RESUMO
The need for therapeutics to treat a plethora of medical conditions and diseases is on the rise and the demand for alternative approaches to mammalian-based production systems is increasing. Plant-based strategies provide a safe and effective alternative to produce biological drugs but have yet to enter mainstream manufacturing at a competitive level. Limitations associated with batch consistency and target protein production levels are present; however, strategies to overcome these challenges are underway. In this study, we apply state-of-the-art mass spectrometry-based proteomics to define proteome remodelling of the plant following agroinfiltration with bacteria grown under shake flask or bioreactor conditions. We observed distinct signatures of bacterial protein production corresponding to the different growth conditions that directly influence the plant defence responses and target protein production on a temporal axis. Our integration of proteomic profiling with small molecule detection and quantification reveals the fluctuation of secondary metabolite production over time to provide new insight into the complexities of dual system modulation in molecular pharming. Our findings suggest that bioreactor bacterial growth may promote evasion of early plant defence responses towards Agrobacterium tumefaciens (updated nomenclature to Rhizobium radiobacter). Furthermore, we uncover and explore specific targets for genetic manipulation to suppress host defences and increase recombinant protein production in molecular pharming.
Assuntos
Agrobacterium tumefaciens , Reatores Biológicos , Nicotiana , Proteômica , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/microbiologia , Nicotiana/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/metabolismo , Agricultura Molecular/métodos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteoma/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Immune checkpoint inhibitors (ICIs) are a class of immunotherapy agents capable of alleviating the immunosuppressive effects exerted by tumorigenic cells. The programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) immune checkpoint is one of the most ubiquitous checkpoints utilized by tumorigenic cells for immune evasion by inducing apoptosis and inhibiting the proliferation and cytokine production of T lymphocytes. Currently, the most frequently used ICIs targeting the PD-1/PD-L1 checkpoint include monoclonal antibodies (mAbs) pembrolizumab and nivolumab that bind to PD-1 on T lymphocytes and inhibit interaction with PD-L1 on tumorigenic cells. However, pembrolizumab and nivolumab are costly, and thus their accessibility is limited in low- and middle-income countries (LMICs). Therefore, it is essential to develop novel biomanufacturing platforms capable of reducing the cost of these two therapies. Molecular farming is one such platform utilizing plants for mAb production, and it has been demonstrated to be a rapid, low-cost, and scalable platform that can be potentially implemented in LMICs to diminish the exorbitant prices, ultimately leading to a significant reduction in cancer-related mortalities within these countries.
Assuntos
Antígeno B7-H1 , Nivolumabe , Nivolumabe/farmacologia , Receptor de Morte Celular Programada 1 , Agricultura Molecular , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , ImunoterapiaRESUMO
The outbreak of the SARS-CoV-2 global pandemic heightened the pace of vaccine development with various vaccines being approved for human use in a span of 24 months. The SARS-CoV-2 trimeric spike (S) surface glycoprotein, which mediates viral entry by binding to ACE2, is a key target for vaccines and therapeutic antibodies. Plant biopharming is recognized for its scalability, speed, versatility, and low production costs and is an increasingly promising molecular pharming vaccine platform for human health. We developed Nicotiana benthamiana-produced SARS-CoV-2 virus-like particle (VLP) vaccine candidates displaying the S-protein of the Beta (B.1.351) variant of concern (VOC), which triggered cross-reactive neutralising antibodies against Delta (B.1.617.2) and Omicron (B.1.1.529) VOCs. In this study, immunogenicity of the VLPs (5 µg per dose) adjuvanted with three independent adjuvants i.e. oil-in-water based adjuvants SEPIVAC SWETM (Seppic, France) and "AS IS" (Afrigen, South Africa) as well as a slow-release synthetic oligodeoxynucleotide (ODN) adjuvant designated NADA (Disease Control Africa, South Africa) were evaluated in New Zealand white rabbits and resulted in robust neutralising antibody responses after booster vaccination, ranging from 1:5341 to as high as 1:18204. Serum neutralising antibodies elicited by the Beta variant VLP vaccine also showed cross-neutralisation against the Delta and Omicron variants with neutralising titres ranging from 1:1702 and 1:971, respectively. Collectively, these data provide support for the development of a plant-produced VLP based candidate vaccine against SARS-CoV-2 based on circulating variants of concern.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Coelhos , Animais , Humanos , SARS-CoV-2 , Agricultura Molecular , COVID-19/prevenção & controle , Adjuvantes Imunológicos , Anticorpos Neutralizantes , África do Sul , Anticorpos Antivirais , Glicoproteína da Espícula de Coronavírus/genética , Imunogenicidade da VacinaRESUMO
Epidermal growth factor (EGF) is a known signaling cue essential towards the development and organoid biofabrication particularly for exocrine glands. This study developed an in vitro EGF delivery platform with Nicotiana benthamiana plant-produced EGF (P-EGF) encapsulated on hyaluronic acid/alginate (HA/Alg) hydrogel to improve the effectiveness of glandular organoid biofabrication in short-term culture systems. Primary submandibular gland epithelial cells were treated with 5 - 20 ng/mL of P-EGF and commercially available bacteria-derived EGF (B-EGF). Cell proliferation and metabolic activity were measured by MTT and luciferase-based ATP assays. P-EGF and B-EGF 5 - 20 ng/mL promoted glandular epithelial cell proliferation during 6 culture days on a comparable fashion. Organoid forming efficiency and cellular viability, ATP-dependent activity and expansion were evaluated using two EGF delivery systems, HA/Alg-based encapsulation and media supplementation. Phosphate buffered saline (PBS) was used as a control vehicle. Epithelial organoids fabricated from PBS-, B-EGF-, and P-EGF-encapsulated hydrogels were characterized genotypically, phenotypically and by functional assays. P-EGF-encapsulated hydrogel enhanced organoid formation efficiency and cellular viability and metabolism relative to P-EGF supplementation. At culture day 3, epithelial organoids developed from P-EGF-encapsulated HA/Alg platform contained functional cell clusters expressing specific glandular epithelial markers such as exocrine pro-acinar (AQP5, NKCC1, CHRM1, CHRM3, Mist1), ductal (K18, Krt19), and myoepithelial (α-SMA, Acta2), and possessed a high mitotic activity (38-62% Ki67 cells) with a large epithelial progenitor population (â¼70% K14 cells). The P-EGF encapsulation strikingly upregulated the expression of pro-acinar AQP5 cells through culture time when compared to others (B-EGF, PBS). Thus, the utilization of Nicotiana benthamiana in molecular farming can produce EGF biologicals amenable to encapsulation in HA/Alg-based in vitro platforms, which can effectively and promptly induce the biofabrication of exocrine gland organoids.
Assuntos
Fator de Crescimento Epidérmico , Hidrogéis , Fator de Crescimento Epidérmico/farmacologia , Agricultura Molecular , Organoides , Ácido Hialurônico/farmacologia , Trifosfato de AdenosinaRESUMO
Many plant virus-like particles (VLPs) utilized in nanotechnology are 30-nm icosahedrons. To expand the VLP platforms, we produced VLPs of Cytoplasmic type citrus leprosis virus (CiLV-C) in Nicotiana benthamiana. We were interested in CiLV-C because of its unique bacilliform shape (60-70 nm × 110-120 nm). The CiLV-C capsid protein (p29) gene was transferred to the pTRBO expression vector transiently expressed in leaves. Stable VLPs were formed, as confirmed by agarose gel electrophoresis, transmission electron microscopy and size exclusion chromatography. Interestingly, the morphology of the VLPs (15.8 ± 1.3 nm icosahedral particles) differed from that of the native bacilliform particles indicating that the assembly of native virions is influenced by other viral proteins and/or the packaged viral genome. The smaller CiLV-C VLPs will also be useful for structure-function studies to compare with the 30-nm icosahedrons of other VLPs.
