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Pluripotent stem cell-derived hepatocytes differentiated in monolayer culture are known to have more fetal than adult hepatocyte characteristics. If numerous studies tend to show that this immature phenotype might not necessarily be an obstacle to their use in transplantation, other applications such as drug screening, toxicological studies, or bioartificial livers are reliant on hepatocyte functionality and require full differentiation of hepatocytes. New technologies have been used to improve the differentiation process in recent years, usually evaluated by measuring the albumin production and CYP450 activity. Here we used the complex production and most importantly the activity of the coagulation factor IX (FIX) produced by mature hepatocytes to assess the differentiation of hemophilia B (HB) patient's induced pluripotent stem cells (iPSCs) in both monolayer culture and organoids.Indeed, HB is an X-linked monogenic disease due to an impaired activity of FIX synthesized by hepatocytes in the liver. We have developed an in vitro model of HB hepatocytes using iPSCs generated from fibroblasts of a severe HB patient. We used CRISPR/Cas9 technology to target the genomic insertion of a coagulation factor 9 minigene bearing the Padua mutation to enhance FIX activity. Noncorrected and corrected iPSCs were differentiated into hepatocytes under both two-dimensional and three-dimensional differentiation protocols and deciphered the production of active FIX in vitro. Finally, we assessed the therapeutic efficacy of this approach in vivo using a mouse model of HB.Functional FIX, whose post-translational modifications only occur in fully mature hepatocytes, was only produced in corrected iPSCs differentiated in organoids. Immunohistochemistry analyses of mouse livers indicated a good cell engraftment, and the FIX activity detected in the plasma of transplanted animals confirmed rescue of the bleeding phenotype.

The conversation is about different historical, cultural and religious views and norms that may have an impact on prenatal testing practices. The Israeli anthropologist Tsipy Ivry, who is interested in Jewish religious communities, and the German theologian and philosopher Hille Haker, who studies Christian religious narratives and ethics, talk about religious ideas and narratives, Rabbinic reasonings and Christian church doctrines, women's health care and feelings, religious authorities and their impact on diagnostic practices, and different understandings of the need for genetic knowledge about our offspring and the moral status of the foetus.

Discussing the language of science and technology in the Romance languages is highly complex and challenging for several reasons. On the one hand, there are different fields to be included, namely computer sciences, engineering, mathematics, as well as physics and astronomy. On the other hand, English has become (or even has always been in the case of computer sciences) the lingua franca in all these fields, so there seems to be rather little to analyze from a synchronic perspective as far as the Romance languages are concerned, and accordingly there is rather little up-to-date linguistic research on it. In the beginning, that is, during the late 1980s, the focus was on specific phenomena, while modern research often deals with didactic aspects and language teaching. When it comes to the state of research in the different Romance languages, it turns out that it is mainly Canadians who are noted for playing a major role in the analysis of French technolectes. Numerous studies, some of which were conducted by German Romanists, center on the lexis and terminology of specific fields in French. As for Portuguese, most works have been published in Brazil, and lately the focal point seems to have primarily been placed on computer science and mathematics. Studies regarding Italian typically reveal a major interest in the general structure of terminology and its relation to everyday language use. Moreover, special emphasis is often placed on historical matters, especially the role of Galileo. Finally, the influence of specific text types as well as didactic aspects of special languages at different levels of education is also a subject of interest. With regard to Spanish, it should first be pointed out that, due to diatopic variation, it is hardly possible to talk about one single concept of the language of science and technology. Only a few comprehensive works on this area of research exist, yet many individual studies have been published in the last few decades, primarily on information science, especially the influence of English on Spanish, as well as on terminology in different fields. In Catalan, specialized languages emerged rather early, and their development has been systematically encouraged since the 20th century; the center of interest in current research is mainly on information science.

