international society for plant molecular farming ... ismp… · for recombinant protein expression...
TRANSCRIPT
Welcome to the special newsletter for the 8th International PBVAB conference, 10-12 June 2019, Riga, Latvia
The 8th PBVAB meeting was held at the University of Latvia and attracted 99 experts in plant molecular farming from 19 different countries.
The focus of the conference
was to offer an international
forum to review the current state
of research in plant-based protein
expression systems, down-
stream processing technology,
the pipeline of products now in
development (including vaccines,
monoclonal antibodies, and
human enzymes), and efforts in
using these technologies in areas
beyond human health (including
disease prevention in animals
and aquaculture).
PBVAB 2019 aimed to emphasise the take-off of the commercialisation of plant-based biologic products, the requirement for more academic-based research to respond to the question: “Where is the pipeline of products going to come from and what have we learned on the decision-making processes for that product pipeline?“
The meeting was held over 3 days
consisting of 9 sessions with 35
oral and 39 poster presentations.
ISPMF sponsored conference dinner at the National Library of Latvia
The ISPMF hosted a dinner on the first night of the meeting at the National Library of Latvia, Restorãns Klĩversala. This provided attendees with a valuable opportunity to relax, network and enjoy the local cuisine.
In this issue: P1: PBVAB 2019 conference statement
P2: ISPMF sponsored conference dinner at
PBVAB 2019
P3: Session 1, 2 & 3
P4: Session 4 & poster presentations
P5: Sessions 5 & 6
P6: Sessions 7, 8 & 9
P7: Special edition of Plants
P8: Upcoming meetings
INTERNATIONAL SOCIETY FOR PLANT MOLECULAR FARMING NEWSLETTER ISSUE 16 July 2019
8th International PBVAB conference dinner, Riga Library, Latvia
Attendees had an opportunity to network over dinner and drinks.
ISPMF NEWSLETTER | Issue 16 3
Welcome The meeting started with a brief welcome by Prof. Julian Ma (St George’s University) who reflected on the current state of the field. He highlighted the paradigm shift towards value driven, as apposed to volume driven pharmaceutical production. He stressed the potential of plant expression for smaller areas of medical need where flexible volumes were needed.
Session 1 The opening session of the meeting was about clinical trials of plant-produced products.
Dr. Frank Thieme from Icon Genetics GmbH (Germany) kicked-off the session
with a talk on the development of a plant-based bivalent Norovirus-like particle vaccine. He described the pre-clinical research phase to the establishment of the clinical program for the upcoming phase I trial. The presentation reported that plant-produced Norovirus VLPs elicited an immune response in mice without the need for an adjuvant. They are currently evaluating the stability and purity of their VLPs, and will start the phase I clinical trials early 2020.
This was followed by Dr. Daniel Tusé the managing director of Intrucept Biomedicine (USA), who presented on the progress of using the mannose-binding lectin - Griffithsin - as a microbicide for HIV. The data presented supports the initiation of a clinical program, as high yields of
good quality protein can be readily produced in the system. No adverse effects were observed in either rabbit or rat models.
The session was
concluded by Dr. Marc-André D’Aoust from Medicago (Canada) who described Medicago’s R & D pipeline. He stressed that Medicago uses the same platform from early stage development to large scale production. He also described the high throughput automation that had been implemented to enable screening of expression constructs. Other standout aspects of the talk were Medicagos monovalent Norovirus VLP vaccine development and the production of antibodies targetting Respiratory Syncytial virus.
Session 2 The primary focus of session 2 was on new product development.
Prof. Karen McDonald from the University of California Davis (USA) spoke about
advancements in using plant cell culture-based manufacturing platforms for the production of recombinant protein bioscavengers, in this case specifically against orthophosphate nerve agents and anthrax toxins. The data presented supported the use of plant cell culture systems as promising bioreactors for large scale recombinant protein production.
