Introduction La production in vitro, de maniere reproductible et en larges quantite, d’un epithel... more Introduction La production in vitro, de maniere reproductible et en larges quantite, d’un epithelium bronchique a partir de cellules souches pluripotentes est un objectif cle pour le criblage de medicaments a haut debit pour identifier de nouvelles molecules et la production de cellules pour une therapie cellulaire en pneumologie (Pharmacol Ther 2018 :183, 58-77). Methodes Nous avons concu une methode simple et reproductible qui conduit un simple echantillon de sang en hiPSC par reprogrammation, puis differencie en 45 jours en epithelium bronchique en interface air-liquide (iALI), en suivant successivement les etapes cles du developpement que sont la formation de l’endoderme definitif (DE) et de l’endoderme anterieur ventralise (vAFE). Resultats La reprogrammation des cellules sanguines d’un patient sain et de 3 patients atteints de BPCO, ainsi que de fibroblastes derives de la peau obtenus chez un patient PCD, a ete obtenue en utilisant des virus Sendai. La purete moyenne des cellules aux stades DE et vAFE evaluee par l’expression de CXCR4 et NKX2.1, respectivement, etait superieure a 85 %, evitant ainsi la necessite d’un tri cellulaire. Lorsqu’elles sont transferees dans des conditions de culture d’interface air-liquide (ALI), les cellules vAFE se differencient en 4 semaines en epithelium bronchique avec de grandes zones couvertes par les principales sous-populations cellulaires de l’epithelium bronchique : cellules basales (KRT5 + ), ciliees (TubIV + ), a mucus (Muc5AC + ), Club (CCSP + ), ainsi que des cellules neuroendocrines (CHGA + )(epithelium bronchique iALI). La microscopie electronique confirme la presence de cils motiles et leur frequence de battement est similaire a celui observe dans des HBEC. Certains iALI ont ete maintenus pendant plus de 400 jours. Conclusions La reprogrammation et la differenciation fiables des hiPSC derives du sang, quel que soit leur contexte clinique, en epithelium bronchique iALI mature et fonctionnel est maintenant accessible a une utilisation plus large, ce qui permettra de mieux comprendre la pathogenese des maladies pulmonaires et d’accelerer le developpement de nouvelles therapies geniques et la decouverte de medicaments.
Background & Aim Genetic integrity of human pluripotent stem cells (hPSCs) is essential for t... more Background & Aim Genetic integrity of human pluripotent stem cells (hPSCs) is essential for the accuracy of the disease models and for the security of cell therapies that are use those cells. Because genetic abnormalities can accumulate during the generation of hPSC, their long term maintenance or during genome editing, it is mandatory to regularly check the genome of hPSCs. However, the current methods to assess genomic integrity of hPSC are not fully suitable for such regular screening. These approaches can be limited in term of resolution, flexibility, cost and time to process. Our aim is improving genetic screening of hPSC. Methods, Results & Conclusion Based on a large meta-analysis of all hPSC genetic abnormalities reported in more than 100 publications, we were able to exhaustively identify recurrent genetic abnormalities accumulating in hPSCs. We then developed a test (iCS-digital test) based on the droplet digital PCR technology that can detect more than 90% of these hPSC recurrent genetic abnormalities in DNA extracted from culture supernatant samples. This test was successfully used to detect copy number variations that arose during cell culture or gene editing. Hence, the iCS-digital test can be used to routinely screen genomic integrity in hPSCs, contribute to secure genome editing workflow, and reduce time and financial losses induced by the use of an abnormal hPSC lines.
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Recent advances in genome engineering based on the CRISPR/Cas9 technology have revolutionized our... more Recent advances in genome engineering based on the CRISPR/Cas9 technology have revolutionized our ability to manipulate genomic DNA. Its use in human pluripotent stem cells (hPSCs) has allowed a wide range of mutant cell lines to be obtained at an unprecedented rate. The combination of these two groundbreaking technologies has tremendous potential, from disease modeling to stem cell-based therapies. However, the generation, screening and molecular characterization of these cell lines remain a cumbersome and multi-step endeavor. Here, we propose a pipeline of strategies to efficiently generate, sub-clone, and characterize CRISPR/Cas9-edited hPSC lines in the function of the introduced mutation (indels, point mutations, insertion of large constructs, deletions).
