The sequences of the stabilized pre-fusion NiV F glycoprotein with a C-terminal GCN4 domain-3C cleavage site-8× His tag-twin Strep tag and the soluble head domain of NiV G with C terminal 3C cleavage site-8× His tag-twin Strep tag were cloned into pEEV plasmid by Twist Bioscience. The proteins were expressed in Expi293F cells growing in Expi293 expression medium via transient transfection using FectoPro according Polyplus recommendations. Cells were transfected with 0.8 μg plasmid/ml of culture using 1.5 μl of transfection reagent/μg of the plasmid. Four to 6 days after transfection, culture supernatants were clarified, filtered, and loaded onto the HisTrap Excel column. NiV F and G proteins were further purified via size exclusion chromatography. Following purification, proteins were quantified and stored at −80°C.

Nipah virus (NiV) causes a highly lethal disease in humans who present with acute respiratory or neurological signs. No vaccines against NiV have been approved to date. Here, we report on the clinical impact of a novel NiV-derived nonspreading replicon particle lacking the fusion (F) protein gene (NiVΔF) as a vaccine in three small animal models of disease. A broad antibody response was detected that included immunoglobulin G (IgG) and IgA subtypes with demonstrable Fc-mediated effector function targeting multiple viral antigens. Single-dose intranasal vaccination up to 3 days before challenge prevented clinical signs and reduced virus levels in hamsters and immunocompromised mice; decreases were seen in tissues and mucosal secretions, critically decreasing potential for virus transmission. This virus replicon particle system provides a vital tool to the field and demonstrates utility as a highly efficacious and safe vaccine candidate that can be administered parenterally or mucosally to protect against lethal Nipah disease.