The global impact of human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AID... more The global impact of human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS) is increasing and traditional preventative 'safe sex' strategies do not seem to be slowing the spread of this virus. With an efficacious vaccine at least a decade away, the only strategy to avoid the ever-increasing cost of highly active antiretroviral therapy (HAART) is to develop new methods that prevent virus transmission. Microbicides are topicallyapplied molecules that disrupt the HIV cycle and block infection. This review discusses the current state of the art in microbicide development, looking at the most clinically advanced microbicides and those at earlier development stages based on their mechanisms of action. The socioeconomic impact of microbicide use is also considered, as this will determine whether microbicides are taken up and used consistently by the target population.
ObjectiveTo assess adaptive immunity to SARS-CoV-2 in anti-CD20 treated individuals with mRNA vac... more ObjectiveTo assess adaptive immunity to SARS-CoV-2 in anti-CD20 treated individuals with mRNA vaccination.BackgroundAnti-CD20 therapies attenuate humoral responses to vaccines. However, their effect on T cell responses is less clear. We examined B and T cell responses following COVID-19 vaccination in patients receiving anti-CD20 therapy for multiple sclerosis (MS) and other autoimmune inflammatory neurologic diseases (AINDs, e.g., autoimmune encephalitis, stiff person syndrome, etc.).Design/MethodsMS and AIND patients on anti-CD20 therapies were prospectively enrolled for longitudinal analysis of antibody and T cell responses after a 3rd COVID-19 vaccination. Serum antibodies against the receptor-binding domain of the S1 spike protein (RBD-S1 IgG), neutralizing antibodies, and SARS-CoV-2 CD8 T cell responses, using activation-induced markers (AIM) and INF-γ release assays (EUROIMMUN, Germany), were measured at various time points including pre-vaccination, post initial vaccination ...
Cancer patients show increased morbidity with COVID-19 and need effective immunization strategies... more Cancer patients show increased morbidity with COVID-19 and need effective immunization strategies. We demonstrate that a 3rd dose of COVID-19 vaccine leads to seroconversion in 57% of patients that were seronegative after primary vaccination. The immune response is durable as assessed by anti-S antibody titers, T-cell activity and neutralization activity against wild-type SARS-CoV2 and BA1.1.529 at 6 months of follow up. A subset of severely immunocompromised hematologic malignancy patients were unable to mount adequate immune response after the 3rd dose and were treated with a 4th dose in a prospective clinical trial which led to adequate immune-boost in 67% of patients. Low baseline IgM levels and CD19 counts were associated with inadequate seroconversion. Booster doses induced limited neutralization activity against the Omicron variant. These results indicate that vaccine booster-induced immunity is durable in cancer patients and additional doses can further stimulate immunity in...
In recent years, there have been increasing numbers of infectious disease outbreaks that spread r... more In recent years, there have been increasing numbers of infectious disease outbreaks that spread rapidly to population centers resulting from global travel, population vulnerabilities, environmental factors, and ecological disasters such as floods and earthquakes. Some examples of the recent outbreaks are the Ebola epidemic in West Africa, Middle East respiratory syndrome coronavirus (MERS-Co) in the Middle East, and the Zika outbreak through the Americas. We have created a generic protocol for detection of pathogen RNA and/or DNA using loop-mediated isothermal amplification (LAMP) and reverse dot-blot for detection (RDB) and processed automatically in a microfluidic device. In particular, we describe how a microfluidic assay to detect HIV viral RNA was converted to detect Zika virus (ZIKV) RNA. We first optimized the RT-LAMP assay to detect ZIKV RNA using a benchtop isothermal amplification device. Then we implemented the assay in a microfluidic device that will allow analyzing 24 s...
Background:Cancer patients show increased morbidity with COVID-19 and need effective immunization... more Background:Cancer patients show increased morbidity with COVID-19 and need effective immunization strategies. Many healthcare regulatory agencies recommend administering ‘booster’ doses of COVID-19 vaccines beyond the standard two-dose series, for this group of patients. Therefore, studying the efficacy of these additional vaccine doses against SARS-CoV-2 and variants of concern is of utmost importance in this immunocompromised patient populationMethods:We conducted a prospective single arm clinical trial enrolling patients with cancer that had received two doses of mRNA or one dose of AD26.CoV2.S vaccine and administered a third dose of mRNA vaccine. We further enrolled patients that had no or low responses to three mRNA COVID vaccines and assessed the efficacy of a fourth dose of mRNA vaccine. Efficacy was assessed by changes in anti-spike antibody, T-cell activity, and neutralization activity, which were again assessed at baseline and 4 weeks.Results:We demonstrate that a third d...
