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Development of plant-produced Bluetongue virus vaccines

Bluetongue is a disease of domestic and wild ruminants caused by Bluetongue virus (BTV). It has caused several serious outbreaks, the most recent occurring in Northern Europe in 2006 during which high mortality rates of livestock were reported. The only vaccines currently approved and commercially a...

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Main Author: van Zyl, Albertha R
Other Authors: Meyers, Ann
Format: Thesis
Language:English
Published: Department of Molecular and Cell Biology 2018
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access_status_str Open Access
author van Zyl, Albertha R
author2 Meyers, Ann
author_browse Meyers, Ann
van Zyl, Albertha R
author_facet Meyers, Ann
van Zyl, Albertha R
author_sort van Zyl, Albertha R
collection Thesis
description Bluetongue is a disease of domestic and wild ruminants caused by Bluetongue virus (BTV). It has caused several serious outbreaks, the most recent occurring in Northern Europe in 2006 during which high mortality rates of livestock were reported. The only vaccines currently approved and commercially available for use are live-attenuated or inactivated virus strains and although these are effective, there is the risk of reversion in the case of live-attenuated strains to more virulent forms by recombination. Another drawback associated with the use of live-attenuated virus vaccines is that they are not DIVA (differentiate infected from vaccinated animals) compliant, this means that naturally infected animals cannot be distinguished from vaccinated animals. Recombinantly produced vaccines would be preferable to minimize the risks associated with live-attenuated virus vaccines and also enable the development of candidate vaccines that are DIVA-compliant. A number of recombinant vaccine candidates have been developed against BTV, with the most promising vaccine consisting of BTV virus-like particles (VLPs). BTV VLPs were successfully produced in insect cells by the co-expression of the four BTV capsid proteins (VP2, VP3, VP5 and VP7). Sheep vaccinated with insect cell-produced BTV VLPs were shown to be protected against challenge with wild type virus. However, the high costs associated with the production and scale-up of BTV VLPs in insect cells has possibly limited their widespread application. Plants – such as N. benthamiana – provides a safe, efficient and cost effective system for the production of recombinant proteins. In this study the best plant expression vector with which to co-express the four BTV serotype 8 (BTV-8) VPs – which direct formation of BTV-8 VLPs – was identified. Expression and purification of the BTV-8 VLPs was optimised with the aim of producing a VLP-based vaccine for BTV-8. It was further undertaken to develop two novel second generation plant-produced protein body (PB) vaccines that are DIVA compliant. Mice were immunised with the plantproduced VLP and PB vaccines in order to analyse their ability to elicit humoral immune responses.
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institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:32:11.035Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2018
publishDateRange 2018
publishDateSort 2018
publisher Department of Molecular and Cell Biology
publisherStr Department of Molecular and Cell Biology
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source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/28248 Development of plant-produced Bluetongue virus vaccines van Zyl, Albertha R Meyers, Ann Rybicki, Edward P Molecular and Cell Biology Bluetongue is a disease of domestic and wild ruminants caused by Bluetongue virus (BTV). It has caused several serious outbreaks, the most recent occurring in Northern Europe in 2006 during which high mortality rates of livestock were reported. The only vaccines currently approved and commercially available for use are live-attenuated or inactivated virus strains and although these are effective, there is the risk of reversion in the case of live-attenuated strains to more virulent forms by recombination. Another drawback associated with the use of live-attenuated virus vaccines is that they are not DIVA (differentiate infected from vaccinated animals) compliant, this means that naturally infected animals cannot be distinguished from vaccinated animals. Recombinantly produced vaccines would be preferable to minimize the risks associated with live-attenuated virus vaccines and also enable the development of candidate vaccines that are DIVA-compliant. A number of recombinant vaccine candidates have been developed against BTV, with the most promising vaccine consisting of BTV virus-like particles (VLPs). BTV VLPs were successfully produced in insect cells by the co-expression of the four BTV capsid proteins (VP2, VP3, VP5 and VP7). Sheep vaccinated with insect cell-produced BTV VLPs were shown to be protected against challenge with wild type virus. However, the high costs associated with the production and scale-up of BTV VLPs in insect cells has possibly limited their widespread application. Plants – such as N. benthamiana – provides a safe, efficient and cost effective system for the production of recombinant proteins. In this study the best plant expression vector with which to co-express the four BTV serotype 8 (BTV-8) VPs – which direct formation of BTV-8 VLPs – was identified. Expression and purification of the BTV-8 VLPs was optimised with the aim of producing a VLP-based vaccine for BTV-8. It was further undertaken to develop two novel second generation plant-produced protein body (PB) vaccines that are DIVA compliant. Mice were immunised with the plantproduced VLP and PB vaccines in order to analyse their ability to elicit humoral immune responses. 2018-06-12T14:26:15Z 2018-06-12T14:26:15Z 2014 Doctoral Thesis Doctoral PhD http://hdl.handle.net/11427/28248 eng application/pdf Department of Molecular and Cell Biology Faculty of Science University of Cape Town
spellingShingle Molecular and Cell Biology
van Zyl, Albertha R
Development of plant-produced Bluetongue virus vaccines
thesis_degree_str Doctoral
title Development of plant-produced Bluetongue virus vaccines
title_full Development of plant-produced Bluetongue virus vaccines
title_fullStr Development of plant-produced Bluetongue virus vaccines
title_full_unstemmed Development of plant-produced Bluetongue virus vaccines
title_short Development of plant-produced Bluetongue virus vaccines
title_sort development of plant produced bluetongue virus vaccines
topic Molecular and Cell Biology
url http://hdl.handle.net/11427/28248
work_keys_str_mv AT vanzylalberthar developmentofplantproducedbluetonguevirusvaccines