INVESTIGADORES
RODRIGUEZ Ana Maria
congresos y reuniones científicas
Título:
Comparison of the celular immune response induced in Balb/c mice against Env of the more prevalent HIV variants in Argentina, Subtipe B and CRF_12BF
Autor/es:
MÓNACO,D; PASCUTTI,MF; ANA MARÍA RODRIGUEZ; CAROBENE,M; NAJERA,JL; ESTEBAN,M; SALOMÓN,H; GHERARDI,MM
Lugar:
Ciudad del Cabo-Sud Africa
Reunión:
Conferencia; AIDS Vaccine 2008 conference; 2008
Resumen:
Genetic diversity of HIV is one of the many obstacles in the development of a vaccine. In Argentina, infections are caused principally by subtype B and BF recombinants in similar proportions. To study cross-immunity between these two strains, we evaluated the immune response generated against Env by DNA and recombinant Vaccinia virus (rVV) vectors expressing EnvB or EnvBF. We used different immunization schemes in Balb/c mice that consisted in one or two doses of each rVV and a prime-boost (DNA/rVV) regime. All these vectors were previously generated using sequences derived from the CRF12_BF or the IIIB/LAI strains. Twelve days after the second immunization, we analyzed the specific cellular immune response stimulating the splenocytes with the full consensus subtype B gp120 protein or pools of overlapping peptides that represented the conserved and variable regions of this protein. Determinations were made by ELISPOT and by quantifying specific IFN-ã in the supernatant of splenocyte-cultures. Levels of immune response were significantly higher and broader when we used the prime-boost regime. In this immunization scheme, splenocytes of mice immunized with EnvB recognized peptides from almost all regions tested while the cellular response in those immunized with EnvBF was significant only for the two first conserved regions of gp120 (aa 1-123 and aa 197-299) and gp41 (aa 509-595), although the magnitude was lower than that for the homologous subtype. For all the immunization schemes used, the first conserved region of gp120 – showing the highest homology between subtypes - induced the highest response with vectors of both strains. Also, cellular response to the full gp120 protein was two-fold higher when mice were immunized with the homologous strain to this protein.        These results show that the impact of BF variants in the design of future vaccines is an issue that merits more deep analysis.