Finally, the combined administration of DPSCs and sulfasalazine significantly downregulated MyD88, NF-κB and TLR4 gene expression.<h4>Conclusions</h4>Cotreatment with DPSCs and sulfasalazine had synergistic effects on ulcerative colitis, and these effects were relieved. This evidence concerns the gene MYD88 and ulcerative colitis.