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Laurent Mandelbrot - One of the best experts on this subject based on the ideXlab platform.
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Liver Enzyme Elevation in Pregnant Women Receiving Antiretroviral Therapy in the ANRS-French Perinatal Cohort
Journal of Acquired Immune Deficiency Syndromes, 2019Co-Authors: Jeanne Sibiude, Josiane Warszawski, Roland Tubiana, Jerome Le Chenadec, Françoise Meier, Albert Faye, Stéphane Blanche, Laurent MandelbrotAbstract:BACKGROUND: High rates of Liver Enzyme elevation (LEE) in women receiving antiretroviral treatment (ART) during pregnancy have been reported but causes remain unclear. We estimated the prevalence and risk factors of LEE in a national prospective multicenter cohort. METHODS: We studied 5748 pregnant women living with HIV enrolled in the French Perinatal Cohort 2005-2014, treated with ART, with no active hepatitis B or C co-infection. Adjusted hazard ratio (aHR) were estimated using Cox models with ART as time-dependent variable, separately for women on ART at conception and those initiating ART during pregnancy. RESULTS: LEE (grade>1) was observed in 16.7%, grade 3-4 in 2%. Among women with LEE, 6.7% had preeclampsia, 9.8% intrahepatic cholestasis of pregnancy, and 1.4% other identified medical causes. Most LEE (82.2%) were unexplained. In women with unexplained LEE, LEE was the reason for hospitalization in 51 (6%) women, cesarean section in 13 (2%), induction of labour in 3 (0.4%), and change in ART regimen in 49 (6%) women. Unexplained LEE was associated with higher risk of preterm births, p
David T Curiel - One of the best experts on this subject based on the ideXlab platform.
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140. Primary Adenovirus Specific Cytotoxic T Lymphocyte Response Occurs after Viral Clearance and Liver Enzyme Elevation
Molecular Therapy, 2005Co-Authors: Jian Chen, Allan Zajac, Sylvia A. Mcpherson, Pingar Yang, Xin Xu, Qi Wu, David T Curiel, John D MountzAbstract:Top of pageAbstract The relative contribution of the specific cytotoxic T lymphocyte (CTL) response and innate immune response to the clearance of adenovirus (Ad) and its transgene in the context of gene therapy has been a subject of debate. Transient transgene expression was believed due to the elimination of Ad transduced cells by CTLs. To determine the relative contribution of specific CTL killing of Ad-infected hepatocytes, we have utilized a wild-type Ad5 to study viral clearance from the Liver and its associated Liver Enzyme elevation during a primary immune response. Human Ad5 replicates poorly in mice due to species restriction but induces a dominant CTL response to the E1B peptide (AA192 VNIRNCCYI) associated with mouse class I MHC antigen, H2-Db, in C57BL/6 (B6) mice. Thus, Ad5 was used to mimic a low replicative Ad vectors used in humans and an MHC-I tetramer that contains the E1Bp, H2-Db and b2-microglubulin (Db-E1B), was developed and used to detect the Ad-specific CTLs in Ad5-primed mice. After Ad5 infection, the Db-E1B+CD8+T cells were undetectable in the spleen, Liver and lung until day 5, and peaked at day 8. At the peak of the CTL response, 8 days post infection, 10% of CD8+ cells in the spleen. Surprisingly, 45% in the Liver and 55% in the lung of the CD8+ T cells were Db-E1B+, indicating that most CD8+ T cells in target tissue are specifically recruited to these sites. Furthermore, nearly 100% of Db-E1B+CD8+ cells were IFN|[gamma]| and granzyme-B positive with intracellular staining, indicating that the recruited CD8+CTL exhibit potent killing activity. The E1B-specific in vivo CTL response was detected by the transfer of CFSE-labeled, E1B192 peptide-pulsed target cells from H-2b mice into Ad5-primed syngeneic mice. The magnitude of the in vivo CTL response correlated with the number of Db-E1B+ CTLs in the spleen and Liver (r2=0.96, p
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140 primary adenovirus specific cytotoxic t lymphocyte response occurs after viral clearance and Liver Enzyme elevation
