S100A9 and inflammatory bowel disease: Multiple genes associated with myeloid cells and innate immunity, which we showed earlier were most highly expressed in the LPLs from infected Maffl/flCd4Cre mice (Fig. 5h), were over-expressed in human IBD, including IL1B, IL1A, CSF3, ACOD1, OSM, S100A8, S100A9 and CXCR2 (Fig. 7f).