T cell-inducing heterologous vaccine against elephant endotheliotropic herpesvirus

We developed a heterologous, recombinant modified vaccinia virus Ankara prime and adjuvanted protein boost vaccine, containing the regulatory protein EE2 and the major capsid protein. The vaccine design focussed on targeting Th1 and cytotoxic T cell responses, which are crucial to herpesvirus immunity. In a proof-of-concept trial, safety and immunogenicity were tested in adult elephants. We used a modified interferon-γ release (IFNG) point-of-care vaccine-specific whole blood assay to determine T cell responses by RT-qPCR first, established to overcome quality-reducing sample transport times to the laboratory. Subsequently, RNA sequencing was utilised to understand transcriptomic changes induced by the vaccine. Blood samples before and after vaccination were taken for RNASeq. Samples were tested both unstimulated and Ag stimulated.