BACKGROUND: High intraoperative PEEP with recruitment manoeuvres may improve perioperative outcomes. We re-examined this question by conducting a patient-level meta-analysis of three clinical trials in adult patients at increased risk for postoperative pulmonary complications who underwent non-cardiothoracic and non-neurological surgery. METHODS: The three trials enrolled patients at 128 hospitals in 24 countries from February 2011 to February 2018. All patients received volume-controlled ventilation with low tidal volume. Analyses were performed using one-stage, two-level, mixed modelling (site as a random effect; trial as a fixed effect). The primary outcome was a composite of postoperative pulmonary complications within the first week, analysed using mixed-effect logistic regression. Pre-specified subgroup analyses of nine patient characteristics and seven procedure and care-delivery characteristics were also performed. RESULTS: Complete datasets were available for 1913 participants ventilated with high PEEP and recruitment manoeuvres, compared with 1924 participants who received low PEEP. The primary outcome occurred in 562/1913 (29.4%) participants randomised to high PEEP, compared with 620/1924 (32.2%) participants randomised to low PEEP (unadjusted odds ratio [OR]=0.87; 95% confidence interval [95% CI], 0.75-1.01; P=0.06). Higher PEEP resulted in 87/1913 (4.5%) participants requiring interventions for desaturation, compared with 216/1924 (11.2%) participants randomised to low PEEP (OR=0.34; 95% CI, 0.26-0.45). Intraoperative hypotension was associated more frequently (784/1913 [41.0%]) with high PEEP, compared with low PEEP (579/1924 [30.1%]; OR=1.87; 95% CI, 1.60-2.17). CONCLUSIONS: High PEEP combined with recruitment manoeuvres during low tidal volume ventilation in patients undergoing major surgery did not reduce postoperative pulmonary complications. CLINICAL TRIAL REGISTRATION: NCT03937375 (Clinicaltrials.gov).

In multicellular organisms, the specification, coordination, and compartmentalization of cell types enable the formation of complex body plans. However, some eukaryotic protists such as slime molds generate diverse and complex structures while remaining in a multinucleate syncytial state. It is unknown if different regions of these giant syncytial cells have distinct transcriptional responses to environmental encounters and if nuclei within the cell diversify into heterogeneous states. Here, we performed spatial transcriptome analysis of the slime mold Physarum polycephalum in the plasmodium state under different environmental conditions and used single-nucleus RNA-sequencing to dissect gene expression heterogeneity among nuclei. Our data identifies transcriptome regionality in the organism that associates with proliferation, syncytial substructures, and localized environmental conditions. Further, we find that nuclei are heterogenous in their transcriptional profile and may process local signals within the plasmodium to coordinate cell growth, metabolism, and reproduction. To understand how nuclei variation within the syncytium compares to heterogeneity in single-nucleus cells, we analyzed states in single Physarum amoebal cells. We observed amoebal cell states at different stages of mitosis and meiosis, and identified cytokinetic features that are specific to nuclei divisions within the syncytium. Notably, we do not find evidence for predefined transcriptomic states in the amoebae that are observed in the syncytium. Our data shows that a single-celled slime mold can control its gene expression in a region-specific manner while lacking cellular compartmentalization and suggests that nuclei are mobile processors facilitating local specialized functions. More broadly, slime molds offer the extraordinary opportunity to explore how organisms can evolve regulatory mechanisms to divide labor, specialize, balance competition with cooperation, and perform other foundational principles that govern the logic of life., eLife, 11, ISSN:2050-084X

This contribution is providing a personal perception of pit lakes in the lignite mining districts of the former German Democratic Republic (GDR). In addition, it provides selected facts and a condensed summary on what has been done and achieved since the 1990s to shape the impressive pit lake landscapes that nowadays comprise more than 50 large unique pit lakes.

Bicircular twisted Laguerre-Gaussian beams possess a definite torus knot angular momentum (TKAM) as a new form of angular momentum. TKAM is conserved in nonlinear atomic processes such as high harmonic generation and can be classified by a time delay parameter $\tau$ and a coordination parameter $\gamma$. These parameters are defined by the respective projected orbital angular momentum and the energy of the two superimposed Laguerre-Gaussian beams. We derive a consistent geometric method to determine $\tau$ and $\gamma$ from the driving beam as well as from the high harmonic radiation. This method relates both invariance parameters ($\tau$ and $\gamma$) to the emitted high harmonic radiation. Therefore, $\tau$ and $\gamma$ can be read off of two different torus knots. These knots can be constructed from the spatio-temporal evolution of the electric field of the respective high harmonic radiation or the driving beam. We demonstrate the classification of the invariance parameters for a planar atomic gas target irradiated by bicircular Laguerre-Gaussian beams explicitly. Furthermore, we demonstrate that the respective torus knots determined by $\tau$ and $\gamma$ can be mapped onto each other within minor modifications. This geometric method yields a different way to interpret the invariance parameters $\tau$ and $\gamma$ as well as their underlying relation compared to a purely formal derivation. The investigations presented in this work are in good agreement with previous findings and provide insight into the dynamical symmetry of TKAM in the context of high harmonic generation induced by bicircular twisted Laguerre-Gaussian beams.

