The Experts below are selected from a list of 22197 Experts worldwide ranked by ideXlab platform
Ivana Bilic - One of the best experts on this subject based on the ideXlab platform.
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Cysteine Peptidases, Secreted by Trichomonas gallinae, Are Involved in the Cytopathogenic Effects on a Permanent Chicken Liver Cell Culture
2016Co-Authors: Aziza Amin, Martina Patzl, Evelyn Berger, Michael Hess, Ivana BilicAbstract:Trichomonas gallinae, the aetiological agent of avian trichomonosis, was shown to secrete soluble factors involved in cytopathogenic effect on a permanent chicken Liver (LMH) Cell Culture. The present study focused on the characterization of these molecules. The addition of specific peptidase inhibitors to the Cell-free filtrate partially inhibited the monolayer destruction, which implied the presence of peptidases in the filtrate and their involvement in the cytopathogenic effect. One-dimensional substrate (gelatin) SDS-PAGE confirmed the proteolytic character of the filtrate by demonstrating the proteolytic activity within the molecular weight range from 38 to 110 kDa. In addition, the proteolytic activity was specifically inhibited by addition of TLCK and E-64 cysteine peptidase inhibitors implying their cysteine peptidase nature. Furthermore, variations in the intensity and the number of proteolytic bands were observed between Cell-free filtrates of low and high passages of the same T. gallinae clonal Culture. Two-dimensional substrate gel electrophoresis of concentrated T. gallinae Cell-free filtrate identified at least six proteolytic spots. The mass spectrometric analysis of spots from 2-D gels identified the presence of at least two different Clan CA, family C1, cathepsin L-like cysteine peptidases in the Cell-free filtrate of T. gallinae. In parallel, a PCR approach using degenerated primers based on the conserved amino acid sequence region of cysteine peptidases from Trichomonas vaginalis identified the coding sequences for four different Clan CA, family C1, cathepsin L-like cysteine peptidases. Finally, this is the first report analyzing molecules secreted by T. gallinae an
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cysteine peptidases secreted by trichomonas gallinae are involved in the cytopathogenic effects on a permanent chicken Liver Cell Culture
PLOS ONE, 2012Co-Authors: Aziza Amin, Katharina Nobauer, Martina Patzl, Evelyn Berger, Michael Hess, Ivana BilicAbstract:Trichomonas gallinae, the aetiological agent of avian trichomonosis, was shown to secrete soluble factors involved in cytopathogenic effect on a permanent chicken Liver (LMH) Cell Culture. The present study focused on the characterization of these molecules. The addition of specific peptidase inhibitors to the Cell-free filtrate partially inhibited the monolayer destruction, which implied the presence of peptidases in the filtrate and their involvement in the cytopathogenic effect. One-dimensional substrate (gelatin) SDS-PAGE confirmed the proteolytic character of the filtrate by demonstrating the proteolytic activity within the molecular weight range from 38 to 110 kDa. In addition, the proteolytic activity was specifically inhibited by addition of TLCK and E-64 cysteine peptidase inhibitors implying their cysteine peptidase nature. Furthermore, variations in the intensity and the number of proteolytic bands were observed between Cell-free filtrates of low and high passages of the same T. gallinae clonal Culture. Two-dimensional substrate gel electrophoresis of concentrated T. gallinae Cell-free filtrate identified at least six proteolytic spots. The mass spectrometric analysis of spots from 2-D gels identified the presence of at least two different Clan CA, family C1, cathepsin L-like cysteine peptidases in the Cell-free filtrate of T. gallinae. In parallel, a PCR approach using degenerated primers based on the conserved amino acid sequence region of cysteine peptidases from Trichomonas vaginalis identified the coding sequences for four different Clan CA, family C1, cathepsin L-like cysteine peptidases. Finally, this is the first report analyzing molecules secreted by T. gallinae and demonstrating the ubiquity of peptidases secreted by this protozoon.
Linda G Griffith - One of the best experts on this subject based on the ideXlab platform.