Chronic obstructive pulmonary disease (COPD) is a common and preventable airway disease causing s... more Chronic obstructive pulmonary disease (COPD) is a common and preventable airway disease causing significant worldwide mortality and morbidity. Lifetime exposure to tobacco smoking and environmental particles are the two major risk factors. Over recent decades, COPD has become a growing public health problem with an increase in incidence. COPD is defined by airflow limitation due to airway inflammation and small airway remodelling coupled to parenchymal lung destruction. Most patients exhibit neutrophil-predominant airway inflammation combined with an increase in macrophages and CD8 + T-cells. Asthma is a heterogeneous chronic inflammatory airway disease. The most studied subtype is type 2 (T2) high eosinophilic asthma, for which there are an increasing number of biologic agents developed. However, both asthma and COPD are complex and share common pathophysiological mechanisms. They are known as overlapping syndromes as approximately 40% of patients with COPD present an eosinophilic airway inflammation. Several studies suggest a putative role of eosinophilia in lung function decline and COPD exacerbation. Recently, pharmacological agents targeting eosinophilic traits in uncontrolled eosinophilic asthma, especially monoclonal antibodies directed against interleukins (IL-5, IL-4, IL-13) or their receptors, have shown promising results. This review examines data on the rationale for such biological agents and assesses efficacy in T2-endotype COPD patients. Patients with severe COPD and eosinophilic inflammation experience uncontrolled symptoms despite optimal pharmaceutical treatment. The development of new biomarkers is needed for better phenotyping of patients to propose innovative targeted therapy.
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
BACKGROUND: The understanding of the mechanisms regulating human oocyte maturation is still rudim... more BACKGROUND: The understanding of the mechanisms regulating human oocyte maturation is still rudimentary. We have identified transcripts differentially expressed between immature and mature oocytes, and cumulus cells. METHODS: Using oligonucleotides microarrays, genome wide gene expression was studied in pooled immature and mature oocytes or cumulus cells from patients who underwent IVF. RESULTS: In addition to known genes such as DAZL, BMP15 or GDF9, oocytes upregulated 1514 genes. We show that PTTG3 and AURKC are respectively the securin and the Aurora kinase preferentially expressed during oocyte meiosis. Strikingly, oocytes overexpressed previously unreported growth factors such as TNFSF13/APRIL, FGF9, FGF14, and IL4, and transcription factors including OTX2, SOX15 and SOX30. Conversely, cumulus cells, in addition to known genes such as LHCGR or BMPR2, overexpressed cell-tocell signaling genes including TNFSF11/RANKL, numerous complement components, semaphorins (SEMA3A, SEMA6A, SEMA6D) and CD genes such as CD200. We also identified 52 genes progressively increasing during oocyte maturation, comprising CDC25A and SOCS7. CONCLUSION: The identification of genes up and down regulated during oocyte maturation greatly improves our understanding of oocyte biology and will provide new markers that signal viable and competent oocytes. Furthermore, genes found expressed in cumulus cells are potential markers of granulosa cell tumors.
Introduction Asthma is a chronic inflammatory disease characterized by bronchial hyperresponsiven... more Introduction Asthma is a chronic inflammatory disease characterized by bronchial hyperresponsiveness, immune cell infiltration into the airways, airway remodeling and mucus overproduction. Platelets are small anucleated cells known for their role in hemostasis and thrombosis. However, they also exhibit immune and pro-inflammatory functions. Few studies suggest their involvement in the pathophysiology of asthma. The objective of our study was to analyze the transcriptomic profile of platelets from patients with severe asthma compared to non asthmatic subjects. Methods Blood samples were collected from 5 severe asthma patients and 5 non asthmatic controls. Platelets were purified using immunomagnetic separation (Miltenyi Biotec). Total RNA was extracted and analyzed using whole genome U133 Plus 2.0 GeneChip Affymetrix microarrays. Significance analysis of microarray was used to analyze the array data with 2-fold cut-off and false discovery rate (FDR Results The molecular signature of platelets from severe asthmatics was significantly different from the healthy subjects. Specifically, platelets from severe asthma patients were characterized by over-expression of genes related to inflammatory response and infection including CD9, CD36, CD164, SERPINB1, PANX1 and IFITM3. In addition, mRNA transcripts of factors controlling metabolism and transport of molecules such as phospholipase A1 (PLAAT1) and leucine rich repeat (LRRC32) were up-regulated in platelets from severe asthma patients. Conversely, several genes, implicated in cell death and survival (EHMT1, ABCC1, HMOX1, GSTP1, EIF3), were down-regulated. Functional annotation of the differentially expressed genes revealed dysregulation of the Th1 and Th2 activation pathways (CD28, IL12, TSLPR, PI3 K) that play a critical role in the adaptive immunity and therefore impact the pathophysiology of asthma. Conclusion Transcriptome profiling of platelets from severe asthma patients and non-asthmatic controls allowed us to unravel the molecular basis of their special features and to determine candidate genes differentially expressed in these studied groups. This study presents a comprehensive resource to constitute a base for future investigations on the role of platelets in patients with severe asthma.
