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Hasselbeck S, Cheng X. Molecular Marvels: Small Molecules Paving the Way for Enhanced Gene Therapy. Pharmaceuticals (Basel) 2023; 17:41. [PMID: 38256875 PMCID: PMC10818943 DOI: 10.3390/ph17010041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 12/22/2023] [Accepted: 12/25/2023] [Indexed: 01/24/2024] Open
Abstract
In the rapidly evolving landscape of genetic engineering, the advent of CRISPR-Cas technologies has catalyzed a paradigm shift, empowering scientists to manipulate the genetic code with unprecedented accuracy and efficiency. Despite the remarkable capabilities inherent to CRISPR-Cas systems, recent advancements have witnessed the integration of small molecules to augment their functionality, introducing new dimensions to the precision and versatility of gene editing applications. This review delves into the synergy between CRISPR-Cas technologies based specifically on Cas9 and small-molecule drugs, elucidating the pivotal role of chemicals in optimizing target specificity and editing efficiency. By examining a diverse array of applications, ranging from therapeutic interventions to agricultural advancements, we explore how the judicious use of chemicals enhances the precision of CRISPR-Cas9-mediated genetic modifications. In this review, we emphasize the significance of small-molecule drugs in fine-tuning the CRISPR-Cas9 machinery, which allows researchers to exert meticulous control over the editing process. We delve into the mechanisms through which these chemicals bolster target specificity, mitigate off-target effects, and contribute to the overall refinement of gene editing outcomes. Additionally, we discuss the potential of chemical integration in expanding the scope of CRISPR-Cas9 technologies, enabling tailored solutions for diverse genetic manipulation challenges. As CRISPR-Cas9 technologies continue to evolve, the integration of small-molecule drugs emerges as a crucial avenue for advancing the precision and applicability of gene editing techniques. This review not only synthesizes current knowledge but also highlights future prospects, paving the way for a deeper understanding of the synergistic interplay between CRISPR-Cas9 systems and chemical modulators in the pursuit of more controlled and efficient genetic modifications.
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Affiliation(s)
- Sebastian Hasselbeck
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt am Main, 60438 Frankfurt am Main, Germany;
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt am Main, 60438 Frankfurt am Main, Germany
| | - Xinlai Cheng
- Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt am Main, 60438 Frankfurt am Main, Germany;
- Institute of Pharmaceutical Chemistry, Goethe University Frankfurt am Main, 60438 Frankfurt am Main, Germany
- Frankfurt Cancer Institute, 60596 Frankfurt am Main, Germany
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Pessoa JDS, de Oliveira CFM, Mena-Chalco JP, de Carvalho JCM, Ferreira-Camargo LS. Trends on Chlamydomonas reinhardtii growth regimes and bioproducts. Biotechnol Appl Biochem 2023; 70:1830-1842. [PMID: 37337370 DOI: 10.1002/bab.2486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 05/31/2023] [Indexed: 06/21/2023]
Abstract
The green microalga Chlamydomonas reinhardtii is a model microorganism for several areas of study. Among the different microalgae species, it presents advantageous characteristics, such as genomes completely sequenced and well-established techniques for genetic transformation. Despite that, C. reinhardtii production is still not easily commercially viable, especially due to the low biomass yield. So far there are no reports of scientometric study focusing only on C. reinhardtii biomass production process. Considering the need for culture optimization, a scientometric research was conducted to analyze the papers that investigated the growth regimes effects in C. reinhardtii cultivation. The search resulted in 130 papers indexed on Web of Science and Scopus platforms from 1969 to December 2022. The quantitative analysis indicated that the photoautotrophic regime was the most employed in the papers. However, when comparing the three growth regimes, the mixotrophic one led to the highest production of biomass, lipids, and heterologous protein. The production of bioproducts was considered the main objective of most of the papers and, among them, biomass was the most frequently investigated. The highest biomass production reported among the papers was 40 g L-1 in the heterotrophic growth of a transgenic strain. Other culture conditions were also crucial for C. reinhardtii growth, for instance, temperature and cultivation process.
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Ayswaria R, Vijayan J, Nathan VK. Antimicrobial peptides derived from microalgae for combating antibiotic resistance: Current status and prospects. Cell Biochem Funct 2023; 41:142-151. [PMID: 36738178 DOI: 10.1002/cbf.3779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 01/20/2023] [Accepted: 01/21/2023] [Indexed: 02/05/2023]
Abstract
Microalgae are photosynthetic cell factories that produce a spectrum of bioactive compounds extensively used for various applications. Owing to the increase in antibiotic resistance among microbial pathogens, there is a significant thrust for identifying new treatment strategies, and antimicrobial peptides (AMPs) generation is one such method. These AMPs have multiple roles and are active against bacteria, fungi, and viruses. Such peptides synthesized in microalgae have a significant role in medical application, managing aquaculture-associated diseases, and the food industry. To increase their effectiveness and novel peptides, genetically modified microalgae are used as cell factories. With the advancement of new technologies like the CRISPR-Cas system, new avenues are opened for developing novel AMPs using microalgae. This review gives us insight into the various AMPs produced by microalgae and multiple technologies involved in creating such therapeutically essential molecules.
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Affiliation(s)
- Reshma Ayswaria
- Department of Biotechnology, Mercy College, Palakkad, Kerala, India
| | - Jasna Vijayan
- Department of Marine Biology, School of Marine Sciences, Microbiology & Biochemistry, Cochin University of Science and Technology, Cochin, Kerala, India
| | - Vinod Kumar Nathan
- School of Chemical and Biotechnology, SASTRA Deemed to be University, Tirumalaisamudram Thanjavur, Tamilnadu, India
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Garduño-González KA, Peña-Benavides SA, Araújo RG, Castillo-Zacarías C, Melchor-Martínez EM, Oyervides-Muñoz MA, Sosa-Hernández JE, Purton S, Iqbal HM, Parra-Saldívar R. Current challenges for modern vaccines and perspectives for novel treatment alternatives. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2022.103222] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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5
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Ferrer-Miralles N, Saccardo P, Corchero JL, Garcia-Fruitós E. Recombinant Protein Production and Purification of Insoluble Proteins. Methods Mol Biol 2022; 2406:1-31. [PMID: 35089548 DOI: 10.1007/978-1-0716-1859-2_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Proteins are synthesized in heterologous systems because of the impossibility to obtain satisfactory yields from natural sources. The efficient production of soluble and functional recombinant proteins is among the main goals in the biotechnological field. In this context, it is important to point out that under stress conditions, protein folding machinery is saturated and this promotes protein misfolding and, consequently, protein aggregation. Thus, the selection of the optimal expression organism and its growth conditions to minimize the formation of insoluble protein aggregates should be done according to the protein characteristics and downstream requirements. Escherichia coli is the most popular recombinant protein expression system despite the great development achieved so far by eukaryotic expression systems. Besides, other prokaryotic expression systems, such as lactic acid bacteria and psychrophilic bacteria, are gaining interest in this field. However, it is worth mentioning that prokaryotic expression system poses, in many cases, severe restrictions for a successful heterologous protein production. Thus, eukaryotic systems such as mammalian cells, insect cells, yeast, filamentous fungus, and microalgae are an interesting alternative for the production of these difficult-to-express proteins.
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Affiliation(s)
- Neus Ferrer-Miralles
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Cerdanyola del Vallès, Spain
| | - Paolo Saccardo
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Cerdanyola del Vallès, Spain
| | - José Luis Corchero
- Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
- CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Cerdanyola del Vallès, Spain
| | - Elena Garcia-Fruitós
- Department of Ruminant Production, Institut de Recerca i Tecnologia Agroalimentàries (IRTA), Caldes de Montbui, Spain.
