Project: “Plant-made subunit vaccine against pneumonic and bubonic plague”
Place of work: CIDV- Biodesign A at Arizona State University, Tempe, Arizona, U.S.A. (2003 – present).
Position: Postdoctoral Research Associate
The goal of this project was to express Yersinia pestis antigens in tomato to develop an oral plant-derived plague vaccine. We successfully obtained transgenic tomato expressing high levels of the fusion protein F1-V (F1 and V are the two most immunogenic antigens from Y. pestis). The immunogenicity of the plant-derived plague vaccine was demonstrated in animal trials. The results obtained were presented in national and international conferences and published (Alvarez et al., 2004; Alvarez et al., 2006).
Dr. Alvarez designed and pursued all the experiments of this project including plasmid constructs, tomato transformation, screening and selection of the transgenic plants and animal trials to test the tomato-derived plague vaccine. Dr. Alvarez directed the undergraduate students that collaborated with this project.
Project: “Reversion of f1-v gene silencing induced by transient and stable expression of TBSV-P19 in tomato”
Place of work: CIDV- Biodesign A at Arizona State University, Tempe, Arizona, U.S.A. (2003 – present).
Position: Postdoctoral Research Associate
The aim of this project was to restore the f1-v gene expression in silenced tomato plants through the stable expression of the viral suppressor of gene silencing, P19, driven by a constitutive promoter as well as in an ethanol inducible promoter. Plants with the highest P19 protein levels correlated with the highest F1-V protein accumulation in transient and stable. These results confirmed the potential exploitation of P19 to substantially increase the expression of value-added proteins in plants (Alvarez et al., manuscript recently submitted for publication).
Dr. Alvarez designed and pursued all the experiments of this project including tomato transformation, screening and selection of the transgenic plants.
Place of work: CIDV- Biodesign A at Arizona State University, Tempe, Arizona, U.S.A. (2003 – present).
Position: Postdoctoral Research Associate
The goal of this project was to express Yersinia pestis antigens in tomato to develop an oral plant-derived plague vaccine. We successfully obtained transgenic tomato expressing high levels of the fusion protein F1-V (F1 and V are the two most immunogenic antigens from Y. pestis). The immunogenicity of the plant-derived plague vaccine was demonstrated in animal trials. The results obtained were presented in national and international conferences and published (Alvarez et al., 2004; Alvarez et al., 2006).
Dr. Alvarez designed and pursued all the experiments of this project including plasmid constructs, tomato transformation, screening and selection of the transgenic plants and animal trials to test the tomato-derived plague vaccine. Dr. Alvarez directed the undergraduate students that collaborated with this project.
Project: “Reversion of f1-v gene silencing induced by transient and stable expression of TBSV-P19 in tomato”
Place of work: CIDV- Biodesign A at Arizona State University, Tempe, Arizona, U.S.A. (2003 – present).
Position: Postdoctoral Research Associate
The aim of this project was to restore the f1-v gene expression in silenced tomato plants through the stable expression of the viral suppressor of gene silencing, P19, driven by a constitutive promoter as well as in an ethanol inducible promoter. Plants with the highest P19 protein levels correlated with the highest F1-V protein accumulation in transient and stable. These results confirmed the potential exploitation of P19 to substantially increase the expression of value-added proteins in plants (Alvarez et al., manuscript recently submitted for publication).
Dr. Alvarez designed and pursued all the experiments of this project including tomato transformation, screening and selection of the transgenic plants.
Project: “Plant-derived vaccines as immuno-contraceptives for animals”
Place of work: CIDV- Biodesign A at Arizona State University, Tempe, Arizona, U.S.A. (2001 – 2002).
Positions: Research Scholar and Fundación Antorchas Fellow
The common brushtail possum is a marsupial native from Australia which was introduced to New Zealand by Europeans to establish a fur industry. They soon escaped into the wild where they have thrived as an invasive species with around 60 million individuals estimated. There have been numerous attempts to eradicate them because of the damage they do to native trees and wildlife, as well as acting as a carrier of bovine tuberculosis. The goal of this project was to develop an oral plant-derived vaccine to be used as immuno-contraceptive specie specific for possum population control. The seven amino acid epitope from ZP3 (zona pellucida glycoprotein 3) was fused to the heat-labile toxin (LT) of enterotoxigenic Escherichia coli and expressed in tomato. The fusion protein was found to assemble into pentamers and had an average expression level of 37.8 μg/g in freeze-dried transgenic tissues. The species-specific nature of this epitope was shown by the inability of antibodies raised against non-target species to detect the LTB fusion protein (Walmsley et al., 2003).
I collaborated on this project doing the molecular characterization of the transgenic tomato plants expressing the fusion protein LTB-ZP3.
