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Rôle des transporteurs multidrogues (MDR) dans l’accumulation cellulaire d’antibiotiques dans les macrophages J774

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ATP-binding cassette (ABC) transporters are a superfamily proteins that are responsible for expelling various out of the cells. They use ATPhydrolisis as energy source. Some ABC transporters play an important role in cellular detoxification because they transport many xenobiotics out of the cells: they are called MDR (Multi Drug Resistance) transporters. The laboratory is interested in antibiotic efflux. Previous work showed that ciprofloxacin, a fluoroquinolones antibiotic, was substrate for Mrp4 in mouse macrophages, while moxifloxacin, an other fluoroquinolone, was not affected by this transporter.
Because the concentration of antibiotic at its site of action determines its efficacy, the aim of this work was to study the effect of efflux transporters on cellular accumulation of antibiotic in mouse macrophages J774. During this work, I examined in particular two antibiotics: piperacillin, aβ- lactam antibiotic, for which the literature suggests it is substrate for human MRP4, and gemifloxacin, a new fluoroquinolone. Accumulation was determined using cellular models available in the laboratory: namely wild type J774 macrophages and two derived cell-lines that over express or under express Mrp4 transporter, and human THP-1 monocytes.
The results obtained with pipéracilline don’t show any role for Mrp4 in the accumulation of the antibiotic, but they suggest the implication of other transporters: like Bcrp1 and/or P-gp. The results also suggest then evolvement of influx transporters in the cellular accumulation of antibiotics.
With gemifloxacin, we showed a large accumulation in mouse macrophages and human monocytes (2 times higher than for moxifloxacine and about 7 times higher than for ciprofloxacin). Our results also suggest that gemifloxacin is an Mrp4 substrate like ciprofloxacin, because its accumulation is reduced in cells what over express Mrp4. Les transporteurs ABC (ATP Binding Cassette) forment une superfamille de protéines transmembranaires impliquées dans l’efflux de différentes molécules en utilisant l’hydrolyse de l’ATP comme source d’énergie. Certains transporteurs ABC sont particulièrement importants pour la détoxification cellulaire car ils effluent un grand nombre de xénobiotiques : ce sont les transporteurs MDR (Multi Drug Resistance). Le laboratoire s’intéresse en particulier à l’efflux des antibiotiques et a démontré que la ciprofloxacine, un antibiotique de la famille des fluoroquinolones, était substrat du transporteur Mrp4 dans des macrophages de souris alors que la moxifloxacine, une autre fluoroquinolone, n’est pas affectée par ce transporteur.
Sachant que la concentration d’un antibiotique au niveau de son site d’action conditionne son efficacité, ce travail de mémoire a pour but de mettre en évidence l’impact des transporteurs d’efflux sur l’accumulation cellulaire des antibiotiques dans les macrophages de souris J774. Au cours de ce mémoire, je me suis particulièrement intéressée à 2 antibiotiques : la pipéracilline, un antibiotique de la famille des β-lactames pour lequel la littérature suggère qu’elle serait substrat de la pompe MRP4 humaine et la gemifloxacine, une nouvelle fluoroquinolone.
Des expériences d’accumulation d’antibiotiques ont été réalisées sur les modèles cellulaires disponibles au laboratoire : les macrophages J774 sauvages et 2 lignées dérivées qui sur expriment ou sous expriment le transporteur Mrp4, ainsi que sur une lignée de monocytes humains.
Les résultats obtenus concernant la pipéracilline ne permettent pas de mettre en évidence une influence de la pompe Mrp4 de souris sur l’accumulation de cet antibiotique mais suggèrent l’implication d’autres transporteurs : Bcrp1 et/ou P-gp. Les résultats suggèrent également une implication des transporteurs d’influx dans l’accumulation cellulaire de la pipéracilline.
Concernant la gemifloxacine, nous montrons une accumulation importante dans les macrophages de souris et dans les monocytes humains ; 2 fois plus élevée que pour la moxifloxacine et environ 7 fois plus élevée que pour la ciprofloxacine. Nos résultats suggèrent cependant que la gemifloxacine soit substrat de la pompe Prp4 comme la ciproxacine , car son accumulation est réduite dans les cellules qui sur expriment Mrp4