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Pirahmadi S, Afzali S, Zargar M, Zakeri S, Mehrizi AA. How can we develop an effective subunit vaccine to achieve successful malaria eradication? Microb Pathog 2021; 160:105203. [PMID: 34547408 DOI: 10.1016/j.micpath.2021.105203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 08/05/2021] [Accepted: 09/17/2021] [Indexed: 12/16/2022]
Abstract
Malaria, a mosquito-borne infection, is the most widespread parasitic disease. Despite numerous efforts to eradicate malaria, this disease is still a health concern worldwide. Owing to insecticide-resistant vectors and drug-resistant parasites, available controlling measures are insufficient to achieve a malaria-free world. Thus, there is an urgent need for new intervention tools such as efficient malaria vaccines. Subunit vaccines are the most promising malaria vaccines under development. However, one of the major drawbacks of subunit vaccines is the lack of efficient and durable immune responses including antigen-specific antibody, CD4+, and CD8+ T-cell responses, long-lived plasma cells, memory cells, and functional antibodies for parasite neutralization or inhibition of parasite invasion. These types of responses could be induced by whole organism vaccines, but eliciting these responses with subunit vaccines has been proven to be more challenging. Consequently, subunit vaccines require several policies to overcome these challenges. In this review, we address common approaches that can improve the efficacy of subunit vaccines against malaria.
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Affiliation(s)
- Sakineh Pirahmadi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
| | - Shima Afzali
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
| | - Mostafa Zargar
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran
| | - Sedigheh Zakeri
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran.
| | - Akram Abouie Mehrizi
- Malaria and Vector Research Group (MVRG), Biotechnology Research Center (BRC), Pasteur Institute of Iran, Tehran, Iran.
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Abstract
Vaccines are biological preparations that improve immunity to particular diseases and form an important innovation of 19th century research. It contains a protein that resembles a disease-causing microorganism and is often made from weak or killed forms of the microbe. Vaccines are agents that stimulate the body’s immune system to recognize the antigen. Now, a new form of vaccine was introduced which will have the power to mask the risk side of conventional vaccines. This type of vaccine was produced from plants which are genetically modified. In the production of edible vaccines, the gene-encoding bacterial or viral disease-causing agent can be incorporated in plants without losing its immunogenic property. The main mechanism of action of edible vaccines is to activate the systemic and mucosal immunity responses against a foreign disease-causing organism. Edible vaccines can be produced by incorporating transgene in to the selected plant cell. At present edible vaccine are developed for veterinary and human use. But the main challenge faced by edible vaccine is its acceptance by the population so that it is necessary to make aware the society about its use and benefits. When compared to other traditional vaccines, edible vaccines are cost effective, efficient and safe. It promises a better prevention option from diseases.
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Affiliation(s)
- Vrinda M Kurup
- Department of Pharmacology, Amrita School of Pharmacy, Amrita Vishwa Vidyapeetham, Amrita Institute of Medical Sciences Healthcare, Education & Research, Kochi, Kerala, 682041, India
| | - Jaya Thomas
- Department of Pharmacology, Amrita School of Pharmacy, Amrita Vishwa Vidyapeetham, Amrita Institute of Medical Sciences Healthcare, Education & Research, Kochi, Kerala, 682041, India.
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Criscuolo E, Caputo V, Diotti RA, Sautto GA, Kirchenbaum GA, Clementi N. Alternative Methods of Vaccine Delivery: An Overview of Edible and Intradermal Vaccines. J Immunol Res 2019; 2019:8303648. [PMID: 30949518 PMCID: PMC6425294 DOI: 10.1155/2019/8303648] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 02/08/2019] [Accepted: 02/14/2019] [Indexed: 01/26/2023] Open
Abstract
Vaccines are recognized worldwide as one of the most important tools for combating infectious diseases. Despite the tremendous value conferred by currently available vaccines toward public health, the implementation of additional vaccine platforms is also of key importance. In fact, currently available vaccines possess shortcomings, such as inefficient triggering of a cell-mediated immune response and the lack of protective mucosal immunity. In this regard, recent work has been focused on vaccine delivery systems, as an alternative to injectable vaccines, to increase antigen stability and improve overall immunogenicity. In particular, novel strategies based on edible or intradermal vaccine formulations have been demonstrated to trigger both a systemic and mucosal immune response. These novel vaccination delivery systems offer several advantages over the injectable preparations including self-administration, reduced cost, stability, and elimination of a cold chain. In this review, the latest findings and accomplishments regarding edible and intradermal vaccines are described in the context of the system used for immunogen expression, their molecular features and capacity to induce a protective systemic and mucosal response.
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Affiliation(s)
- E. Criscuolo
- Microbiology and Virology Unit, “Vita-Salute San Raffaele” University, Milan, Italy
| | - V. Caputo
- Microbiology and Virology Unit, “Vita-Salute San Raffaele” University, Milan, Italy
- Pomona Ricerca S.r.l., Turin, Italy
| | - R. A. Diotti
- Microbiology and Virology Unit, “Vita-Salute San Raffaele” University, Milan, Italy
- Pomona Ricerca S.r.l., Turin, Italy
| | - G. A. Sautto
- Center for Vaccines and Immunology, University of Georgia, Athens, GA, USA
| | | | - N. Clementi
- Microbiology and Virology Unit, “Vita-Salute San Raffaele” University, Milan, Italy
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10
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Abstract
Plant molecular farming depends on a diversity of plant systems for production of useful recombinant proteins. These proteins include protein biopolymers, industrial proteins and enzymes, and therapeutic proteins. Plant production systems include microalgae, cells, hairy roots, moss, and whole plants with both stable and transient expression. Production processes involve a narrowing diversity of bioreactors for cell, hairy root, microalgae, and moss cultivation. For whole plants, both field and automated greenhouse cultivation methods are used with products expressed and produced either in leaves or seeds. Many successful expression systems now exist for a variety of different products with a list of increasingly successful commercialized products. This chapter provides an overview and examples of the current state of plant-based production systems for different types of recombinant proteins.
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Affiliation(s)
| | - Thomas Bley
- Bioprocess Engineering, Institute of Food Technology and Bioprocess Engineering, TU Dresden, Dresden, Germany
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Sierra LS, Dixon CK, Wilken LR. Enzymatic cell disruption of the microalgae Chlamydomonas reinhardtii for lipid and protein extraction. ALGAL RES 2017. [DOI: 10.1016/j.algal.2017.04.004] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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12
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Disease Prevention: An Opportunity to Expand Edible Plant-Based Vaccines? Vaccines (Basel) 2017; 5:vaccines5020014. [PMID: 28556800 PMCID: PMC5492011 DOI: 10.3390/vaccines5020014] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/19/2017] [Accepted: 05/23/2017] [Indexed: 12/17/2022] Open
Abstract
The lethality of infectious diseases has decreased due to the implementation of crucial sanitary procedures such as vaccination. However, the resurgence of pathogenic diseases in different parts of the world has revealed the importance of identifying novel, rapid, and concrete solutions for control and prevention. Edible vaccines pose an interesting alternative that could overcome some of the constraints of traditional vaccines. The term “edible vaccine” refers to the use of edible parts of a plant that has been genetically modified to produce specific components of a particular pathogen to generate protection against a disease. The aim of this review is to present and critically examine “edible vaccines” as an option for global immunization against pathogenic diseases and their outbreaks and to discuss the necessary steps for their production and control and the list of plants that may already be used as edible vaccines. Additionally, this review discusses the required standards and ethical regulations as well as the advantages and disadvantages associated with this powerful biotechnology tool.
