In addition to chemerin, RvE1 was identified as a second endogenous agonist through a screening program against the GPCR panel (Arita et al. 2007). ERV1 (chemokine like receptor 1, also known as CMKLR1) is a receptor for RvE1, which has been shown to bind more strongly than chemerin (a peptide ligand) (Arita et al. 2005; Wittamer et al. 2004). ERV1 overexpressing mice showed a large increase in phagocytosis upon decreased neutrophil inhibition and decreased neutrophil infiltration (Herrera et al. 2015). Also, RvE2 is a partial agonist compared to RvE1 in CHO-chemerin1 β-arrestin recruitment (Isobe et al. 2012a). However, since there is no additional information on this ligand, further investigation of potential ligand-receptor pairs is required.