Leishmania tarentolae as a vaccine platform: efficacy as antigen vehicle, oral administration, and extent and duration of the immune response (LETAVOIR)

Our previous studies confirm that L. tarentolae (Lt) holds a great potential in vaccinology: (i) as a vaccine platform, for the production of viral antigens; (ii) as a vaccine vehicle, for the delivery of the antigen to dendritic cells and macrophages (i.e., to the cell that trigger and govern the development of the immune response). The overall goal of this proposal is to further develop Lt as a vaccine platform and vehicle for a mucosal vaccination. To this purpose, using strains of Lt engineered to the expression of viral antigens, LETAVOIR project will pursue the following specific objectives: • AIM1: to develop preparations of engineered Lt strains, suitable for storage a room temperature (or refrigerated) and for administration through the oral route (through freezing-drying procedures). • • AIM2: to determine the duration of the immune response against viral antigens, after vaccination with engineered Lt strains. • AIM3: to determine whether a previous immunization against Lt interferes with the magnitude of the immune response against viral antigens expressed by engineered strains of Lt, in a successive vaccination. As detailed in the background section, the project will be developed using SARS-CoV-2 as a model virus, and the strains of Lt that we already engineered for the expression of antigens from this virus.