Development of a Japanese encephalitis virus-like particle vaccine in silkworms using codon-optimised prM and envelope genes

Abstract

We have successfully prepared a Japanese encephalitis virus (JEV) − Nakayama virus like particle (NVLP) vaccine using synthetic codon-optimized prM and E genes. The expression of the recombinant JEV Nakayama-BmNPV (JEV-NNPV) virus was determined in infected silkworm Bm-N cells by fluorescence and Western blot analysis. The recombinant was inoculated into silkworm pupae and the yield of Nakayama VLP (NVLP) reached a peak in the homogenates after 3 days. Additionally, in the peptide analysis of infected pupae homogenate, it appeared approximately 300–500 μg E protein/pupa were produced. When purified the above eluates on the discontinuous sucrose density gradient centrifugation, NVLP showed a strong hemagglutination (HA) activity by using chicken red blood cell in phosphate-buffered saline (PBS) free from Mg++ and Ca++ ions. The immune antisera against NVLP strain could efficiently neutralize the plaque formation of Nakayama, Beijing-1 and Muar strains, showing tendency of much higher reaction with heterologous Muar strain than homologous Nakayama strain. Our findings suggest that the JEV-NVLP may be useful for JEV epidemic control in many endemic areas of Asian countries as a widely effective and less expensive JE vaccine.

Virus-Like Particles With FLAG-Tagged Envelope Protein as A Tetravalent Dengue Vaccine Candidate

“…In this study, we demonstrated an effective strategy to produce DENV VLPs containing the FLAG tag and to concentrate and purify them with one-step chromatography. Characteristic features of puri ed VLP such as particle size, shape and density were basically comparable to avivirus like particles reported previously 12,20,21 . The tetravalent dengue vaccine candidate, which consisted of puri ed VLPs derived from DENV-1 to DENV-4, was found to induce neutralizing responses against all serotypes of DENV.…”

Recent Advances in the Development of Virus-Like Particle-Based Flavivirus Vaccines

“…VLP-based JEV vaccines are able to induce protection against infection of divergent JEV strains. Nerome et al developed a Nakayama JE VLP in silkworms using codon-optimized prM and E genes, and the VLPs showed protection against both homologous and heterologous strains (Beijing-1 and Muar) [ 110 ]. The same group successfully generated a Muar JE VLP vaccine in silkworm pupae through codon optimization of E gene [ 111 ].…”

Virus-Like Particle Systems for Vaccine Development against Viruses in the Flaviviridae Family

“…Following the above discoveries, several other groups also expressed plasmid vectors encoding JEV prME genes to produce JEV VLPs in different mammalian cells, yielding similar immunogenicity/protection in mice [42,43]. On the other hand, many groups have also successfully used the insect cell expression system to generate JEV VLPs [44][45][46][47][48]. However, the immunogenicity of the insect cell-derived JEV VLPs has not been generally tested in animals, except for the study by Matsuda et al in which silkworm-derived JEV VLPs were shown to be immunogenic in rabbits [48].…”

“…On the other hand, many groups have also successfully used the insect cell expression system to generate JEV VLPs [44][45][46][47][48]. However, the immunogenicity of the insect cell-derived JEV VLPs has not been generally tested in animals, except for the study by Matsuda et al in which silkworm-derived JEV VLPs were shown to be immunogenic in rabbits [48].…”