Assuntos
Citrus , Vírus de RNA , Rhabdoviridae , Agricultura Molecular , Vírus de RNA/genética , Vírion/genéticaRESUMO
Transient expression of recombinant proteins in plants is being used as a platform for production of therapeutic proteins. Benefits of this system include a reduced cost of drug development, rapid delivery of new products to the market, and an ability to provide safe and efficacious medicines for diseases. Although plant-based production systems offer excellent potential for therapeutic protein production, barriers, such as plant host defense response, exist which negatively impact the yield of product. Here we provide a protocol using tandem mass tags and mass spectrometry-based proteomics to quickly and robustly quantify the change in abundance of host defense proteins produced during the production process. These proteins can then become candidates for genetic manipulation to create host plants with reduced plant defenses capable of producing higher therapeutic protein yields.
Assuntos
Agrobacterium tumefaciens , Agricultura Molecular , Agrobacterium tumefaciens/metabolismo , Agricultura Molecular/métodos , Plantas/genética , Plantas Geneticamente Modificadas/genética , Proteômica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Nicotiana/metabolismoRESUMO
A variety of methods for studying glandular leaf hairs (trichomes) as multicellular micro-organs are well established for synthetic biology platforms like tobacco or tomato but rather rare for nonglandular and usually single-celled trichomes of the model plant Arabidopsis thaliana. A thorough isolation of-ideally intact-trichomes is decisive for further biochemical and genomic analyses of primary and secondary metabolic compounds, enzymes, and especially transcripts to monitor initial success of an engineering approach. While isolation of tomato or tobacco trichomes is rather easy, by simply freezing whole plants in liquid nitrogen and brushing off trichomes, this approach does not work for Arabidopsis. This is mainly due to damage of trichome cells during the collection procedure and very low yield. Here, we provide a robust method for a virtually epithelial cell-free isolation of Arabidopsis trichomes. This method is then joined with an RNA isolation protocol to perform mRNA analysis on extracts of the isolated trichomes using a semi-quantitative RT-PCR setup.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Agricultura Molecular , Folhas de Planta/genética , Folhas de Planta/metabolismo , Biologia Sintética , Tricomas/genética , Tricomas/metabolismoRESUMO
Agroinfiltration in Nicotiana benthamiana is widely used to transiently express heterologous proteins in plants. However, the state of Agrobacterium itself is not well studied in agroinfiltrated tissues, despite frequent studies of immunity genes conducted through agroinfiltration. Here, we generated a bioluminescent strain of Agrobacterium tumefaciens GV3101 to monitor the luminescence of Agrobacterium during agroinfiltration. By integrating a single copy of the lux operon into the genome, we generated a stable 'AgroLux' strain, which is bioluminescent without affecting Agrobacterium growth in vitro and in planta. To illustrate its versatility, we used AgroLux to demonstrate that high light intensity post infiltration suppresses both Agrobacterium luminescence and protein expression. We also discovered that AgroLux can detect Avr/Cf-induced immune responses before tissue collapse, establishing a robust and rapid quantitative assay for the hypersensitive response (HR). Thus, AgroLux provides a non-destructive, versatile and easy-to-use imaging tool to monitor both Agrobacterium and plant responses.
