Mosquito Cell-Derived Japanese Encephalitis Virus-Like Particles Induce Specific Humoral and Cellular Immune Responses in Mice

Abstract

The Japanese encephalitis virus (JEV) is the major cause of an acute encephalitis syndrome in many Asian countries, despite the fact that an effective vaccine has been developed. Virus-like particles (VLPs) are self-assembled multi-subunit protein structures which possess specific epitope antigenicities related to corresponding native viruses. These properties mean that VLPs are considered safe antigens that can be used in clinical applications. In this study, we developed a novel baculovirus/mosquito (BacMos) expression system which potentially enables the scalable production of JEV genotype III (GIII) VLPs (which are secreted from mosquito cells). The mosquito-cell-derived JEV VLPs comprised 30-nm spherical particles as well as precursor membrane protein (prM) and envelope (E) proteins with densities that ranged from 30% to 55% across a sucrose gradient. We used IgM antibody-capture enzyme-linked immunosorbent assays to assess the resemblance between VLPs and authentic virions and thereby characterized the epitope specific antigenicity of VLPs. VLP immunization was found to elicit a specific immune response toward a balanced IgG2a/IgG1 ratio. This response effectively neutralized both JEV GI and GIII and elicited a mixed Th1/Th2 response in mice. This study supports the development of mosquito cell-derived JEV VLPs to serve as candidate vaccines against JEV.

Japanese encephalitis genotype I virus-like particles stably expressed in BHK-21 cells serves as potential antigen in JE IgM ELISA

“…The correlation coefficient (R = 0.997) and P < 0.0001 indicating that the VLPs are antigenically equivalent to the native virus antigen preparations by detecting a good amount of VLPs in cell supernatant up to 40 passages. Considering all characteristics exhibited by the expressed VLPs, they can be explored as a vaccine as described earlier (Chang et al 2020;Fan et al 2018).…”

“…The long-term stability of the BHK-IE6 clone was established by detecting a good amount of VLPs in cell supernatant up to 40 passages. Considering all characteristics exhibited by the expressed VLPs, they can be explored as a vaccine as described earlier (Chang et al 2020 ; Fan et al 2018 ).…”

Development of a Novel Chikungunya Virus-Like Replicon Particle for Rapid Quantification and Screening of Neutralizing Antibodies and Antivirals

“…Vero cells (1.5 × 10 4 cells/well) were seeded in a 96-well white/clear-bottomed plate (Thermo Scientific Nunc). VRPs were preincubated with serially diluted NT MAbs (CHK-265 [Absolute Biotech] and 3E7B [Novus Biologicals]), as well as sera from patient and inactivated CHIKV-immunized rabbit ( 45 ) at 37°C for 1 h. 6B6C MAb (a flavivirus NT antibody [ 47 ]), as well as sera from a normal individual and the preimmune rabbit, were used as the negative control. The cells were incubated overnight, washed with growth medium, infected with preincubated VRPs (2,500 IU/well), and incubated at 34°C for 1 h, whereupon the medium was refreshed to continue incubation at 34°C for another 5 h; then the cells were subjected to Luc assay.…”

Virus-like particles vaccines based on glycoprotein E0 and E2 of bovine viral diarrhea virus induce Humoral responses

“…The VLPs based on BEVS have been successfully generated for many members of Flaviviridae , including hepatitis C virus (HCV; Elmowalid et al, 2007 ), dengue fever virus (DENV; Suphatrakul et al, 2015 ), Zika virus (ZV; Dai et al, 2018 ), West Nile virus (WNV; Rebollo et al, 2018 ), Japanese encephalitis virus (JEV; Chang et al, 2020 ). As a member of Flaviviridae , VLPs of BVDV have also been reported by Bolin and Ridpath (1996) and Wang et al (2021) .…”