Molecular Therapy, 2005Co-Authors: Jian Chen, Allan Zajac, Sylvia A. Mcpherson, Pingar Yang, Xin Xu, Qi Wu, David T Curiel, John D MountzAbstract:Top of pageAbstract The relative contribution of the specific cytotoxic T lymphocyte (CTL) response and innate immune response to the clearance of adenovirus (Ad) and its transgene in the context of gene therapy has been a subject of debate. Transient transgene expression was believed due to the elimination of Ad transduced cells by CTLs. To determine the relative contribution of specific CTL killing of Ad-infected hepatocytes, we have utilized a wild-type Ad5 to study viral clearance from the Liver and its associated Liver Enzyme elevation during a primary immune response. Human Ad5 replicates poorly in mice due to species restriction but induces a dominant CTL response to the E1B peptide (AA192 VNIRNCCYI) associated with mouse class I MHC antigen, H2-Db, in C57BL/6 (B6) mice. Thus, Ad5 was used to mimic a low replicative Ad vectors used in humans and an MHC-I tetramer that contains the E1Bp, H2-Db and b2-microglubulin (Db-E1B), was developed and used to detect the Ad-specific CTLs in Ad5-primed mice. After Ad5 infection, the Db-E1B+CD8+T cells were undetectable in the spleen, Liver and lung until day 5, and peaked at day 8. At the peak of the CTL response, 8 days post infection, 10% of CD8+ cells in the spleen. Surprisingly, 45% in the Liver and 55% in the lung of the CD8+ T cells were Db-E1B+, indicating that most CD8+ T cells in target tissue are specifically recruited to these sites. Furthermore, nearly 100% of Db-E1B+CD8+ cells were IFN|[gamma]| and granzyme-B positive with intracellular staining, indicating that the recruited CD8+CTL exhibit potent killing activity. The E1B-specific in vivo CTL response was detected by the transfer of CFSE-labeled, E1B192 peptide-pulsed target cells from H-2b mice into Ad5-primed syngeneic mice. The magnitude of the in vivo CTL response correlated with the number of Db-E1B+ CTLs in the spleen and Liver (r2=0.96, p<0.01). Interestingly, viral DNA genome and E1B mRNA peaked at day 2 and reduced rapidly by day 6 and then maintained at a stable level without significant change 200 days after infection. Viral clearance correlated with the peak Liver Enzyme response that occurred on day 4, before CTLs became detectable. In contrast, there was no further change in the level of viral DNA genome and E1B mRNA in the Liver or lung as a result of the peak CTL response at day 8. Administration of Ad5 to athymic SCID mice induced no CD8 T cells or in vivo specific CTL response against E1B192 peptide, yet viral clearance and Liver Enzyme response in SCID mice were comparable to those of B6 mice. Taken together, our results suggest that the innate response, but not the CTL response, plays a dominant role in elimination of Ad during a primary response. Stable long-term expression of lower levels of virus and transgene persist for 200 days despite the presence of potent CD8+ CTLs, indicating that they reside in Liver cells that are resistant to CTL elimination. These findings will be useful in developing efficient and safe Ad gene therapy protocols.
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Primary adenovirus-specific cytotoxic T lymphocyte response occurs after viral clearance and Liver Enzyme elevation
Gene Therapy, 2005Co-Authors: Jian Chen, Allan Zajac, Sylvia A. Mcpherson, Pingar Yang, Xin Xu, Kohtaro Fujihashi, Wang X, Qi Wu, David T CurielAbstract:The virus-specific cytotoxic T lymphocyte (CTL) response is a major obstacle to effective deLivery of adenovirus gene therapy. However, its relative role in viral clearance, transgene elimination and hepatotoxicity remains unclear. In this paper, we present an analysis of viral clearance and Liver toxicity in relation to the induction of the virus-specific CD8 T-cell response revealed by an MHC class I tetramer. A surprisingly high number of tetramer+ CD8 T cells were found in the Liver and lung and reached peak values at days 8 and 10, respectively, post-infection. Nearly 100% of these tetramer+ CD8 T cells expressed high levels of granzyme B and IFNγ. Remarkably, Liver viral load and Liver Enzyme elevation peaked early, at days 2 and 4, respectively, post-infection, before the specific CTL response was detectable. After generation of CTLs, there was only minimal Liver damage or further decrease in virus titer. These results indicated that the primary peak response of tetramer+ CTLs does not correlate with the elimination of adenovirus or Liver cytotoxic response.
Jian Chen - One of the best experts on this subject based on the ideXlab platform.