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modeling therapeutic antibody small molecule drug drug interactions using a three dimensional perfusable human Liver coCulture platform
PMC, 2016Co-Authors: Thomas Joseph Long, Hisham K Hamadeh, Patrick A Cosgrove, Robert T Dunn, Donna B Stolz, Cynthia A Afshari, Helen J Mcbride, Linda G GriffithAbstract:Traditional in vitro human Liver Cell Culture models lose key hepatic functions such as metabolic activity during short-term Culture. Advanced three-dimensional (3D) Liver coCulture platforms offer the potential for extended hepatocyte functionality and allow for the study of more complex biologic interactions, which can improve and refine human drug safety evaluations. Here, we use a perfusion flow 3D microreactor platform for the coCulture of cryopreserved primary human hepatocytes and Kupffer Cells to study the regulation of cytochrome P450 3A4 isoform (CYP3A4) activity by chronic interleukin 6 (IL-6)-mediated inflammation over 2 weeks. Hepatocyte Cultures remained stable over 2 weeks, with consistent albumin production and basal IL-6 levels. Direct IL-6 stimulation that mimics an inflammatory state induced a dose-dependent suppression of CYP3A4 activity, an increase in C-reactive protein (CRP) secretion, and a decrease in shed soluble interleukin-6 receptor (IL-6R) levels, indicating expected hepatic IL-6 bioactivity. Tocilizumab, an anti-IL-6R monoclonal antibody used to treat rheumatoid arthritis, has been demonstrated clinically to impact small molecule drug pharmacokinetics by modulating cytochrome P450 enzyme activities, an effect not observed in traditional hepatic Cultures. We have now recapitulated the clinical observation in a 3D bioreactor system. Tocilizumab was shown to desuppress CYP3A4 activity while reducing the CRP concentration after 72 hours in the continued presence of IL-6. This change in CYP3A4 activity decreased the half-life and area under the curve up to the last measurable concentration (AUClast) of the small molecule CYP3A4 substrate simvastatin hydroxy acid, measured before and after tocilizumab treatment. We conclude that next-generation in vitro Liver Culture platforms are well suited for these types of long-term treatment studies and show promise for improved drug safety assessment.
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modeling therapeutic antibody small molecule drug drug interactions using a three dimensional perfusable human Liver coCulture platform
Drug Metabolism and Disposition, 2016Co-Authors: Thomas Joseph Long, Hisham K Hamadeh, Patrick A Cosgrove, Robert T Dunn, Donna B Stolz, Cynthia A Afshari, Helen J Mcbride, Linda G GriffithAbstract:Traditional in vitro human Liver Cell Culture models lose key hepatic functions such as metabolic activity during short-term Culture. Advanced 3D Liver co-Culture platforms offer the potential for extended hepatocyte functionality, allowing for the study of more complex biological interactions that can improve and refine human drug safety evaluation. Here, we utilize a perfusion flow 3D microreactor platform for the co-Culture of cryopreserved primary human hepatocytes and Kupffer Cells to study the regulation of CYP3A4 activity by chronic IL-6-mediated inflammation over two weeks. Hepatocyte Cultures remained stable over two weeks, with consistent albumin production and basal IL-6 levels. Direct IL-6 stimulation that mimics an inflammatory state induced a dose-dependent suppression of CYP3A4 activity, an increase in C-reactive protein (CRP) secretion, and a decrease in shed soluble IL-6R levels, indicating expected hepatic IL-6 bioactivity. Tocilizumab, an anti-IL-6R monoclonal antibody used to treat rheumatoid arthritis, has been demonstrated clinically to impact small molecule drug pharmacokinetics by modulating cytochrome P450 enzyme activities, an effect not observed in traditional hepatic Cultures. We have now recapitulated the clinical observation in a 3D bioreactor system. Tocilizumab was shown to de-suppress CYP3A4 activity while reducing CRP concentration after 72 hours in the continued presence of IL-6. This change in CYP3A4 activity decreased the half-life and AUClast of the small molecule CYP3A4 substrate simvastatin hydroxy acid, measured before and after tocilizumab treatment. We conclude that next-generation in vitro Liver Culture platforms are well-suited for these types of long-term treatment studies and show promise for improved drug safety assessment.
Aziza Amin - One of the best experts on this subject based on the ideXlab platform.