The relationship between the Commissioner for Human Rights and the European Court of Human Rights has varied considerably over time, from a clear separation of functions to increasing interactions. Resolution (99) 50 on the Council of Europe Commissioner for Human Rights, adopted on 7 May 1999, reflects a clear willingness to separate the two institutions. This separation, however, did not mean isolation from each other in practice and did not prevent cross-references between the Commissioner and the Court from increasing over the years. In the course of his/ her country or thematic work, the Commissioner relies on international and European conventions, and in the first place the Convention and the case law of the Court, when making recommendations to member states. Conversely, the Court has from the outset made references to the work of the Commissioner in its judgments. While the different roles of the two institutions might explain the sometimes diverging approaches, cross-references between the Commissioner and the Court have undoubtedly enriched each other’s work. With the entry into force of Protocol n º 14 to the Convention in 2010, the Commissioner’s functions have been formally extended, providing formal recognition to the institution of the Commissioner, which is expressly introduced in the text of the Convention and into the control mechanism established by the Convention. The Commissioner may now on his/ her own initiative exercise the right to intervene as a third-party before the Court, by submitting written comments and taking part in hearings. This possibility represents an additional tool at the Commissioner’s disposal to help promote and protect human rights. The Commissioner’s role in the process of execution of the Court’s judgments has also increased over the years. With the amendment introduced in 2017 to the Rules of the Committee of Ministers for the supervision of the execution of judgments (Rule 9), which allows the Commissioner to submit written comments on the execution of judgments directly to the Committee of Ministers, the contribution by the Commissioner to the execution of judgments is expected to have a greater impact., La relation entre le/ la Commissaire aux droits de l’homme et la Cour européenne des droits de l’homme a considérablement évolué au fil du temps, allant d’une séparation claire des fonctions à des interactions croissantes. La Résolution (99) 50 sur le Commissaire aux droits de l’homme du Conseil de l’Europe, adoptée le 7 mai 1999, reflète une volonté claire de séparer les deux institutions. Cette séparation ne s’est cependant pas traduite par un isolement l’un de l’autre dans la pratique et n’a pas empêché les références croisées entre le/ la Commissaire et la Cour de se multiplier au cours des années. Dans le cadre de son travail par pays ou thématique, le/ la Commissaire s’appuie sur les conventions internationales et européennes, et en premier lieu sur la Convention et la jurisprudence de la Cour, lorsqu’il/ elle formule des recommandations aux États membres. Réciproquement, la Cour a d’emblée fait référence aux travaux du/ de la Commissaire dans ses arrêts. Si les rôles différents des deux institutions peuvent expliquer des approches parfois divergentes, les références croisées entre le/ la Commissaire et la Cour ont sans aucun doute enrichi leur travail respectif. Avec l’entrée en vigueur du Protocole n º 14 à la Convention en 2010, les fonctions du/ de la Commissaire ont été formellement étendues, donnant une reconnaissance formelle à l’institution, qui est expressément introduite dans le texte de la Convention et dans le mécanisme de contrôle établi par la Convention. Le/ la Commissaire peut à présent, de sa propre initiative, intervenir en tant que tierce partie devant la Cour en soumettant des observations écrites et en prenant part aux audiences. Cette possibilité représente un outil supplémentaire à la disposition du/ de la Commissaire afin de promouvoir et protéger les droits de l’homme. Le rôle du/ de la Commissaire dans le processus d’exécution des arrêts de la Cour s’est également accru au fil des ans. Avec l’amendement introduit en 2017 aux Règles du Comité des Ministres pour la surveillance de l’exécution des arrêts (Règle 9), qui permet au/ à la Commissaire de soumettre des commentaires écrits sur l’exécution des arrêts directement au Comité des Ministres, la contribution du/ de la Commissaire à l’exécution des arrêts devrait avoir un impact plus important., La relación entre el/ la Comisario/ Comisaria de derechos humanos y la Corte europea de derechos humanos ha cambiado bastante a lo largo del tiempo, yendo de una separación clara de las funciones a interacciones cada vez mayores. La Resolución (99) 50 sobre el Comisario de derechos humanos del Consejo de Europa, adoptada el 7 de mayo 1999 demuestra una voluntad clara de separar las dos instituciones. Esa separación no tuvo como resultado el aislamiento del uno o del otro en la práctica y no impidió que las referencias cruzadas entre el/ la Comisario/ Comisaria y la Corte se multiplicaran a través de los años. En el marco de su trabajo por país o temáticas, el/ la Comisario/ Comisaria se apoya sobre las convenciones internacionales, y en primer lugar sobre la Convención y la jurisprudencia de la Corte, para formula recomendaciones a los Estados miembros. Mutualmente, la Corte hizo referencia, desde su comienzo, a los trabajos del/ de la Comisario/ Comisaria en sus sentencias. Si los papeles diferentes de las dos instituciones pueden explicar enfoques diferentes, las referencias cruzadas entre el/ la Comisario/ Comisaria enriquecieron sin duda sus trabajos respectivos. Con la entrada en vigor del Protocolo n º 14 de la Convención en 2010, las funciones del/ de la Comisario/ Comisaria fueron formalmente extendidas, dándole un reconocimiento formal a la institución, que fue expresamente introducida en el texto de la Convención y en el mecanismo de control establecido por la Convención. El/ la Comisario/ Comisaria puede ahora, de su propra iniciativa, intervenir como tercero frente a la Corte, enviando observaciones escritas y tomando lugar en las audiencias. Esta posibilidad representa una herramienta suplementaria a la disposición del/ de la Comisario/ Comisaria para promover y proteger los derechos humanos. El papel del/ de la Comisario/ Comisaria en el proceso de ejecución de las sentencias de la Corte también creció a través de los años. Con la enmienda de las Reglas del Comité de Ministro para la vigilancia de la ejecución de las sentencias (Regla 9), introducida en 2017, que permite al/ a la Comisario/ Comisaria de someter comentarios escritos sobre la ejecución de las sentencias directamente al Comité de Ministros, la contribución del/ de la Comisario/ Comisaria a la ejecución de las sentencias debería tener un impacto más importante., Mijatović Dunja, Weber Anne. The Council of Europe Commissioner for Human Rights and the European Court of Human Rights: An Ever-closer Relationship. In: Revue Québécoise de droit international, Hors-série décembre 2020 – 70 ans de la Convention européenne des droits de l’homme : L’Europe et les droits de la personne. pp. 79-97.

