NUSBLAT alejandro David
congresos y reuniones científicas
EXPRESSION OF HBSAG FROM DIFFERENT GENOTYPES TO IMPROVE THE EFFICACY OF THE CURRENT ANTI-HEPATITIS B VACCINE
NAIR EGUIBAR; PRISCILA PERAZZO; SORDELLI ANDREA; NICOLAS RODRIGUEZ; GALLEGO R; MOLINA R; SAQUIN J; B.C. NUDEL; RODRIGO H GONZÁLEZ; A. D. NUSBLAT; MARIA LUJAN CUESTAS
Mar del Plata
Congreso; LI Reunion Anual 2015; 2015
Sociedad Argentina de Investigacion Bioquimica y Biologia Molecular
Introduction: Phylogenetic analysis based on the comparison of complete HBV genomes has defined at least 8 genotypes (A-H) and several subgenotypes that display a characteristic geographic distribution and show differences in biological properties. Genotypes E and F are the most divergent among all genotypes within the a determinant (aminoacids 107-147 of HBsAg) and within the S gene, respectively. These features, together with the emergence of S-escape mutants, have raised concerns about the efficacy of the current genotype A-based vaccines on the African and American continent, where genotypes E and F are prevalent, respectively. Aims: To analyze the effect of the most divergent genotypes (E, F1b and F4) and their interaction with anti-HBs antibodies derived from vaccination with genotype A2.Methods: Genes for each genotype were cloned into the expression vector pPICZa and transformed into Pichia pastoris X-33. For detection of HBsAg, commercial ELISA assays were performed. VLPs were characterized and reactivity was assayed in vitro (TEM and DLS) and in silico.Results: High expression levels were obtained, and the resulting VLPs had a size of about 20 nm. Reactivity with anti-HBs antibodies was variable.Conclusions: Our results point out the pressing need to assess the incorporation of genotypes E/F-derived HBsAg vaccine in those endemic areas where such genotypes are prevalent.