TNF and inflammatory bowel disease: Many of these cytokines (or their receptors or ligands) have been associated with genetic susceptibility to IBD or have been suggested as drug targets for IBD, including TNF-α (ref 45), IL-6 (ref 46), IL-1RA47, CXCL10 (ref 48), and IL-12Rp40 (ref. 12) (Supplementary Table 24).