Oral Immunization of Dogs with Purified Cholera Toxin, Crude Cholera Toxin, or B Subunit: Evidence for Synergistic Protection by Antitoxic and Antibacterial Mechanisms

Oral immunization of dogs with purified cholera toxin, crude cholera toxin, or B subunit: evidence for synergistic protection by antitoxic and antibacterial mechanisms.

The immunogenicity and safety of purified cholera toxin (CT), its B subunit, and a crude culture filtrate of toxigenic Vibrio cholerae (CrT) were compared in dogs immunized orally and challenged with virulent V. cholerae. CT and CrT caused marked protection in two- or three-dose regimens. Protection due to CT occurred only with doses that caused transient, sometimes severe, diarrhea in most dog...

Fusion of Cholera toxin B subunit (ctxB) with Shigella dysenteriae type I toxin B subunit (stxB), Cloning and Expression that in E. coli

Background and Objective: Shiga toxin (STx) is the main virulence factor in Shigella Dysenteriae type I and is composed of an enzymatic subunit STxA monomer and a receptor-binding STxB homopentamer. Shigella toxin B subunit (STxB) is a non-toxic homopentameric protein responsible for toxin binding and internalization into target cells by interacting with glycolipid (Gb3). Cholera toxi...

Immunization with Cholera Toxin B Subunit Induces High-Level Protection in the Suckling Mouse Model of Cholera

Cholera toxin (CT) is the primary virulence factor responsible for severe cholera. Vibrio cholerae strains unable to produce CT show severe attenuation of virulence in animals and humans. The pentameric B subunit of CT (CTB) contains the immunodominant epitopes recognized by antibodies that neutralize CT. Although CTB is a potent immunogen and a promising protective vaccine antigen in animal mo...

Mucosal immunization with a genetically engineered pertussis toxin S1 fragment-cholera toxin subunit B chimeric protein.

A chimeric protein consisting of a divalent pertussis toxin (PT) S1 fragment linked to the cholera toxin (Ctx) A(2)B fragment was constructed. The chimera induced a mucosal immunoglobulin A (IgA) and a serum IgG immune response to PT and CtxB in BALB/c mice following intranasal immunization. The immune sera neutralized PT in vitro. In the mouse model of Bordetella pertussis respiratory infectio...

Cholera Toxin B-Subunit Prevents Activation