CXCL3 and clostridium difficile infection: Notably, indomethacin pretreatment followed by CDI significantly upregulated several genes involved in innate immune cell activation and recruitment such as Il1b, Cxcl3, Csf3, and Cxcl1 and downregulated Cd4, Tlr5, and Tgfb2 (Fig. 3C and D).