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Legastelois I, Buffin S, Peubez I, Mignon C, Sodoyer R, Werle B. Non-conventional expression systems for the production of vaccine proteins and immunotherapeutic molecules. Hum Vaccin Immunother 2016; 13:947-961. [PMID: 27905833 DOI: 10.1080/21645515.2016.1260795] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The increasing demand for recombinant vaccine antigens or immunotherapeutic molecules calls into question the universality of current protein expression systems. Vaccine production can require relatively low amounts of expressed materials, but represents an extremely diverse category consisting of different target antigens with marked structural differences. In contrast, monoclonal antibodies, by definition share key molecular characteristics and require a production system capable of very large outputs, which drives the quest for highly efficient and cost-effective systems. In discussing expression systems, the primary assumption is that a universal production platform for vaccines and immunotherapeutics will unlikely exist. This review provides an overview of the evolution of traditional expression systems, including mammalian cells, yeast and E.coli, but also alternative systems such as other bacteria than E. coli, transgenic animals, insect cells, plants and microalgae, Tetrahymena thermophila, Leishmania tarentolae, filamentous fungi, cell free systems, and the incorporation of non-natural amino acids.
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Affiliation(s)
| | - Sophie Buffin
- a Research and Development, Sanofi Pasteur , Marcy L'Etoile , France
| | - Isabelle Peubez
- a Research and Development, Sanofi Pasteur , Marcy L'Etoile , France
| | | | - Régis Sodoyer
- b Technology Research Institute Bioaster , Lyon , France
| | - Bettina Werle
- b Technology Research Institute Bioaster , Lyon , France
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Cisgenesis and intragenesis in microalgae: promising advancements towards sustainable metabolites production. Appl Microbiol Biotechnol 2016; 100:10225-10235. [DOI: 10.1007/s00253-016-7948-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 10/12/2016] [Accepted: 10/18/2016] [Indexed: 11/26/2022]
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Chen L, Yang X, Luo D, Yu W. Efficient Production of a Bioactive Bevacizumab Monoclonal Antibody Using the 2A Self-cleavage Peptide in Transgenic Rice Callus. FRONTIERS IN PLANT SCIENCE 2016; 7:1156. [PMID: 27555853 PMCID: PMC4977302 DOI: 10.3389/fpls.2016.01156] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 07/19/2016] [Indexed: 05/18/2023]
Abstract
Bevacizumab, a humanized monoclonal antibody (mAb) targeting to the vascular endothelial growth factor (VEGF), has been widely used in clinical practice for the treatment of multiple cancers. Bevacizumab was mostly produced by the mammalian cell expression system. We here reported the first plant-derived Bevacizumab by using transgenic rice callus as an alternative gene expression system. Codon-optimized Bevacizumab light chain (BLC) and Bevacizumab heavy chain (BHC) genes were designed, synthesized as a polyprotein with a 2A self-cleavage linker peptide from the Foot-and-mouth disease virus, cloned into a plant binary vector under a constitutive maize ubiquitin promoter, and transformed into rice nuclear genome through Agrobacterium-mediated transformation. Southern blot and western blot analyses confirmed the integration and expression of BLC and BHC genes in transgenic rice callus. Enzyme-linked immunosorbent assay (ELISA) analysis indicated that the rice-derived Bevacizumab mAb was biologically active and the recombinant mAb was expressed at high levels (160.7-242.8 mg/Kg) in transgenic rice callus. The mAb was purified by using protein A affinity chromatography and the purified antibody was tested for its binding affinity with its target human VEGF (hVEGF) antigen by ELISA. Rice callus produced Bevacizumab and a commercial Bevacizumab (Avastin) were shown to have similar binding affinity to hVEGF. These results indicated that rice callus produced Bevacizumab could have similar biological activity and might potentially be used as a cost-effective biosimilar molecule in future cancer treatment.
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Affiliation(s)
- Lei Chen
- School of Life Sciences, Sun Yat-sen UniversityGuangzhou, China
- Shenzhen Research Institute, The Chinese University of Hong KongShenzhen, China
| | - Xiaoyu Yang
- College of Life Sciences, Shenzhen UniversityShenzhen, China
| | - Da Luo
- School of Life Sciences, Sun Yat-sen UniversityGuangzhou, China
| | - Weichang Yu
- College of Life Sciences, Shenzhen UniversityShenzhen, China
- *Correspondence: Weichang Yu,
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Makhzoum A, Benyammi R, Moustafa K, Trémouillaux-Guiller J. Recent advances on host plants and expression cassettes' structure and function in plant molecular pharming. BioDrugs 2015; 28:145-59. [PMID: 23959796 PMCID: PMC7100180 DOI: 10.1007/s40259-013-0062-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Plant molecular pharming is a promising system to produce important recombinant proteins such as therapeutic antibodies, pharmaceuticals, enzymes, growth factors, and vaccines. The system provides an interesting alternative method to the direct extraction of proteins from inappropriate source material while offering the possibility to overcome problems related to product safety and source availability. Multiple factors including plant hosts, genes of interest, expression vector cassettes, and extraction and purification techniques play important roles in the plant molecular pharming. Plant species, as a biosynthesis platform, are a crucial factor in achieving high yields of recombinant protein in plant. The choice of recombinant gene and its expression strategy is also of great importance in ensuring a high amount of the recombinant proteins. Many studies have been conducted to improve expression, accumulation, and purification of the recombinant protein from molecular pharming systems. Re-engineered vectors and expression cassettes are also pivotal tools in enhancing gene expression at the transcription and translation level, and increasing protein accumulation, stability, retention and targeting of specific organelles. In this review, we report recent advances and strategies of plant molecular pharming while focusing on the choice of plant hosts and the role of some molecular pharming elements and approaches: promoters, codon optimization, signal sequences, and peptides used for upstream design, purification and downstream processing.
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Affiliation(s)
- Abdullah Makhzoum
- Department of Biology, The University of Western Ontario, London, ON N6A 5B7 Canada
| | - Roukia Benyammi
- Laboratory of Genetic Resources and Biotechnology of the National Superior School of Agronomy, Algiers, Algeria
| | - Khaled Moustafa
- Institut Mondor de la Recherche Biomédicale, Hôpital Henri-Mondor, Créteil, France
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18
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Ferrer-Miralles N, Saccardo P, Corchero JL, Xu Z, García-Fruitós E. General introduction: recombinant protein production and purification of insoluble proteins. Methods Mol Biol 2015; 1258:1-24. [PMID: 25447856 DOI: 10.1007/978-1-4939-2205-5_1] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Proteins are synthesized in heterologous systems because of the impossibility to obtain satisfactory yields from natural sources. The production of soluble and functional recombinant proteins is among the main goals in the biotechnological field. In this context, it is important to point out that under stress conditions, protein folding machinery is saturated and this promotes protein misfolding and, consequently, protein aggregation. Thus, the selection of the optimal expression organism and the most appropriate growth conditions to minimize the formation of insoluble proteins should be done according to the protein characteristics and downstream requirements. Escherichia coli is the most popular recombinant protein expression system despite the great development achieved so far by eukaryotic expression systems. Besides, other prokaryotic expression systems, such as lactic acid bacteria and psychrophilic bacteria, are gaining interest in this field. However, it is worth mentioning that prokaryotic expression system poses, in many cases, severe restrictions for a successful heterologous protein production. Thus, eukaryotic systems such as mammalian cells, insect cells, yeast, filamentous fungus, and microalgae are an interesting alternative for the production of these difficult-to-express proteins.