Posters la littérature, dans le développement craniofacial, principalement dans le développement ... more Posters la littérature, dans le développement craniofacial, principalement dans le développement de la deuxième paire d'arcs branchiaux. Le foetus décrit dans notre cas présente un développement sexuel normal de type féminin (examen histologique des ovaires normal). Les anomalies squelettiques et craniofaciales peuvent, pour certaines d'entre elles, faire évoquer une dysplasie campomélique. Ces données suggèrent un lien entre SOX3 et SOX9 avec la possibilité qu'une surexpression de SOX3 agisse comme une délétion de SOX9. Déclaration de liens d'intérêts Les auteurs déclarent ne pas avoir de liens d'intérêts.
Plus de trente ans aprers la naissance de Louise Brown, les techniques d’assistance medicale a la... more Plus de trente ans aprers la naissance de Louise Brown, les techniques d’assistance medicale a la procreation (AMP) telles que la fecondation in vitro (FIV) ou plus recemment l’injection d’un spermatozoide dans l’ovocyte (ICSI) sont de plus en plus proposees a des couples ayant des difficultes a concevoir spontanement. Des problemes majeurs emergent de ces techniques: le taux eleve de grossesses multiples et un faible taux de succes en termes d’enfant ne par cycle initie. Cela explique en partie le replacement de plusieurs embryons dans la cavite uterine. Actuellement, la diminution du nombre d’embryons a transferer est devenue un imperatif, voire une obligation reglementaire dans certains pays.
Highly reproducible in vitro generation of human bronchial epithelium from pluripotent stem cells... more Highly reproducible in vitro generation of human bronchial epithelium from pluripotent stem cells is an unmet key goal for drug screening to treat lung diseases. The possibility of using induced pluripotent stem cells (hiPSC) to model normal and diseased tissue in vitro from a simple blood sample will reshape drug discovery for chronic lung, monogenic and infectious diseases. We devised a simple and reliable method that drives a blood sample reprogrammed into hiPSC subsequently differentiated within 45 days into air-liquid interface bronchial .