In this chapter, we will first introduce the causes of familial hypercholesterolemia disease, available treatments, and cell and animal models. As they keep the mutations inside their genome after reprogramming, patient's specific human-induced pluripotent stem cells (hiPSCs) seem to be the most relevant cells to model familial hypercholesterolemia. In a second part, we will thus describe the different signaling pathways used to differentiate hiPSCs into hepatocyte-like cells before focusing on familial hypercholesterolemia cell models based on these cells. We will then finally discuss genetic correction and genome editing to rescue a normal phenotype in these particular cell models.

Silicone embolism syndrome (SES) is a well known complication after injection of silicone gel as well as liquid silicone. Rarely, men use physiologic salt solution or liquid silicone injected into the subcutaneous tissue of the scrotum, the penis, the upper genital or the inguinal region. Those men, who call themselves “siliconers”, want to get a larger penis and scrotum, also visible when wearing clothes. Injections of liquid silicone in the mentioned regions can lead to liquid silicone embolism in the lungs and also the liver, sometimes eventually leading to death via right heart failure as in the present case. Autopsy revealed “frog spawn”-like vacuoles in the subcutaneous tissue of the genital region and liquid silicone embolism in lungs and liver. Additionally, toxicological analyses revealed different liquid silicones. Smaller oligomers were transported into lung and liver, larger ones showed local enrichment at the injection site. The seized Polydimethylsiloxane (PDMS) could not be detected in abdominal fat, blood or urine, potentially due to low perfusion of fat tissue, the aqueous character of blood and urine or the time span between last injection and death.

