Oral vaccines, unlike injected, induce intestinal secretory immunoglobulin A (sIgA) mimicking our natural defense against gut pathogens. We previously observed sIgA responses after administering the colonisation factor CD0873 orally in enteric capsules to hamsters. Enteric-coated capsules are designed to resist dissolution in the stomach and disintegrate only at the higher pH of the small intestine.
View Article and Find Full Text PDFVibrio cholerae is the causative agent of the acute diarrheal disease of cholera. Innate immune responses to V. cholerae are not a major cause of cholera pathology, which is characterized by severe, watery diarrhea induced by the action of cholera toxin.
View Article and Find Full Text PDFBackground: Vibrio cholerae excreted by cholera patients is "hyperinfectious" (HI), which can be modeled by passage through infant mice. Immunization of adult female mice with V. cholerae outer-membrane vesicles (OMVs) passively protects suckling mice from challenge.
View Article and Find Full Text PDFBiofilms are a preferred mode of survival for many microorganisms including Vibrio cholerae, the causative agent of the severe secretory diarrhoeal disease cholera. The ability of the facultative human pathogen V. cholerae to form biofilms is a key factor for persistence in aquatic ecosystems and biofilms act as a source for new outbreaks.
View Article and Find Full Text PDFThe ability of Vibrio cholerae to persist in bodies of water will continue to confound our ability to eradicate cholera through improvements to infrastructure, and thus cholera vaccines are needed. We aim for an inexpensive vaccine that can provide long-lasting protection from all epidemic cholera infections, currently caused by O1 or O139 serogroups. Recent insights into correlates of protection, epidemiology and pathogenesis may help us design improved vaccines.
View Article and Find Full Text PDFVibrio cholerae is the causative agent of cholera, a severe diarrheal disease that remains endemic in many parts of the world and can cause outbreaks wherever sanitation and clean water systems break down. Prevention of disease could be achieved through improved sanitation and clean water provision supported by vaccination. V.
View Article and Find Full Text PDFOuter membrane vesicles (OMVs) offer a new approach for an effective cholera vaccine. We recently demonstrated that immunization of female mice with OMVs induces a long-lasting immune response and results in protection of their neonatal offspring from Vibrio cholerae intestinal colonization. This study investigates the induced protective immunity observed after immunization with OMVs in more detail.
View Article and Find Full Text PDFAt the International Centre for Diarrhoeal Disease Research, Bangladesh, one-half of the rice-water stool samples that were culture-positive for Vibrio cholerae did not contain motile V. cholerae by standard darkfield microscopy and were defined as darkfield-negative (DF(-)). We evaluated the host and microbial factors associated with DF status, as well as the impact of DF status on transmission.
View Article and Find Full Text PDFCitrobacter rodentium belongs to a family of extracellular enteric pathogens that include enterohaemorrhagic and enteropathogenic Escherichia coli, which colonises the gastrointestinal mucosa by the attaching and effacing (A/E) mechanism. We previously described the appearance of a 'hyper-infectious' state after passage of C. rodentium through the murine gastrointestinal tract.
View Article and Find Full Text PDFThe divergence of Salmonella enterica and Escherichia coli is estimated to have occurred approximately 140 million years ago. Despite this evolutionary distance, the genomes of these two species still share extensive synteny and homology. However, there are significant differences between the two species in terms of genes putatively acquired via various horizontal transfer events.
View Article and Find Full Text PDF