Assuntos
Agrobacterium tumefaciens/genética , Agricultura Molecular/métodos , Nicotiana/microbiologia , Imunidade Vegetal , Proteínas Recombinantes/genética , Agrobacterium tumefaciens/crescimento & desenvolvimento , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Luz , Medições Luminescentes , Microrganismos Geneticamente Modificados , Óperon , Folhas de Planta/microbiologia , Proteínas Recombinantes/metabolismo , Nicotiana/imunologiaRESUMO
We have constructed two intra-molecularly shuffled promoters, namely S100 and D100. The S100 recombinant promoter (621 bp) was generated by ligation of 250 bp long upstream activation sequence (UAS) of Strawberry vein banding virus (SV10UAS; - 352 to - 102 relative to TSS) with its 371 bp long TATA containing core promoter domain (SV10CP; - 352 to + 19). Likewise, 726 bp long D100 promoter was constructed by fusion of 170 bp long UAS of Dahlia mosaic virus (DaMV14UAS; - 203 to - 33) with its 556 bp long core promoter domain (DaMV4CP; - 474 to + 82). S100 and D100 promoters showed 1.8 and 2.2 times stronger activities than that of the CaMV35S promoter. The activity of the promoters is comparable to that of the CaMV35S2 promoter. Transcript analysis employing qRT-PCR and histochemical assays supported the above findings. Abscisic acid and salicylic acid induce the activity of the D100 promoter. Leaf protein obtained from Nicotiana tabacum plant expressing NSD2 gene (Nigella sativa L. defensin 2) driven by the D100 promoter showed antifungal activity against Alternaria alternata and Phoma exigua var. exigua and antibacterial activity against Pseudomonas aeruginosa and Staphylococcus aureus. Strong S100 and D100 promoters have potential to become efficient candidates for plant metabolic engineering and molecular pharming.
Assuntos
Caulimovirus/genética , Defensinas/genética , Nicotiana/genética , Proteínas de Plantas/genética , Regiões Promotoras Genéticas , Proteínas Virais/genética , Ácido Abscísico/farmacologia , Agrobacterium tumefaciens/genética , Agrobacterium tumefaciens/metabolismo , Agrobacterium tumefaciens/virologia , Alternaria/efeitos dos fármacos , Alternaria/crescimento & desenvolvimento , Ascomicetos/efeitos dos fármacos , Ascomicetos/crescimento & desenvolvimento , Caulimovirus/metabolismo , Defensinas/metabolismo , Defensinas/farmacologia , Expressão Gênica , Humanos , Testes de Sensibilidade Microbiana , Agricultura Molecular/métodos , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/virologia , Proteínas de Plantas/metabolismo , Proteínas de Plantas/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Ácido Salicílico/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Nicotiana/efeitos dos fármacos , Nicotiana/metabolismo , Nicotiana/virologia , Transformação Genética , Transgenes , Proteínas Virais/metabolismoRESUMO
Gastrointestinal infections caused by Clostridium difficile lead to significant impact in terms of morbidity and mortality, causing from mild symptoms, such as a low-grade fever, watery stools, and minor abdominal cramping as well as more severe symptoms such as bloody diarrhea, pseudomembrane colitis, and toxic megacolon. Vaccination is a viable approach to fight against C. difficile and several efforts in this direction are ongoing. Plants are promising vaccine biofactories offering low cost, enhanced safety, and allow for the formulation of oral vaccines. Herein, the CdeM protein, which is a spore antigen associated with immunoprotection against C. difficile, was selected to begin the development of plant-based vaccine candidates. The vaccine antigen is based in a fusion protein (LTB-CdeM), carrying the CdeM antigen, fused to the carboxi-terminus of the B subunit of the Escherichia coli heat-labile enterotoxin (LTB) as a mucosal immunogenic carrier. LTB-CdeM was produced in plants using a synthetic optimized gene according codon usage and mRNA stability criteria. The obtained transformed tobacco lines produced the LTB-CdeM antigen in the range of 52-90 µg/g dry weight leaf tissues. The antigenicity of the plant-made LTB-CdeM antigen was evidenced by GM1-ELISA and immunogenicity assessment performed in test mice revealed that the LTB-CdeM antigen is orally immunogenic inducing humoral responses against CdeM epitopes. This report constitutes the first step in the development of plant-based vaccines against C. difficile infection.
