“Alpha-Galactosylceramid is a strong adjuvant for a genetic influenza vaccine.”

SANCHEZ, VICTORIA; CARGNELUTTI, DIEGO; SCODELLER EDUARDO

Mendoza

Congreso; 26º Reunion anual de la Sociedad de Biología de Cuyo; 2010

Sociedad de Biología de Cuyo

“Alpha-Galactosylceramid is a strong adjuvant for a genetic influenza vaccine”   Sanchez,MV; Cargnelutti,D; Scodeller E.IMBECU-CCT-Mendoza. Email:vsanchez@mendoza-conicet.gov.ar            Genetic immunization with naked DNA of genes encoding specific antigens has been used since approximately 20 years now, however high-titer humoral immune response are rarely seen using this strategy. For this approach to be successful the development of new adjuvants are urgently needed. It has been recently demonstrated that alpha-Galactosylceramide (á-GC) can act as a powerful vaccine adjuvant inducing protective immune responses against viral infection and tumors. The aim of this work was to evaluate the adjuvant effect of á-GC on a genetic vaccine using as immunogen DNA of the influenza nucleoprotein gene. Groups of 5 Balb/c mice were intramuscular immunized with 50 µg of plasmid encoding the influenza nucleoprotein under the CMV promoter formulated with 2 µg of á-GC (experimental group) or without á-GC (control group).  On day 14 all mice receive a boost with the same amount of DNA without á-GC. On day 35, serum samples were collected to evaluate the specific titer of total IgG, IgG1 and IgG2a isotypes. The titer of total IgG anti-NP was incremented 10 fold in the á-GC compared to the control group. The isotype predominately in these sera was IgG2a. This study clearly demonstrates that á-GC is a strong adjuvant for genetic immunization inducing much higher titers than those obtained unadjuvanted DNA.