TLR4 and inflammatory bowel disease: In IBD, the expression levels of TLR4 are also upregulated, and TLR4 signaling has been shown to affect the intestinal microbiota via alterations in gastrointestinal motility that drives clearance of pathogens and maintenance of commensal populations, differentiation of goblet cells, and expression of antimicrobial peptides [1,122,123].