CXCR2 and clostridium difficile infection: To directly test the role of CXCR2 in regulating neutrophil trafficking in response to CDI, we treated wildtype mice with a selective CXCR2 antagonist (SB225002 1 mg/kg i.p.)or control (PBS) for 2 days prior to CDI (Figure 1A) (White et al., 1998; Bento et al., 2008; Zhu et al., 2020).