Endogenous and exogenous lipids, peptides, and proteins have been shown to bind and activate FPR2/ALX to produce inflammatory and anti-inflammatory effects (Takano et al. 1997; Cooray et al. 2013). Both the LXs and Rvs families, including LXA4, AT-LXA4 (15-epi-LXA4), RvD1, AT-RvD1 (17-epi-RvD1), and Annexin A1 (ANXA1) activate receptors with high potency. On the other hand, endogenous antagonists, including serum amyloid A (SAA) and cathelicidin (LL-37) have been identified (Bozinovski et al. 2012; Wan et al. 2011).