Project: “Analysis of dough functionality of flour from transgenic wheat”
Place of work: Superior Technical School for Agronomists (ETSIA), Department of Genetics and Plant Improvement, Polytechnic University of Madrid (UPM), Madrid, SPAIN (2000)
Position: Research Scholar and Fellow of British Council and Fundacion Antorchas (Argentina).
The goal of this project was to determine the new physical properties of the dough made with flour from the different transgenic wheat lines expressing alleles of glutenins associated with better bread-making quality. The rheological properties of flours from five different lines of transgenic wheats that either express or over-express subunits 1Dx5 or 1Ax1 were analyzed by mixograph assays and SDS sedimentation tests. In one of the transgenic lines, the over-expression of subunit 1Dx5 resulted in a 2-fold increase in mixing time, associated with a significant improvement in dough strength, and a lower resistance breakdown, suggesting an important increase in dough quality (Alvarez et. al., 2001).
I designed all the experiments and pursed all the dough analysis with the collaboration of colleagues at the Polytechnic University of Madrid, Spain.
Project (Ph.D Thesis): “Improvement of bread-making and nutritional quality of wheat by genetic engineering”.
Places of work:
1) Center for Biochemical and Photosynthetic Studies (CEFOBI), National University of Rosario, ARGENTINA (1995 – 2000)
2) Cell Biology Department, Institute of Arable Crops Research (IACR), Long Ashton Research Station, Bristol University, Bristol, ENGLAND (2000)
Positions:
1) Graduate Student and Doctoral Fellow from CONICET (Argentinean National Council for Scientific and Technical Research) (1995-2000)
2) Research Scholar and Fellow of British Council/ Fundación Antorchas
The main goal of this project was to improve the bread-making quality of wheat expressing high molecular weight (HMW) subunits of glutenins associated with better dough quality for bread.
Wheat HMW glutenin subunit genes 1Ax1 and 1Dx5 were introduced and either expressed or over-expressed into a commercial wheat cultivar that already expresses five subunits. Six independent transgenic wheat lines were obtained and characterized by SDS-PAGE and Southern-blot analyses. The 1Dx5 gene was over-expressed in two lines without changes in the other endosperm proteins. Two wheat lines expressed the 1Ax1 transgene with associated silencing of the 1Ax2* endogenous subunit. Southern analysis of the four events confirmed transformation and suggested that the transgenes were present in low gene copy number. Silencing of all the HMW glutenin subunits was observed in two different transgenic wheat lines expressing the 1Ax1 subunit transgene and over-expressing the 1Dx5 gene. Transgenes and expression patterns were stably transmitted to the progenies in all the events except one where in some of the segregating T2 seeds the silencing of all HMW glutenin subunits was reverted associated with a drastic loss of transgenes from a high to a low copy number.
This project was part of Dr. Alvarez's Ph.D Thesis; the results obtained were published in different journals (Alvarez et al., 2000; Alvarez et al., 2001a; Alvarez et al.,2001 b).
Place of work: CIDV- Biodesign A at Arizona State University, Tempe, Arizona, U.S.A. (2001 – 2002).
Positions: Research Scholar and Fundación Antorchas Fellow
The common brushtail possum is a marsupial native from Australia which was introduced to New Zealand by Europeans to establish a fur industry. They soon escaped into the wild where they have thrived as an invasive species with around 60 million individuals estimated. There have been numerous attempts to eradicate them because of the damage they do to native trees and wildlife, as well as acting as a carrier of bovine tuberculosis. The goal of this project was to develop an oral plant-derived vaccine to be used as immuno-contraceptive specie specific for possum population control. The seven amino acid epitope from ZP3 (zona pellucida glycoprotein 3) was fused to the heat-labile toxin (LT) of enterotoxigenic Escherichia coli and expressed in tomato. The fusion protein was found to assemble into pentamers and had an average expression level of 37.8 μg/g in freeze-dried transgenic tissues. The species-specific nature of this epitope was shown by the inability of antibodies raised against non-target species to detect the LTB fusion protein (Walmsley et al., 2003).
I collaborated on this project doing the molecular characterization of the transgenic tomato plants expressing the fusion protein LTB-ZP3.
Project: “Analysis of dough functionality of flour from transgenic wheat”
Place of work: Superior Technical School for Agronomists (ETSIA), Department of Genetics and Plant Improvement, Polytechnic University of Madrid (UPM), Madrid, SPAIN (2000)
Position: Research Scholar and Fellow of British Council and Fundacion Antorchas (Argentina).
The goal of this project was to determine the new physical properties of the dough made with flour from the different transgenic wheat lines expressing alleles of glutenins associated with better bread-making quality. The rheological properties of flours from five different lines of transgenic wheats that either express or over-express subunits 1Dx5 or 1Ax1 were analyzed by mixograph assays and SDS sedimentation tests. In one of the transgenic lines, the over-expression of subunit 1Dx5 resulted in a 2-fold increase in mixing time, associated with a significant improvement in dough strength, and a lower resistance breakdown, suggesting an important increase in dough quality (Alvarez et. al., 2001).