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140. Primary Adenovirus Specific Cytotoxic T Lymphocyte Response Occurs after Viral Clearance and Liver Enzyme Elevation
Molecular Therapy, 2005Co-Authors: Jian Chen, Allan Zajac, Sylvia A. Mcpherson, Pingar Yang, Xin Xu, Qi Wu, David T Curiel, John D MountzAbstract:Top of pageAbstract The relative contribution of the specific cytotoxic T lymphocyte (CTL) response and innate immune response to the clearance of adenovirus (Ad) and its transgene in the context of gene therapy has been a subject of debate. Transient transgene expression was believed due to the elimination of Ad transduced cells by CTLs. To determine the relative contribution of specific CTL killing of Ad-infected hepatocytes, we have utilized a wild-type Ad5 to study viral clearance from the Liver and its associated Liver Enzyme elevation during a primary immune response. Human Ad5 replicates poorly in mice due to species restriction but induces a dominant CTL response to the E1B peptide (AA192 VNIRNCCYI) associated with mouse class I MHC antigen, H2-Db, in C57BL/6 (B6) mice. Thus, Ad5 was used to mimic a low replicative Ad vectors used in humans and an MHC-I tetramer that contains the E1Bp, H2-Db and b2-microglubulin (Db-E1B), was developed and used to detect the Ad-specific CTLs in Ad5-primed mice. After Ad5 infection, the Db-E1B+CD8+T cells were undetectable in the spleen, Liver and lung until day 5, and peaked at day 8. At the peak of the CTL response, 8 days post infection, 10% of CD8+ cells in the spleen. Surprisingly, 45% in the Liver and 55% in the lung of the CD8+ T cells were Db-E1B+, indicating that most CD8+ T cells in target tissue are specifically recruited to these sites. Furthermore, nearly 100% of Db-E1B+CD8+ cells were IFN|[gamma]| and granzyme-B positive with intracellular staining, indicating that the recruited CD8+CTL exhibit potent killing activity. The E1B-specific in vivo CTL response was detected by the transfer of CFSE-labeled, E1B192 peptide-pulsed target cells from H-2b mice into Ad5-primed syngeneic mice. The magnitude of the in vivo CTL response correlated with the number of Db-E1B+ CTLs in the spleen and Liver (r2=0.96, p
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140 primary adenovirus specific cytotoxic t lymphocyte response occurs after viral clearance and Liver Enzyme elevation
Molecular Therapy, 2005Co-Authors: Jian Chen, Allan Zajac, Sylvia A. Mcpherson, Pingar Yang, Xin Xu, Qi Wu, David T Curiel, John D MountzAbstract:Top of pageAbstract The relative contribution of the specific cytotoxic T lymphocyte (CTL) response and innate immune response to the clearance of adenovirus (Ad) and its transgene in the context of gene therapy has been a subject of debate. Transient transgene expression was believed due to the elimination of Ad transduced cells by CTLs. To determine the relative contribution of specific CTL killing of Ad-infected hepatocytes, we have utilized a wild-type Ad5 to study viral clearance from the Liver and its associated Liver Enzyme elevation during a primary immune response. Human Ad5 replicates poorly in mice due to species restriction but induces a dominant CTL response to the E1B peptide (AA192 VNIRNCCYI) associated with mouse class I MHC antigen, H2-Db, in C57BL/6 (B6) mice. Thus, Ad5 was used to mimic a low replicative Ad vectors used in humans and an MHC-I tetramer that contains the E1Bp, H2-Db and b2-microglubulin (Db-E1B), was developed and used to detect the Ad-specific CTLs in Ad5-primed mice. After Ad5 infection, the Db-E1B+CD8+T cells were undetectable in the spleen, Liver and lung until day 5, and peaked at day 8. At the peak of the CTL response, 8 days post infection, 10% of CD8+ cells in the spleen. Surprisingly, 45% in the Liver and 55% in the lung of the CD8+ T cells were Db-E1B+, indicating that most CD8+ T cells in target tissue are specifically recruited to these sites. Furthermore, nearly 100% of Db-E1B+CD8+ cells were IFN|[gamma]| and granzyme-B positive with intracellular staining, indicating that the recruited CD8+CTL exhibit potent killing activity. The E1B-specific in vivo CTL response was detected by the transfer of CFSE-labeled, E1B192 peptide-pulsed target cells from H-2b mice into Ad5-primed syngeneic mice. The magnitude of the in vivo CTL response correlated with the number of Db-E1B+ CTLs in the spleen and Liver (r2=0.96, p<0.01). Interestingly, viral DNA genome and E1B mRNA peaked at day 2 and reduced rapidly by day 6 and then maintained at a stable level without significant change 200 days after infection. Viral clearance correlated with the peak Liver Enzyme response that occurred on day 4, before CTLs became detectable. In contrast, there was no further change in the level of viral DNA genome and E1B mRNA in the Liver or lung as a result of the peak CTL response at day 8. Administration of Ad5 to athymic SCID mice induced no CD8 T cells or in vivo specific CTL response against E1B192 peptide, yet viral clearance and Liver Enzyme response in SCID mice were comparable to those of B6 mice. Taken together, our results suggest that the innate response, but not the CTL response, plays a dominant role in elimination of Ad during a primary response. Stable long-term expression of lower levels of virus and transgene persist for 200 days despite the presence of potent CD8+ CTLs, indicating that they reside in Liver cells that are resistant to CTL elimination. These findings will be useful in developing efficient and safe Ad gene therapy protocols.
