VLPs-pseudotyped with Variant Surface Proteins of Giardia as an effective oral Influenza vaccine

SAURA ALICIA; LUJAN HUGO D.; RUPIL LUCIA L; OMS SERGIO R; SERRADELL MARIANELA DEL C; GARGANTINI PABLO R

Cordoba

Congreso; 52 th Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2016

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

 Oral vaccines possess attractive advantages over parenteral vaccines. However, there are certain drawbacks inherent to this form of immunization because the vaccinal antigen has to resist the passage through the upper gastrointestinal tract. Since Giardia Variant-specific Surface Proteins (VSPs) protect this parasite from the harsh environmental conditions of the intestine and have a remarkable intrinsic immunogenicity, we hypothesized that efficient oral vaccines can be generated by combining the benefits of Giardia VSPs as protective agents with the advantages of particulate immunogens like Virus-like Particles (VLPs). Here, we generated an Influenza A H5N1 VLPs pseudotyped with the extracellular domain of Giardia VSP1267 and orally immunized mice. When comparing to control VLPs without VSP1267, we found that the vaccines were able to induce the production of HA-specific antibodies in serum, as well as in mucosal fluids such as bronchoalveolar lavage and feces. When the different subtypes of IgG were analyzed in serum, it was found that both IgG1 as IgG2 showed a significant increase. In addition, a high number of IFNã secreting HA-specific cells were present in spleen and mesenteric lymph nodes. Protection assays with live Influenza virus confirmed the efficiency of this novel oral vaccine, paving the way for the design of oral vaccines to other human pathogens.