Intestinal immune response in mice after oral exposure to food-grade SiO2. (A) The protocol for testing the effects on intestinal immune response of daily exposure of C57BL/6J mice to the vehicle (water) or to the food-grade SiO2 (fg-SiO2; 1, 10, or 100mg/kg BW/d) through gavage. (B) Fecal lipocalin-2 (Lcn2) levels in mice orally exposed to food-grade SiO2 (fg-SiO2) (n=8 mice per group) or to the vehicle (n=10) for 60 d. (C–E) Amounts of γIFN-γ (C), IL-10 (D), and βTGF-β (E) secreted by mesenteric lymph node cells from mice orally exposed to fg-SiO2 (n=8 mice per group) or to the vehicle (n=10) for 60 d. The data are expressed as median with interquartile range and whiskers extending from minimum to maximum ± SEM. *p