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Cysteine Peptidases, Secreted by Trichomonas gallinae, Are Involved in the Cytopathogenic Effects on a Permanent Chicken Liver Cell Culture
2016Co-Authors: Aziza Amin, Martina Patzl, Evelyn Berger, Michael Hess, Ivana BilicAbstract:Trichomonas gallinae, the aetiological agent of avian trichomonosis, was shown to secrete soluble factors involved in cytopathogenic effect on a permanent chicken Liver (LMH) Cell Culture. The present study focused on the characterization of these molecules. The addition of specific peptidase inhibitors to the Cell-free filtrate partially inhibited the monolayer destruction, which implied the presence of peptidases in the filtrate and their involvement in the cytopathogenic effect. One-dimensional substrate (gelatin) SDS-PAGE confirmed the proteolytic character of the filtrate by demonstrating the proteolytic activity within the molecular weight range from 38 to 110 kDa. In addition, the proteolytic activity was specifically inhibited by addition of TLCK and E-64 cysteine peptidase inhibitors implying their cysteine peptidase nature. Furthermore, variations in the intensity and the number of proteolytic bands were observed between Cell-free filtrates of low and high passages of the same T. gallinae clonal Culture. Two-dimensional substrate gel electrophoresis of concentrated T. gallinae Cell-free filtrate identified at least six proteolytic spots. The mass spectrometric analysis of spots from 2-D gels identified the presence of at least two different Clan CA, family C1, cathepsin L-like cysteine peptidases in the Cell-free filtrate of T. gallinae. In parallel, a PCR approach using degenerated primers based on the conserved amino acid sequence region of cysteine peptidases from Trichomonas vaginalis identified the coding sequences for four different Clan CA, family C1, cathepsin L-like cysteine peptidases. Finally, this is the first report analyzing molecules secreted by T. gallinae an
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cysteine peptidases secreted by trichomonas gallinae are involved in the cytopathogenic effects on a permanent chicken Liver Cell Culture
PLOS ONE, 2012Co-Authors: Aziza Amin, Katharina Nobauer, Martina Patzl, Evelyn Berger, Michael Hess, Ivana BilicAbstract:Trichomonas gallinae, the aetiological agent of avian trichomonosis, was shown to secrete soluble factors involved in cytopathogenic effect on a permanent chicken Liver (LMH) Cell Culture. The present study focused on the characterization of these molecules. The addition of specific peptidase inhibitors to the Cell-free filtrate partially inhibited the monolayer destruction, which implied the presence of peptidases in the filtrate and their involvement in the cytopathogenic effect. One-dimensional substrate (gelatin) SDS-PAGE confirmed the proteolytic character of the filtrate by demonstrating the proteolytic activity within the molecular weight range from 38 to 110 kDa. In addition, the proteolytic activity was specifically inhibited by addition of TLCK and E-64 cysteine peptidase inhibitors implying their cysteine peptidase nature. Furthermore, variations in the intensity and the number of proteolytic bands were observed between Cell-free filtrates of low and high passages of the same T. gallinae clonal Culture. Two-dimensional substrate gel electrophoresis of concentrated T. gallinae Cell-free filtrate identified at least six proteolytic spots. The mass spectrometric analysis of spots from 2-D gels identified the presence of at least two different Clan CA, family C1, cathepsin L-like cysteine peptidases in the Cell-free filtrate of T. gallinae. In parallel, a PCR approach using degenerated primers based on the conserved amino acid sequence region of cysteine peptidases from Trichomonas vaginalis identified the coding sequences for four different Clan CA, family C1, cathepsin L-like cysteine peptidases. Finally, this is the first report analyzing molecules secreted by T. gallinae and demonstrating the ubiquity of peptidases secreted by this protozoon.
Thomas Joseph Long - One of the best experts on this subject based on the ideXlab platform.
