title: The safety of a mucosal vaccine using the C-terminal fragment of Clostridium perfringens enterotoxin.
abstract: The C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE) is a claudin-4 binder. Very recently, we found that nasal immunization of mice with C-CPE-fused antigen activated antigen-specific humoral and mucosal immune responses and that the deletion of the claudin-4-binding domain attenuated the immune responses. C-CPE-fusion strategy may be useful for mucosal vaccination. C-CPE is a fragment of enterotoxin, and the safety of C-CPE-fused protein is very important for its future application. In the present study, we investigated whether C-CPE-fused antigen induces immune responses without mucosal injury by using ovalbumin (OVA) as a model antigen. Immunohistochemical analysis showed that claudin-4 was expressed in epithelial cell sheets bordering the nasal cavity. Nasal immunization with C-CPE-fused OVA dose-dependently elevated the OVA-specific serum IgG titer, which was 1000-fold greater than the titer achieved by immunization with OVA or a mixture of OVA and C-CPE at 5 microg of OVA. Nasal immunization with C-CPE-fused OVA (5 microg of OVA) activated Th1 and Th2 responses. Histological analysis showed no mucosal injury in the nasal cavity or nasal passage. C-CPE-fused OVA exhibited mucosal vaccination without mucosal injury. These findings indicate thatclaudin-4-targeting using C-CPE can be a potent strategy for mucosal vaccination.
authors.affiliation: Laboratory of Bio-Functional Molecular Chemistry, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Suzuki
authors.forename: H
authors.initials: H
authors.lastname: Kakutani
authors.forename: M
authors.initials: M
authors.lastname: Kondoh
authors.forename: A
authors.initials: A
authors.lastname: Watari
authors.forename: K
authors.initials: K
authors.lastname: Yagi
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D062506:Claudin-4; D003015:Clostridium Infections / Q000276:immunology / Q000517:prevention & control; D003016:Clostridium perfringens / Q000276:immunology; D004306:Dose-Response Relationship, Immunologic; D004768:Enterotoxins / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*; D005260:Female; D018928:Immunity, Mucosal / Q000276:immunology*; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000235:genetics; D007150:Immunohistochemistry; D008565:Membrane Proteins / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D010047:Ovalbumin / Q000737:chemistry; D010446:Peptide Fragments / Q000009:adverse effects / Q000276:immunology; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology; D022223:Vaccines, Subunit / Q000008:administration & dosage / Q000009:adverse effects* / Q000276:immunology*
chemical_list: D062506:Claudin-4; C568158:Cldn4 protein, mouse; D004768:Enterotoxins; D007074:Immunoglobulin G; D008565:Membrane Proteins; D010446:Peptide Fragments; D022223:Vaccines, Subunit; C035598:enterotoxin, Clostridium; D010047:Ovalbumin