Effects of kampo-hozais on the induction of oral tolerance to ovalbumin in mice.

We studied here the effect of 3 kinds of kampo-hozais (Shofu-san, Ji-zuso-ippo and Unsei-in) on the induction of oral tolerance to ovalbumin (OVA) in C3H/HeN mice by measuring serum levels of OVA-specific antibodies. Oral tolerance was induced by a single administration of OVA (2 or 20 mg, p.o.) 7 d before the immunization. Among these kampo-hozais, mice administered Ji-zuso-ippo for 7 d before feeding of 2 mg OVA had significantly lower levels of anti-OVA IgG and IgG1, and further, Ji-zuso-ippo tended to reduce anti-OVA Igs in 20 mg OVA-fed mice, whereas Ji-zuso-ippo did not alter anti-OVA Igs in non-OVA-fed mice. Unsei-in also slightly augmented the suppression of anti-OVA IgG and IgG1; however, this lowering action of Unsi-in should be due to its immunosuppressive effect. Shofu-san did not alter these anti-OVA Ig levels in serum. These results suggested that Ji-zuso-ippo could augment the induction of oral tolerance.