un tournant dans la modélisation des maladies pulmonaires chroniques et pourrait très significati... more un tournant dans la modélisation des maladies pulmonaires chroniques et pourrait très significativement accélérer le développement de nouvelles thérapies. Les organoïdes sont de petits systèmes biologiques structurés en 3 dimensions (3D), résultats de l'auto-organisation des cellules. Ces structures miment in vitro, au moins en partie, le développement et la fonction d'un organe en miniature. Ils reproduisent la complexité des types cellulaires et l'organisation de l'organe. Les premiers organoïdes pulmonaires ont été obtenus à partir de cellules foetales [3] mais c'est grâce aux cellules souches pluripotentes (CSP) [4] et notamment aux cellules souches pluripotentes induites humaines (iPS), que leur utilisation a été popularisée, offrant de nouvelles perspectives. Bien que la définition des organoïdes implique une structure en 3D, la fonction pulmonaire d'interface ouverte sur le milieu extérieur peut être modélisée en 2D de façon légitime, puisqu'une telle organisation est inscrite dans l'architecture de la paroi de la trachée, des bronches, des bronchioles ou des alvéoles. C'est pourquoi cette revue décrira non seulement les organoïdes pulmonaires 3D mais également les épithéliums bronchiques cultivés en 2D, dont les mises au point ont précédé et accompagné celles des structures en 3D. Structure et développement pulmonaire : quand complexité rime avec nécessité L'arbre respiratoire intra-thoracique adulte se divise en deux zones de compositions architecturales et cellulaires bien distinctes qui
Human embryonic stem cells (hESC) are obtained from the inner cell mass from the early embryo at ... more Human embryonic stem cells (hESC) are obtained from the inner cell mass from the early embryo at blastocyste stage. Derived in cell lines for the first time in 1998, they can be maintained in culture in an undifferentiated state indefinitely under certain conditions. Two essential properties characterize hESC: pluripotency and self-renewal. Pluripotency is convey by the expression of specific transcription factors such as OCT4 and NANOG, and is under the control of growth factors such as IGF2 and FGFb. Markers used to characterize these cells include surface antigens, notably SSEA-3 and SSEA-4, and nuclear markers such as OCT4. HESC can differentiate into different cell types in vitro. They represent a unique and essential model for early human development research and for regenerative medicine. By their self-renewal capacity and their potential to differentiate into several cell types, hESC are an unlimited source of cells enabling to replace or restore lost or damaged cells in numerous diseases. Even if it is not conceivable today to use them in clinical practice for ethic and scientific reasons, it seems essential to explore the numerous potentialities of these cells. This knowledge might be relevant to handle adult stem cells in vitro and will be mandatory for a therapeutic use of hESC in the future.
Les cellules souches embryonnaires humaines (CSEh) sont issues de la masse cellulaire interne (MC... more Les cellules souches embryonnaires humaines (CSEh) sont issues de la masse cellulaire interne (MCI) du blastocyste humain au cinquième ou sixième jour du développement embryonnaire précoce. Elles sont pluripotentes-capables de développer en tout type cellulaire-et prolifèrent indéfiniment in vitro. Par ces deux propriétés cardinales, ces cellules sont une source potentiellement très intéressante de cellules pour une médecine régénératrice. Les CSEh sont aussi le modèle de référence d'étude des mécanismes
Introduction La production in vitro, de maniere reproductible et en larges quantite, d’un epithel... more Introduction La production in vitro, de maniere reproductible et en larges quantite, d’un epithelium bronchique a partir de cellules souches pluripotentes est un objectif cle pour le criblage de medicaments a haut debit pour identifier de nouvelles molecules et la production de cellules pour une therapie cellulaire en pneumologie (Pharmacol Ther 2018 :183, 58-77). Methodes Nous avons concu une methode simple et reproductible qui conduit un simple echantillon de sang en hiPSC par reprogrammation, puis differencie en 45 jours en epithelium bronchique en interface air-liquide (iALI), en suivant successivement les etapes cles du developpement que sont la formation de l’endoderme definitif (DE) et de l’endoderme anterieur ventralise (vAFE). Resultats La reprogrammation des cellules sanguines d’un patient sain et de 3 patients atteints de BPCO, ainsi que de fibroblastes derives de la peau obtenus chez un patient PCD, a ete obtenue en utilisant des virus Sendai. La purete moyenne des cellules aux stades DE et vAFE evaluee par l’expression de CXCR4 et NKX2.1, respectivement, etait superieure a 85 %, evitant ainsi la necessite d’un tri cellulaire. Lorsqu’elles sont transferees dans des conditions de culture d’interface air-liquide (ALI), les cellules vAFE se differencient en 4 semaines en epithelium bronchique avec de grandes zones couvertes par les principales sous-populations cellulaires de l’epithelium bronchique : cellules basales (KRT5 + ), ciliees (TubIV + ), a mucus (Muc5AC + ), Club (CCSP + ), ainsi que des cellules neuroendocrines (CHGA + )(epithelium bronchique iALI). La microscopie electronique confirme la presence de cils motiles et leur frequence de battement est similaire a celui observe dans des HBEC. Certains iALI ont ete maintenus pendant plus de 400 jours. Conclusions La reprogrammation et la differenciation fiables des hiPSC derives du sang, quel que soit leur contexte clinique, en epithelium bronchique iALI mature et fonctionnel est maintenant accessible a une utilisation plus large, ce qui permettra de mieux comprendre la pathogenese des maladies pulmonaires et d’accelerer le developpement de nouvelles therapies geniques et la decouverte de medicaments.
