Balancing Immunogenicity of a Tetravalent Live Attenuated Dengue Vaccine

DESCRIPTION provided by applicant Dengue virus DENV infections are the leading mosquito borne human viral diseases in the world with billion people at risk of infection The diseases caused by DENV range from a self limiting Dengue fever DF to the life threatening hemorrhagic DHF and capillary leak syndrome Dengue shock syndrome DSS DENV accounts for possibly million infections cases of DHF DSS and deaths annually Despite large investment both public and private into the construction of an anti DENV vaccine one capable of protection has never materialized These previous attempts have relied on standard methods for vaccine construction however unique properties of DENV pathogenesis have rendered the use of andquot standardandquot approaches for vaccine development ineffective In light of this reality now is the time to pursue new methods and evaluate the efficacy of a DENV vaccine produced by novel approaches In this proposal we will apply our synthetic biology based vaccine development platform andquot Synthetic Attenuated Virus Engineeringandquot SAVE to begin the construction of a vaccine for DENV SAVE uses computer based software to andquot re codeandquot the genome of any target virus in such a way that the disease causing potential of the target is irrevocably disabled All human viruses must use the human host cell machinery to translate their genomes SAVE digitally andquot re codesandquot the virusandapos s genome by inserting hundreds of silent mutations and these changes put the genome into a genetic andquot languageandquot that is translated slowly by the human host cell These mutations render the resulting virus strain avirulent due to slowed host cell translation yet at the protein level the SAVE designed virus is INDETICAL to the target wild type strain yielding a highly immunogenic vaccine In animal models SAVE weakened viruses have proven extremely useful as vaccines against multiple unrelated viruses such as poliovirus and Influenza A virus In a pilot study we have successfully applied SAVE to serotype DENV in vitro In this study we seek to expand the application of SAVE to the other three DENV serotypes and Once the genomes of these additional serotypes have been andquot re codedandquot the corresponding viral genomes will be synthesized transfected into cell and replicating attenuated virus will be recovered These SAVE attenuated DENV viruses will then be formulated into a tetravalent vaccine and characterized in vitro growth in tissue culture cells and attenuation and immunogenicity in vivo ICR neonates and AG adult mice PUBLIC HEALTH RELEVANCE Dengue virus DENV infections are the leading mosquito borne human viral disease globally with billion people at risk and infections annually Despite large investment over decades both public and private an effective vaccines has remained elusive Here we will overcome limitations of previous dengue vaccine developments by employing a novel synthetic biology method that allows for the more precise balancing of the immune response against the four individual serotypes in a new tetravalent dengue vaccine