Human cytomegalovirus (HCMV) is the major viral cause of birth defects, a serious problem in immu... more Human cytomegalovirus (HCMV) is the major viral cause of birth defects, a serious problem in immunocompromised individuals, and has been associated with atherosclerosis. Previous studies have shown that the induction of autophagy can inhibit the replication of several different types of DNA and RNA viruses. The goal of the work presented here was to determine whether constitutive activation of autophagy would also block replication of HCMV. Most prior studies have used agents that induce autophagy via inhibition of the mTOR pathway. However, since HCMV infection alters the sensitivity of mTOR kinase-containing complexes to inhibitors, we sought an alternative method of inducing autophagy. We chose to use trehalose, a nontoxic naturally occurring disaccharide that is found in plants, insects, microorganisms, and invertebrates, but not in mammals, and induces autophagy by an mTOR-independent mechanism. Given the many different cell targets of HCMV, we proceeded to determine whether tr...
European Union (EU) agricultural policy has been developed in the pursuit of laudable goals such ... more European Union (EU) agricultural policy has been developed in the pursuit of laudable goals such as a competitive economy and regulatory harmony across the union. However, what has emerged is a fragmented, contradictory, and unworkable legislative framework that threatens economic disaster. In this review, we present case studies highlighting differences in the regulations applied to foods grown in EU countries and identical imported products, which show that the EU is undermining its own competitiveness in the agricultural sector, damaging both the EU and its humanitarian activities in the developing world. We recommend the adoption of rational, science-based principles for the harmonization of agricultural policies to prevent economic decline and lower standards of living across the continent.
Maize (Zea mays), the world's third most important cereal crop, was the first plant developed int... more Maize (Zea mays), the world's third most important cereal crop, was the first plant developed into a commercial platform for molecular pharming in the field. Although there are now many different plant-based platforms, including leafy crops, fruit and vegetable crops, other cereals, aquatic plants, algae and systems based on plant viruses and cultured plant cells, maize still demonstrates the unique combination of advantages that made it the first choice for many researchers. In this review, we look at the drivers for using maize as a platform for large-scale production of recombinant pharmaceutical proteins. As well as discussing the technical merits and limitations of the species, we explore the regulatory burden that plant-made pharmaceuticals carry, and use scientific data to expose the misconceptions surrounding the perceived 'risks' of using maize as a pharmaceutical crop.
Multigene transformation (MGT) is becoming routine in plant biotechnology as researchers seek to ... more Multigene transformation (MGT) is becoming routine in plant biotechnology as researchers seek to generate more complex and ambitious phenotypes in transgenic plants. Every nuclear transgene requires its own promoter, so when coordinated expression is required, the introduction of multiple genes leads inevitably to two opposing strategies: different promoters may be used for each transgene, or the same promoter may be used over and over again. In the former case, there may be a shortage of different promoters with matching activities, but repetitious promoter use may in some cases have a negative impact on transgene stability and expression. Using illustrative case studies, we discuss promoter deployment strategies in transgenic plants that increase the likelihood of successful and stable multiple transgene expression.
The do-it-yourself patent search is a useful alternative to professional patent analysis particul... more The do-it-yourself patent search is a useful alternative to professional patent analysis particularly in the context of publicly funded projects where funds for IP activities may be limited. As a case study, we analysed patents related to the engineering of terpenoid indole alkaloid (TIA) metabolism in plants. We developed a focused search strategy to remove redundancy and reduce the workload without missing important and relevant patents. This resulted in the identification of approximately 50 key patents associated with TIA metabolic engineering in plants, which could form the basis of a more detailed freedom-to-operate analysis. The structural elements of this search strategy could easily be transferred to other contexts, making it a useful generic model for publicly funded research projects a .