Background Familial hypercholesterolemia type IIA (FH) is due to mutations in the low-density lipoprotein receptor (LDLR) resulting in elevated levels of low-density lipoprotein cholesterol (LDL-c) in plasma and in premature cardiovascular diseases. As hepatocytes are the only cells capable of metabolizing cholesterol, they are therefore the target cells for cell/gene therapy approaches in the treatment of lipid metabolism disorders. Furthermore, the LDLR has been reported to be involved in hepatitis C virus (HCV) entry into hepatocytes; however, its role in the virus infection cycle is still disputed. Methods We generated induced pluripotent stem cells (iPSCs) from a homozygous LDLR-null FH-patient (FH-iPSCs). We constructed a correction cassette bearing LDLR cDNA under the control of human hepatic apolipoprotein A2 promoter that targets the adeno-associated virus integration site AAVS1. We differentiated both FH-iPSCs and corrected FH-iPSCs (corr-FH-iPSCs) into hepatocytes to study statin-mediated regulation of genes involved in cholesterol metabolism. Upon HCV particle inoculation, viral replication and production were quantified in these cells. Results We showed that FH-iPSCs displayed the disease phenotype. Using homologous recombination mediated by the CRISPR/Cas9 system, FH-iPSCs were genetically corrected by the targeted integration of a correction cassette at the AAVS1 locus. Both FH-iPSCs and corr-FH-iPSCs were then differentiated into functional polarized hepatocytes using a stepwise differentiation approach (FH-iHeps and corr-FH-iHeps). The correct insertion and expression of the correction cassette resulted in restoration of LDLR expression and function (LDL-c uptake) in corr-FH-iHeps. We next demonstrated that pravastatin treatment increased the expression of genes involved in cholesterol metabolism in both cell models. Moreover, LDLR expression and function were also enhanced in corr-FH-iHeps after pravastatin treatment. Finally, we demonstrated that both FH-iHeps and corr-FH-iHeps were as permissive to viral infection as primary human hepatocytes but that virus production in FH-iHeps was significantly decreased compared to corr-FH-iHeps, suggesting a role of the LDLR in HCV morphogenesis. Conclusions Our work provides the first LDLR-null FH cell model and its corrected counterpart to study the regulation of cholesterol metabolism and host determinants of HCV life cycle, and a platform to screen drugs for treating dyslipidemia and HCV infection. Electronic supplementary material The online version of this article (10.1186/s13287-019-1342-6) contains supplementary material, which is available to authorized users.

A four-month-old male intact domestic shorthair kitten was presented for deformity of the right thoracic limb. Severe carpal varus was noted, and palpation of the ventral thorax revealed the sternum to be divided caudally. The heartbeat was palpable beneath the skin in the expanse created by the sternal division. Incomplete caudal sternal cleft with diaphragmatic hernia was diagnosed. At surgery, herniation of the gall bladder and portions of the liver into the thoracic cavity were noted. The medial aspects of the sternal bars were abraded with rongeurs, and interrupted sutures were placed around the sternebrae to close the thorax following placement of a thoracostomy tube. The diaphragm and abdomen were also closed primarily. The kitten died postoperatively and was found to have acute pulmonary and cardiac lesions. Primary surgical closure is possible, and patients should be monitored carefully in the postoperative period.

Gap junctions are intercellular channels made of connexins (Cxs) that allow direct communication between adjacent cells. Modulation of Cxs has been associated with abnormal development and function of the mammary gland and breast cancer. However, the mechanisms underlying their expression during normal mammary gland are not yet known. Cxs interact with components of tight and adherens junctions. Thus, we hypothesized that the expression levels of Cxs vary during mammary gland development and are regulated through stage-dependent interactions with members of the tight and adherens junctions. Our specific objectives were to: 1) determine the expression of Cxs and tight and adherens junction proteins throughout development and 2) characterize Cxs interactions with components of tight and adherens junctions. Murine mammary glands were sampled at various developmental stages (pre-pubescent to post-weaning). RT-qPCR and western-blot analyses demonstrated differential expression patterns for all gap (Cx43, Cx32, Cx26, Cx30), tight (Claudin-1, -3, -4, -7) and adherens (β-catenin, E- and P-cadherins) junctions throughout development. Interestingly, co-immunoprecipitation demonstrated interactions between these different types of junctions. Cx30 interacted with Cx26 just at the late pregnancy stage. While Cx43 showed a persistent interaction with β-catenin from virginity to post-weaning, its interactions with E-cadherin and Claudin-7 were transient. Cx32 interacted with Cx26, E-cadherin and β-catenin during lactation. Immunofluorescence results confirmed the existence of a junctional nexus that remodeled during mammary gland development. Together, our results confirm that the expression levels of Cxs vary concomitantly and that Cxs form junctional nexuses with tight and adherens junctions, suggesting the existence of common regulatory pathways.