This was followed by an insightful talk from Dr. Anatoli Giritch from Nomad Bioscience GmbH (Germany) on the value of plant-
produced bacteriocins as food antimicrobials. They showed that both a cocktail of plant-produced colicins and salmocins eliminated pathogenic E. coli and Salmonella from meats, fish and fresh produce respectively. This represents a new class of products manufactured in a plant-production system.
The session was concluded with a two-part talk given by Tobias Schneider from Nomad Bioscience GmbH (Germany) and Šarūnas Paškevičius from Nomads UAB (Lithuania) about the engineering of chimaeric bacteriocins, trademarked Legocins, through domain shuffling. They demonstrated that both plant-produced intra- and interspecies Legocins™ are functional, providing a proof-of-concept for the engineering of cross-species bacteriocins -Legocins™.
Session 3 The final session of the day was about improved control of biopharming process conditions.
The session was opened by Dr. Johannes Buyel from Fraunhofer
IME (Germany), who presented a model for yield and variability prediction, based on weather data, for recombinant protein expression in plants that were maintained in a greenhouse. They found that even under controlled greenhouse conditions there was seasonal variability in the quality of expressed proteins. They also showed that cultivation conditions impacted their affinity of protein binding during purification, and contamination with host proteins.
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Continuing on the topic of the importance of a controlled cultivation
environment, Dr. Fabian Schvartzman from Aerofarms (USA) highlighted the advantages of vertical farming. Since vertical farming allows for a more tightly-controlled cultivation environment than greenhouses, there is a higher consistency in plant growth and yield. They have shown the ability to control the concentration of secondary metabolites by using this cultivation system, suggesting that the system is ripe for application to Molecular Farming industry.
Session 4 The topic of session 4 was on animal health.
Prof. Ed Rybicki from the University of Cape Town (South Africa) gave a keynote presentation on the work his research group is doing for the advancement of the ‘One Health’ Initiative. He highlighted that the group is student-centric and aims to generate intellectual property that can feed into industry. He reported on the successful production of a range of useful diagnostic reagents in plants, including a Crimean-Congo hemorrhagic fever virus nucleocapsid protein that reacted with human sera from infected donors.
This was followed by Prof. Ann Depicker from Ghent University (Belgium), who presented on behalf of her postdoc Dr. Vikram Virdi about the value of seed expression platforms for antibody production against gastroenteric E. coli. They showed that VHH-IgA antibodies produced in both Arabidopsis and Soybean seeds reduced bacterial shedding after oral administration of the seeds as a feed additive. This model highlights the possible translation of VHH-IgA to prevent human gastro-intestinal infections.
This work has recently been published in Nature Biotechnology as a brief communication: https://www.nature.com/articles/s41587-019-0070-x
“Now, research by Vikram Virdi, postdoc in the lab of Nico Callewaert (VIB-UGent) and Ann Depicker (VIB-UGent), makes oral to gut delivery of antibodies possible. The scientists engineered an antibody format that is simple but robust enough to survive the harsh environment in the gut. What is more, the team also developed a manufacturing process that uses either soybean seeds or yeast cells to produce these antibodies. By using existing food-processing technology they could eliminate the need for expensive purification processes. The result is an easily manufactured powder with antibodies that can be added to food and ingested orally, requiring no encapsulation.” www.vib.be
Dr. Eun-Ju Sohn from BioApplications Inc. (Korea) presented work they have done to develop a DIVA-compliant candidate
vaccine for classical swine fever virus (CSFV) produced in transgenic plants. High levels of immunogenicity were observed in piglets as well as protection when challenged with CSFV.
Poster Sessions
A total of 39 posters were presented at the conference. Poster topics included VLP, therapeutic and diagnostic reagent production in plants. Attendees had the opportunity to converse with presenters about their work throughout the conference.
Kaewta Rattanapisit from Chulalongkorn University (Thailand) presented on improved Osteopontin expression in planta through fusion to the Fc domain of human IgG1. Her data showed that plant produced OPN-Fc can stimulate osteogenic related genes.
ISPMF NEWSLETTER | Issue 16 5
Siphumelele Ndlovu from Cape Bio Pharms (South Africa) presented work from her MSc. based on phage-display technology. Shuni virus scFvs were successfully detected by phage-display and anti-shuni-scFvs were produced in N. benthamiana.
