Figure 5.

Neutralizing abilities of antibodies induced in immunized mice against C. perfringens natural α-toxin. C. perfringens natural α-toxin was treated with the serum IgG and mucosal sIgA antibodies obtained from the immunized mice in each group, followed by a challenge to the mice to evaluate the neutralizing abilities of the antibodies. A high survival rate was registered among the mice challenged with the α-toxin treated with IgG (a) or sIgA antibodies (b) induced by pPG-α/L. casei 393, whereas mice challenged with the α-toxin treated with antibodies obtained from mice immunized with pPG/L. casei 393 and PBS all died.