DEVELOPMENT OF AN ORAL VACCINE PLATFORM WITH SURFACE PROTEINS FROM Giardia lamblia

RUPIL, LL; GARGANTINI, PR; ÑANCUFIL, FA; FASSOLA, LA; ALBRIEU-LLINÁS, G; SERRADELL , MC

Modalidad virtual

Encuentro; XXIII ANNUAL MEETING OF THE ARGENTINEAN BIOLOGY SOCIETY (SAB); 2021

SOCIEDAD ARGENTINA DE BIOLOGÍA

Overwhelming evidence demonstrates the benefits of immunization as one of the most successful and cost-effective health interventionsachieved to date. Although parenteral immunization is generally effective in eliminating systemic infections, it often fails to establishprotective responses on mucosal surfaces, where most infectious agents initiate infection. Mucosal vaccines target the common mucosalimmune system and achieve a more complete protective immune response by conferring both local and systemic immunity. Oralimmunization is the form most widely used of the mucosal vaccines due to its ease of administration. However, to achieve properbioavailability oral vaccines must avoid antigen degradation by digestive proteases. We have recently developed a vaccine platform thatleverages the properties of Giardia lamblia’s variant-specific surface proteins (VSPs) to allow oral immunization of subunit vaccines.VSPs cover the entire surface of this parasite that inhabits the upper gastrointestinal tract where digestive enzymes have their highestconcentration. Since VSPs have outstanding resistance to proteases and to changes in pH, high immunogenicity, and absence of toxicity,we engineered them to accommodate at a virus-like particle (VLP) and demonstrated that they could confer protection to a viral antigendisplayed on the particle. As a proof of concept, mice were orally immunized with VLPs containing glycoproteins of influenza virus andVSP1267. Immunized mice generated an efficient humoral and cellular, mucosal and systemic immune response that protected themfrom infection with the virus and from tumors expressing viral antigens. These exciting results prompted us to study the application ofthis platform as a potential vaccine for several other viruses. In conclusion, this novel vaccine platform provides new opportunities inthe field of vaccine technology to ultimately achieve more efficient vaccines with better patient compliance