Background & Aim Genetic integrity of human pluripotent stem cells (hPSCs) is essential for t... more Background & Aim Genetic integrity of human pluripotent stem cells (hPSCs) is essential for the accuracy of the disease models and for the security of cell therapies that are use those cells. Because genetic abnormalities can accumulate during the generation of hPSC, their long term maintenance or during genome editing, it is mandatory to regularly check the genome of hPSCs. However, the current methods to assess genomic integrity of hPSC are not fully suitable for such regular screening. These approaches can be limited in term of resolution, flexibility, cost and time to process. Our aim is improving genetic screening of hPSC. Methods, Results & Conclusion Based on a large meta-analysis of all hPSC genetic abnormalities reported in more than 100 publications, we were able to exhaustively identify recurrent genetic abnormalities accumulating in hPSCs. We then developed a test (iCS-digital test) based on the droplet digital PCR technology that can detect more than 90% of these hPSC recurrent genetic abnormalities in DNA extracted from culture supernatant samples. This test was successfully used to detect copy number variations that arose during cell culture or gene editing. Hence, the iCS-digital test can be used to routinely screen genomic integrity in hPSCs, contribute to secure genome editing workflow, and reduce time and financial losses induced by the use of an abnormal hPSC lines.
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Recent advances in genome engineering based on the CRISPR/Cas9 technology have revolutionized our... more Recent advances in genome engineering based on the CRISPR/Cas9 technology have revolutionized our ability to manipulate genomic DNA. Its use in human pluripotent stem cells (hPSCs) has allowed a wide range of mutant cell lines to be obtained at an unprecedented rate. The combination of these two groundbreaking technologies has tremendous potential, from disease modeling to stem cell-based therapies. However, the generation, screening and molecular characterization of these cell lines remain a cumbersome and multi-step endeavor. Here, we propose a pipeline of strategies to efficiently generate, sub-clone, and characterize CRISPR/Cas9-edited hPSC lines in the function of the introduced mutation (indels, point mutations, insertion of large constructs, deletions).
Chronic obstructive pulmonary disease (COPD) is a common and preventable airway disease causing s... more Chronic obstructive pulmonary disease (COPD) is a common and preventable airway disease causing significant worldwide mortality and morbidity. Lifetime exposure to tobacco smoking and environmental particles are the two major risk factors. Over recent decades, COPD has become a growing public health problem with an increase in incidence. COPD is defined by airflow limitation due to airway inflammation and small airway remodelling coupled to parenchymal lung destruction. Most patients exhibit neutrophil-predominant airway inflammation combined with an increase in macrophages and CD8 + T-cells. Asthma is a heterogeneous chronic inflammatory airway disease. The most studied subtype is type 2 (T2) high eosinophilic asthma, for which there are an increasing number of biologic agents developed. However, both asthma and COPD are complex and share common pathophysiological mechanisms. They are known as overlapping syndromes as approximately 40% of patients with COPD present an eosinophilic airway inflammation. Several studies suggest a putative role of eosinophilia in lung function decline and COPD exacerbation. Recently, pharmacological agents targeting eosinophilic traits in uncontrolled eosinophilic asthma, especially monoclonal antibodies directed against interleukins (IL-5, IL-4, IL-13) or their receptors, have shown promising results. This review examines data on the rationale for such biological agents and assesses efficacy in T2-endotype COPD patients. Patients with severe COPD and eosinophilic inflammation experience uncontrolled symptoms despite optimal pharmaceutical treatment. The development of new biomarkers is needed for better phenotyping of patients to propose innovative targeted therapy.
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers.