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Advance in the Treatment of Pediatric Leukemia
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Year: 2022 Publisher: Basel MDPI - Multidisciplinary Digital Publishing Institute

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The book gives an overview on the progress that has been made in the treatment of acute lymphoblastic leukemia (ALL), of acute and chronic myeloid leukemia (AML, CML) and of juvenile myelomonocytic leukemia (JMML). Leukemia is the most common malignant disease in children, and 80% of patients are diagnosed with ALL and 15–20% with AML, whereas CML and JMML are rather rare. Although ALL was considered an incurable disease until the early 1960s, with the availability of cytotoxic drugs and the start of clinical multicenter studies, ALL has become an almost curable disease with a survival rate exceeding 90 % in high-income countries. These impressive results have mainly been achieved by a deeper understanding of the genomic landscape of the disease and the introduction of risk stratifications based on genetic features and response to chemotherapy as determined by the presence or absence of minimal residual disease (MRD). Immunotherapies including bispecific T-cell Engagers (BiTEs), Chimeric Antigen Receptor (CAR) T cells, monoclonal antibodies and improvements in the outcome of allogeneic stem cell transplantation (HSCT) have shown impressive results in chemorefractory or relapsed patients, and it is anticipated that the cure rate can be further increased. For countries with less resources, therapies have to be adapted to increase survival as well. This book also updates on the progress made in the treatment of AML. As in ALL, risk classification based on genetic factors and response to chemotherapy is most important for therapy guidance. The book also provides updates and guidance for the treatment of CML and JMML.


Book
Advance in the Treatment of Pediatric Leukemia
Author:
Year: 2022 Publisher: Basel MDPI - Multidisciplinary Digital Publishing Institute

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Abstract

The book gives an overview on the progress that has been made in the treatment of acute lymphoblastic leukemia (ALL), of acute and chronic myeloid leukemia (AML, CML) and of juvenile myelomonocytic leukemia (JMML). Leukemia is the most common malignant disease in children, and 80% of patients are diagnosed with ALL and 15–20% with AML, whereas CML and JMML are rather rare. Although ALL was considered an incurable disease until the early 1960s, with the availability of cytotoxic drugs and the start of clinical multicenter studies, ALL has become an almost curable disease with a survival rate exceeding 90 % in high-income countries. These impressive results have mainly been achieved by a deeper understanding of the genomic landscape of the disease and the introduction of risk stratifications based on genetic features and response to chemotherapy as determined by the presence or absence of minimal residual disease (MRD). Immunotherapies including bispecific T-cell Engagers (BiTEs), Chimeric Antigen Receptor (CAR) T cells, monoclonal antibodies and improvements in the outcome of allogeneic stem cell transplantation (HSCT) have shown impressive results in chemorefractory or relapsed patients, and it is anticipated that the cure rate can be further increased. For countries with less resources, therapies have to be adapted to increase survival as well. This book also updates on the progress made in the treatment of AML. As in ALL, risk classification based on genetic factors and response to chemotherapy is most important for therapy guidance. The book also provides updates and guidance for the treatment of CML and JMML.


Book
Advance in the Treatment of Pediatric Leukemia
Author:
Year: 2022 Publisher: Basel MDPI - Multidisciplinary Digital Publishing Institute

