CXCL1 and inflammatory bowel disease: Elevated CXCL1 expression in the gut of patients with inflammatory bowel disease may also depend on other factors such as interferon-stimulated gene product 15 (ISG15)/ubiquitin cross-reactive protein (UCRP) [158], IL-36α and IL-36γ [159], and the influence of gut microbiota [150,160].