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Affiliation(s)
- Neus Ferrer-Miralles
- Departament de Genètica i de Microbiologia, Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona, Bellaterra, Cerdanyola del Vallès, 08193, Barcelona, Spain
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The potential of transgenic green microalgae; a robust photobioreactor to produce recombinant therapeutic proteins. World J Microbiol Biotechnol 2014; 30:2783-96. [PMID: 25115849 DOI: 10.1007/s11274-014-1714-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2013] [Accepted: 07/30/2014] [Indexed: 02/01/2023]
Abstract
Microalgae have been used in food, cosmetic, and biofuel industries as a natural source of lipids, vitamins, pigments and antioxidants for a long time. Green microalgae, as potent photobioreactors, can be considered as an economical expression system to produce recombinant therapeutical proteins at large-scale due to low cost of production and scaling-up capitalization owning to the inexpensive medium requirement, fast growth rate, and the ease of manipulation. These microalgae possess all benefit eukaryotic expression systems including the ability of post-translational modifications required for proper folding and stability of active proteins. Among the many items regarded as recombinant protein production, this review compares the different expression systems with green microalgae like Dunaliella by viewing the nuclear/chloroplast transformation challenges/benefits, related selection markers/reporter genes, and crucial factors/strategies affecting the increase of foreign protein expression in microalgae transformants. Some important factors were discussed regarding the increase of protein yielding in microalgae transformants including: transformation-associated genotypic modifications, endogenous regulatory factors, promoters, codon optimization, enhancer elements, and milking of recombinant protein.
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Yemets AI, Tanasienko IV, Krasylenko YA, Blume YB. Plant-based biopharming of recombinant human lactoferrin. Cell Biol Int 2014; 38:989-1002. [PMID: 24803187 DOI: 10.1002/cbin.10304] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Accepted: 03/31/2014] [Indexed: 11/08/2022]
Abstract
Recombinant proteins are currently recognized as pharmaceuticals, enzymes, food constituents, nutritional additives, antibodies and other valuable products for industry, healthcare, research, and everyday life. Lactoferrin (Lf), one of the promising human milk proteins, occupies the expanding biotechnological food market niche due to its important versatile properties. Lf shows antiviral, antimicrobial, antiprotozoal and antioxidant activities, modulates cell growth rate, binds glycosaminoglycans and lipopolysaccharides, and also inputs into the innate/specific immune responses. Development of highly efficient human recombinant Lf expression systems employing yeasts, filamentous fungi and undoubtedly higher plants as bioreactors for the large-scale Lf production is a biotechnological challenge. This review highlights the advantages and disadvantages of the existing non-animal Lf expression systems from the standpoint of protein yield and its biological activity. Special emphasis is put on the benefits of monocot plant system for Lf expression and the biosafety aspects of the transgenic Lf-expressing plants.
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Affiliation(s)
- Alla I Yemets
- Department of Genomics and Molecular Biotechnology, Institute of Food Biotechnology and Genomics, National Academy of Sciences of Ukraine, Osipovskogo Str., 2a, Kyiv, 04123, Ukraine
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21
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Rosales-Mendoza S. Future directions for the development of Chlamydomonas-based vaccines. Expert Rev Vaccines 2014; 12:1011-9. [PMID: 24053395 DOI: 10.1586/14760584.2013.825455] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Besides serving as a valuable model in biological sciences, Chamydomonas reinhardtii has been used during the last decade in the biotechnology arena to establish models for the low cost production of vaccines. Antigens from various pathogens including Plasmodium falciparum, foot and mouth disease virus, Staphylococcus aureus, classical swine fever virus (CSFV) as well as some auto-antigens, have been produced in C. reinhardtii. Although some of them have been functionally characterized with promising results, this review identifies future directions for the advancement in the exploitation of this robust and safe vaccine production platform. The present analysis reflects that important immunological implications exist for this system and remain unexplored, including the possible adjuvant effects of algae biomolecules, the effect of bioencapsulation on immunogenicity and the possible development of whole-cell vaccines as an approach to trigger cytotoxic immune responses. Recently described molecular strategies that aim to optimize the expression of nuclear-encoded target antigens are also discussed.
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Affiliation(s)
- Sergio Rosales-Mendoza
- Laboratorio de Biofarmacéuticos Recombinantes, Facultad de Ciencias Químicas, Universidad Autónoma de San Luis Potosí, Av. Dr. Manuel Nava 6, SLP, 78210, México +52 444 826 2440 +52 444 826 2440
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22
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Specht EA, Mayfield SP. Algae-based oral recombinant vaccines. Front Microbiol 2014; 5:60. [PMID: 24596570 PMCID: PMC3925837 DOI: 10.3389/fmicb.2014.00060] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Accepted: 01/30/2014] [Indexed: 11/25/2022] Open
Abstract
Recombinant subunit vaccines are some of the safest and most effective vaccines available, but their high cost and the requirement of advanced medical infrastructure for administration make them impractical for many developing world diseases. Plant-based vaccines have shifted that paradigm by paving the way for recombinant vaccine production at agricultural scale using an edible host. However, enthusiasm for “molecular pharming” in food crops has waned in the last decade due to difficulty in developing transgenic crop plants and concerns of contaminating the food supply. Microalgae could be poised to become the next candidate in recombinant subunit vaccine production, as they present several advantages over terrestrial crop plant-based platforms including scalable and contained growth, rapid transformation, easily obtained stable cell lines, and consistent transgene expression levels. Algae have been shown to accumulate and properly fold several vaccine antigens, and efforts are underway to create recombinant algal fusion proteins that can enhance antigenicity for effective orally delivered vaccines. These approaches have the potential to revolutionize the way subunit vaccines are made and delivered – from costly parenteral administration of purified protein, to an inexpensive oral algae tablet with effective mucosal and systemic immune reactivity.
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Affiliation(s)
- Elizabeth A Specht
- California Center for Algae Biotechnology, University of California at San Diego La Jolla, CA, USA
| | - Stephen P Mayfield
- California Center for Algae Biotechnology, University of California at San Diego La Jolla, CA, USA
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23
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Ice recrystallization inhibition mediated by a nuclear-expressed and -secreted recombinant ice-binding protein in the microalga Chlamydomonas reinhardtii. Appl Microbiol Biotechnol 2013; 97:9763-72. [PMID: 24037309 DOI: 10.1007/s00253-013-5226-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2013] [Revised: 08/26/2013] [Accepted: 08/28/2013] [Indexed: 01/08/2023]
Abstract
A Lolium perenne ice-binding protein (LpIBP) demonstrates superior ice recrystallization inhibition (IRI) activity and has proposed applications in cryopreservation, food texturing, as well as in being a "green" gas hydrate inhibitor. Recombinant production of LpIBP has been previously conducted in bacterial and yeast systems for studies of protein characterization, but large-scale applications have been hitherto limited due to high production costs. In this work, a codon-optimized LpIBP was recombinantly expressed and secreted in a novel one-step vector system from the nuclear genome of the green microalga Chlamydomonas reinhardtii. Both mixotrophic and photoautotrophic growth regimes supported LpIBP expression, indicating the feasibility of low-cost production using minimal medium, carbon dioxide, and light energy as input. In addition, multiple growth and bioproduct extraction cycles were performed by repetitive batch cultivation trials, demonstrating the potential for semi-continuous production and biomass harvesting. Concentrations of recombinant protein reached in this proof of concept approach were sufficient to demonstrate IRI activity in culture media without additional purification or concentration, with activity further verified by thermal hysteresis and morphology assays. The incorporation of the recombinant LpIBP into a model gas hydrate offers the promise that algal production may eventually find application as a "green" hydrate inhibitor.
