2,050 research outputs found
Research Tool Patents and Free-Libre Biotechnology: A Unified Perspective.
This paper proposes a unified conceptual framework to analyse the multiple role and consequences of patents in the case of biotechnology research tools. We argue that the knowledge/information and independent/complementary nature of research tools define heterogeneous frameworks in which the patent system plays different roles. In particular, using the analogy with the free-libre open source movement in software, we show that patents can promote open innovation by ensuring the freedom of some pieces of knowledge. A strong conclusion of the paper is therefore that, against common belief, an adequate use of the patent system may contribute to preserving freedom of access to upstream research tools within a framework that we call free-libre biotechnology.Intellectual property rights, sequential innovation, open source, life science, collective invention.
Characterization of VRC01, a potent and broadly neutralizing anti-HIV mAb, produced in transiently and stably transformed tobacco
The proposed clinical trial in Africa of VRC01, a potent broadly neutralizing antibody (bNAb)
capable of neutralizing 91% of known HIV-1 isolates, raises concerns about testing a treatment
which will be too expensive to be accessible by the most important target population, the poor in
under-developed regions such as sub-Saharan Africa. Here, we report the expression of VRC01
in plants as an economic alternative to conventional mammalian-cell-based production
platforms. The heavy and light chain genes of VRC01 were cloned onto a single vector, pTRAk.2,
which was transformed into Nicotiana benthamiana or Nicotiana tabacum using transient and
stable expression production systems respectively. VRC01 has been successfully expressed
transiently in plants with expression level of approximately 80 mg antibody/kg; stable transgenic
lines expressing up to 100 mg antibody/kg were also obtained. Plant-produced VRC01 from
both systems showed a largely homogeneous N-glycosylation profile with a single dominant
glycoform. The binding kinetics to gp120 IIIB (approximately 1 nM), neutralization of HIV-1 BaL or
a panel of 10 VRC01-sensitive HIV-1 Env pseudoviruses of VRC01 produced in transient and
stable plants were also consistent with VRC01 from HEK cells
Fair value on commons-based intellectual property assets: Lessons of an estimation over Linux kernel.
Open source describes practices in production and development that promote access to the end product's source materials, spreading development burden amongst individuals and companies. This model has resulted in a large and efficient ecosystem and unheralded software innovation, freely available to society. Open source methods are also increasingly being applied in other fields of endeavour, such as biotechnology or cultural production. But under financial reporting framework, general volunteer activity is not reflected on financial statements. As a result, there is not value of volunteer contributions and there is also no single source for cost estimates of how much it has taken to develop an open source technology. This volunteer activity encloses not only individuals but corporations developing and contributing open source products. Standard methodology for reporting open source asset valuation is needed and must include value creation from the perspective of the different stakeholders.FLOSS, commons, accounting standards, financial reporting
Production of the main celiac disease autoantigen by transient expression in Nicotiana benthamiana