On July 13, 2010, the European Commission (EC) officially proposed to give member states the free... more On July 13, 2010, the European Commission (EC) officially proposed to give member states the freedom to veto the cultivation of genetically modified (GM) crops on their own territory without having to provide any scientific evidence relating to new risks 1. The objective of ...
The global impact of human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AID... more The global impact of human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS) is increasing and traditional preventative 'safe sex' strategies do not seem to be slowing the spread of this virus. With an efficacious vaccine at least a decade away, the only strategy to avoid the ever-increasing cost of highly active antiretroviral therapy (HAART) is to develop new methods that prevent virus transmission. Microbicides are topicallyapplied molecules that disrupt the HIV cycle and block infection. This review discusses the current state of the art in microbicide development, looking at the most clinically advanced microbicides and those at earlier development stages based on their mechanisms of action. The socioeconomic impact of microbicide use is also considered, as this will determine whether microbicides are taken up and used consistently by the target population.
Cereal seeds are versatile platforms for the production of recombinant proteins because they prov... more Cereal seeds are versatile platforms for the production of recombinant proteins because they provide a stable environment for protein accumulation. Endogenous seed storage proteins, however, include several prolamin-type polypeptides that aggregate and crosslink via intermolecular disulfide bridges, which could potentially interact with multimeric recombinant proteins such as antibodies, which assemble in the same manner. We investigated this possibility by sequentially extracting a human antibody expressed in maize endosperm, followed by precipitation in vitro with zein. We provide evidence that a significant proportion of the antibody pool interacts with zein and therefore cannot be extracted using non-reducing buffers. Immunolocalization experiments demonstrated that antibodies targeted for secretion were instead retained within zein bodies because of such covalent interactions. Our findings suggest that the production of soluble recombinant antibodies in maize could be enhanced by eliminating or minimizing interactions with endogenous storage proteins.
Maize (also known as corn) is a domesticated cereal grain that has been grown as food and animal ... more Maize (also known as corn) is a domesticated cereal grain that has been grown as food and animal feed for tens of thousands of years. It is currently the most widely grown crop in the world, and is used not only for food/feed but also to produce ethanol, industrial starches and oils. Maize is now at the beginning of a new agricultural revolution, where the grains are used as factories to synthesize high-value molecules. In this article we look at the diversity of high-value products from maize, recent technological advances in the field and the emerging regulatory framework that governs how transgenic maize plants and their products are grown, used and traded.
The eight Millennium Development Goals (MDGs) are international development targets for the year ... more The eight Millennium Development Goals (MDGs) are international development targets for the year 2015 that aim to achieve relative improvements in the standards of health, socioeconomic status and education in the world's poorest countries. Many of the challenges addressed by the MDGs reflect the direct or indirect consequences of subsistence agriculture in the developing world, and hence, plant biotechnology has an important role to play in helping to achieve MDG targets. In this opinion article, we discuss each of the MDGs in turn, provide examples to show how plant biotechnology may be able to accelerate progress towards the stated MDG objectives, and offer our opinion on the likelihood of such technology being implemented. In combination with other strategies, plant biotechnology can make a contribution towards sustainable development in the future although the extent to which progress can be made in today's political climate depends on how we deal with current barrier...
The production of recombinant proteins in seeds is achieved by driving transgene expression using... more The production of recombinant proteins in seeds is achieved by driving transgene expression using promoters and protein targeting sequences derived from genes encoding abundant seed storage proteins. This approach is advantageous because high yields, stability and containment are conferred by the accumulation of recombinant proteins in specialized storage compartments such as protein bodies and protein storage vacuoles. Seeds are particularly suitable for the production of pharmaceutical proteins in developing country settings because they reduce the costs of production and distribution by avoiding the need for fermenter-based production capacity and a cold chain for storage and distribution, thus increasing access to critical medicines for the poor in rural areas. Seeds are also ideal for the production of oral vaccine antigens, because encapsulation within the seed provides protection that prolongs exposure to the gastric immune system and thus increases the potency of the immune response. In this review we discuss the current state of the art in seed-based molecular pharming and the future potential of production platforms based on seeds.
