PTGS2 and infection: Previous work revealed that COX-2-mediated inflammation in the bladders of Sensitized mice during the first 24 hr of challenge infection overcame colonization resistance to allow severe acute and chronic rUTI, in part by promoting excessive neutrophil transmigration across the epithelium that caused severe bladder inflammation and mucosal wounding (Hannan et al., 2014; O'Brien et al., 2016).