Assuntos
Antígenos de Bactérias , Clostridioides difficile/genética , Plantas Geneticamente Modificadas , Esporos Bacterianos/genética , Vacinas de Plantas Comestíveis , Administração Oral , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Enterotoxinas/genética , Proteínas de Escherichia coli/genética , Imunoglobulina G/sangue , Camundongos , Camundongos Endogâmicos BALB C , Agricultura Molecular , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Vacinas de Plantas Comestíveis/genética , Vacinas de Plantas Comestíveis/imunologia , Vacinas de Plantas Comestíveis/metabolismoRESUMO
Recombinant proteins play an important role in many areas of our lives. For example, recombinant enzymes are used in the food and chemical industries and as high-quality proteins for research, diagnostic and therapeutic applications. The production of recombinant proteins is still dominated by expression systems based on microbes and mammalian cells, although the manufacturing of recombinant proteins in plants - known as molecular farming - has been promoted as an alternative, cost-efficient strategy for three decades. Several molecular farming products have reached the market, but the number of success stories has been limited by industrial inertia driven by perceptions of low productivity, the high cost of downstream processing, and regulatory hurdles that create barriers to translation. Here, we discuss the technical and economic factors required for the successful commercialization of molecular farming, and consider potential future directions to enable the broader application of production platforms based on plants.
Assuntos
Agricultura Molecular , Proteínas de Plantas/análise , Plantas Geneticamente Modificadas/química , Proteínas Recombinantes/análise , BiotecnologiaRESUMO
We set out to assess the NIH/3T3 cell proliferation activity of Arabidopsis oil body-expressed recombinant oleosin-hEGF-hEGF protein. Normally, human epidermal growth factor (hEGF) is purified through complex process, however, oleosin fusion technology provides an inexpensive and scalable platform for its purification. Under a phaseolin promoter, we concatenated oleosin gene to double hEGF (hEGF-hEGF) with plant-preferred codons in the expression vectors and the construct was transformed into Arabidopsis thaliana (Arabidopsis). The transgenic Arabidopsis was validated by RT-PCR and the content of recombinant protein oleosin-hEGF-hEGF was quantified by western blot. Subsequently, the proliferation assay and transdermal absorption were determined by MTT method and immunohistochemical staining, respectively. First, the expression level of hEGF was recorded to be 14.83-ng/µL oil body and due to smaller size transgenic oil bodies expressing the recombinant oleosin-hEGF-hEGF, they were more skin permeable than those of control. Second, via the staining intensity of transgenic oil bodies was greater than EGF at all time points via immunohistochemical staining in transdermal absorption process. Lastly, activity assays of oil bodies expressed oleosin-hEGF-hEGF indicated that they stimulated the NIH/3T3 cell proliferation activity. Our results revealed oil-body-expressed oleosin-hEGF-hEGF was potential new material having implications in the field of medicine.
Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Proteínas Recombinantes/metabolismo , Pele/metabolismo , Animais , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Proliferação de Células , Fator de Crescimento Epidérmico/química , Fator de Crescimento Epidérmico/genética , Humanos , Camundongos , Agricultura Molecular , Células NIH 3T3 , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Regiões Promotoras Genéticas , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , CicatrizaçãoRESUMO
One of the milestones of vaccinology is the depletion of the global impact of Poliomyelitis. The current vaccines to deal with Polio comprise the Sabin and Salk formulations. The main limitation of the former is the use of attenuated viruses that can revert into pathogenic forms, whereas the latter is more expensive and induces no protection in the intestinal tract; the site of virus replication. Genetically engineered plants cope with such limitations. In addition, they offer a low-cost alternative for production, storage and delivery of vaccines. This technology has been narrowly applied in the development of Polio vaccines. Herein, we explored the ability of tobacco cells to express the immunogenic VP1, VP2, VP3, and VP4 Polio antigens, which are relevant for vaccine development. Evidence on the expression of the plant-made Polio VPs is presented and an immunogenicity assessment proved their capacity to induce local and systemic humoral responses when administered by subcutaneous and oral routes. The plant-made VPs will be useful in the development of low-cost vaccine formulations able to induce effective mucosal immunity without the risks associated to the use of attenuated viruses; therefore there is a potential for this technology to contribute toward Polio eradication.