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modeling therapeutic antibody small molecule drug drug interactions using a three dimensional perfusable human Liver coCulture platform
PMC, 2016Co-Authors: Thomas Joseph Long, Hisham K Hamadeh, Patrick A Cosgrove, Robert T Dunn, Donna B Stolz, Cynthia A Afshari, Helen J Mcbride, Linda G GriffithAbstract:Traditional in vitro human Liver Cell Culture models lose key hepatic functions such as metabolic activity during short-term Culture. Advanced three-dimensional (3D) Liver coCulture platforms offer the potential for extended hepatocyte functionality and allow for the study of more complex biologic interactions, which can improve and refine human drug safety evaluations. Here, we use a perfusion flow 3D microreactor platform for the coCulture of cryopreserved primary human hepatocytes and Kupffer Cells to study the regulation of cytochrome P450 3A4 isoform (CYP3A4) activity by chronic interleukin 6 (IL-6)-mediated inflammation over 2 weeks. Hepatocyte Cultures remained stable over 2 weeks, with consistent albumin production and basal IL-6 levels. Direct IL-6 stimulation that mimics an inflammatory state induced a dose-dependent suppression of CYP3A4 activity, an increase in C-reactive protein (CRP) secretion, and a decrease in shed soluble interleukin-6 receptor (IL-6R) levels, indicating expected hepatic IL-6 bioactivity. Tocilizumab, an anti-IL-6R monoclonal antibody used to treat rheumatoid arthritis, has been demonstrated clinically to impact small molecule drug pharmacokinetics by modulating cytochrome P450 enzyme activities, an effect not observed in traditional hepatic Cultures. We have now recapitulated the clinical observation in a 3D bioreactor system. Tocilizumab was shown to desuppress CYP3A4 activity while reducing the CRP concentration after 72 hours in the continued presence of IL-6. This change in CYP3A4 activity decreased the half-life and area under the curve up to the last measurable concentration (AUClast) of the small molecule CYP3A4 substrate simvastatin hydroxy acid, measured before and after tocilizumab treatment. We conclude that next-generation in vitro Liver Culture platforms are well suited for these types of long-term treatment studies and show promise for improved drug safety assessment.
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modeling therapeutic antibody small molecule drug drug interactions using a three dimensional perfusable human Liver coCulture platform
Drug Metabolism and Disposition, 2016Co-Authors: Thomas Joseph Long, Hisham K Hamadeh, Patrick A Cosgrove, Robert T Dunn, Donna B Stolz, Cynthia A Afshari, Helen J Mcbride, Linda G GriffithAbstract:Traditional in vitro human Liver Cell Culture models lose key hepatic functions such as metabolic activity during short-term Culture. Advanced 3D Liver co-Culture platforms offer the potential for extended hepatocyte functionality, allowing for the study of more complex biological interactions that can improve and refine human drug safety evaluation. Here, we utilize a perfusion flow 3D microreactor platform for the co-Culture of cryopreserved primary human hepatocytes and Kupffer Cells to study the regulation of CYP3A4 activity by chronic IL-6-mediated inflammation over two weeks. Hepatocyte Cultures remained stable over two weeks, with consistent albumin production and basal IL-6 levels. Direct IL-6 stimulation that mimics an inflammatory state induced a dose-dependent suppression of CYP3A4 activity, an increase in C-reactive protein (CRP) secretion, and a decrease in shed soluble IL-6R levels, indicating expected hepatic IL-6 bioactivity. Tocilizumab, an anti-IL-6R monoclonal antibody used to treat rheumatoid arthritis, has been demonstrated clinically to impact small molecule drug pharmacokinetics by modulating cytochrome P450 enzyme activities, an effect not observed in traditional hepatic Cultures. We have now recapitulated the clinical observation in a 3D bioreactor system. Tocilizumab was shown to de-suppress CYP3A4 activity while reducing CRP concentration after 72 hours in the continued presence of IL-6. This change in CYP3A4 activity decreased the half-life and AUClast of the small molecule CYP3A4 substrate simvastatin hydroxy acid, measured before and after tocilizumab treatment. We conclude that next-generation in vitro Liver Culture platforms are well-suited for these types of long-term treatment studies and show promise for improved drug safety assessment.
Michael Hess - One of the best experts on this subject based on the ideXlab platform.
