The first objective is to improve the properties of cell permeable peptides, CPPs, in order to apply them in gene therapy; by application of rational design based on evaluation of Structure Activity Relationships, SAR, from existing and newly discoverd CPP analogs. The second objective is to study the mechanisms of cellular uptake of CPPs in order to define the rules behind cellular uptake and selective uptake for oligonucleotides delivery. The third objective is to improve the CPP properties with respect to targeting cargo to specific tissue/intracellular compartments by screening combinatorial libraries and via attachment of "addresses" in order to achieve selective delivery of oligonucleotides. The fourth objective is the application of CPPs with oligonucleotide cargos and the study of the effects of these on biological function in vitro and in vivo.
The cell membrane penetrating peptides, CPPs, are designed and synthesized recently by the partners, and applied for cellular delivery of oligonucleotides. The aim of the present project is the design, synthesis and testing of novel non-viral modes of efficient target selective transport vectors based on CPP strategy for delivery of DNA single and double strand cargos and applications in gene therapy. For that, the mechanisms of cell penetration of CPPs will be studied. Specific tissue, cell and subcellular compartment targeting CPPs will be developed for application in gene therapy. The libraries of CPPs will be synthesised and tested with combination of iterative approach and high throughput screening. The biological effects of successful oligonucleotide delivery systems will be detected in vitro and in vivo, and used in a high-throughput assay of CPP optimisation.