BACKGROUND Cholera toxin B subunit (CTB) was shown to be a potent adjuvant for protein immunogen, especially when inoculated through mucosal route. We aimed to optimize the expression approach for CTB and thereafter to determine the adjuvant effect on DNA vaccine. METHODS Wild type CTB coding gene was amplified and cloned into prokaryotic expression vector pET-30a, and the recombinant CTB was...

cholera toxin b subunit (ctxb) is a homopantameric, nontoxic subunit of cholera toxin that is responsible for its binding to the cell and has been known as a mucosal adjuvant for vaccines that could increase homoral and mocusal immunity response. in this work, the ctxb gene was fused to the stxb gene from shigella dysenteriae type i a vaccine antigen candidate against this pathogen, by a nonfur...

BACKGROUND Current influenza vaccines need to be annually reformulated to well match the predicated circulating strains. Thus, it is critical for developing a novel universal influenza vaccine that would be able to confer cross-protection against constantly emerging divergent influenza virus strains. Influenza virus A is a genus of the Orthomyxoviridae family of viruses. Influenza virus nucleop...

Vibrio cholerae produces cholera toxin (CT), an AB5 protein toxin that is primarily responsible for the profuse watery diarrhea of cholera. CT is secreted into the extracellular milieu, but the toxin attacks its Gsα target within the cytosol of a host cell. Thus, CT must cross a cellular membrane barrier in order to function. This event only occurs after the toxin travels by retrograde vesicula...

Many bacterial toxins bind to and gain entrance to target cells through specific interactions with membrane components. Using neutron reflectivity, we have characterized the structure of mixed DPPE:GM(1) lipid monolayers before and during the binding of cholera toxin (CTAB(5)) or its B-subunit (CTB(5)). Structural parameters such as the density and thickness of the lipid layer, extension of the...

Homing of leukocytes to various tissues is dependent on the interaction between homing receptors on leukocytes and their ligands, addressins, on endothelial cells. Mucosal immunization results in homing of antigen-specific lymphocytes back to the mucosa where they first encountered the antigen. However, it is unknown whether this homing of antigen-specific cells is mediated by an altered endoth...

The pathways involved in the emotional aspects of thirst, the arousal and affect associated with the generation of thirst and the motivation to obtain satiation, have been studied but remain poorly understood. Rats were therefore injected with the neurotropic virus pseudorabies in either the insular or cingulate cortex. After 2 days of infection, pseudorabies-positive neurons were identified wi...

A direct pathway from the retina to the dorsal raphe nucleus (DRN) has been demonstrated in both albino rats and Mongolian gerbils. Following intraocular injection of cholera toxin subunit B (CTB), a diffuse stream of CTB-positive, fine-caliber optic axons emerged from the optic tract at the level of the pretectum/anterior mesencephalon. In gerbils, CTB-positive axons descended ventromedially i...

Cells rapidly repair plasma membrane (PM) damage by a process requiring Ca(2+)-dependent lysosome exocytosis. Acid sphingomyelinase (ASM) released from lysosomes induces endocytosis of injured membrane through caveolae, membrane invaginations from lipid rafts. How B lymphocytes, lacking any known form of caveolin, repair membrane injury is unknown. Here we show that B lymphocytes repair PM woun...

The present study evaluates the influence of cholera toxin and its B-subunit on thermic responses to morphine in the rats. The holotoxin (1 microg/rat) and the B-subunit (5 microg) were administered ICV and three days later rats were challenged ICV with morphine and tested for changes of body temperature. Cholera toxin, but not its B-subunit, modified the time course of the hyperthermic respons...