The FCM was performed as previously reported (10). Peritoneal exudates and cultured PMNs and MΦs were used for determining indicated antigens, including CD11b (clone M1/70, catalog no. 101206, BioLegend, San Diego, CA), F4/80 (clone BM8, catalog nos. 123110 and 123116, BioLegend), Ly6G (clone 1A8, catalog no. 127618, BioLegend), annexin V (catalog no. 640930, BioLegend), and mFgl2 (clone 6D9). The cellular fluorescence was assessed using FACSCanto II (BD), and data were analyzed with FlowJo v10 (Tree Star Inc., Ashland, OR). In Treg experiments, spleen CD4+CD25+ Tregs were isolated by fluorescence-activated cell sorting (FACS) and then treated with or without RvDp5 (10 nM) for 24 hours.