Assuntos
Proteínas do Capsídeo , Nicotiana/genética , Vacina Antipólio Oral , Poliovirus , Vacinas de Subunidades Antigênicas , Animais , Anticorpos Antivirais/análise , Anticorpos Antivirais/sangue , Antígenos Virais/genética , Antígenos Virais/imunologia , Antígenos Virais/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/imunologia , Proteínas do Capsídeo/metabolismo , Fezes/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Agricultura Molecular , Plantas Geneticamente Modificadas/genética , Poliomielite/prevenção & controle , Poliomielite/virologia , Poliovirus/genética , Poliovirus/imunologia , Vacina Antipólio Oral/genética , Vacina Antipólio Oral/imunologia , Vacina Antipólio Oral/metabolismo , Vacinas de Subunidades Antigênicas/genética , Vacinas de Subunidades Antigênicas/imunologia , Vacinas de Subunidades Antigênicas/metabolismoRESUMO
Plant molecular farming (PMF) is a convenient and cost-effective way to produce high-value recombinant proteins that can be used in the production of a range of health products, from pharmaceutical therapeutics to cosmetic products. New plant breeding techniques (NPBTs) provide a means to enhance PMF systems more quickly and with greater precision than ever before. However, the feasibility, regulatory standing and social acceptability of both PMF and NPBTs are in question. This paper explores the perceptions of key stakeholders on two European Union (EU) Horizon 2020 programmes-Pharma-Factory and Newcotiana-towards the barriers and facilitators of PMF and NPBTs in Europe. One-on-one qualitative interviews were undertaken with N = 20 individuals involved in one or both of the two projects at 16 institutions in seven countries (Belgium, France, Germany, Italy, Israel, Spain and the UK). The findings indicate that the current EU regulatory environment and the perception of the public towards biotechnology are seen as the main barriers to scaling-up PMF and NPBTs. Competition from existing systems and the lack of plant-specific regulations likewise present challenges for PMF developing beyond its current niche. However, respondents felt that the communication of the benefits and purpose of NPBT PMF could provide a platform for improving the social acceptance of genetic modification. The importance of the media in this process was highlighted. This article also uses the multi-level perspective to explore the ways in which NPBTs are being legitimated by interested parties and the systemic factors that have shaped and are continuing to shape the development of PMF in Europe.
Assuntos
Agricultura Molecular , Nicotiana/crescimento & desenvolvimento , Melhoramento Vegetal , Plantas/genética , Biotecnologia , União Europeia , Edição de Genes , Engenharia Genética/tendências , Humanos , Desenvolvimento Vegetal/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimentoRESUMO
In the past decade, interest in the production of recombinant pharmaceutical proteins in plants has tremendously progressed because plants do not harbor mammalian viruses, are economically competitive, easily scalable, and capable of carrying out complex post-translational modifications required for recombinant pharmaceutical proteins. Mucuna bracteata is an essential perennial cover crop species widely planted as an underground cover in oil palm and rubber plantations. As a legume, they have high biomass, thrive in its habitat, and can fix nitrogen. Thus, M. bracteata is a cost-efficient crop that shows ideal characteristics as a platform for mass production of recombinant protein. In this study, we established a new platform for the transient production of a recombinant protein in M. bracteata via vacuum-assisted agro-infiltration. Five-week-old M. bracteata plants were vacuum infiltrated with Agrobacterium tumefaciens harboring a plasmid that encodes for an anti-toxoplasma immunoglobulin (IgG) under different parameters, including trifoliate leaf positional effects, days to harvest post-infiltration, and the Agrobacterium strain used. Our results showed that vacuum infiltration of M. bracteata plant with A. tumefaciens strain GV3101 produced the highest concentration of heterologous protein in its bottom trifoliate leaf at 2 days post-infiltration. The purified anti-toxoplasma IgG was then analyzed using Western blot and ELISA. It was demonstrated that, while structural heterogeneity existed in the purified anti-toxoplasma IgG from M. bracteata, its transient expression level was two-fold higher than the model platform, Nicotiana benthamiana. This study has laid the foundation towards establishing M. bracteata as a potential platform for the production of recombinant pharmaceutical protein.
