TNF and inflammatory bowel disease: The relative expression of pro-inflammatory cytokines (IL-6, TNF-α) and anti-inflammatory cytokine (IL-10) via RT-PCR indicated that pro-inflammatory cytokines were increased in colorectal tissues of the IBD group, but significantly decreased in the hucMSC-Ex group, while the IL-10 level was higher in the hucMSC-Ex group than in the IBD group (Fig. 2G).