TNF and inflammatory bowel disease: Regarding the hypothesis of a possible modulation of ACE-2 expression by TNF-α, a recent study evidenced a synergistic effect of TNF-α and IFN-γ in increasing ACE-2 expression in human thyroid cells [54]; nevertheless, it is not possible to directly translate these data on epithelial lung cells in patients with IBD, who could have a higher TNF-α background signaling.