Background Oral inhibitors of JAK1 have become promising therapeutic agents for the treatment of ... more Background Oral inhibitors of JAK1 have become promising therapeutic agents for the treatment of inflammatory bowel diseases (IBD); however, concerns have been raised regarding their specificity and safety profiles. Currently, a local therapy based on specific JAK1 siRNA combined with lipid nanoparticle (LNP) technology is under investigation as a safer alternative to JAK inhibitors.The purpose of this study is to explore the inhibition of the JAK1 pathway in the intestinal epithelium mediated by siRNA/LNP technology, using human primary 2D culture. Methods Human primary 2D cultures were generated from colonic 3D organoids of non-IBD donors. The efficiency of JAK1 pathway inhibition was tested in IFN-y stimulated cultures using either filgotinib (a JAK1 inhibitor, used as a control) or the novel human JAK1 siRNA. JAK1 siRNA transfection was performed using Lipofectamine or LNPs. qPCR was performed on a panel of JAK1 target genes to evaluate the efficiency of JAK1 pathway inhibition....
The continuous exposure of the human body’s cells to radiation and genotoxic stresses leads to th... more The continuous exposure of the human body’s cells to radiation and genotoxic stresses leads to the accumulation of DNA lesions. Fortunately, our body has several effective repair mechanisms, among which is nucleotide excision repair (NER), to counteract these lesions. NER includes both global genome repair (GG-NER) and transcription-coupled repair (TC-NER). Deficiencies in the NER pathway underlie the development of several DNA repair diseases, such as xeroderma pigmentosum (XP), Cockayne syndrome (CS), and trichothiodystrophy (TTD). Deficiencies in GG-NER and TC-NER render individuals to become prone to cancer and neurological disorders, respectively. Therefore, NER regulation is of interest in fine-tuning these risks. Distinct signaling cascades including the NFE2L2 (NRF2), AHR, PI3K/AKT1, MAPK, and CSNK2A1 pathways can modulate NER function. In addition, several chemical and biological compounds have proven success in regulating NER’s activity. These modulators, particularly the ...
IV International Symposium on Seed Research in Horticulture, 1989
... TOXICITY IN SEEDS A. Pradet, S. Attucci, X. Gidrol, M. Noubhani, P. Raymond, V. Saint-Ges, B.... more ... TOXICITY IN SEEDS A. Pradet, S. Attucci, X. Gidrol, M. Noubhani, P. Raymond, V. Saint-Ges, B. Mocquot, B. Ricard, and J ... in many other seeds called "group 1"; among them most are of horticultural importance (Cabbage, Radish, Turnip, Lettuce, Sunflower, Flax)(Raymond et al ...
Single cell analysis circumvents the need to average data from large populations by observing eac... more Single cell analysis circumvents the need to average data from large populations by observing each cell individually, thus enabling the analysis of cell-to-cell variability. The ability to work on this scale presents many new opportunities for the life sciences and biomedical applications. Microfluidics has become a tool of choice for such studies and electrowetting on dielectric (EWOD) technology is well adapted for samples with reduced size and biological studies at the single cell level. In the present manuscript, for the first time, we present an integrated and automated system based on EWOD that can process the complete workflow on a single device, from the isolation of a single cell to mRNA purification and gene expression analysis.
We established a gene expression profile resulting from ricin exposure and demonstrated its abili... more We established a gene expression profile resulting from ricin exposure and demonstrated its ability to classify exposed vs. non-exposed mice with a drop of blood using an integrated microfluidic cartridge.
Hevein, a lectin-like protein is the major protein of vacuolar structures called lutoids in the l... more Hevein, a lectin-like protein is the major protein of vacuolar structures called lutoids in the latex of rubber trees. We have shown both by in planta and ex planta studies that hevein is involved in the coagulation of latex by bringing together rubber particles. This polyvalent bridging between hevein and rubber particles is mediated by N-acetyl-D-glucosamine and involves a receptor glycoprotein of 22 kDa, which is localized on the surface of the rubber particles. The proposed role of hevein helps us to understand the mechanism of coagulation of latex and assigns a physiological intracellular function to one of the smallest lectins.
The effect of Cl- and other anions on the tonoplast H+-translocating ATPase (H+-ATPase) from Heve... more The effect of Cl- and other anions on the tonoplast H+-translocating ATPase (H+-ATPase) from Hevea brasiliensis (rubber tree) latex was investigated. Cl- and other anions stimulated the ATPase activity of tightly sealed vesicles prepared from Hevea tonoplast, with the following decreasing order of effectiveness: Cl- greater than Br- greater than SO4(2-) greater than NO3-. As indicated by the changes of the protonmotive potential difference, anion stimulation of tonoplast H+-ATPase was caused in part by the ability of these anions to dissipate the electrical potential. This interpretation assumes not a channelling of these anions against a membrane potential, negative-inside, but a modification of the permeability of these ions through the tonoplast membrane. In addition, Cl- and the other anions stimulated the ATPase activity solubilized from the tonoplast membrane. Consequently, the tonoplast H+-pumping ATPase can be considered as an anion-stimulated enzyme. These results are discu...