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Koskimaki JE, Blazier AS, Clarens AF, Papin JA. Computational Models of Algae Metabolism for Industrial Applications. Ind Biotechnol (New Rochelle N Y) 2013. [DOI: 10.1089/ind.2013.0012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Jacob E. Koskimaki
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA
| | - Anna S. Blazier
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA
| | - Andres F. Clarens
- Department of Civil and Environmental Engineering, University of Virginia, Charlottesville, VA
| | - Jason A. Papin
- Department of Biomedical Engineering, University of Virginia, Charlottesville, VA
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25
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Díaz-Santos E, de la Vega M, Vila M, Vigara J, León R. Efficiency of different heterologous promoters in the unicellular microalgaChlamydomonas reinhardtii. Biotechnol Prog 2013; 29:319-28. [DOI: 10.1002/btpr.1690] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 12/27/2012] [Indexed: 01/27/2023]
Affiliation(s)
- Encarnación Díaz-Santos
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
| | - Marta de la Vega
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
| | - Marta Vila
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
| | - Javier Vigara
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
| | - Rosa León
- Lab Bioquímica y Biología Molecular. Departamento de Química y Ciencia de Materiales, Facultad de Ciencias Experimentales; Universidad de Huelva; Avda. Fuerzas Armadas s/n 21007 Huelva Spain
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26
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Corchero JL, Gasser B, Resina D, Smith W, Parrilli E, Vázquez F, Abasolo I, Giuliani M, Jäntti J, Ferrer P, Saloheimo M, Mattanovich D, Schwartz S, Tutino ML, Villaverde A. Unconventional microbial systems for the cost-efficient production of high-quality protein therapeutics. Biotechnol Adv 2012; 31:140-53. [PMID: 22985698 DOI: 10.1016/j.biotechadv.2012.09.001] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2011] [Revised: 09/04/2012] [Accepted: 09/07/2012] [Indexed: 12/18/2022]
Abstract
Both conventional and innovative biomedical approaches require cost-effective protein drugs with high therapeutic potency, improved bioavailability, biocompatibility, stability and pharmacokinetics. The growing longevity of the human population, the increasing incidence and prevalence of age-related diseases and the better comprehension of genetic-linked disorders prompt to develop natural and engineered drugs addressed to fulfill emerging therapeutic demands. Conventional microbial systems have been for long time exploited to produce biotherapeutics, competing with animal cells due to easier operation and lower process costs. However, both biological platforms exhibit important drawbacks (mainly associated to intracellular retention of the product, lack of post-translational modifications and conformational stresses), that cannot be overcome through further strain optimization merely due to physiological constraints. The metabolic diversity among microorganisms offers a spectrum of unconventional hosts, that, being able to bypass some of these weaknesses, are under progressive incorporation into production pipelines. In this review we describe the main biological traits and potentials of emerging bacterial, yeast, fungal and microalgae systems, by comparing selected leading species with well established conventional organisms with a long run in protein drug production.
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27
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Green factory: Plants as bioproduction platforms for recombinant proteins. Biotechnol Adv 2012; 30:1171-84. [DOI: 10.1016/j.biotechadv.2011.08.020] [Citation(s) in RCA: 132] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 08/24/2011] [Accepted: 08/30/2011] [Indexed: 12/15/2022]
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28
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Qin S, Lin H, Jiang P. Advances in genetic engineering of marine algae. Biotechnol Adv 2012; 30:1602-13. [PMID: 22634258 DOI: 10.1016/j.biotechadv.2012.05.004] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 05/12/2012] [Accepted: 05/18/2012] [Indexed: 12/28/2022]
Abstract
Algae are a component of bait sources for animal aquaculture, and they produce abundant valuable compounds for the chemical industry and human health. With today's fast growing demand for algae biofuels and the profitable market for cosmetics and pharmaceuticals made from algal natural products, the genetic engineering of marine algae has been attracting increasing attention as a crucial systemic technology to address the challenge of the biomass feedstock supply for sustainable industrial applications and to modify the metabolic pathway for the more efficient production of high-value products. Nevertheless, to date, only a few marine algae species can be genetically manipulated. In this article, an updated account of the research progress in marine algal genomics is presented along with methods for transformation. In addition, vector construction and gene selection strategies are reviewed. Meanwhile, a review on the progress of bioreactor technologies for marine algae culture is also revisited.
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Affiliation(s)
- Song Qin
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, Shandong, China.
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29
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Rosales-Mendoza S, Paz-Maldonado LMT, Soria-Guerra RE. Chlamydomonas reinhardtii as a viable platform for the production of recombinant proteins: current status and perspectives. PLANT CELL REPORTS 2012; 31:479-94. [PMID: 22080228 DOI: 10.1007/s00299-011-1186-8] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Revised: 10/31/2011] [Accepted: 11/01/2011] [Indexed: 05/03/2023]
Abstract
Chlamydomonas reinhardtii has many advantages compared with traditional systems for the molecular farming of recombinant proteins. These include low production costs, rapid scalability at pilot level, absence of human pathogens and the ability to fold and assemble complex proteins accurately. Currently, the successful expression of several proteins with pharmaceutical relevance has been reported from the nuclear and the chloroplastic genome of this alga, demonstrating its usefulness for biotechnological applications. However, several factors affect the level of recombinant protein expression in Chlamydomonas such as enhancer elements, codon dependency, sensitivity to proteases and transformation-associated genotypic modification. The present review outlines a number of strategies to increase protein yields and summarizes recent achievements in algal protein production including biopharmaceuticals such as vaccines, antibodies, hormones and enzymes with implications on health-related approaches. The current status of bioreactor developments for algal culture and the challenges of scale-up and optimization processes are also discussed.
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Affiliation(s)
- Sergio Rosales-Mendoza
- Laboratorio de Biofarmacéuticos Recombinantes, Universidad Autónoma de San Luis Potosí, Av. Dr. Manuel Nava 6, 78210 San Luis Potosí, SLP, Mexico.
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30
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Strategies for high-level recombinant protein expression in transgenic microalgae: A review. Biotechnol Adv 2010; 28:910-8. [DOI: 10.1016/j.biotechadv.2010.08.006] [Citation(s) in RCA: 127] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2010] [Revised: 08/03/2010] [Accepted: 08/13/2010] [Indexed: 11/22/2022]
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31
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Specht E, Miyake-Stoner S, Mayfield S. Micro-algae come of age as a platform for recombinant protein production. Biotechnol Lett 2010; 32:1373-83. [PMID: 20556634 PMCID: PMC2941057 DOI: 10.1007/s10529-010-0326-5] [Citation(s) in RCA: 212] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Accepted: 06/07/2010] [Indexed: 12/03/2022]
Abstract
A complete set of genetic tools is still being developed for the micro-alga Chlamydomonas reinhardtii. Yet even with this incomplete set, this photosynthetic single-celled plant has demonstrated significant promise as a platform for recombinant protein expression. In recent years, techniques have been developed that allow for robust expression of genes from both the nuclear and plastid genome. With these advances, many research groups have examined the pliability of this and other micro-algae as biological machines capable of producing recombinant peptides and proteins. This review describes recent successes in recombinant protein production in Chlamydomonas, including production of complex mammalian therapeutic proteins and monoclonal antibodies at levels sufficient for production at economic parity with existing production platforms. These advances have also shed light on the details of algal protein production at the molecular level, and provide insight into the next steps for optimizing micro-algae as a useful platform for the production of therapeutic and industrially relevant recombinant proteins.
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Affiliation(s)
- Elizabeth Specht
- San Diego Center for Algae Biotechnology, Department of Biological Sciences, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0368 USA
| | - Shigeki Miyake-Stoner
- San Diego Center for Algae Biotechnology, Department of Biological Sciences, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0368 USA
| | - Stephen Mayfield
- San Diego Center for Algae Biotechnology, Department of Biological Sciences, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0368 USA
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32
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Specht E, Miyake-Stoner S, Mayfield S. Micro-algae come of age as a platform for recombinant protein production. Biotechnol Lett 2010; 32:1373-1383. [PMID: 20556634 DOI: 10.1007/s10529-010-0326-325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Accepted: 06/07/2010] [Indexed: 05/28/2023]
Abstract
A complete set of genetic tools is still being developed for the micro-alga Chlamydomonas reinhardtii. Yet even with this incomplete set, this photosynthetic single-celled plant has demonstrated significant promise as a platform for recombinant protein expression. In recent years, techniques have been developed that allow for robust expression of genes from both the nuclear and plastid genome. With these advances, many research groups have examined the pliability of this and other micro-algae as biological machines capable of producing recombinant peptides and proteins. This review describes recent successes in recombinant protein production in Chlamydomonas, including production of complex mammalian therapeutic proteins and monoclonal antibodies at levels sufficient for production at economic parity with existing production platforms. These advances have also shed light on the details of algal protein production at the molecular level, and provide insight into the next steps for optimizing micro-algae as a useful platform for the production of therapeutic and industrially relevant recombinant proteins.