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Cysteine Peptidases, Secreted by Trichomonas gallinae, Are Involved in the Cytopathogenic Effects on a Permanent Chicken Liver Cell Culture
2016Co-Authors: Aziza Amin, Martina Patzl, Evelyn Berger, Michael Hess, Ivana BilicAbstract:Trichomonas gallinae, the aetiological agent of avian trichomonosis, was shown to secrete soluble factors involved in cytopathogenic effect on a permanent chicken Liver (LMH) Cell Culture. The present study focused on the characterization of these molecules. The addition of specific peptidase inhibitors to the Cell-free filtrate partially inhibited the monolayer destruction, which implied the presence of peptidases in the filtrate and their involvement in the cytopathogenic effect. One-dimensional substrate (gelatin) SDS-PAGE confirmed the proteolytic character of the filtrate by demonstrating the proteolytic activity within the molecular weight range from 38 to 110 kDa. In addition, the proteolytic activity was specifically inhibited by addition of TLCK and E-64 cysteine peptidase inhibitors implying their cysteine peptidase nature. Furthermore, variations in the intensity and the number of proteolytic bands were observed between Cell-free filtrates of low and high passages of the same T. gallinae clonal Culture. Two-dimensional substrate gel electrophoresis of concentrated T. gallinae Cell-free filtrate identified at least six proteolytic spots. The mass spectrometric analysis of spots from 2-D gels identified the presence of at least two different Clan CA, family C1, cathepsin L-like cysteine peptidases in the Cell-free filtrate of T. gallinae. In parallel, a PCR approach using degenerated primers based on the conserved amino acid sequence region of cysteine peptidases from Trichomonas vaginalis identified the coding sequences for four different Clan CA, family C1, cathepsin L-like cysteine peptidases. Finally, this is the first report analyzing molecules secreted by T. gallinae an
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cysteine peptidases secreted by trichomonas gallinae are involved in the cytopathogenic effects on a permanent chicken Liver Cell Culture
PLOS ONE, 2012Co-Authors: Aziza Amin, Katharina Nobauer, Martina Patzl, Evelyn Berger, Michael Hess, Ivana BilicAbstract:Trichomonas gallinae, the aetiological agent of avian trichomonosis, was shown to secrete soluble factors involved in cytopathogenic effect on a permanent chicken Liver (LMH) Cell Culture. The present study focused on the characterization of these molecules. The addition of specific peptidase inhibitors to the Cell-free filtrate partially inhibited the monolayer destruction, which implied the presence of peptidases in the filtrate and their involvement in the cytopathogenic effect. One-dimensional substrate (gelatin) SDS-PAGE confirmed the proteolytic character of the filtrate by demonstrating the proteolytic activity within the molecular weight range from 38 to 110 kDa. In addition, the proteolytic activity was specifically inhibited by addition of TLCK and E-64 cysteine peptidase inhibitors implying their cysteine peptidase nature. Furthermore, variations in the intensity and the number of proteolytic bands were observed between Cell-free filtrates of low and high passages of the same T. gallinae clonal Culture. Two-dimensional substrate gel electrophoresis of concentrated T. gallinae Cell-free filtrate identified at least six proteolytic spots. The mass spectrometric analysis of spots from 2-D gels identified the presence of at least two different Clan CA, family C1, cathepsin L-like cysteine peptidases in the Cell-free filtrate of T. gallinae. In parallel, a PCR approach using degenerated primers based on the conserved amino acid sequence region of cysteine peptidases from Trichomonas vaginalis identified the coding sequences for four different Clan CA, family C1, cathepsin L-like cysteine peptidases. Finally, this is the first report analyzing molecules secreted by T. gallinae and demonstrating the ubiquity of peptidases secreted by this protozoon.
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fowl adenovirus serotype 4 associated with outbreaks of infectious hydropericardium in haryana india
Avian Diseases, 2002Co-Authors: Swati Dahiya, Michael Hess, Ravinder N Srivastava, Baldev R GulatiAbstract:During 1998, hydropericardium syndrome was observed among 3-to-6-wk-old broilers in 45 different flocks of Haryana, India, with mortality ranging between 10% and 30%. Fowl adenovirus (FAV) was isolated from one of the affected flocks by chicken embryo Liver Cell Culture. Serum neutralization test and polymerase chain reaction assay coupled with restriction enzyme analysis confirmed that the isolated virus belonged to FAV serotype 4. The disease was reproduced in 28-day-old broilers by subcutaneous and oral inoculation of isolated FAV4 alone. Typical hydropericardium and basophilic intranuclear inclusions in hepatocytes were observed in experimental birds by day 4 postinoculation.