BACKGROUND: The understanding of the mechanisms regulating human oocyte maturation is still rudim... more BACKGROUND: The understanding of the mechanisms regulating human oocyte maturation is still rudimentary. We have identified transcripts differentially expressed between immature and mature oocytes, and cumulus cells. METHODS: Using oligonucleotides microarrays, genome wide gene expression was studied in pooled immature and mature oocytes or cumulus cells from patients who underwent IVF. RESULTS: In addition to known genes such as DAZL, BMP15 or GDF9, oocytes upregulated 1514 genes. We show that PTTG3 and AURKC are respectively the securin and the Aurora kinase preferentially expressed during oocyte meiosis. Strikingly, oocytes overexpressed previously unreported growth factors such as TNFSF13/APRIL, FGF9, FGF14, and IL4, and transcription factors including OTX2, SOX15 and SOX30. Conversely, cumulus cells, in addition to known genes such as LHCGR or BMPR2, overexpressed cell-tocell signaling genes including TNFSF11/RANKL, numerous complement components, semaphorins (SEMA3A, SEMA6A, SEMA6D) and CD genes such as CD200. We also identified 52 genes progressively increasing during oocyte maturation, comprising CDC25A and SOCS7. CONCLUSION: The identification of genes up and down regulated during oocyte maturation greatly improves our understanding of oocyte biology and will provide new markers that signal viable and competent oocytes. Furthermore, genes found expressed in cumulus cells are potential markers of granulosa cell tumors.
Introduction Asthma is a chronic inflammatory disease characterized by bronchial hyperresponsiven... more Introduction Asthma is a chronic inflammatory disease characterized by bronchial hyperresponsiveness, immune cell infiltration into the airways, airway remodeling and mucus overproduction. Platelets are small anucleated cells known for their role in hemostasis and thrombosis. However, they also exhibit immune and pro-inflammatory functions. Few studies suggest their involvement in the pathophysiology of asthma. The objective of our study was to analyze the transcriptomic profile of platelets from patients with severe asthma compared to non asthmatic subjects. Methods Blood samples were collected from 5 severe asthma patients and 5 non asthmatic controls. Platelets were purified using immunomagnetic separation (Miltenyi Biotec). Total RNA was extracted and analyzed using whole genome U133 Plus 2.0 GeneChip Affymetrix microarrays. Significance analysis of microarray was used to analyze the array data with 2-fold cut-off and false discovery rate (FDR Results The molecular signature of platelets from severe asthmatics was significantly different from the healthy subjects. Specifically, platelets from severe asthma patients were characterized by over-expression of genes related to inflammatory response and infection including CD9, CD36, CD164, SERPINB1, PANX1 and IFITM3. In addition, mRNA transcripts of factors controlling metabolism and transport of molecules such as phospholipase A1 (PLAAT1) and leucine rich repeat (LRRC32) were up-regulated in platelets from severe asthma patients. Conversely, several genes, implicated in cell death and survival (EHMT1, ABCC1, HMOX1, GSTP1, EIF3), were down-regulated. Functional annotation of the differentially expressed genes revealed dysregulation of the Th1 and Th2 activation pathways (CD28, IL12, TSLPR, PI3 K) that play a critical role in the adaptive immunity and therefore impact the pathophysiology of asthma. Conclusion Transcriptome profiling of platelets from severe asthma patients and non-asthmatic controls allowed us to unravel the molecular basis of their special features and to determine candidate genes differentially expressed in these studied groups. This study presents a comprehensive resource to constitute a base for future investigations on the role of platelets in patients with severe asthma.
Posters la littérature, dans le développement craniofacial, principalement dans le développement ... more Posters la littérature, dans le développement craniofacial, principalement dans le développement de la deuxième paire d'arcs branchiaux. Le foetus décrit dans notre cas présente un développement sexuel normal de type féminin (examen histologique des ovaires normal). Les anomalies squelettiques et craniofaciales peuvent, pour certaines d'entre elles, faire évoquer une dysplasie campomélique. Ces données suggèrent un lien entre SOX3 et SOX9 avec la possibilité qu'une surexpression de SOX3 agisse comme une délétion de SOX9. Déclaration de liens d'intérêts Les auteurs déclarent ne pas avoir de liens d'intérêts.
Plus de trente ans aprers la naissance de Louise Brown, les techniques d’assistance medicale a la... more Plus de trente ans aprers la naissance de Louise Brown, les techniques d’assistance medicale a la procreation (AMP) telles que la fecondation in vitro (FIV) ou plus recemment l’injection d’un spermatozoide dans l’ovocyte (ICSI) sont de plus en plus proposees a des couples ayant des difficultes a concevoir spontanement. Des problemes majeurs emergent de ces techniques: le taux eleve de grossesses multiples et un faible taux de succes en termes d’enfant ne par cycle initie. Cela explique en partie le replacement de plusieurs embryons dans la cavite uterine. Actuellement, la diminution du nombre d’embryons a transferer est devenue un imperatif, voire une obligation reglementaire dans certains pays.