I designed all the experiments and pursed all the dough analysis with the collaboration of colleagues at the Polytechnic University of Madrid, Spain.
Project (Ph.D Thesis): “Improvement of bread-making and nutritional quality of wheat by genetic engineering”.
Places of work:
1) Center for Biochemical and Photosynthetic Studies (CEFOBI), National University of Rosario, ARGENTINA (1995 – 2000)
2) Cell Biology Department, Institute of Arable Crops Research (IACR), Long Ashton Research Station, Bristol University, Bristol, ENGLAND (2000)
Positions:
1) Graduate Student and Doctoral Fellow from CONICET (Argentinean National Council for Scientific and Technical Research) (1995-2000)
2) Research Scholar and Fellow of British Council/ Fundación Antorchas
The main goal of this project was to improve the bread-making quality of wheat expressing high molecular weight (HMW) subunits of glutenins associated with better dough quality for bread.
Wheat HMW glutenin subunit genes 1Ax1 and 1Dx5 were introduced and either expressed or over-expressed into a commercial wheat cultivar that already expresses five subunits. Six independent transgenic wheat lines were obtained and characterized by SDS-PAGE and Southern-blot analyses. The 1Dx5 gene was over-expressed in two lines without changes in the other endosperm proteins. Two wheat lines expressed the 1Ax1 transgene with associated silencing of the 1Ax2* endogenous subunit. Southern analysis of the four events confirmed transformation and suggested that the transgenes were present in low gene copy number. Silencing of all the HMW glutenin subunits was observed in two different transgenic wheat lines expressing the 1Ax1 subunit transgene and over-expressing the 1Dx5 gene. Transgenes and expression patterns were stably transmitted to the progenies in all the events except one where in some of the segregating T2 seeds the silencing of all HMW glutenin subunits was reverted associated with a drastic loss of transgenes from a high to a low copy number.
This project was part of Dr. Alvarez's Ph.D Thesis; the results obtained were published in different journals (Alvarez et al., 2000; Alvarez et al., 2001a; Alvarez et al.,2001 b).
Project: “Study of the presence of fimbriae P in bacteria causing urinary infection”.
Place of work: Department of Microbiology, School of Biochemistry, National University of Rosario, ARGENTINA (1992-1993)
Position: Undergraduate Student and Fellow of Rosario State University Foundation.
The long term goal of this project was to study the presence of glitter cells in the urinary sediment as a marker of high urinary infection by Enterobacterias mannose resistant that express fimbriae Pap. A total of 143 Enterobactereaceae strains isolated from patients with urinary infection were classified by biochemical and serological tests. The adhesive ability of the bacteria was determined using the human red cells group A agglutination test. The erythrocytes were suspended in phosphate buffer saline (PBS) either with or without mannose for testing mannose-resistant (MR-HA) or mannose- sensitive (MS-HA) hemagglutination. The number of Escherichia coli strains that expressed mannose-resistant fimbriae was 2-fold higher than the strains with mannose-sensitive fimbriae. There was a correlation between high urinary infections produced by E. coli strains with mannose-resistant fimbriae and presence of cells with special characteristics, glitter cells, in the urinary sediment.
Dr. Alvarez isolated and characterized the bacteria causing urinary infections using biochemical and serological tests. She determined the presence of mannose-resistant fimbriae in the bacteria as well as the glitter cells in the urinary sediment (Alvarez et al., 1994).
Place of work: Department of Microbiology, School of Biochemistry, National University of Rosario, ARGENTINA (1992-1993)
Position: Undergraduate Student and Fellow of Rosario State University Foundation.
The long term goal of this project was to study the presence of glitter cells in the urinary sediment as a marker of high urinary infection by Enterobacterias mannose resistant that express fimbriae Pap. A total of 143 Enterobactereaceae strains isolated from patients with urinary infection were classified by biochemical and serological tests. The adhesive ability of the bacteria was determined using the human red cells group A agglutination test. The erythrocytes were suspended in phosphate buffer saline (PBS) either with or without mannose for testing mannose-resistant (MR-HA) or mannose- sensitive (MS-HA) hemagglutination. The number of Escherichia coli strains that expressed mannose-resistant fimbriae was 2-fold higher than the strains with mannose-sensitive fimbriae. There was a correlation between high urinary infections produced by E. coli strains with mannose-resistant fimbriae and presence of cells with special characteristics, glitter cells, in the urinary sediment.
Dr. Alvarez isolated and characterized the bacteria causing urinary infections using biochemical and serological tests. She determined the presence of mannose-resistant fimbriae in the bacteria as well as the glitter cells in the urinary sediment (Alvarez et al., 1994).
No comments:
Post a Comment