Afatinib is an oral irreversible ErbB-Family Blocker indicated for treatment of patients with EGFR mutation positive advanced non-small cell lung cancer. This trial assessed whether renal impairment influences the pharmacokinetics and safety of afatinib. This was an open-label, single-dose study. Pharmacokinetic parameters after afatinib 40 mg were investigated in subjects with moderate (n = 8) or severe (n = 8) renal impairment (estimated glomerular filtration rate 30–59 mL/min/1.73 m2 and 15–29 mL/min/1.73 m2, respectively) and healthy matched controls (n = 14). Plasma and urine samples were collected before and up to 14 days after dosing for pharmacokinetic and plasma protein-binding assessment. Primary endpoints were area under the plasma concentration–time curve from time zero to the last quantifiable concentration (AUClast) and maximum plasma concentration (C max) between subjects with renal impairment and healthy matched controls. Pharmacokinetic profiles and plasma protein binding were similar in all groups. The extent of exposure, as indicated by AUClast and C max, was generally similar between the matched treatment groups, with the exception of the geometric mean ratio of AUClast for subjects with severe renal impairment, which showed a trend towards a higher value compared with matched healthy subjects (150.0 % [90 % CI 105.3–213.7]) Inter-individual variability was moderate (geometric mean coefficient of variation 28–39 % for moderate impairment, 34–42 % for severe impairment). Afatinib was well tolerated and urinary excretion was minimal. Moderate-to-severe renal impairment had a minor influence on the pharmacokinetics of afatinib that was within the observed inter-individual variability, suggesting that afatinib treatment can be considered in this patient population. Registered at ClinicalTrials.gov as NCT02096718.

This article examines the Mexican grassroots base of the Partido Liberal Mexicano (PLM) and PLM members who belonged to the Industrial Workers of the World (IWW). It suggests that a grassroots perspective, one that is also multilingual and transnational, reframes both the PLM and the IWW. Eschewing an institutional approach, this perspective suggests that the organizational underbelly for much of this work rested with Mexican social networks that formed the labor crews, strikes, foci, and union locals. PLM supporters prepared for a Mexican revolution. Some of them did so while organizing IWW locals. Within the context of the intense migration of the period, labor and revolutionary foci moved across binational space, facilitating the spread of ideas, organizing, strikes, and revolutionary forays that were, in effect, binational “circularities of struggle.” These Wobblies of the PLM challenged industrial capitalism, questioned U.S. imperialism and racism, and helped launch the first social revolution in Mexico. This perspective reframes the IWW as one part of a spectrum of organizations attempting to counteract dispossession; yet it simultaneously reveals the organization as more expansive, diverse, multilingual, and transnational than previously presented. By decentering the United States and Europe, this Mexican perspective contributes to a re-envisioned transnational internationalist Left that includes the Americas and opens interpretative frameworks that cross gender, racial, ethnic, and national categories.

Le foie est associe a de nombreuses pathologies parmi lesquelles les maladies metaboliques et cholestatiques, les cirrhoses, les hepatites chroniques et aigues. Toutefois, la connaissance des mecanismes impliques dans la physiopathologie de ces maladies reste limitee du fait de la restriction des biopsies hepatiques et de l’absence de modeles cellulaires derives des patients qui en resulte. Le foie est aussi l’organe principal pour l’elimination des xenobiotiques et de ce fait les hepatocytes jouent un role clef en toxicologie et en pharmacocinetique. Les cellules souches pluripotentes induites generees a partir de patients atteints de maladies metaboliques monogeniques, pour lesquelles le gene correspondant est connu, representent un modele in vitro pertinent, d’une part pour l’etude des mecanismes impliques dans la maladie ciblee, et d’autre part pour le criblage de medicaments pour sa correction. A cet effet, des protocoles efficaces pour generer des cellules hepatiques, les hepatocytes et les cholangiocytes, sont essentiels. Notre etude a porte sur la modelisation de l’hypercholesterolemie familiale, et sur l’etablissement d’un protocole de differenciation des cellules souches pluripotentes en cholangiocytes fonctionnels.

2.3.1AbstractThe mammary gland is a complex organ, structured in a ramified epithelium supported by the stroma. The epithelium’s functional unit is the bilayered acinus, made of a layer of luminal cells surrounded by a layer of basal cells mainly composed of myoepithelial cells. The aim of this study was to develop a reproducible and manipulable three-dimensional co-culture model of the bilayered acinusin vitroto study the interactions between the two layers. Two different combinations of cell lines were co-cultured in Matrigel: SCp2 and SCg6 mice cells, or MCF-12A and Hs 578Bst human cell lines. Cell ratios and Matrigel concentration were optimized. The resulting acini were analysed by confocal microscopy using epithelial (E-cadherin) and myoepithelial (α-smooth muscle actin) markers. SCp2 and SCg6 cells formed distinct three-dimensional structures, whereas MCF-12A and Hs 578Bst cells formed some bilayered acini. Thisin vitrobilayered acini model will allow us to understand the role of interactions between luminal and myoepithelial cells in the normal breast development.