Highly reproducible in vitro generation of human bronchial epithelium from pluripotent stem cells... more Highly reproducible in vitro generation of human bronchial epithelium from pluripotent stem cells is an unmet key goal for drug screening to treat lung diseases. The possibility of using induced pluripotent stem cells (hiPSC) to model normal and diseased tissue in vitro from a simple blood sample will reshape drug discovery for chronic lung, monogenic and infectious diseases. We devised a simple and reliable method that drives a blood sample reprogrammed into hiPSC subsequently differentiated within 45 days into air-liquid interface bronchial .
un tournant dans la modélisation des maladies pulmonaires chroniques et pourrait très significati... more un tournant dans la modélisation des maladies pulmonaires chroniques et pourrait très significativement accélérer le développement de nouvelles thérapies. Les organoïdes sont de petits systèmes biologiques structurés en 3 dimensions (3D), résultats de l'auto-organisation des cellules. Ces structures miment in vitro, au moins en partie, le développement et la fonction d'un organe en miniature. Ils reproduisent la complexité des types cellulaires et l'organisation de l'organe. Les premiers organoïdes pulmonaires ont été obtenus à partir de cellules foetales [3] mais c'est grâce aux cellules souches pluripotentes (CSP) [4] et notamment aux cellules souches pluripotentes induites humaines (iPS), que leur utilisation a été popularisée, offrant de nouvelles perspectives. Bien que la définition des organoïdes implique une structure en 3D, la fonction pulmonaire d'interface ouverte sur le milieu extérieur peut être modélisée en 2D de façon légitime, puisqu'une telle organisation est inscrite dans l'architecture de la paroi de la trachée, des bronches, des bronchioles ou des alvéoles. C'est pourquoi cette revue décrira non seulement les organoïdes pulmonaires 3D mais également les épithéliums bronchiques cultivés en 2D, dont les mises au point ont précédé et accompagné celles des structures en 3D. Structure et développement pulmonaire : quand complexité rime avec nécessité L'arbre respiratoire intra-thoracique adulte se divise en deux zones de compositions architecturales et cellulaires bien distinctes qui
Human embryonic stem cells (hESC) are obtained from the inner cell mass from the early embryo at ... more Human embryonic stem cells (hESC) are obtained from the inner cell mass from the early embryo at blastocyste stage. Derived in cell lines for the first time in 1998, they can be maintained in culture in an undifferentiated state indefinitely under certain conditions. Two essential properties characterize hESC: pluripotency and self-renewal. Pluripotency is convey by the expression of specific transcription factors such as OCT4 and NANOG, and is under the control of growth factors such as IGF2 and FGFb. Markers used to characterize these cells include surface antigens, notably SSEA-3 and SSEA-4, and nuclear markers such as OCT4. HESC can differentiate into different cell types in vitro. They represent a unique and essential model for early human development research and for regenerative medicine. By their self-renewal capacity and their potential to differentiate into several cell types, hESC are an unlimited source of cells enabling to replace or restore lost or damaged cells in numerous diseases. Even if it is not conceivable today to use them in clinical practice for ethic and scientific reasons, it seems essential to explore the numerous potentialities of these cells. This knowledge might be relevant to handle adult stem cells in vitro and will be mandatory for a therapeutic use of hESC in the future.
Les cellules souches embryonnaires humaines (CSEh) sont issues de la masse cellulaire interne (MC... more Les cellules souches embryonnaires humaines (CSEh) sont issues de la masse cellulaire interne (MCI) du blastocyste humain au cinquième ou sixième jour du développement embryonnaire précoce. Elles sont pluripotentes-capables de développer en tout type cellulaire-et prolifèrent indéfiniment in vitro. Par ces deux propriétés cardinales, ces cellules sont une source potentiellement très intéressante de cellules pour une médecine régénératrice. Les CSEh sont aussi le modèle de référence d'étude des mécanismes
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