The global impact of human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AID... more The global impact of human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS) is increasing and traditional preventative 'safe sex' strategies do not seem to be slowing the spread of this virus. With an efficacious vaccine at least a decade away, the only strategy to avoid the ever-increasing cost of highly active antiretroviral therapy (HAART) is to develop new methods that prevent virus transmission. Microbicides are topicallyapplied molecules that disrupt the HIV cycle and block infection. This review discusses the current state of the art in microbicide development, looking at the most clinically advanced microbicides and those at earlier development stages based on their mechanisms of action. The socioeconomic impact of microbicide use is also considered, as this will determine whether microbicides are taken up and used consistently by the target population.
ObjectiveTo assess adaptive immunity to SARS-CoV-2 in anti-CD20 treated individuals with mRNA vac... more ObjectiveTo assess adaptive immunity to SARS-CoV-2 in anti-CD20 treated individuals with mRNA vaccination.BackgroundAnti-CD20 therapies attenuate humoral responses to vaccines. However, their effect on T cell responses is less clear. We examined B and T cell responses following COVID-19 vaccination in patients receiving anti-CD20 therapy for multiple sclerosis (MS) and other autoimmune inflammatory neurologic diseases (AINDs, e.g., autoimmune encephalitis, stiff person syndrome, etc.).Design/MethodsMS and AIND patients on anti-CD20 therapies were prospectively enrolled for longitudinal analysis of antibody and T cell responses after a 3rd COVID-19 vaccination. Serum antibodies against the receptor-binding domain of the S1 spike protein (RBD-S1 IgG), neutralizing antibodies, and SARS-CoV-2 CD8 T cell responses, using activation-induced markers (AIM) and INF-γ release assays (EUROIMMUN, Germany), were measured at various time points including pre-vaccination, post initial vaccination ...
Cancer patients show increased morbidity with COVID-19 and need effective immunization strategies... more Cancer patients show increased morbidity with COVID-19 and need effective immunization strategies. We demonstrate that a 3rd dose of COVID-19 vaccine leads to seroconversion in 57% of patients that were seronegative after primary vaccination. The immune response is durable as assessed by anti-S antibody titers, T-cell activity and neutralization activity against wild-type SARS-CoV2 and BA1.1.529 at 6 months of follow up. A subset of severely immunocompromised hematologic malignancy patients were unable to mount adequate immune response after the 3rd dose and were treated with a 4th dose in a prospective clinical trial which led to adequate immune-boost in 67% of patients. Low baseline IgM levels and CD19 counts were associated with inadequate seroconversion. Booster doses induced limited neutralization activity against the Omicron variant. These results indicate that vaccine booster-induced immunity is durable in cancer patients and additional doses can further stimulate immunity in...
In recent years, there have been increasing numbers of infectious disease outbreaks that spread r... more In recent years, there have been increasing numbers of infectious disease outbreaks that spread rapidly to population centers resulting from global travel, population vulnerabilities, environmental factors, and ecological disasters such as floods and earthquakes. Some examples of the recent outbreaks are the Ebola epidemic in West Africa, Middle East respiratory syndrome coronavirus (MERS-Co) in the Middle East, and the Zika outbreak through the Americas. We have created a generic protocol for detection of pathogen RNA and/or DNA using loop-mediated isothermal amplification (LAMP) and reverse dot-blot for detection (RDB) and processed automatically in a microfluidic device. In particular, we describe how a microfluidic assay to detect HIV viral RNA was converted to detect Zika virus (ZIKV) RNA. We first optimized the RT-LAMP assay to detect ZIKV RNA using a benchtop isothermal amplification device. Then we implemented the assay in a microfluidic device that will allow analyzing 24 s...
Background:Cancer patients show increased morbidity with COVID-19 and need effective immunization... more Background:Cancer patients show increased morbidity with COVID-19 and need effective immunization strategies. Many healthcare regulatory agencies recommend administering ‘booster’ doses of COVID-19 vaccines beyond the standard two-dose series, for this group of patients. Therefore, studying the efficacy of these additional vaccine doses against SARS-CoV-2 and variants of concern is of utmost importance in this immunocompromised patient populationMethods:We conducted a prospective single arm clinical trial enrolling patients with cancer that had received two doses of mRNA or one dose of AD26.CoV2.S vaccine and administered a third dose of mRNA vaccine. We further enrolled patients that had no or low responses to three mRNA COVID vaccines and assessed the efficacy of a fourth dose of mRNA vaccine. Efficacy was assessed by changes in anti-spike antibody, T-cell activity, and neutralization activity, which were again assessed at baseline and 4 weeks.Results:We demonstrate that a third d...
