TLR4 and food allergy: Fecal calprotectin was positively correlated with S100A8/A9 in plasma, as was reported by Roseth [44], and with TLR4, TNF, and NF- kappa B. It is not difficult to speculate that elevated S100A8/A9 regulates the balance of Th1/ Th1 cells through the TLR4 pathway and amplifies the cascade of allergic factors and inflammatory factors in food allergy.