabel
Susumu Nakae
Luis Zúñiga
Ji-Yun Kim
Takao Ohyama
Carsten Alt
Junliang Pan
Hajime Suto
Dulce Soler
Samantha J Allen
Tracy M Handel
Chang Ho Song
Stephen J Galli
Eugene C Butcher
Abstract:
Mast cells contribute importantly to both protective and pathological IgE-dependent immune responses. We show that the mast cell-expressed orphan serpentine receptor mCCRL2 is not required for expression of IgE-mediated mast cell-dependent passive cutaneous anaphylaxis but can enhance the tissue swelling and leukocyte infiltrates associated with such reactions in mice. We further identify chemerin as a natural nonsignaling protein ligand for both human and mouse CCRL2. In contrast to other "silent" or professional chemokine interreceptors, chemerin binding does not trigger ligand internalization. Rather, CCRL2 is able to bind the chemoattractant and increase local concentrations of bioactive chemerin, thus providing a link between CCRL2 expression and inflammation via the cell-signaling chemerin receptor CMKLR1.