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Affiliation(s)
- Elizabeth Specht
- San Diego Center for Algae Biotechnology, Department of Biological Sciences, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093-0368, USA
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33
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Rasala BA, Muto M, Lee PA, Jager M, Cardoso RMF, Behnke CA, Kirk P, Hokanson CA, Crea R, Mendez M, Mayfield SP. Production of therapeutic proteins in algae, analysis of expression of seven human proteins in the chloroplast of Chlamydomonas reinhardtii. PLANT BIOTECHNOLOGY JOURNAL 2010; 8:719-33. [PMID: 20230484 PMCID: PMC2918638 DOI: 10.1111/j.1467-7652.2010.00503.x] [Citation(s) in RCA: 159] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Recombinant proteins are widely used today in many industries, including the biopharmaceutical industry, and can be expressed in bacteria, yeasts, mammalian and insect cell cultures, or in transgenic plants and animals. In addition, transgenic algae have also been shown to support recombinant protein expression, both from the nuclear and chloroplast genomes. However, to date, there are only a few reports on recombinant proteins expressed in the algal chloroplast. It is unclear whether this is because of few attempts or of limitations of the system that preclude expression of many proteins. Thus, we sought to assess the versatility of transgenic algae as a recombinant protein production platform. To do this, we tested whether the algal chloroplast could support the expression of a diverse set of current or potential human therapeutic proteins. Of the seven proteins chosen, >50% expressed at levels sufficient for commercial production. Three expressed at 2%-3% of total soluble protein, while a forth protein accumulated to similar levels when translationally fused to a well-expressed serum amyloid protein. All of the algal chloroplast-expressed proteins are soluble and showed biological activity comparable to that of the same proteins expressed using traditional production platforms. Thus, the success rate, expression levels, and bioactivity achieved demonstrate the utility of Chlamydomonas reinhardtii as a robust platform for human therapeutic protein production.
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Affiliation(s)
- Beth A Rasala
- Department of Cell Biology and the Skaggs Institute for Chemical Biology, 10550 N. Torrey Pines Rd, La Jolla, CA92037, USA
| | - Machiko Muto
- Department of Cell Biology and the Skaggs Institute for Chemical Biology, 10550 N. Torrey Pines Rd, La Jolla, CA92037, USA
| | - Philip A Lee
- Department of Cell Biology and the Skaggs Institute for Chemical Biology, 10550 N. Torrey Pines Rd, La Jolla, CA92037, USA
| | - Michal Jager
- Department of Cell Biology and the Skaggs Institute for Chemical Biology, 10550 N. Torrey Pines Rd, La Jolla, CA92037, USA
| | | | - Craig A Behnke
- Sapphire Energy, 3115 Merryfield Rd., San Diego, CA 92121
| | - Peter Kirk
- Protelica, 26118 Research Pl, Hayward, CA 94545
| | | | | | - Michael Mendez
- Sapphire Energy, 3115 Merryfield Rd., San Diego, CA 92121
| | - Stephen P Mayfield
- Department of Cell Biology and the Skaggs Institute for Chemical Biology, 10550 N. Torrey Pines Rd, La Jolla, CA92037, USA
- Corresponding author: SPM:
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34
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De Muynck B, Navarre C, Boutry M. Production of antibodies in plants: status after twenty years. PLANT BIOTECHNOLOGY JOURNAL 2010; 8:529-63. [PMID: 20132515 DOI: 10.1111/j.1467-7652.2009.00494.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Thanks to their potential to bind virtually all types of molecules; monoclonal antibodies are in increasing demand as therapeutics and diagnostics. To overcome the overloading of current production facilities, alternative expression systems have been developed, of which plants appear the most promising. In this review, we focus on the expression of monoclonal IgG or IgM in plant species. We analyse the data for 32 different antibodies expressed in various ways, differing in DNA construction, transformation method, signal peptide source, presence or absence of an endoplasmic reticulum retention sequence, host species and the organs tested, together resulting in 98 reported combinations. A large heterogeneity is found in the quantity and quality of the antibody produced. We discuss in more detail the strategy used to express both chains, the nature of the transcription promoters, subcellular localization and unintended proteolysis, when encountered.
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Affiliation(s)
- Benoit De Muynck
- Institut des Sciences de la Vie, Université catholique de Louvain, Louvain-la-Neuve, Belgium
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35
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Tran M, Zhou B, Pettersson PL, Gonzalez MJ, Mayfield SP. Synthesis and assembly of a full-length human monoclonal antibody in algal chloroplasts. Biotechnol Bioeng 2009; 104:663-73. [PMID: 19562731 DOI: 10.1002/bit.22446] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Monoclonal antibodies can be effective therapeutics against a variety of human diseases, but currently marketed antibody-based drugs are very expensive compared to other therapeutic options. Here, we show that the eukaryotic green algae Chlamydomonas reinhardtii is capable of synthesizing and assembling a full-length IgG1 human monoclonal antibody (mAb) in transgenic chloroplasts. This antibody, 83K7C, is derived from a human IgG1 directed against anthrax protective antigen 83 (PA83), and has been shown to block the effects of anthrax toxin in animal models. Here we show that 83K7C heavy and light chain proteins expressed in the chloroplast accumulate as soluble proteins that assemble into complexes containing two heavy and two light chain proteins. The algal-expressed 83K7C binds PA83 in vitro with similar affinity to the mammalian-expressed 83K7C antibody. In addition, a second human IgG1 and a mouse IgG1 were also expressed and shown to properly assemble in algal chloroplast. These results show that chloroplasts have the ability to fold and assemble full-length human mAbs, and suggest the potential of algae as a platform for the cost effective production of complex human therapeutic proteins.
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Affiliation(s)
- Miller Tran
- Department of Cell Biology, The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, California 92037, USA
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36
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Sharma AK, Sharma MK. Plants as bioreactors: Recent developments and emerging opportunities. Biotechnol Adv 2009; 27:811-832. [PMID: 19576278 PMCID: PMC7125752 DOI: 10.1016/j.biotechadv.2009.06.004] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2009] [Revised: 06/15/2009] [Accepted: 06/16/2009] [Indexed: 12/18/2022]
Abstract
In recent years, the use of plants as bioreactors has emerged as an exciting area of research and significant advances have created new opportunities. The driving forces behind the rapid growth of plant bioreactors include low production cost, product safety and easy scale up. As the yield and concentration of a product is crucial for commercial viability, several strategies have been developed to boost up protein expression in transgenic plants. Augmenting tissue-specific transcription, elevating transcript stability, tissue-specific targeting, translation optimization and sub-cellular accumulation are some of the strategies employed. Various kinds of products that are currently being produced in plants include vaccine antigens, medical diagnostics proteins, industrial and pharmaceutical proteins, nutritional supplements like minerals, vitamins, carbohydrates and biopolymers. A large number of plant-derived recombinant proteins have reached advanced clinical trials. A few of these products have already been introduced in the market.
