A versatile transkingdom platform for therapeutic nucleic acid delivery to mucosal epithelial tissues

PROJECT SUMMARYThe therapeutic applications of nucleic acidsNAshave strong potential for a wide range of disease targets but major obstacles to clinical application include short lived silencing effect and challenges in delivery to specific cells and tissuesDeveloping a delivery platform for targeted and stabilized intracellular delivery of RNAi mediating agents to specific tissues is essential to capitalizing on the therapeutic potential that NA based technologies hold for translational human medicineAs many allergens and viral and bacterial pathogens invade the body via mucosal tissuesthese sites represent an important target for delivery of NA based therapeuticsOur transkingdom delivery platform is characterized by nonpathogenic bacteria that constitutively generate shRNAs for targeted intracellular delivery to mucosal epithelial cells and RNAi silencing without genomic integrationThis platform theoretically overcomes challenges with delivery to specific cells and tissuesHoweververy few tissue types have been treated with this delivery vehicle and the short lived RNAi effect is still problematicTo build upon our existing NA delivery platform technology and the success it has demonstrated to datewe propose here to improve the RNAi properties of the platform for a prolonged silencing effect and demonstrate this delivery platformandapos s ability to target different tissues relevant to a wide range of clinical applicationsSpecificallywe will individually evaluate the shRNA stabilizing effects of a constitutively expressed dsRNA binding protein and methyltransferaseand an RNase R mutantOur specific aims are toImprove the shRNA stability and the RNAi silencing effects of the parent delivery platform through three approaches to be evaluated in vitroTest the delivery feasibilitysafetybiodistributionimmunogenicitytoxicityand RNAi silencing effect of each variant in mucosal epithelial tissues in vivoandEvaluate the therapeutic application of the delivery vehicle variants in an established in vivo disease modelTo accomplish this researchwe have assembled a multidisciplinary team with specialized experience in RNAibased antiviral developmentdevelopment of molecular methodsRNA regulation and metabolismpre clinical and clinical drug developmentand translational researchIf the proposed aims are achievedthis work will provide proof of concept for a therapeutically viable NA delivery platformand will highlight the feasibility of utilizing these transkingdom RNAi delivery vehicles to target clinically relevant mucosal epithelial tissues for a broad range of disease applicationsOur unique approach provides a new perspective on NA delivery and addresses many of the shortcomings associated with current NA delivery approachesOur delivery platform combines ingenuity with practicality and seeks to transform the field of NA therapeutics and RNAi into a clinical reality PROJECT NARRATIVEDespite the great promise that nucleic acids hold for therapeutic applicationlimitations in delivery to specific tissues and duration of effect remain major hurdles to clinical relevanceWe propose to overcome these obstacles by enhancing the stability and bioavailability of nucleic acids constitutively expressed by a transkingdom delivery vehicleand to demonstrate safe and specific uptakewithout concomitant toxicityinto a variety of target mucosal tissuesThis transkingdom delivery platform could provide a breakthrough in public health due to its tremendous therapeutic potential for a vast number of human diseases that affect a wide range of clinically relevant tissues