Loading...
Export citation

Choose an application

Bookmark

Abstract

The book gives an overview on the progress that has been made in the treatment of acute lymphoblastic leukemia (ALL), of acute and chronic myeloid leukemia (AML, CML) and of juvenile myelomonocytic leukemia (JMML). Leukemia is the most common malignant disease in children, and 80% of patients are diagnosed with ALL and 15–20% with AML, whereas CML and JMML are rather rare. Although ALL was considered an incurable disease until the early 1960s, with the availability of cytotoxic drugs and the start of clinical multicenter studies, ALL has become an almost curable disease with a survival rate exceeding 90 % in high-income countries. These impressive results have mainly been achieved by a deeper understanding of the genomic landscape of the disease and the introduction of risk stratifications based on genetic features and response to chemotherapy as determined by the presence or absence of minimal residual disease (MRD). Immunotherapies including bispecific T-cell Engagers (BiTEs), Chimeric Antigen Receptor (CAR) T cells, monoclonal antibodies and improvements in the outcome of allogeneic stem cell transplantation (HSCT) have shown impressive results in chemorefractory or relapsed patients, and it is anticipated that the cure rate can be further increased. For countries with less resources, therapies have to be adapted to increase survival as well. This book also updates on the progress made in the treatment of AML. As in ALL, risk classification based on genetic factors and response to chemotherapy is most important for therapy guidance. The book also provides updates and guidance for the treatment of CML and JMML.

Keywords

Research & information: general --- Chemistry --- acute lymphoblastic leukemia --- pediatric --- advances --- diagnosis --- treatment --- immunotherapy --- bispecific T-cell engager (BiTE) --- BCP-ALL --- leukemia --- TRAIL --- antibody --- Fc-engineering --- xenograft --- CD19 --- juvenile myelomonocytic leukemia --- RAS signaling --- hematopoietic stem cell transplantation --- 5-azacitidine --- myelodysplastic/myeloproliferative disorders --- targeted therapy --- ADC --- antibody-drug conjugate --- pediatric leukemia --- ALL --- AML --- allogeneic stem cell transplantation --- acute myeloid leukemia --- minimal residual disease --- conditioning regimen --- alternative donors --- B-ALL --- DUX4 --- IKZF1 --- PAX5 --- Ph-like --- ZNF384 --- NUTM1 --- T-ALL --- NOTCH1 --- BCL11B --- transcriptome --- genome --- chronic myeloid leukemia --- CML --- tyrosine kinase inhibitor --- immunizations --- COVID-19 --- childhood acute lymphoblastic leukemia --- low-risk ALL --- risk-stratified treatment --- treatment related toxicity --- L-asparaginase --- acute pancreatitis --- polymorphism --- SNV --- ABCC4 --- CFTR --- other extramedullary relapse --- lymphoblastic leukemia --- children --- prognosis --- evolution of CAR T cells --- FDA-approved CAR products --- TcR versus CAR --- limitations and complications of CAR T cell therapy --- future directions of CAR T cell therapy --- acute lymphoblastic leukemia --- pediatric --- advances --- diagnosis --- treatment --- immunotherapy --- bispecific T-cell engager (BiTE) --- BCP-ALL --- leukemia --- TRAIL --- antibody --- Fc-engineering --- xenograft --- CD19 --- juvenile myelomonocytic leukemia --- RAS signaling --- hematopoietic stem cell transplantation --- 5-azacitidine --- myelodysplastic/myeloproliferative disorders --- targeted therapy --- ADC --- antibody-drug conjugate --- pediatric leukemia --- ALL --- AML --- allogeneic stem cell transplantation --- acute myeloid leukemia --- minimal residual disease --- conditioning regimen --- alternative donors --- B-ALL --- DUX4 --- IKZF1 --- PAX5 --- Ph-like --- ZNF384 --- NUTM1 --- T-ALL --- NOTCH1 --- BCL11B --- transcriptome --- genome --- chronic myeloid leukemia --- CML --- tyrosine kinase inhibitor --- immunizations --- COVID-19 --- childhood acute lymphoblastic leukemia --- low-risk ALL --- risk-stratified treatment --- treatment related toxicity --- L-asparaginase --- acute pancreatitis --- polymorphism --- SNV --- ABCC4 --- CFTR --- other extramedullary relapse --- lymphoblastic leukemia --- children --- prognosis --- evolution of CAR T cells --- FDA-approved CAR products --- TcR versus CAR --- limitations and complications of CAR T cell therapy --- future directions of CAR T cell therapy

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