Establishment of a neutralization assay for Nipah virus using a high-titer pseudovirus system

Biotechnol Lett. 2023 Apr;45(4):489-498. doi: 10.1007/s10529-023-03351-5. Epub 2023 Jan 21.

Abstract

Objective: To construct a high-titer Nipah pseudovirus packaging system using the HIV lentivirus backbone vector and establish a safe neutralization assay for Nipah pseudovirus in biosafety level 2 facilities.

Methods: Nipah virus (NiV) fusion protein (F) and glycoprotein (G) recombinant expression plasmids, psPAX2, and pLenti CMV Puro LUC (w168-1) were transiently transfected into 293T cells for 72 h for the generation of a NiV pseudovirus. The neutralization ability of Nipah virus F and G protein antibodies was assessed using the pseudovirus.

Results: A NiV pseudovirus was constructed using 293T cells. The ideal mass ratio of plasmid psPAX2: w168-1: F: G for transfection was determined to be 4:4:1:1. The specificity of recombinant F and G protein expression was indicated by indirect immunofluorescence and western blotting. The pseudovirus particles showed obvious spikes under a transmission electron microscope. The NiV pseudovirus titer was 4.73 × 105 median tissue culture infective dose per mL, and the pseudovirus could be effectively neutralized by polyclonal antibodies specifically targeting the F and G proteins respectively.

Conclusions: A NiV pseudovirus was successfully generated using HIV vector systems, and was used as a platform for a safe and reliable pseudovirus-based neutralizing assay that can be performed in biosafety level 2 facilities.

Keywords: Fusion protein; Glycoprotein; Neutralization assay; Nipah virus; Pseudovirus.

MeSH terms

  • Antibodies
  • Blotting, Western
  • HIV Infections*
  • Humans
  • Nipah Virus* / genetics
  • Plasmids
  • Transfection

Substances

  • Antibodies