The proof of this theory seems to be the fact that plasma concentrations and tissue expression of the proinflammatory cytokines interleukin 1β (Il-1β) and interleukin 6 (Il-6), as well as tumor necrosis factor alpha (TNF-α) [7], are elevated in neonates with NEC [8, 9]. Here, IL1B is linked to necrotizing enterocolitis.