The effects of oral administration of silica nanoparticles on immunologic response to the food antigen (P3220)

Abstract With the recent development of nanotechnology,nanomaterial (NM) with particle size below 100 nm have been developed and applied in various kinds of fields. For example, amorphous silica nanoparticles (nSP) have been already used in various foods as anticaking agents. Under this circumstance, there is increasing the importance of ensuring the safety of NM in foods. We previously revealed that nSP can penetrate the intestinal barrier, however,did not induce significant general toxicity. On the other hand, when we are exposed nSP, many food antigens are also exposed simultaneously.Thus, to ensure the safety of nSP, it is important to evaluate the effects of the oral exposure to nSP on immune response to food antigen. Here, we evaluated the effects of oral administration of nSP with a diameter of 30 nm on immunologic response to the food antigen. C3H/HeJ mice were orally administrated OVA or OVA plus nSP on days 0, 7, 14 and 21. Seven days after last administration, we measured OVA-specific antibody levels. Significant induction of OVA-specific IgG levels wasnot observed in OVA group compared with control. On the other hand, the mice administrated OVA plus nSP had significantly increased OVA-specific IgG levels compared with control groups. These results suggested that oral administration of nSP induced the abrogation of immune tolerance to food antigen. Currently, we are trying to evaluate the relationship between nSP and induction of food allergy.