PF4 and infection: Our results showed that topical LTB4 decreased lesion size and bacterial clearance in macrophage-depleted mice (Fig 5G and 5H), restored production of the chemokines, CCL2 and CXCL4, but not CXCL2 (S7A–S7C Fig), VEGF, IL-33, and IL-1β (S7D–S7F Fig) and neutrophil migration to the site of infection (S7G Fig) in DT-treated MMDTR mice.