Defect of oral tolerance in NC/Nga mice

The NC/Nga mouse is a model animal for human atopic dermatitis. In this study, we investigated oral tolerance induction in NC/Nga mice. In BALB/c mice, oral administration of ovalbumin (OVA) resulted in suppression of both OVA-specific T and B cell responses induced by OVA immunization. In NC/Nga mice, OVA-induced antigen (Ag) -specific T and B cell responses were significantly less than those in BALB/c mice. Furthermore, oral administration of OVA did not suppress OVA-specific immunoresponses in NC/Nga mice. We further examined antibody (Ab) response against food Ag by feeding mice an experimental diet that contained OVA or casein as a protein source. The level of serum OVA or casein-specific IgG was significantly higher in NC/Nga mice than in BALB/c mice. These results indicate that NC/Nga mice have a defect in the induction of oral tolerance. NC/Nga mice can therefore be used as a model for investigating the mechanism of oral tolerance.