A combined blockade of TL1A and IL-12/IL-23 signaling is hypothesized to limit their synergy, consequently downregulating IFN-γ and IL-17 production by CD4+ T cells and attenuating Th1/Th17 activation that underlies IBD (Takedatsu et al., 2008). Here, TNFSF15 is linked to inflammatory bowel disease.