Microfluidic bioreactors are expected to impact cell therapy and biopharmaceutical production due... more Microfluidic bioreactors are expected to impact cell therapy and biopharmaceutical production due to their ability to control cellular microenvironments. This work presents a novel approach for continuous cell culture in a microfluidic system. Microcarriers (i.e., microbeads) are used as growth support for anchorage-dependent mammalian cells. This approach eases the manipulation of cells within the system and enables harmless extraction of cells. Moreover, the microbioreactor uses a perfusion function based on the biocompatible integration of a porous membrane to continuously feed the cells. The perfusion rate is optimized through simulations to provide a stable biochemical environment. Thermal management is also addressed to ensure a homogeneous bioreactor temperature. Eventually, incubator-free cell cultures of Drosophila S2 and PC3 cells are achieved over the course of a week using this bioreactor. In future applications, a more efficient alternative to harvesting cells from microcarriers is also anticipated as suggested by our positive results from the microcarrier digestion experiments.
Genomics has revolutionised biological and biomedical research. This revolution was predictable o... more Genomics has revolutionised biological and biomedical research. This revolution was predictable on the basis of its two driving forces: the ever increasing availability of genome sequences and the development of new technology able to exploit them. Up until now, technical limitations meant that molecular biology could only analyse one or two parameters per experiment, providing relatively little information compared with
Imaging, Manipulation, and Analysis of Biomolecules, Cells, and Tissues XII, 2014
ABSTRACT Innovative imaging methods are continuously developed to investigate the function of bio... more ABSTRACT Innovative imaging methods are continuously developed to investigate the function of biological systems at the microscopic scale. As an alternative to advanced cell microscopy techniques, we are developing lensfree video microscopy that opens new ranges of capabilities, in particular at the mesoscopic level. Lensfree video microscopy allows the observation of a cell culture in an incubator over a very large field of view (24 mm2) for extended periods of time. As a result, a large set of comprehensive data can be gathered with strong statistics, both in space and time. Video lensfree microscopy can capture images of cells cultured in various physical environments. We emphasize on two different case studies: the quantitative analysis of the spontaneous network formation of HUVEC endothelial cells, and by coupling lensfree microscopy with 3D cell culture in the study of epithelial tissue morphogenesis. In summary, we demonstrate that lensfree video microscopy is a powerful tool to conduct cell assays in 2D and 3D culture experiments. The applications are in the realms of fundamental biology, tissue regeneration, drug development and toxicology studies.
Background Oral inhibitors of JAK1 have become promising therapeutic agents for the treatment of ... more Background Oral inhibitors of JAK1 have become promising therapeutic agents for the treatment of inflammatory bowel diseases (IBD); however, concerns have been raised regarding their specificity and safety profiles. Currently, a local therapy based on specific JAK1 siRNA combined with lipid nanoparticle (LNP) technology is under investigation as a safer alternative to JAK inhibitors.The purpose of this study is to explore the inhibition of the JAK1 pathway in the intestinal epithelium mediated by siRNA/LNP technology, using human primary 2D culture. Methods Human primary 2D cultures were generated from colonic 3D organoids of non-IBD donors. The efficiency of JAK1 pathway inhibition was tested in IFN-y stimulated cultures using either filgotinib (a JAK1 inhibitor, used as a control) or the novel human JAK1 siRNA. JAK1 siRNA transfection was performed using Lipofectamine or LNPs. qPCR was performed on a panel of JAK1 target genes to evaluate the efficiency of JAK1 pathway inhibition....
The continuous exposure of the human body’s cells to radiation and genotoxic stresses leads to th... more The continuous exposure of the human body’s cells to radiation and genotoxic stresses leads to the accumulation of DNA lesions. Fortunately, our body has several effective repair mechanisms, among which is nucleotide excision repair (NER), to counteract these lesions. NER includes both global genome repair (GG-NER) and transcription-coupled repair (TC-NER). Deficiencies in the NER pathway underlie the development of several DNA repair diseases, such as xeroderma pigmentosum (XP), Cockayne syndrome (CS), and trichothiodystrophy (TTD). Deficiencies in GG-NER and TC-NER render individuals to become prone to cancer and neurological disorders, respectively. Therefore, NER regulation is of interest in fine-tuning these risks. Distinct signaling cascades including the NFE2L2 (NRF2), AHR, PI3K/AKT1, MAPK, and CSNK2A1 pathways can modulate NER function. In addition, several chemical and biological compounds have proven success in regulating NER’s activity. These modulators, particularly the ...
IV International Symposium on Seed Research in Horticulture, 1989
... TOXICITY IN SEEDS A. Pradet, S. Attucci, X. Gidrol, M. Noubhani, P. Raymond, V. Saint-Ges, B.... more ... TOXICITY IN SEEDS A. Pradet, S. Attucci, X. Gidrol, M. Noubhani, P. Raymond, V. Saint-Ges, B. Mocquot, B. Ricard, and J ... in many other seeds called "group 1"; among them most are of horticultural importance (Cabbage, Radish, Turnip, Lettuce, Sunflower, Flax)(Raymond et al ...
