Team:Slovenia/Conclusions

• We have demonstrated the power of modular building blocks approach of synthetic biology (IMMUNOBRICKS) for the rational design of vaccines
• We have designed a new type of vaccine against H. pylori based on chimeric flagellin that combines activation of innate and adaptive immunity in the same molecule
  • Chimeric flagellins were produced in bacteria, purified and characterized
  • Engineered flagellins activate TLR5 as opposed to the native H. pylori flagellin
  • three different implementations of chimeric flagellin vaccines were prepared
  • chimeric flagellin is localized at the bacterial surface
  • DNA construct based on chimeric flagellin activates TLR5 on neighboring cells (demonstration of the feasibility of introduction of DNA into epithelial cells to activate underlying dendritic cells)
• Antigen-TLR fusions are functional and their localization can be modulated by the selection of transmembrane segment
• Various DNA vaccine constructs have been successfully introduced by electroporation intramuscularly or subcutanelously and expression of the fusion protein in the target tissue in vivo was demonstrated

• Complete animal studies: demonstrate the profilactic efficiency of our vaccines to prevent colonization, and therapeutic value to eradicate existing infection as well as evaluate effects of vaccinations on histology of gastric mucosa……
• Demonstrate the efficiency of bacterial implementation of flagellin-like vaccine on lyophilized bacterial ghosts (more safe and stable vaccine), particularly for oral and mucosal vaccination – prospects for application in third world countries
• Analyze different combinations of antigen-TLRs to obtain optimal immune stimulation (TLR synergy)
• Repeat all experiments with many controls, in comparison to currently used adjuvants etc

Prospects

• Functional vaccine against H. pylori would be definitely welcome
• The approach with chimeric flagellins could be used against other flagellated bacteria whose flagellin does not activate innate system (Bartonella, Campylobacter, Borellia...)
• Could vaccines based on antigen-TLR fusions be used as tumor vaccines as well?
• ... ... (ars longa, vita brevis)
• Two chimeric recombinant protein vaccines showed intense IgG antibody response in mice and immunized sera also reacted with heat-killed H. pylori antigens implying that they recognize epitopes of H. pylori.