Celiac Disease (CD) is a gluten sensitive enteropathy that remains widely undiagnosed and implementation of massive screening tests is needed to reduce the long term complications associated to untreated CD. The main CD autoantigen, human tissue transglutaminase (TG2), is a challenge for the different expression systems available since its cross-linking activity affects cellular processes. Plant-based transient expression systems can be an alternative for the production of this protein. In this work, a transient expression system for the production of human TG2 in Nicotiana benthamiana leaves was optimized and reactivity of plant-produced TG2 in CD screening test was evaluated. First, a subcellular targeting strategy was tested. Cytosolic, secretory, endoplasmic reticulum (C-terminal SEKDEL fusion) and vacuolar (C-terminal KISIA fusion) TG2 versions were transiently expressed in leaves and recombinant protein yields were measured. ER-TG2 and vac-TG2 levels were 9- to 16-fold higher than their cytosolic and secretory counterparts. As second strategy, TG2 variants were co-expressed with a hydrophobic elastin-like polymer (ELP) construct encoding for 36 repeats of the pentapeptide VPGXG in which the guest residue X were V and F in ratio 8:1. Protein bodies (PB) were induced by the ELP, with a consequent two-fold-increase in accumulation of both ER-TG2 and vac-TG2. Subsequently, ER-TG2 and vac-TG2 were produced and purified using immobilized metal ion affinity chromatography. Plant purified ER-TG2 and vac-TG2 were recognized by three anti-TG2 monoclonal antibodies that bind different epitopes proving that plant-produced antigen has immunochemical characteristics similar to those of human TG2. Lastly, an ELISA was performed with sera of CD patients and healthy controls. Both vac-TG2 and ER-TG2 were positively recognized by IgA of CD patients while they were not recognized by serum from non-celiac controls. These results confirmed the usefulness of plant-produced TG2 to develop screening assays. In conclusion, the combination of subcellular sorting strategy with co-expression with a PB inducing construct was sufficient to increase TG2 protein yields. This type of approach could be extended to other problematic proteins, highlighting the advantages of plant based production platforms.Fil: Marin Viegas, Vanesa Soledad. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Acevedo, Gonzalo Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Bayardo, Mariela Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Chirdo, Fernando Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Estudios Inmunológicos y Fisiopatológicos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Estudios Inmunológicos y Fisiopatológicos; ArgentinaFil: Petruccelli, Silvana. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin
Sensory evaluation and microbial status of meat floss from West African Dwarf Goats fed graded levels of broiler litter
This study was conducted to evaluate the effects of dietary inclusion levels of Broiler Litter (BL) on meat quality of West Africa Dwarf (WAD) goats. Five complete diets were formulated using BL to replace 40 % composition of Cottonseed Cake (CSC) as dietary protein source at 0, 25, 50, 75 and 100 % levels, thus each level of replacement served as a treatment. Thirty WAD bucks with average weight of 10.57±0.42 kg were randomly allotted to five treatments in a randomized complete block design (RCBD). After feeding trials and digestibility studies, the bucks were humanly slaughtered and two kilograms of meat from uniform parts (hind leg and loin) of each buck were processed to Meat Floss (Dambun nama) and evaluated for proximate, sensory qualities and microbial status during storage for 60 days at room temperature. Twenty semi-trained panellists were used to evaluate the processed meat, using a five-point hedonic scale, Total Aerobic Plate Counts (TAPC) and Total Coliform Counts (TCC) was also determined. The result revealed that proximate nutrients composition of fresh Chevon was not significantly (p>0.05) different in all the treatments. The results of sensory parameters revealed that aroma, taste, colour, tenderness, juiciness and acceptability were significantly (p<0.05) affected by levels of BL inclusions. Similarly, there was also interaction (p<0.05) between levels of CSC replacement with broiler litter and time of storage of Dambun nama on sensory parameters. It was concluded that replacing up to 50 % of CSC with BL improved meat sensory qualities
Expression and immunogenicity of the mycobacterial Ag85B/ESAT-6 antigens produced in transgenic plants by elastin-like peptide fusion strategy.
