It is not entirely clear how Bifidobacterium species protect the neonatal intestine against NEC, but recent reports show that B. infantis exerts an anti-inflammatory effect by decreasing TLR4 mRNA and increasing TOLLIP and SIGIRR mRNA levels in immature human intestinal xenografts and NEC intestinal epithelial cells [4]. The gene discussed is TLR4; the disease is necrotizing enterocolitis.