Virus like particles of the Junin Z protein (Z-VLP) bearing eGFP as a model antigen

PASTORINI MERCEDES; MARINA SCARFO; AGUSTÍN F DE GANZÓ; CRISTINA SILVIA BORIO; SANDRA GOÑI; DUARTE ALEJANDRA; MERCEDES ALEMÁN

Mar del Plata, Buenos Aires

Congreso; LXIV Reunión Anual de la Sociedad Argentina de Investigación Clínica; 2019

Virus-like particles (VLPs) are multiproteic nanostructures that mimic the organization and conformation of authentic viruses. Due to their lack of genome, these particles are incapable of infection or self-replication, yet maintain the efficient antigenicity required for the development of an immune response. Thus, VLPs are often included into vaccine formulations and at present, several licensed vaccines based on VLPs are already being used clinically against pathogens. The matrix protein Z of arenaviruses plays an important role in the process of virus budding and it is able to induce the generation of VLPs in a cell culture, even in absence of viral infection. We have previously demonstrated that Z-eGFP-VLPs induce dendritic cell (DCs) maturation in vitro. The objective was to evaluate VLP ability to induce lymphocyte activation in vivo. To achieve that, Balb/C mice were immunized or not with Z-eGFP-VLPs intraperitoneally. After 5 days, mononuclear cells were fractioned from the spleens, labeled with CFSE and later they were incubated with DCs previously pulsed with Z-eGFP-VLPs or PBS. Fluorescence of CFSE (FL1) was evaluated by FACS over 50,000 events collected. Results showed that Z-eGFP-VLPs stimulate a specific proliferative response in Balb/C vaccinated mice compared to control mice (p< 0.05). Besides, contribution of CD4+ and CD8+ cells to Z-eGFP-VLPs induced proliferation seems to be equitable (p