SCREENING FOR A PLASMID DNA CONSTRUCTION ASSOCIATED TO MOLECULAR ADJUVATS TO BE EMPLOYED IN A FOOT AND MOUTH DISEASE VIRUS (FMDV) DNA VACCINE

PEREYRA ERICA ; QUATTROCCHI VALERIA; LANGELLOTTI CECILIA; D´ANTUONO ALEJANDRA ; MATTION NORA; MONGINI CLAUDIA ; ZAMORANO PATRICIA

Congreso; Primer Congreso Franco Argentino de Inmunología (FAIC 2010); 2010

Sociedad Argentina de Inmunología, El Grupo rioplatense de citometría de flujo y Grupo de inmunología pediátrica de la SAP

The aim of this work was to construct eukaryotic plasmids encoding the polyprotein pP12A3C and the cytosolic (pVP1c) and secreted (pVP1s) form of FMDV O1Campos in combination or not with the molecular adjuvants pCD40L and pRANKL and to evaluate the immune efficacy of these DNA vaccinations in a murine model. The plasmids were cloned alone or together with molecular adjuvants, into the expression vector pCineo to be used as DNA vaccines. In vitro expression was evaluated by transfecting BHK cells and ascertained by flow cytometry or Western Blot. To examine their immunogenicity, 5 Balb/c mice per group were inoculated i.d, twice with the different DNA vaccines and a negative control group inoculated with pCineo. On day 7 after the second immunization, total antibodies against VP1 were detected by ELISA. The percentage of animals with a-VP1 titers range from 60 to 40% for the animals primed with the pP12A3C and pVP1s and co-inoculation of molecular adjuvants. Moreover, to evaluate the protective efficacy against viral challenge, the mice were infected with 104.5 TCID50 of O1/Campos FMDV strain on day 7 after the second immunization. We found that mice inoculated with pP12A3C displayed a higher degree of protection when compared with the mice primed with pVP1 (44% versus 19% for pP12A3C and pVP1 respectively; p<0.027); whereas negative group were non protected. One other hand, preliminary results indicate that pP12A3C together with molecular adjuvants induce a better protection than pP12A3C alone. This screening work demonstrated that pP12A3C proved to be more effective than pVP1 to protect the mice against a challenge with the FMDV even when both induced similar antibodies titers. Further repeat vaccination, route of inoculation, the combination and different proportions of the vaccines will be teste