Human cytomegalovirus (HCMV) is the major viral cause of birth defects, a serious problem in immu... more Human cytomegalovirus (HCMV) is the major viral cause of birth defects, a serious problem in immunocompromised individuals, and has been associated with atherosclerosis. Previous studies have shown that the induction of autophagy can inhibit the replication of several different types of DNA and RNA viruses. The goal of the work presented here was to determine whether constitutive activation of autophagy would also block replication of HCMV. Most prior studies have used agents that induce autophagy via inhibition of the mTOR pathway. However, since HCMV infection alters the sensitivity of mTOR kinase-containing complexes to inhibitors, we sought an alternative method of inducing autophagy. We chose to use trehalose, a nontoxic naturally occurring disaccharide that is found in plants, insects, microorganisms, and invertebrates, but not in mammals, and induces autophagy by an mTOR-independent mechanism. Given the many different cell targets of HCMV, we proceeded to determine whether tr...
European Union (EU) agricultural policy has been developed in the pursuit of laudable goals such ... more European Union (EU) agricultural policy has been developed in the pursuit of laudable goals such as a competitive economy and regulatory harmony across the union. However, what has emerged is a fragmented, contradictory, and unworkable legislative framework that threatens economic disaster. In this review, we present case studies highlighting differences in the regulations applied to foods grown in EU countries and identical imported products, which show that the EU is undermining its own competitiveness in the agricultural sector, damaging both the EU and its humanitarian activities in the developing world. We recommend the adoption of rational, science-based principles for the harmonization of agricultural policies to prevent economic decline and lower standards of living across the continent.
Maize (Zea mays), the world's third most important cereal crop, was the first plant developed int... more Maize (Zea mays), the world's third most important cereal crop, was the first plant developed into a commercial platform for molecular pharming in the field. Although there are now many different plant-based platforms, including leafy crops, fruit and vegetable crops, other cereals, aquatic plants, algae and systems based on plant viruses and cultured plant cells, maize still demonstrates the unique combination of advantages that made it the first choice for many researchers. In this review, we look at the drivers for using maize as a platform for large-scale production of recombinant pharmaceutical proteins. As well as discussing the technical merits and limitations of the species, we explore the regulatory burden that plant-made pharmaceuticals carry, and use scientific data to expose the misconceptions surrounding the perceived 'risks' of using maize as a pharmaceutical crop.
Multigene transformation (MGT) is becoming routine in plant biotechnology as researchers seek to ... more Multigene transformation (MGT) is becoming routine in plant biotechnology as researchers seek to generate more complex and ambitious phenotypes in transgenic plants. Every nuclear transgene requires its own promoter, so when coordinated expression is required, the introduction of multiple genes leads inevitably to two opposing strategies: different promoters may be used for each transgene, or the same promoter may be used over and over again. In the former case, there may be a shortage of different promoters with matching activities, but repetitious promoter use may in some cases have a negative impact on transgene stability and expression. Using illustrative case studies, we discuss promoter deployment strategies in transgenic plants that increase the likelihood of successful and stable multiple transgene expression.
The do-it-yourself patent search is a useful alternative to professional patent analysis particul... more The do-it-yourself patent search is a useful alternative to professional patent analysis particularly in the context of publicly funded projects where funds for IP activities may be limited. As a case study, we analysed patents related to the engineering of terpenoid indole alkaloid (TIA) metabolism in plants. We developed a focused search strategy to remove redundancy and reduce the workload without missing important and relevant patents. This resulted in the identification of approximately 50 key patents associated with TIA metabolic engineering in plants, which could form the basis of a more detailed freedom-to-operate analysis. The structural elements of this search strategy could easily be transferred to other contexts, making it a useful generic model for publicly funded research projects a .
