J Vet Sci.  2013 Dec;14(4):441-447. 10.4142/jvs.2013.14.4.441.

Codon optimization of the rabbit hemorrhagic disease virus (RHDV) capsid gene leads to increased gene expression in Spodoptera frugiperda 9 (Sf9) cells

• Gao J
• Meng C
• Chen Z
• Li C
• Liu G

• KMID: 1712311
• DOI: http://doi.org/10.4142/jvs.2013.14.4.441

Abstract

Rabbit hemorrhagic disease (RHD) is contagious and highly lethal. Commercial vaccines against RHD are produced from the livers of experimentally infected rabbits. Although several groups have reported that recombinant subunit vaccines against rabbit hemorrhagic disease virus (RHDV) are promising, application of the vaccines has been restricted due to high production costs or low yield. In the present study, we performed codon optimization of the capsid gene to increase the number of preference codons and eliminate rare codons in Spodoptera frugiperda 9 (Sf9) cells. The capsid gene was then subcloned into the pFastBac plasmid, and the recombinant baculoviruses were identified with a plaque assay. As expected, expression of the optimized capsid protein was markedly increased in the Sf9 cells, and the recombinant capsid proteins self-assembled into virus-like particles (VLPs) that were released into the cell supernatant. Rabbits inoculated with the supernatant and the purified VLPs were protected against RHDV challenge. A rapid, specific antibody response against RHDV was detected by an ELISA in all of the experimental groups. In conclusion, this strategy of producing a recombinant subunit vaccine antigen can be used to develop a low-cost, insect cell-derived recombinant subunit vaccine against RHDV.

Keyword

capsid protein; codon optimization; rabbit hemorrhagic disease; Spodoptera frugiperda 9 cells

MeSH Terms

Animals
Antigens, Viral/genetics/metabolism
Caliciviridae Infections/prevention & control/*veterinary/virology
Capsid Proteins/*genetics/metabolism
Cell Culture Techniques/*methods
Codon/genetics/metabolism
Enzyme-Linked Immunosorbent Assay/veterinary
*Gene Expression Regulation, Viral
Hemorrhagic Disease Virus, Rabbit/*genetics/immunology
*Rabbits
Recombinant Proteins/genetics/metabolism
Sf9 Cells
Spodoptera
Viral Structural Proteins/*genetics/metabolism
Viral Vaccines/genetics/immunology
Antigens, Viral
Capsid Proteins
Codon
Recombinant Proteins
Viral Structural Proteins
Viral Vaccines