Assuntos
Imunoglobulina G/biossíntese , Agricultura Molecular/métodos , Mucuna/genética , Agrobacterium tumefaciens/genética , Expressão Gênica , Técnicas de Transferência de Genes/instrumentação , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Imunoglobulina G/isolamento & purificação , Mucuna/metabolismo , Plantas Geneticamente Modificadas/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Toxoplasma/imunologia , Transformação BacterianaRESUMO
Molecular farming increasingly uses the tobacco relative Nicotiana benthamiana for production of recombinant proteins through transient expression. Several proteins are produced efficiently with this expression platform, but yields for other proteins are often very low. These low yields are frequently due to endogenous proteases. The latest genome annotations indicate that N. benthamiana encodes for at least 1243 putative proteases that probably act redundantly and consecutively on substrates in different subcellular compartments. Here, we discuss the N. benthamiana protease repertoire that may affect recombinant protein production and recent advances in protease depletion strategies to increase recombinant protein production in N. benthamiana.
Assuntos
Agricultura Molecular , Nicotiana/genética , Endopeptidases , Peptídeo Hidrolases , Plantas Geneticamente Modificadas , Proteínas RecombinantesRESUMO
The use of plants for the production of virus-like nanoparticles (VNPs) dates back to separating natural empty capsids of plant viruses from whole virions nearly 70 years ago, through to the present use of transgenic plants or recombinant Agrobacterium tumefaciens and/or plant virus-derived vectors for the transient expression of engineered viral or other structural proteins in plants-a production system also known as molecular farming. Plant production of heterologous proteins has major advantages in terms of convenience-whole plants are generally used, and processes do not need to be sterile-and cost, as bulk biomass production is significantly cheaper than by any other method. Plant-made VNPs in current use for nanotechnology include whole virions and naturally occurring empty capsids of plant viruses, and particles made by reassembly of coat protein (CP) purified from virions or by recombinant expression. Engineered VNP-forming animal or human virus CPs expressed in plants include L1 protein from human papillomaviruses, human norovirus CP, hepatitis B surface and core antigens, influenza virus HA protein and HIV Gag polyprotein forming large enveloped particles by budding, orbi- and rotavirus particles that require assembly of four co-expressed proteins, and polio- and foot and mouth disease viruses which require proteolytic processing of a polyprotein precursor to form 4-component VNPs. Both plant and animal virus-derived plant-made VNPs can be used for surface and internal display of heterologous peptides or even whole proteins. A significant recent development has been the production of pseudovirions in plants, comprising plant or animal virus CPs and RNA or DNA pseudogenomes that can be used to deliver nucleic acid payloads into cultured cells or specific tissues or tumors in whole animals. This article is characterized under: Biology-Inspired Nanomaterials > Protein and Virus-Based Structures Therapeutic Approaches and Drug Discovery > Emerging Technologies Diagnostic Tools > in vivo Nanodiagnostics and Imaging.
Assuntos
Agricultura Molecular , Nanopartículas , Vírion , Animais , Indicadores e Reagentes , Plantas Geneticamente Modificadas , VacinasRESUMO
The successful production of recombinant enzymes by tobacco transplastomic plants must maintain compatibility of the heterologous enzyme with chloroplast metabolism and its long-time enzyme stability. Based on previous reports, it has been taken for granted that following biolistic-transformation, homoplasticity could be obtained from the initially heteroplastic state following successive rounds of selection in the presence of the selection agent. However, several studies indicated that this procedure does not always ensure the complete elimination of unmodified wild-type plastomes. The present study demonstrates that CelK1 transplastomic plants, which were photosyntetically as active as untransformed ones, remain heteroplastomic even after repeated selection steps and that this state does not impair the relatively high-level production of the recombinant enzyme. In fact, even in the heteroplastomic state, the recombinant protein represented about 6% of the total soluble proteins (TSP). Moreover, our data also show that, while the recombinant endoglucanase undergoes phosphorylation, this post-translation modification does not have any significant impact on the enzymatic activity. Biomass storage might be required whenever the enzyme extraction process could not be performed immediately following the harvest of tobacco mature plants. In this respect, we have observed that enzyme activity in the detached leaves stored at 4 °C is maintained up to 20 weeks without significant loss of activity. These findings may have major implications in the future of chloroplast genetic engineering-based molecular farming to produce industrial enzymes in transplastomic plants.