On July 13, 2010, the European Commission (EC) officially proposed to give member states the free... more On July 13, 2010, the European Commission (EC) officially proposed to give member states the freedom to veto the cultivation of genetically modified (GM) crops on their own territory without having to provide any scientific evidence relating to new risks 1. The objective of ...
The global impact of human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AID... more The global impact of human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS) is increasing and traditional preventative 'safe sex' strategies do not seem to be slowing the spread of this virus. With an efficacious vaccine at least a decade away, the only strategy to avoid the ever-increasing cost of highly active antiretroviral therapy (HAART) is to develop new methods that prevent virus transmission. Microbicides are topicallyapplied molecules that disrupt the HIV cycle and block infection. This review discusses the current state of the art in microbicide development, looking at the most clinically advanced microbicides and those at earlier development stages based on their mechanisms of action. The socioeconomic impact of microbicide use is also considered, as this will determine whether microbicides are taken up and used consistently by the target population.
Cereal seeds are versatile platforms for the production of recombinant proteins because they prov... more Cereal seeds are versatile platforms for the production of recombinant proteins because they provide a stable environment for protein accumulation. Endogenous seed storage proteins, however, include several prolamin-type polypeptides that aggregate and crosslink via intermolecular disulfide bridges, which could potentially interact with multimeric recombinant proteins such as antibodies, which assemble in the same manner. We investigated this possibility by sequentially extracting a human antibody expressed in maize endosperm, followed by precipitation in vitro with zein. We provide evidence that a significant proportion of the antibody pool interacts with zein and therefore cannot be extracted using non-reducing buffers. Immunolocalization experiments demonstrated that antibodies targeted for secretion were instead retained within zein bodies because of such covalent interactions. Our findings suggest that the production of soluble recombinant antibodies in maize could be enhanced by eliminating or minimizing interactions with endogenous storage proteins.
Maize (also known as corn) is a domesticated cereal grain that has been grown as food and animal ... more Maize (also known as corn) is a domesticated cereal grain that has been grown as food and animal feed for tens of thousands of years. It is currently the most widely grown crop in the world, and is used not only for food/feed but also to produce ethanol, industrial starches and oils. Maize is now at the beginning of a new agricultural revolution, where the grains are used as factories to synthesize high-value molecules. In this article we look at the diversity of high-value products from maize, recent technological advances in the field and the emerging regulatory framework that governs how transgenic maize plants and their products are grown, used and traded.
The eight Millennium Development Goals (MDGs) are international development targets for the year ... more The eight Millennium Development Goals (MDGs) are international development targets for the year 2015 that aim to achieve relative improvements in the standards of health, socioeconomic status and education in the world's poorest countries. Many of the challenges addressed by the MDGs reflect the direct or indirect consequences of subsistence agriculture in the developing world, and hence, plant biotechnology has an important role to play in helping to achieve MDG targets. In this opinion article, we discuss each of the MDGs in turn, provide examples to show how plant biotechnology may be able to accelerate progress towards the stated MDG objectives, and offer our opinion on the likelihood of such technology being implemented. In combination with other strategies, plant biotechnology can make a contribution towards sustainable development in the future although the extent to which progress can be made in today's political climate depends on how we deal with current barrier...
The production of recombinant proteins in seeds is achieved by driving transgene expression using... more The production of recombinant proteins in seeds is achieved by driving transgene expression using promoters and protein targeting sequences derived from genes encoding abundant seed storage proteins. This approach is advantageous because high yields, stability and containment are conferred by the accumulation of recombinant proteins in specialized storage compartments such as protein bodies and protein storage vacuoles. Seeds are particularly suitable for the production of pharmaceutical proteins in developing country settings because they reduce the costs of production and distribution by avoiding the need for fermenter-based production capacity and a cold chain for storage and distribution, thus increasing access to critical medicines for the poor in rural areas. Seeds are also ideal for the production of oral vaccine antigens, because encapsulation within the seed provides protection that prolongs exposure to the gastric immune system and thus increases the potency of the immune response. In this review we discuss the current state of the art in seed-based molecular pharming and the future potential of production platforms based on seeds.
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Papers by Maite Sabalza