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Primary adenovirus-specific cytotoxic T lymphocyte response occurs after viral clearance and Liver Enzyme elevation
Gene Therapy, 2005Co-Authors: Jian Chen, Allan Zajac, Sylvia A. Mcpherson, Pingar Yang, Xin Xu, Kohtaro Fujihashi, Wang X, Qi Wu, David T CurielAbstract:The virus-specific cytotoxic T lymphocyte (CTL) response is a major obstacle to effective deLivery of adenovirus gene therapy. However, its relative role in viral clearance, transgene elimination and hepatotoxicity remains unclear. In this paper, we present an analysis of viral clearance and Liver toxicity in relation to the induction of the virus-specific CD8 T-cell response revealed by an MHC class I tetramer. A surprisingly high number of tetramer+ CD8 T cells were found in the Liver and lung and reached peak values at days 8 and 10, respectively, post-infection. Nearly 100% of these tetramer+ CD8 T cells expressed high levels of granzyme B and IFNγ. Remarkably, Liver viral load and Liver Enzyme elevation peaked early, at days 2 and 4, respectively, post-infection, before the specific CTL response was detectable. After generation of CTLs, there was only minimal Liver damage or further decrease in virus titer. These results indicated that the primary peak response of tetramer+ CTLs does not correlate with the elimination of adenovirus or Liver cytotoxic response.
Jeanne Sibiude - One of the best experts on this subject based on the ideXlab platform.
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Liver Enzyme Elevation in Pregnant Women Receiving Antiretroviral Therapy in the ANRS-French Perinatal Cohort
Journal of Acquired Immune Deficiency Syndromes, 2019Co-Authors: Jeanne Sibiude, Josiane Warszawski, Roland Tubiana, Jerome Le Chenadec, Françoise Meier, Albert Faye, Stéphane Blanche, Laurent MandelbrotAbstract:BACKGROUND: High rates of Liver Enzyme elevation (LEE) in women receiving antiretroviral treatment (ART) during pregnancy have been reported but causes remain unclear. We estimated the prevalence and risk factors of LEE in a national prospective multicenter cohort. METHODS: We studied 5748 pregnant women living with HIV enrolled in the French Perinatal Cohort 2005-2014, treated with ART, with no active hepatitis B or C co-infection. Adjusted hazard ratio (aHR) were estimated using Cox models with ART as time-dependent variable, separately for women on ART at conception and those initiating ART during pregnancy. RESULTS: LEE (grade>1) was observed in 16.7%, grade 3-4 in 2%. Among women with LEE, 6.7% had preeclampsia, 9.8% intrahepatic cholestasis of pregnancy, and 1.4% other identified medical causes. Most LEE (82.2%) were unexplained. In women with unexplained LEE, LEE was the reason for hospitalization in 51 (6%) women, cesarean section in 13 (2%), induction of labour in 3 (0.4%), and change in ART regimen in 49 (6%) women. Unexplained LEE was associated with higher risk of preterm births, p
A. M. Vargas - One of the best experts on this subject based on the ideXlab platform.
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Expression of human Liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase in Escherichia coli. Role of N-2 proline in degradation of the protein.
The Journal of biological chemistry, 1993Co-Authors: Alex J. Lange, A. M. VargasAbstract:Human Liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase is 96% identical to the rat and bovine Liver Enzymes, and all of the critical catalytic and substrate binding residues in both the kinase and bisphosphatase domains are conserved in the three Enzymes. However, in contrast to rat Liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase, which is readily expressed in an Escherichia coli T-7 RNA polymerase-based expression system, the human Liver bifunctional Enzyme could not be expressed in this system. Western blot and slot blot analysis revealed that although both the bifunctional Enzyme protein and its mRNA were rapidly induced by the addition of isopropyl-1-thio-beta-D-galactopyranoside, the protein underwent rapid degradation. Deletion of the N-2 proline residue or its mutation to arginine, the corresponding residue in the rat Liver Enzyme, revealed that this proline residue was responsible for its rapid degradation. The Pro-2-->Arg mutant could be expressed with a high yield (20 mg/liter) in E. coli. The results support the hypothesis that a proline residue at N-2 facilitates bifunctional Enzyme degradation in E. coli. The E. coli expressed mutant form was purified to homogeneity by phosphocellulose chromatography, and its kinetic properties were compared with those of the rat Liver Enzyme. The kinetic properties of the two Enzymes were identical except for the presence of substrate (fructose 6-phosphate) inhibition of the human Liver Enzyme but not of the rat Liver Enzyme. The ability to express and purify large amounts of human Liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase will permit structure/function and x-ray crystal structure studies of the Enzyme and ultimately its targeting for drug therapy.