International audienceThis study explored a novel system combining plant-based production and the elastin-like peptide (ELP) fusion strategy to produce vaccinal antigens against tuberculosis. Transgenic tobacco plants expressing the mycobacterial antigens Ag85B and ESAT-6 fused to ELP (TBAg-ELP) were generated. Purified TBAg-ELP was obtained by the highly efficient, cost-effective, inverse transition cycling (ICT) method and tested in mice. Furthermore, safety and immunogenicity of the crude tobacco leaf extracts were assessed in piglets. Antibodies recognizing mycobacterial antigens were produced in mice and piglets. A T-cell immune response able to recognize the native mycobacterial antigens was detected in mice. These findings showed that the native Ag85B and ESAT-6 mycobacterial B- and T-cell epitopes were conserved in the plant-expressed TBAg-ELP. This study presents the first results of an efficient plant-expression system, relying on the elastin-like peptide fusion strategy, to produce a safe and immunogenic mycobacterial Ag85B-ESAT-6 fusion protein as a potential vaccine candidate against tuberculosis
Some Policy Issues on Open Source and Proprietary Software
Software industry is a fast growing sector of the economy which is undergoing significant changes both for the presence of the open source mode of production and for the challenges of globalization and convergence with other industries. This paper analyses the role of open source software (OSS) on competition and innovation in the software industry and debates the economic rationales for promoting the adoption of OSS by national and local governments.software industry, open source software, patent system
Feasibility of Unwaxed and Waxed Banana (Musa acuminata x balbisiana) Pseudostem Fibers as Alternative Dental Floss Material
Oral health, waste management, and sustainability are prevalent issues faced by developing countries. Relative to these concerns, there remains a need for oral hygiene essentials that are both effective and environmentally responsible. This study aims to explore the feasibility of banana pseudostem fibers (BPF) as an alternative material for sustainable dental floss in terms of two physical properties, namely, tensile strength and elongation at break. Fibers were mechanically extracted from the outermost sheaths of banana pseudostems to produce two sample groups, unwaxed BPF and waxed BPF, the latter comprising fibers that were coated with a mixture of two parts coconut oil and one part candelilla wax. Both sample groups were tested for tensile strength and elongation at break. According to the mean and SD of both groups and one-way MANOVA, unwaxed BPF had significantly higher tensile strength and elongation at break than waxed BPF, revealing that the wax coating process diminished the physical properties of the BPF due to thermal degradation. Furthermore, the application of the coconut oil-candelilla wax coating was found to have a large effect on tensile strength and a small effect on elongation at break. Results show that there is potential in BPF to be an alternative material for dental floss in relation to the examined properties, although it may not be a substitute for synthetic dental floss material by itself. Modifying the fiber extraction and wax coating processes involved and assessing the chemical properties of the material are also recommended for further research
STUDIES OF ERGOT ALKALOID BIOSYNTHESIS GENES IN CLAVICIPITACEOUS FUNGI
Neotyphodium species, endophytic fungi associated with cool-season grasses, enhance host fitness and stress tolerance, but also produce biologically active alkaloids including ergot alkaloids associated with fescue toxicosis in grazing animals. One approach to reduce fescue toxicosis is to manipulate genes in the ergot alkaloid pathway. The gene, dmaW, encoding the first pathway-specific step in ergot alkaloid biosynthesis, was cloned previously from Claviceps spp. and its function was demonstrated by expression in yeast. Putative homologs have been cloned from Neotyphodium coenophialum (from tall fescue) and Neotyphodium sp. Lp1 (from perennial ryegrass). In order to confirm the function of dmaW in ergot alkaloid production, dmaW in Neotyphodium sp. isolate Lp1 was knocked out by gene replacement. The dmaW knockout mutant produced no detectable ergovaline or simpler ergot alkaloids. Complementation with Claviceps fusiformis dmaW restored ergovaline production. These results confirmed that the cloned endophyte gene was dmaW, and represented the first genetic experiments to show the requirement of dmaW for ergot alkaloid biosynthesis. Neotyphodium coenophialum, endophyte of the grass tall fescue (Lolium arundinaceum) has two homologs of dmaW. Considering the possible field applications in future, the Cre/lox site-specific recombination system was chosen because of the potential to sequentially knock out both homologs and obtain marker-free dmaW mutants of N. coenophialum. One homolog, dmaW-2, was disrupted by marker exchange, and the marker was eliminated by Cre, thus demonstrating the application of Cre/lox system in N. coenophialum to eliminate a marker gene. The dmaW-2 knockout did not eliminate ergovaline production, indicating that the dmaW-1 was probably also active in N. coenophialum. A putative ergot alkaloid biosynthesis gene cluster was identified in Claviceps purpurea and C. fusiformis. C. purpurea and C. fusiformis produce different subsets of ergot alkaloids. Identification of nine common genes between them suggests the possible role of these genes in the early part of the ergot alkaloid biosynthetic pathway
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