Objective     To explore the effects of intestinal microbiota on food allergy through observing the reaction of germfree mice to ovalbumin (OVA) stimulation after transplantation with fecal microbiota to allergic and nonallergic reaction SPF mice.      Methods       The intestinal microbiota of the allergic and nonallergic reaction SPF mice that were successfully induced by OVA were respectively transplanted into the germfree mice to establish the allergic reaction group (FA group) and nonallergic reaction group (NR group)

with 10 mice in each group. At the 3rd week after transplantation

7 mice in each group were randomly selected for OVA treatment and defined as FA-o group and NR-o group

and the rest 3 mice in each group were treated with sodium chloride physiological solution and defined as FA-c group and NR-c group. The colonization of the intestinal microbiota in the germ-free mice after transplantation was detected by denaturing gradient gel electrophoresis (DGGE)

and the differences of microbiota composition between FA group and NR group were compared. The clinical symptoms of the 2 groups after OVA stimulation were observed

and then the morphological changes of intestinal tissue were examined by HE staining.       Results          At the 3rd week after fecal microbiota transplantation

the DGGE bands were almost the same in the FA group and NR group as their own donor’s

but the DGGE bands of the FA group and NR group were significantly different. The 2 groups showed a clear separation in cluster analysis and principal component analysis (PCA). The sequencing results also showed that Firmicutes was predominate in the NR group

whereas Proteobacteria was dominant bacteria in the FA group. After OVA stimulation

the FA-o group had more obvious clinical symptoms than the NR-o group. HE staining showed that the FA-o group had more serious pathological changes than the NR-o group

such as inflammatory cell infiltration

focal necrosis and shedding of the epithelial cells in the intestinal villi.      Conclusion        The intestinal microbiota can affect the sensitivity to OVA in the transplanted mice

and the sensitivity to food allergy can be transmitted via the intestinal microbiota.