Characterization and optimization of a nanoparticle-based vaccine

CHAVERO, CAMILA; BIANCHI, DAIANA; RIZZO, GASTON; APUZZO, EUGENIA; HERRERA, SANTIAGO; AGAZZI, MAXIMILIANO; CORTEZ, LORENA; MARMISOLLÉ, WALDEMAR; AZZARONI, OMAR; DOCENA GUILLERMO H; SMALDINI PAOLA LORENA

Congreso; SAIC ? SAI-FAIC- SAFIS; 2022

Nanotechnology is a significant breakthrough and represents an area of research that has been expanding in recent decades. Nowadays, nanoparticles play an important role in immunology and are being exploited to develop novel vaccines. Our group is working in the nanoscience field and we aimed to characterize different nanoparticles (Np) as adjuvants for mucosal and systemic vaccines.Different Np were characterized in terms of cell activation and production of cytokines by ELISA and flow cytometry and capacity of immune activation in mice. Balb/c mice were grouped and intraperitoneally immunized with OVA in combination with Np1 (VAC1) or Np2 (VAC2) at two different concentrations with a 3-week interval (Group 1 OVA; Group 2 VAC1 150 ug/ml; Group 3 VAC 1 60 ug/ml; Group 4 VAC2 150 ug/ml; Group 5 VAC2 60 ug/ml). Twenty-one days after the second dose, humoral (IgG, IgG1, IgG2a) and cellular (CD4, CD8, IFNγ) immune responses were evaluated by ELISA and Flow Cytometry, respectively.Cell line experiments showed that Np2 promoted significantly greater cell activation, with higher IL-1β secretion than Np1 and the positive controls for inflammasome activation. In vivo experiments showed that mice immunized with VAC2 presented higher levels of serum and bronchoalveolar lavage specific-OVA IgG than the other groups (p<0.05), with predominant production of specific IgG2a (p<0.05). Also, VAC2-vaccinated mice showed a higher frequency of LT CD4+IFN-γ+ and LT CD8+IFN-γ+ cells than the other groups (p<0,05).In conclusion, Np2 showed a superior profile of inflammasome activation compared to Np1 and VAC2 promoted immune induction at lower doses. These results are promising for developing therapeutic or preventive systemic and mucosal vaccines.