Construction and characterization of bivalent Shigella flexneri 2a vaccine strains SC608(pCFAI) and SC608(pCFAI/LTB) that express antigens from enterotoxigenic Escherichia coli.

Live Attenuated Shigella as a Diarrheal Vaccine And/or Mucosal Delivery Vector for Dna Vaccines

Several live attenuated Shigella vaccines of different serotypes have been shown to be safe, immunogenic, and in one case effective against challenge with virulent strains. The ability to invade epithelial cells remains critical for the success of these vaccine candidates. Live, orally administered Shigella vaccine derivatives are also being evaluated as multivalent mucosal vaccines able to del...

Immunogenic Evaluation of Bivalent Vaccine Candidate against Enterohemorrhagic and Enterotoxigenic Escherichia coli

Background: Caused by bacterial, viral, and parasitic pathogens, diarrhea is the second leading cause of death among children under five. Two strains of E. coli, namely Enterotoxigenic, ETEC and Enterohemorrhagic EHEC are the most important causes of this disease in developing countries. EHEC is a major causative agent of bloody diarrhea and hemorrhag...

Further Characterization of DaroA DvirG Shigella flexneri 2a Strain CVD 1203 as a Mucosal Shigella Vaccine and as a Live-Vector Vaccine for Delivering Antigens of Enterotoxigenic Escherichia coli

Engineered and construction of pDS132::∆virG as suicide vector for targeted gene deletion of virG from Shigella flexneri 2a in order to generation a live attenuated Shigella vaccine

Background & Objective: Shigella are Gram negative bacteria capable of inducing their entry into non-phagocytic cells via secretion of various effector proteins called invasion plasmid antigens (Ipas). The most important of them is VirG protein. Live attenuated Shigella vaccines have indicated promise in inducing protective immune responses in human clinical trials. In current situation, const...

Attenuated Shigella flexneri 2a vaccine strain CVD 1204 expressing colonization factor antigen I and mutant heat-labile enterotoxin of enterotoxigenic Escherichia coli.

A multivalent live oral vaccine against both Shigella spp. and enterotoxigenic Escherichia coli (ETEC) is being developed based on the hypothesis that protection can be achieved if attenuated shigellae express ETEC fimbrial colonization factors and genetically detoxified heat-labile toxin from a human ETEC isolate (LTh). Two detoxified derivatives of LTh, LThK63 and LThR72, were engineered by s...