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Affiliation(s)
- Arun K Sharma
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi 110021, India.
| | - Manoj K Sharma
- Department of Plant Molecular Biology, University of Delhi South Campus, New Delhi 110021, India
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37
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Muto M, Henry RE, Mayfield SP. Accumulation and processing of a recombinant protein designed as a cleavable fusion to the endogenous Rubisco LSU protein in Chlamydomonas chloroplast. BMC Biotechnol 2009; 9:26. [PMID: 19323825 PMCID: PMC2671499 DOI: 10.1186/1472-6750-9-26] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2008] [Accepted: 03/26/2009] [Indexed: 12/04/2022] Open
Abstract
Background Expression of recombinant proteins in green algal chloroplast holds substantial promise as a platform for the production of human therapeutic proteins. A number of proteins have been expressed in the chloroplast of Chlamydomonas reinhardtii, including complex mammalian proteins, but many of these proteins accumulate to significantly lower levels than do endogenous chloroplast proteins. We examined if recombinant protein accumulation could be enhanced by genetically fusing the recombinant reporter protein, luciferase, to the carboxy-terminal end of an abundant endogenous protein, the large subunit of ribulose bisphosphate carboxylase (Rubisco LSU). Additionally, as recombinant proteins fused to endogenous proteins are of little clinical or commercial value, we explored the possibility of engineering our recombinant protein to be cleavable from the endogenous protein in vivo. This strategy would obviate the need for further in vitro processing steps in order to produce the desired recombinant protein. To achieve this, a native protein-processing site from preferredoxin (preFd) was placed between the Rubisco LSU and luciferase coding regions in the fusion protein construct. Results The luciferase from the fusion protein accumulated to significantly higher levels than luciferase expressed alone. By eliminating the endogenous Rubisco large subunit gene (rbcL), we achieved a further increase in luciferase accumulation with respect to luciferase expression in the WT background. Importantly, near-wild type levels of functional Rubisco holoenzyme were generated following the proteolytic removal of the fused luciferase, while luciferase activity for the fusion protein was almost ~33 times greater than luciferase expressed alone. These data demonstrate the utility of using fusion proteins to enhance recombinant protein accumulation in algal chloroplasts, and also show that engineered proteolytic processing sites can be used to liberate the exogenous protein from the endogenous fusion partner, allowing for the purification of the intended mature protein. Conclusion These results demonstrate the utility of fusion proteins in algal chloroplast as a method to increase accumulation of recombinant proteins that are difficult to express. Since Rubisco is ubiquitous to land plants and green algae, this strategy may also be applied to higher plant transgenic expression systems.
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Affiliation(s)
- Machiko Muto
- The Department of Cell Biology and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 N. Pines Rd. La Jolla, CA 92037, USA.
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38
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Eichler-Stahlberg A, Weisheit W, Ruecker O, Heitzer M. Strategies to facilitate transgene expression in Chlamydomonas reinhardtii. PLANTA 2009; 229:873-83. [PMID: 19127370 DOI: 10.1007/s00425-008-0879-x] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2008] [Accepted: 12/17/2008] [Indexed: 05/20/2023]
Abstract
The unicellular green alga Chlamydomonas reinhardtii has been identified as a promising organism for the production of recombinant proteins. While during the last years important improvements have been developed for the production of proteins within the chloroplast, the expression levels of transgenes from the nuclear genome were too low to be of biotechnological importance. In this study, we integrated endogenous intronic sequences into the expression cassette to enhance the expression of transgenes in the nucleus. The insertion of one or more copies of intron sequences from the Chlamydomonas RBCS2 gene resulted in increased expression levels of a Renilla-luciferase gene used as a reporter. Although any of the three RBCS2 introns alone had a positive effect on expression, their integration in their physiological number and order created an over-proportional stimulating effect observed in all transformants. The secretion of the luciferase protein into the medium was achieved by using the export sequence of the Chlamydomonas ARS2 gene in a cell wall deficient strain and Renilla-luciferase could be successfully concentrated with the help of attached C-terminal protein tags. Similarly, a codon adapted gene variant for human erythropoietin (crEpo) was expressed as a protein of commercial relevance. Extracellular erythropoietin produced in Chlamydomonas showed a molecular mass of 33 kDa probably resulting from post-translational modifications. Both, the increased expression levels of transgenes by integration of introns and the isolation of recombinant proteins from the culture medium are important steps towards an extended biotechnological use of this alga.
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Affiliation(s)
- Alke Eichler-Stahlberg
- Center of Excellence for Fluorescent Bioanalysis, University of Regensburg, Josef-Engert-Str. 9, 93053, Regensburg, Germany
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Tools and techniques for chloroplast transformation of Chlamydomonas. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 616:34-45. [PMID: 18161489 DOI: 10.1007/978-0-387-75532-8_4] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The chloroplast organelle of plant and algal cells contains its own genetic system with a genome of a hundred or so genes. Stable transformation of the chloroplast was first achieved in 1988, using the newly developed biolistic method of DNA delivery to introduce cloned DNA into the genome of the green unicellular alga Chlamydomonas reinhardtii. Since that time there have been significant developments in chloroplast genetic engineering using this versatile organism, and it is probable that the next few years will see increasing interest in commercial applications whereby high-value therapeutic proteins and other recombinant products are synthesized in the Chlamydomonas chloroplast. In this chapter I review the basic methodology of chloroplast transformation, the current techniques and applications, and the future possibilities for using the Chlamydomonas chloroplast as a green organelle factory.
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Wang X, Brandsma M, Tremblay R, Maxwell D, Jevnikar AM, Huner N, Ma S. A novel expression platform for the production of diabetes-associated autoantigen human glutamic acid decarboxylase (hGAD65). BMC Biotechnol 2008; 8:87. [PMID: 19014643 PMCID: PMC2621204 DOI: 10.1186/1472-6750-8-87] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2008] [Accepted: 11/17/2008] [Indexed: 11/26/2022] Open
Abstract
Background Human glutamic acid decarboxylase 65 (hGAD65) is a key autoantigen in type 1 diabetes, having much potential as an important marker for the prediction and diagnosis of type 1 diabetes, and for the development of novel antigen-specific therapies for the treatment of type 1 diabetes. However, recombinant production of hGAD65 using conventional bacterial or mammalian cell culture-based expression systems or nuclear transformed plants is limited by low yield and low efficiency. Chloroplast transformation of the unicellular eukaryotic alga Chlamydomonas reinhardtii may offer a potential solution. Results A DNA cassette encoding full-length hGAD65, under the control of the C. reinhardtii chloroplast rbcL promoter and 5'- and 3'-UTRs, was constructed and introduced into the chloroplast genome of C. reinhardtii by particle bombardment. Integration of hGAD65 DNA into the algal chloroplast genome was confirmed by PCR. Transcriptional expression of hGAD65 was demonstrated by RT-PCR. Immunoblotting verified the expression and accumulation of the recombinant protein. The antigenicity of algal-derived hGAD65 was demonstrated with its immunoreactivity to diabetic sera by ELISA and by its ability to induce proliferation of spleen cells from NOD mice. Recombinant hGAD65 accumulated in transgenic algae, accounts for approximately 0.25–0.3% of its total soluble protein. Conclusion Our results demonstrate the potential value of C. reinhardtii chloroplasts as a novel platform for rapid mass production of immunologically active hGAD65. This demonstration opens the future possibility for using algal chloroplasts as novel bioreactors for the production of many other biologically active mammalian therapeutic proteins.
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Affiliation(s)
- Xiaofeng Wang
- Department of Biology, University of Western Ontario, London, Ontario, N6A 5B7, Canada.
