Additionally, B. breve has been reported to modulate the expression of TLRs, normalizing TLR4 expression, enhancing TLR2 expression, and reducing the expression of pro-inflammatory cytokines, including IL-1 beta, IL-6, and tumor necrosis factor alpha in an animal model of necrotizing enterocolitis (NEC) (Wong et al., 2019). Here, TLR4 is linked to necrotizing enterocolitis.