Alphavirus-Based Vaccines

Lundstrom, Kenneth

Recently, VEE replicon particles generated in Vero cells were used to express the E2 glycoprotein of bovine viral diarrhea virus (BVDV) [23] . Vaccination of BVDV free calves with 1 × 10 6 IU and 1 × 10 7 IU, respectively, resulted in neutralizing antibody titers, which were able to cross-neutralize both type 1 and type 2 BVDV genotypes after booster immunizations. Vaccination with the higher dose significantly reduced the viral-based leukopenia and showed some protection from clinical disease. Similarly, VEE replicon particles were engineered to express Dengue virus E antigen in two configurations as subviral particles (prME) and soluble dimers (E85) [27] . Immunization of macaques resulted in the rapid production of neutralizing antibodies and demonstrated protection against challenges with Dengue virus. Moreover, the tetravalent E85 VEE replicon particle vaccine induced a protective response to all four Dengue virus serotypes when two immunizations were administered six weeks apart.