Assuntos
Celulase/biossíntese , Cloroplastos/genética , Agricultura Molecular , Nicotiana/enzimologia , Nicotiana/genética , Celulase/genética , Engenharia Genética , Microbiologia Industrial/métodos , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Proteoma , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genéticaRESUMO
Plants offer fast, flexible and easily scalable alternative platforms for the production of pharmaceutical proteins, but differences between plant and mammalian N-linked glycans, including the presence of ß-1,2-xylose and core α-1,3-fucose residues in plants, can affect the activity, potency and immunogenicity of plant-derived proteins. Nicotiana benthamiana is widely used for the transient expression of recombinant proteins so it is desirable to modify the endogenous N-glycosylation machinery to allow the synthesis of complex N-glycans lacking ß-1,2-xylose and core α-1,3-fucose. Here, we used multiplex CRISPR/Cas9 genome editing to generate N. benthamiana production lines deficient in plant-specific α-1,3-fucosyltransferase and ß-1,2-xylosyltransferase activity, reflecting the mutation of six different genes. We confirmed the functional gene knockouts by Sanger sequencing and mass spectrometry-based N-glycan analysis of endogenous proteins and the recombinant monoclonal antibody 2G12. Furthermore, we compared the CD64-binding affinity of 2G12 glycovariants produced in wild-type N. benthamiana, the newly generated FX-KO line, and Chinese hamster ovary (CHO) cells, confirming that the glyco-engineered antibody performed as well as its CHO-produced counterpart.
Assuntos
Anticorpos Monoclonais/metabolismo , Nicotiana/enzimologia , Proteínas de Plantas/metabolismo , Polissacarídeos/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Amplamente Neutralizantes , Células CHO , Sistemas CRISPR-Cas , Cricetulus , Fucose/metabolismo , Fucosiltransferases/genética , Fucosiltransferases/metabolismo , Edição de Genes , Técnicas de Inativação de Genes , Glicosilação , Anticorpos Anti-HIV , Agricultura Molecular , Pentosiltransferases/genética , Pentosiltransferases/metabolismo , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Proteínas Recombinantes , Nicotiana/genética , Xilose/metabolismo , UDP Xilose-Proteína XilosiltransferaseRESUMO
The constant demand for new antibiotic drugs has driven efforts by the scientific community to prospect for peptides with a broad spectrum of action. In this context, antimicrobial peptides (AMPs) have acquired great scientific importance in recent years due to their ability to possess antimicrobial and immunomodulatory activity. In the last two decades, plants have attracted the interest of the scientific community and industry as regards their potential as biofactories of heterologous proteins. One of the most promising approaches is the use of viral vectors to maximize the transient expression of drugs in the leaves of the plant Nicotiana benthamiana. Recently, the MagnifectionTM expression system was launched. This sophisticated commercial platform allows the assembly of the viral particle in leaf cells and the systemic spread of heterologous protein biosynthesis in green tissues caused by Agrobacterium tumefaciens "gene delivery method". The system also presents increased gene expression levels mediated by potent viral expression machinery. These characteristics allow the mass recovery of heterologous proteins in the leaves of N. benthamiana in 8 to 10 days. This system was highly efficient for the synthesis of different classes of pharmacological proteins and contains enormous potential for the rapid and abundant biosynthesis of AMPs.