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Cadoret JP, Bardor M, Lerouge P, Cabigliera M, Henriquez V, Carlier A. Les microalgues. Med Sci (Paris) 2008; 24:375-82. [DOI: 10.1051/medsci/2008244375] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Pujol M, Gavilondo J, Ayala M, Rodríguez M, González EM, Pérez L. Fighting cancer with plant-expressed pharmaceuticals. Trends Biotechnol 2007; 25:455-9. [PMID: 17869360 DOI: 10.1016/j.tibtech.2007.09.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2007] [Revised: 06/18/2007] [Accepted: 09/03/2007] [Indexed: 11/24/2022]
Abstract
Cancer is one of the most prevalent diseases worldwide, which explains why biological therapies for cancer are forecast to make up 35% of total recombinant pharmaceuticals by 2010. Because of the high demand for cancer drugs, the need to lower production costs and the constraints of present production technologies for recombinant pharmaceuticals (such as the difficulties involved in culturing bacteria, yeast and mammalian cells), attention has recently been focused on recombinant expression of pharmaceutical anti-cancer proteins in plants. This review aims to provide an update on the most recent publications about anti-cancer recombinant pharmaceuticals expressed in plants, as well as on the relevant technical issues, potential and prospects of this emerging production system.
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Affiliation(s)
- Merardo Pujol
- Plant Division, Center for Genetic Engineering and Biotechnology, P.O. Box 6162, C.P. 10600, Havana, Cuba.
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Abstract
This review examines the challenges of segregating biopharmed crops expressing pharmaceutical or veterinary agents from mainstream crops, particularly those destined for food or feed use. The strategy of using major food crops as production vehicles for the expression of pharmaceutical or veterinary agents is critically analysed in the light of several recent episodes of contamination of the human food chain by non-approved crop varieties. Commercially viable strategies to limit or avoid biopharming intrusion into the human food chain require the more rigorous segregation of food and non-food varieties of the same crop species via a range of either physical or biological methods. Even more secure segregation is possible by the use of non-food crops, non-crop plants or in vitro plant cultures as production platforms for biopharming. Such platforms already under development range from outdoor-grown Nicotiana spp. to glasshouse-grown Arabidopsis, lotus and moss. Amongst the more effective methods for biocontainment are the plastid expression of transgenes, inducible and transient expression systems, and physical containment of plants or cell cultures. In the current atmosphere of heightened concerns over food safety and biosecurity, the future of biopharming may be largely determined by the extent to which the sector is able to maintain public confidence via a more considered approach to containment and security of its plant production systems.
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Affiliation(s)
- Denis J Murphy
- Biotechnology Unit, Division of Biological Sciences, University of Glamorgan, Treforest, CF37 1DL, UK.
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Boehm R. Bioproduction of therapeutic proteins in the 21st century and the role of plants and plant cells as production platforms. Ann N Y Acad Sci 2007; 1102:121-34. [PMID: 17470916 PMCID: PMC7168112 DOI: 10.1196/annals.1408.009] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
abstract: In the last decade, the technique to genetically modify crop plants has gained more and more interest in terms of bioproduction of heterologous proteins. Plants have been discovered as a possible source for large amounts of cost effective recombinant protein. Main application fields are therapeutics for use in animal and human health, diagnostics, and technical enzymes. This review is focused on the recent progress in this field of molecular farming. After a comparison with hitherto established protein production systems, the advantages of plants as an alternative production system are discussed. An overview about the different host plants and possible expression strategies is given and the progress in commercialization of the techniques is highlighted. Finally, the role of plant cell cultures for the production of recombinant proteins is discussed.
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Affiliation(s)
- Robert Boehm
- Institute of Plant Molecular Physiology and Biotechnology, Karlrobert Kreiten-Str 13, Bonn, University of Bonn, Germany.
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Manuell AL, Beligni MV, Elder JH, Siefker DT, Tran M, Weber A, McDonald TL, Mayfield SP. Robust expression of a bioactive mammalian protein in Chlamydomonas chloroplast. PLANT BIOTECHNOLOGY JOURNAL 2007; 5:402-12. [PMID: 17359495 DOI: 10.1111/j.1467-7652.2007.00249.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
We have engineered the chloroplast of eukaryotic algae to produce a number of recombinant proteins, including human monoclonal antibodies, but, to date, have achieved expression to only 0.5% of total protein. Here, we show that, by engineering the mammalian coding region of bovine mammary-associated serum amyloid (M-SAA) as a direct replacement for the chloroplast psbA coding region, we can achieve expression of recombinant protein above 5% of total protein. Chloroplast-expressed M-SAA accumulates predominantly as a soluble protein, contains the correct amino terminal sequence and has little or no post-translational modification. M-SAA is found in mammalian colostrum and stimulates the production of mucin in the gut, acting in the prophylaxis of bacterial and viral infections. Chloroplast-expressed and purified M-SAA is able to stimulate mucin production in human gut epithelial cell lines. As Chlamydomonas reinhardtii is an edible alga, production of therapeutic proteins in this organism offers the potential for oral delivery of gut-active proteins, such as M-SAA.
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Affiliation(s)
- Andrea L Manuell
- The Department of Cell Biology and The Skaggs Institute for Chemical Biology, La Jolla, CA 92037, USA
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Griesbeck C, Kobl I, Heitzer M. Chlamydomonas reinhardtii: a protein expression system for pharmaceutical and biotechnological proteins. Mol Biotechnol 2007; 34:213-23. [PMID: 17172667 DOI: 10.1385/mb:34:2:213] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/1999] [Revised: 11/30/1999] [Accepted: 11/30/1999] [Indexed: 11/11/2022]
Abstract
Recombinant proteins have become more and more important for the pharmaceutical and chemical industry. Although various systems for protein expression have been developed, there is an increasing demand for inexpensive methods of large-scale production. Eukaryotic algae could serve as a novel option for the manufacturing of recombinant proteins, as they can be cultivated in a cheap and easy manner and grown to high cell densities. Being a model organism, the unicellular green alga Chlamydomonas reinhardtii has been studied intensively over the last decades and offers now a complete toolset for genetic manipulation. Recently, the successful expression of several proteins with pharmaceutical relevance has been reported from the nuclear and the chloroplastic genome of this alga, demonstrating its ability for biotechnological applications.
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Affiliation(s)
- Christoph Griesbeck
- Center of Excellence for Fluorescent Bioanalysis, Josef-Engert-Str. 9, D-93053 Regensburg, Germany.
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Spök A. Molecular farming on the rise – GMO regulators still walking a tightrope. Trends Biotechnol 2007; 25:74-82. [PMID: 17174425 DOI: 10.1016/j.tibtech.2006.12.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2006] [Revised: 10/12/2006] [Accepted: 12/05/2006] [Indexed: 10/23/2022]
Abstract
Recent increases in EU commercial and academic activities in molecular farming, and the proximity to market-stage of the first plant-made pharmaceuticals, represent a call to action for EU regulators. Drawing on the North American debate on molecular farming, it will be argued that both the rationale and the risks of molecular farming will differ significantly from those of first generation GM crops. Based on these differences, the suitability of the existing regulatory frameworks, which were developed in response to the arrival of earlier products, is discussed, and specific options for adapting the already complex EU regulatory system to cater for molecular farming are examined.
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Affiliation(s)
- Armin Spök
- IFZ-Inter-University Research Centre for Technology, Work and Culture, Schlögelgasse 2, A-8010 Graz, Austria
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Abstract
Maximizing the expression yields of recombinant whole antibodies and antibody fragments such as Fabs, single-chain Fvs and single-domain antibodies is highly desirable since it leads to lower production costs. Various eukaryotic and prokaryotic expression systems have been exploited to accommodate antibody expression but Escherichia coli systems have enjoyed popularity, in particular with respect to antibody fragments, because of their low cost and convenience. In many instances, product yields have been less than adequate and intrinsic and extrinsic variables have been investigated in an effort to improve yields. This review deals with various aspects of antibody expression in E. coli with a particular focus on single-domain antibodies.
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Affiliation(s)
- Mehdi Arbabi-Ghahroudi
- Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario.
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