Plant-produced YFE-1T subunit vaccine against Yellow Fever induces humoral response in captive golden-headed lion tamarin (Leontopithecus chrysomelas)

Introduction: Yellow Fever (YF) is a mosquito-borne viral hemorrhagic fever with a case fatality rate up to 50%. It is endemic in the Brazilian Amazon region, and sporadic outbreaks take place outside the endemic area in Brazil. However, Brazil has recently experienced its largest recorded YF outbreak in decades, with 1,376 confirmed cases and 483 deaths in humans, and 864 confirmed epizooties in non-human primates (NHPs) from July 2017 to June 2018. Despite the excellent safety of YF 17DD vaccine, there are rare cases of serious adverse events, which are often fatal. According to described aspects, the risk of urban YF resurgence and the absence of a vaccine available for NHPs, there is a strong demand for the development of alternative YF vaccines that are safe and efficacious for disease control. Therefore, Bio-Manguinhos/Fiocruz, in collaboration with Fraunhofer USA Center for Molecular Biotechnology, has been developing a plant-derived recombinant subunit YF vaccine (YFE-1T) to address the global demand for increasing availability and safety of the YF vaccine. YFE-1T subunit composed by the ectodomain of the E protein was transiently expressed in Nicotiana benthamiana by Agrobacterium tumefaciens-mediated gene transfer, purified and adsorbed to aluminum hydroxide adjuvant.