Comparison of Strategies for the Production of FMDV Empty Capsids Using the Baculovirus Vector System

Abstract

Recombinant FMDV empty capsids have been produced in insect cells and larvae using the baculovirus expression system, although protein yield and efficiency of capsid assembly have been highly variable. In this work, two strategies were compared for the expression of FMDV A/Arg/01 empty capsids: infection with a dual-promoter baculovirus vector coding for the capsid precursor (P12A) and the protease 3C under the control of the polyhedrin and p10 promoters, respectively (BacP12A-3C), or a single-promoter vector coding the P12A3C cassette (BacP12A3C). Expression levels and assembly into empty capsids were analyzed in insect cells and larvae. We observed that the use of the single-promoter vector allowed higher levels of expression both in insect cells and larvae. Recombinant capsid proteins produced by both vectors were recognized by monoclonal antibodies (mAbs) directed against conformational epitopes of FMDV A/Arg/01 and proved to self-assemble into empty capsids (75S) and pentamers (12S) when analyzed by sucrose gradient centrifugation.

Foot-and-Mouth Disease Virus: Immunobiology, Advances in Vaccines and Vaccination Strategies Addressing Vaccine Failures—An Indian Perspective

“…VLPs developed for an Indian vaccine strain protected guinea pigs against homologous challenge [83]. Several improvements have been made in the production of VLPs using the dual promoter vector, 3Cpro [84], or using a bicistronic complementary DNA cassette containing two open reading frames encoding an FMDV capsid gene (P1-2A) and 3Cpro separated by an internal ribosome entry site [85]. In another study, the mutation in the VP2 region increased the thermostability of VLPs and produced sufficient protection in guinea pigs [86].…”

Advanced Foot-And-Mouth Disease Vaccine Platform for Stimulation of Simultaneous Cellular and Humoral Immune Responses

“…Currently, FMD vaccine studies using an inactivated vaccine, modified virus inactivated vaccine (DIVA vaccine) [ 24 ], viral vector vaccine [ 25 ], adenovirus [ 26 , 27 , 28 ], virus-like particle (VLP) vaccine (bacterial) [ 29 ], baculovirus [ 30 , 31 ], plant-produced empty capsids [ 32 , 33 ], peptide vaccine (Poly(I:C)) [ 34 ], CpG [ 35 ], plant based recombinant vaccine (alfalfa [ 36 ], chloroplast of tobacco [ 37 ]), RNA vaccine [ 38 ], DNA vaccine (cDNA [ 39 , 40 ], electroporation [ 41 ], T cell [ 42 , 43 , 44 ], B cell [ 45 , 46 ] epitope, APC targeting [ 47 ]), live attenuated vaccine [ 48 , 49 , 50 , 51 ], and antiviral agent [ 52 , 53 ] are underway. However, no high-quality FMD vaccines that surpass the efficacy of the inactivated vaccine have been successfully developed to date.…”

Toward innovative veterinary nanoparticle vaccines

“…There are currently two forms of FMDV VLP vaccines: one composed of FMDV capsid proteins and one composed of chimeric FMDV VLPs created by incorporating critical epitopes from multiple serotypes. FMDV VLPs or chimeric VLPs can be efficiently expressed in E. coli, mammalian cells, and insect expression systems (Silva, et al 2013;Xiao, et al 2016;Oem, et al 2007;Felberbaum 2015;Ruiz, et al 2014;Gullberg, et al 2013). Previous research has shown that FMDV VLPs, as FMDV vaccines, can induce long-lasting humoral and cellular immune responses.…”