Single cell analysis circumvents the need to average data from large populations by observing eac... more Single cell analysis circumvents the need to average data from large populations by observing each cell individually, thus enabling the analysis of cell-to-cell variability. The ability to work on this scale presents many new opportunities for the life sciences and biomedical applications. Microfluidics has become a tool of choice for such studies and electrowetting on dielectric (EWOD) technology is well adapted for samples with reduced size and biological studies at the single cell level. In the present manuscript, for the first time, we present an integrated and automated system based on EWOD that can process the complete workflow on a single device, from the isolation of a single cell to mRNA purification and gene expression analysis.
We established a gene expression profile resulting from ricin exposure and demonstrated its abili... more We established a gene expression profile resulting from ricin exposure and demonstrated its ability to classify exposed vs. non-exposed mice with a drop of blood using an integrated microfluidic cartridge.
Hevein, a lectin-like protein is the major protein of vacuolar structures called lutoids in the l... more Hevein, a lectin-like protein is the major protein of vacuolar structures called lutoids in the latex of rubber trees. We have shown both by in planta and ex planta studies that hevein is involved in the coagulation of latex by bringing together rubber particles. This polyvalent bridging between hevein and rubber particles is mediated by N-acetyl-D-glucosamine and involves a receptor glycoprotein of 22 kDa, which is localized on the surface of the rubber particles. The proposed role of hevein helps us to understand the mechanism of coagulation of latex and assigns a physiological intracellular function to one of the smallest lectins.
The effect of Cl- and other anions on the tonoplast H+-translocating ATPase (H+-ATPase) from Heve... more The effect of Cl- and other anions on the tonoplast H+-translocating ATPase (H+-ATPase) from Hevea brasiliensis (rubber tree) latex was investigated. Cl- and other anions stimulated the ATPase activity of tightly sealed vesicles prepared from Hevea tonoplast, with the following decreasing order of effectiveness: Cl- greater than Br- greater than SO4(2-) greater than NO3-. As indicated by the changes of the protonmotive potential difference, anion stimulation of tonoplast H+-ATPase was caused in part by the ability of these anions to dissipate the electrical potential. This interpretation assumes not a channelling of these anions against a membrane potential, negative-inside, but a modification of the permeability of these ions through the tonoplast membrane. In addition, Cl- and the other anions stimulated the ATPase activity solubilized from the tonoplast membrane. Consequently, the tonoplast H+-pumping ATPase can be considered as an anion-stimulated enzyme. These results are discu...
Microfluidic bioreactors are expected to impact cell therapy and biopharmaceutical production due... more Microfluidic bioreactors are expected to impact cell therapy and biopharmaceutical production due to their ability to control cellular microenvironments. This work presents a novel approach for continuous cell culture in a microfluidic system. Microcarriers (i.e., microbeads) are used as growth support for anchorage-dependent mammalian cells. This approach eases the manipulation of cells within the system and enables harmless extraction of cells. Moreover, the microbioreactor uses a perfusion function based on the biocompatible integration of a porous membrane to continuously feed the cells. The perfusion rate is optimized through simulations to provide a stable biochemical environment. Thermal management is also addressed to ensure a homogeneous bioreactor temperature. Eventually, incubator-free cell cultures of Drosophila S2 and PC3 cells are achieved over the course of a week using this bioreactor. In future applications, a more efficient alternative to harvesting cells from microcarriers is also anticipated as suggested by our positive results from the microcarrier digestion experiments.
Genomics has revolutionised biological and biomedical research. This revolution was predictable o... more Genomics has revolutionised biological and biomedical research. This revolution was predictable on the basis of its two driving forces: the ever increasing availability of genome sequences and the development of new technology able to exploit them. Up until now, technical limitations meant that molecular biology could only analyse one or two parameters per experiment, providing relatively little information compared with
Imaging, Manipulation, and Analysis of Biomolecules, Cells, and Tissues XII, 2014
ABSTRACT Innovative imaging methods are continuously developed to investigate the function of bio... more ABSTRACT Innovative imaging methods are continuously developed to investigate the function of biological systems at the microscopic scale. As an alternative to advanced cell microscopy techniques, we are developing lensfree video microscopy that opens new ranges of capabilities, in particular at the mesoscopic level. Lensfree video microscopy allows the observation of a cell culture in an incubator over a very large field of view (24 mm2) for extended periods of time. As a result, a large set of comprehensive data can be gathered with strong statistics, both in space and time. Video lensfree microscopy can capture images of cells cultured in various physical environments. We emphasize on two different case studies: the quantitative analysis of the spontaneous network formation of HUVEC endothelial cells, and by coupling lensfree microscopy with 3D cell culture in the study of epithelial tissue morphogenesis. In summary, we demonstrate that lensfree video microscopy is a powerful tool to conduct cell assays in 2D and 3D culture experiments. The applications are in the realms of fundamental biology, tissue regeneration, drug development and toxicology studies.
Uploads