Recombinant Bacteria Expressing Oligosaccharide Receptor Mimics For Prevention Of Enteric Infections
Funder
National Health and Medical Research Council
Funding Amount
$451,056.00
Summary
Gastrointestinal infectious diseases kill more than 3 million people each year. The principal microbial pathogens responsible for these infections are known to exploit oligosaccharides on the surface of host cells as receptors for ahesins or toxins. We have developed (and patented) a novel anti-infective strategy, based on mimicry of oligosaccharide receptors for toxins and adhesins produced by enteric pathogens on the surface of harmless carrier bacteria. Oral administration of such recombinant ....Gastrointestinal infectious diseases kill more than 3 million people each year. The principal microbial pathogens responsible for these infections are known to exploit oligosaccharides on the surface of host cells as receptors for ahesins or toxins. We have developed (and patented) a novel anti-infective strategy, based on mimicry of oligosaccharide receptors for toxins and adhesins produced by enteric pathogens on the surface of harmless carrier bacteria. Oral administration of such recombinant probiotics has the potential to prevent enteric infections by binding and neutralizing toxins in the gut lumen and by blocking adherence of the pathogen to intestinal epithelial cells. As a prototypic example, we have developed a bacterium capable of preventing the serious consequences of Shiga toxigenic Escherichia coli (STEC) infections; this agent binds Shiga toxin with very high efficiency and is 100% protective in animal models. The strategy has very broad applications, however, and receptors for virtually any pathogen can be mimicked by expression of appropriate glycosyl transferases in a suitable harmless host bacterium. This proposal involves extension of our existing work to develop therapeutic agents for other important life threatening diarrhoeal diseases including cholera, travellers' diarrhoea, dysentery, antibiotic-associated colitis, rotavirus, etc.Read moreRead less
Synthesis And Purification Of Flavivirus-specific Antiviral Factor Mrasal
Funder
National Health and Medical Research Council
Funding Amount
$140,000.00
Summary
In this proposal we suggest to develop an anti-flaviviral compound based on naturally occurring host factors associated with inborn flavivirus resistance observed in mice. We propose to synthesise and purify a mouse protein factor encoded by a gene (Mrasal), which we have previously mapped by mouse genetics and positional cloning to a narrow 300 kb chromosomal region on mouse chromosome 5 carrying flavivirus resistance locus (Flv). When this mouse gene was isolated, sub cloned into a mammalian e ....In this proposal we suggest to develop an anti-flaviviral compound based on naturally occurring host factors associated with inborn flavivirus resistance observed in mice. We propose to synthesise and purify a mouse protein factor encoded by a gene (Mrasal), which we have previously mapped by mouse genetics and positional cloning to a narrow 300 kb chromosomal region on mouse chromosome 5 carrying flavivirus resistance locus (Flv). When this mouse gene was isolated, sub cloned into a mammalian expression vector pcDNA3tag and transiently transfected and expressed in cos-7 and Vero cells, its product conferred antiviral effect to a flavivirus Murray Valley encephalitis (MVE), but not to a non-flavivirus encephalomyocarditis virus (EMCV). Mrasal protein operates as an antiviral host factor and confers a flavivirus specific resistance at the cellular level. It could be directly used for the treatment-cure of acute flavivirus infections in vivo. Our aims are to produce and purify the Mrasal protein for the in vivo delivery as a therapeutic compound into susceptible mice during the acute phase of flavivirus infection: 1. To synthesise and purify Mrasal protein using baculovirus system. 2. To encapsulate the protein into liposomes ready to be used in mice. 3. To perform initial testing in a limited number of susceptible mice.Read moreRead less