The application of an alanine-substituted mutant of the C-terminal fragment of Clostridium perfringens enterotoxin as a mucosal vaccine in mice

• Published in: Biomaterials 2012-01, Vol.33 (1), p.317-324
• Main Authors: Suzuki, Hidehiko, Kondoh, Masuo, Kakutani, Hideki, Yamane, Seiji, Uchida, Hiroshi, Hamakubo, Takao, Yagi, Kiyohito
• Format: Article
• Language: English
• Subjects: Advanced Basic Science; Alanine - chemistry; Alanine - genetics; Animals; Bacterial Vaccines - genetics; Bacterial Vaccines - immunology; Claudin; Claudin-4; Claudins - immunology; Claudins - metabolism; Clostridium Infections - immunology; Clostridium Infections - prevention & control; Clostridium perfringens; Clostridium perfringens - immunology; Clostridium perfringens enterotoxin; Dentistry; Enterotoxins - genetics; Enterotoxins - immunology; Enterotoxins - metabolism; Enzyme-Linked Immunosorbent Assay; Female; Mice; Mice, Inbred BALB C; Mucosal vaccine; Mucous Membrane - immunology; Mucous Membrane - metabolism; Mucous Membrane - microbiology; Ovalbumin - immunology; Targeting
• ISSN: 0142-9612; 1878-5905
• DOI: 10.1016/j.biomaterials.2011.09.048

Abstract Efficient delivery of antigen to mucosal immune tissues is an essential part of mucosal vaccination. Claudin-4 is expressed on the epithelial cells that cover the mucosal immune tissues. We previously found that claudin-4-targeting is a promising strategy for mucosal vaccination by using a claudin-4 binder, the C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE). Substitution of Asn and Ser at positions 309 and 313, respectively, with alanine increased the affinity of C-CPE for claudin-4. However, application of the C-CPE mutant as a mucosal vaccine has never been tried. Here, we investigated whether the C-CPE mutant could serve as a mucosal vaccine. We used ovalbumin (OVA) as a model antigen and fused the C-CPE mutant to it. The resultant fusion protein was bound to claudin-4. When mice were immunized with the C-CPE mutant-fused OVA, OVA-specific serum IgG and nasal IgA increased relative to levels in mice immunized with a C-CPE-fused antigen. Immunization with the C-CPE mutant-fused OVA activated Th1- and Th2-type responses and led to increased anti-tumor activity against OVA-expressing thymoma cells relative to that of mice immunized with the C-CPE-fused antigen. These findings suggest that the alanine-substituted C-CPE mutant shows promise as a claudin-targeted mucosal vaccine.