Dr. Veronique Beiss from the University of California San Diego (USA) presented data on the cowpea mosaic virus-vimentin interaction following CPMV in situ vaccination. Her data showed that in situ blocking of vimentin in vivo resulted in enhanced efficacy of CPMV+v9 vs CPMV only.
Session 5 & 6 The focus of both session 5 and 6 were on protein glycovariants.
The session started with Professor Qiang “Shawn” Chen from Arizona State University (USA),
discussing the efficacy of plant-produced monoclonal antibody glycovariants against Chikungunya virus in a mouse model – for both therapeutic and prophylactic use. Interestingly they found that therapeutic potency of mABs depends on its N-glycosylation profile.
This was followed by Melanie Grandits from St George’s University (UK) who discussed the production of a biobetter broadly neutralizing antibody against HIV, 10-1074, in plants. She reported that avoidance of core α1,3-fucosylation enhanced the potential for antibody-dependent cell-mediated toxicity.
In keeping with the theme of improved antibodies, Dr. Audrey Teh from St George’s
University (UK) discussed approaches to improve the effector functions of the broadly neutralizing anti-HIV antibody 3BNC117 by enhancing binding to FcγRIIIa.
The opening session after lunch was delivered by Professor Herta
Steinkellner from the University of Natural Resources and Life Sciences (Austria) on behalf of her PhD student Laura Montero-Morales. The talk described glycoengineering strategies that were necessary for the successful production of IgE in plants. The study used Herceptin as a model antibody and showed that the co-
expression of Leishmania manor LmSTT3D successfully improved the glycan occupancy of the molecule.
Kathrin Goeritzer from the University of Natural Resources and Life Sciences (Austria) continued the discussion about glycoengineering with a presentation on approaches to produce IgA versions of Herceptin in plants. The data set discussed the implications of glycans on structure and binding to host cell receptors.
This was followed by
Catherine Navarre from the Louvaine Institute of Biomolecular Science and Technology (Belgium) who presented on the production of a soluble Cytomegalovirus gB antigen, with 18 predicted N-glycan sites, in tobacco BY2 cells. The glycosylation of the protein was compared to the equivalent protein produced in CHO cells. It is notable that the BY2 cell-derived product was not cleaved.
The final session before lunch was a keynote delivered by Dr. Diego Orzaez from IBMCP-CISC (Spain) about the Newcotiana project. The initiative aims to apply genome engineering approaches to improving Nicotiana benthamiana as a host for protein expression.
ISPMF NEWSLETTER | Issue 16 6
Session 7
Session 7 focused on new technical developments in the field.
The session started with an interesting presentation, by Dr. Emmanuel “Mani” Margolin from the University of Cape
Town (South Africa) about the co-expression of human chaperones in plants to enable the expression of viral fusion glycoproteins as vaccines. He reported that this approach enabled the expression of a number of antigens that could not previously be produced in the system, and that this could be combined with both furin co-expression and glyco-engineering approaches.
This was followed by a report by Dr. Tarlan Mamedov from Akdeniz University (Turkey)
describing enzyme co-expression to address the production of proteins that are not glycosylated in the native host but are aberrantly glycosylated in plants. This is expected to enable the production of authentic prokaryotic proteins, such as described for Plasmodium falciparum antigens. This approach was also reported to improve recognition of malaria antigen by a conformation-specific monoclonal antibody.
The final talk in the session was given by Benjamin Gengenbach from the Fraunhofer Institute for Molecular Biology and Applied
Ecology IME (Germany) who described the use of automated cell packs (AKA robot cookies) to screen transient expression in BY2 cells. The technology was reported to enable the screening of in excess of 2000 samples a day and is offered as a service!
Session 8 The focus of session 8 was virus-like particles.
Dr. Hadrien Peyret from the John Innes Centre (UK), kicked the session off with a talk describing the controlled packaging of RNA
inside cowpea mosaic virus. He reported that by deconstructing the packaging signals, target RNA could be packaged if flanked by 5’ and 3’ UTRs of CPMV RNA 2. This raises the prospect of targeted RNA delivery for immunization or therapeutic treatments.
This was followed by one of the standout talks of the conference, given by Dr. Daniel Ponndorf from the John Innes Centre (UK), who described the expression of Dengue VLPs in plants. Daniel reported the successful co-expression of multiple proteins in plants to promote VLP assembly. He acknowledged that particle stability was a challenge and that the VLPs were not stable in frozen leaves.
In keeping with the theme of
flaviviruses, Professor Qiang
“Shawn” Chen described the use of Hepatitis VLPs displaying flavivirus Envelope Domain III. These were reported to protect mice gainst lethal challenge without the risk of antibody-dependent enhancement of infection for other flaviviruses.
Professor Nicole Steinmetz from the University of California, San Diego (USA) shifted the focus towards the use of Cowpea mosaic virus VLPs for cancer therapies. She described the use of this approach for the treatement of Melanoma, breast, colon and ovarian cancers. She also reported that other VLPs did not induce the equivalent response.
Dr. Aleyo Chabeda, a postdoc from the Biopharming Research Unit (South Africa), concluded the session with a talk about the progress made developing plant-produced HPV pseudovirions. An interesting aspect of the talk is the possibility of using these for the targetted delivery of therapeutic candidates to tumor cells.
Session 9
The 9th and final session of the conference revolved around downstream processing.
The session started with Patrick Opdensteinen from the Fraunhofer Institute for Molecular Biology and Applied Ecology IME (Germany) making a
ISPMF NEWSLETTER | Issue 16 7
convincing argument to use ultrafiltration as part of protein purification strategies from plants. He argued that having additional
molecular weight cut offs for membranes would be helpful.
Lastly, Dr. Illimar Altosaar from Proteins Easy Corporation
(Canada) discussed the prospects of aqueous-free extraction of recombinant proteins.
Special issue of Plants on Plant Molecular Farming
Dr. Rita Abranches will be editing a special of Plants (impact factor 2.632) specifically about Plant Molecular Farming. Submissions are welcome until 30 November 2019 and reduced fees are available.
https://www.mdpi.com/journal/plants/special_issues/plant_molecular_farming
For any enquiries can be adressed directly to Rita at [email protected]
ISPMF NEWSLETTER | Issue 16 8
Upcoming Meetings
Virology Africa 2020
11-14 February 2020 Cape Town, South Africa
Plant, human, animal and bacterial virology contributions welcome
Contact A/Prof. Inga Hitzeroth [email protected]
If you would you like to contribute to the next ISPMF newsletter:
❖ To share your news with the ISPMF community
❖ Write an article or review
❖ Advertise a meeting
❖ Promote your research
We welcome and encourage contributions from all members.
Please email us using the header ‘ISPMF news’
4th ISPMF meeting
will be held in Rome, Italy Monday 8th – Wednesday 10th June 2020
Contact Dr. Eugenio Benvenuto
ISPMF NEWSLETTER | Issue 16 9
This newsletter was put together by:
Jennifer Wayland Emmanuel Margolin
[email protected] [email protected]
www.linkedin.com/in/jennifer-wayland-92540675/ www.linkedin.com/in/emmanuel-margolin-47818a5a/
ISPMF communication officers
Ass. Prof. Inga Hitzeroth Dr. Penny Hundleby [email protected] [email protected]
I am currently a third year PhD student in the
Biopharming Research Unit at the University
of Cape Town, South Africa. My research focus
is on developing a diagnostic reagent as well
as a candidate vaccine for West Nile virus using
Nicotiana benthamiana as the production
platform.
I am a postdoctoral scientist at the University of
Cape Town where I work in the Biopharming
Research Unit and the Viral Vaccine Development
Group. My research is focused on the production
of viral glycoprotein-based vaccines in plants and
their immunogenicity testing in animal models. A
major aspect of this work is the development of
strategies to ensure authentic processing and
maturation along the plant secretory pathway.
Feel free to drop me an email!