5 research outputs found
Reconstruction of the mouse extrahepatic biliary tree using primary human extrahepatic cholangiocyte organoids
Treatment of common bile duct disorders such as biliary atresia or ischaemic strictures is limited to liver transplantation or hepatojejunostomy due to the lack of suitable tissue for surgical reconstruction. Here, we report a novel method for the isolation and propagation of human cholangiocytes from the extrahepatic biliary tree and we explore the potential of bioengineered biliary tissue consisting of these extrahepatic cholangiocyte organoids (ECOs) and biodegradable scaffolds for transplantation and biliary reconstruction in vivo. ECOs closely correlate with primary cholangiocytes in terms of transcriptomic profile and functional properties (ALP, GGT). Following transplantation in immunocompromised mice ECOs self-organize into tubular structures expressing biliary markers (CK7). When seeded on biodegradable scaffolds, ECOs form tissue-like structures retaining biliary marker expression (CK7) and function (ALP, GGT). This bioengineered tissue can reconstruct the wall of the biliary tree (gallbladder) and rescue and extrahepatic biliary injury mouse model following transplantation. Furthermore, it can be fashioned into bioengineered ducts and replace the native common bile duct of immunocompromised mice, with no evidence of cholestasis or lumen occlusion up to one month after reconstruction. In conclusion, ECOs can successfully reconstruct the biliary tree following transplantation, providing proof-of-principle for organ regeneration using human primary cells expanded in vitro
Cholangiocytes derived from human induced pluripotent stem cells for disease modeling and drug validation
The study of biliary disease has been constrained by a lack of primary human cholangiocytes. Here we present an efficient, serum-free protocol for directed differentiation of human induced pluripotent stem cells into cholangiocyte-like cells (CLCs). CLCs show functional characteristics of cholangiocytes, including bile acids transfer, alkaline phosphatase activity, γ-glutamyl-transpeptidase activity and physiological responses to secretin, somatostatin and vascular endothelial growth factor. We use CLCs to model in vitro key features of Alagille syndrome, polycystic liver disease and cystic fibrosis (CF)-associated cholangiopathy. Furthermore, we use CLCs generated from healthy individuals and patients with polycystic liver disease to reproduce the effects of the drugs verapamil and octreotide, and we show that the experimental CF drug VX809 rescues the disease phenotype of CF cholangiopathy in vitro. Our differentiation protocol will facilitate the study of biological mechanisms controlling biliary development, as well as disease modeling and drug screening
A hybrid bondline concept for bonded composite joints
Based on the experience in the past and the occurrence of in-service damages, the authorities restrict today the application of adhesive bonding of composite structures for aircraft applications. However, certification limitations can be overcome if occurring disbonds within a bond are stopped by implemented design features, so called disbond stopping features. Consequently, a novel bondline architecture for bonded composite joints is proposed. By implementing a distinct rather ductile thermoplastic phase, a physical barrier for growing disbonds is obtained and thus a fail-safe design, respectively. Moreover, the joint is established by using two different joining technologies, namely adhesive bonding and thermoset composite welding. A sophisticated manufacturing technique is developed for the hybrid bondline concept to achieve a high strength joint. The joint's quality is examined by means of several analytical methods like microsections, scanning electron microscopy (SEM), and energy-dispersive X-Ray (EDX) analysis. Additionally, the mechanical performance is evaluated by static Double Cantilever Beam (DCB) and Single Lap Shear (SLS) tests
Patient Age, Sex, and Inflammatory Bowel Disease Phenotype Associate With Course of Primary Sclerosing Cholangitis
Background & Aims Primary sclerosing cholangitis (PSC) is an orphan hepatobiliary disorder associated with inflammatory bowel disease (IBD). We aimed to estimate the risk of disease progression based on distinct clinical phenotypes in a large international cohort of patients with PSC. Methods We performed a retrospective outcome analysis of patients diagnosed with PSC from 1980 through 2010 at 37 centers in Europe, North America, and Australia. For each patient, we collected data on sex, clinician-reported age at and date of PSC and IBD diagnoses, phenotypes of IBD and PSC, and date and indication of IBD-related surgeries. The primary and secondary endpoints were liver transplantation or death (LTD) and hepatopancreatobiliary malignancy, respectively. Cox proportional hazards models were applied to determine the effects of individual covariates on rates of clinical events, with time-to-event analysis ascertained through Kaplan-Meier estimates. Results Of the 7121 patients in the cohort, 2616 met the primary endpoint (median time to event of 14.5 years) and 721 developed hepatopancreatobiliary malignancy. The most common malignancy was cholangiocarcinoma (n = 594); patients of advanced age at diagnosis had an increased incidence compared with younger patients (incidence rate: 1.2 per 100 patient-years for patients younger than 20 years old, 6.0 per 100 patient-years for patients 21–30 years old, 9.0 per 100 patient-years for patients 31–40 years old, 14.0 per 100 patient-years for patients 41–50 years old, 15.2 per 100 patient-years for patients 51–60 years old, and 21.0 per 100 patient-years for patients older than 60 years). Of all patients with PSC studied, 65.5% were men, 89.8% had classical or large-duct disease, and 70.0% developed IBD at some point. Assessing the development of IBD as a time-dependent covariate, Crohn's disease and no IBD (both vs ulcerative colitis) were associated with a lower risk of LTD (unadjusted hazard ratio [HR], 0.62; P <.001 and HR, 0.90; P =.03, respectively) and malignancy (HR, 0.68; P =.008 and HR, 0.77; P =.004, respectively). Small-duct PSC was associated with a lower risk of LTD or malignancy compared with classic PSC (HR, 0.30 and HR, 0.15, respectively; both P <.001). Female sex was also associated with a lower risk of LTD or malignancy (HR, 0.88; P =.002 and HR, 0.68; P <.001, respectively). In multivariable analyses assessing the primary endpoint, small-duct PSC characterized a low-risk phenotype in both sexes (adjusted HR for men, 0.23; P <.001 and adjusted HR for women, 0.48; P =.003). Conversely, patients with ulcerative colitis had an increased risk of liver disease progression compared with patients with Crohn's disease (HR, 1.56; P <.001) or no IBD (HR, 1.15; P =.002). Conclusions In an analysis of data from individual patients with PSC worldwide, we found significant variation in clinical course associated with age at diagnosis, sex, and ductal and IBD subtypes. The survival estimates provided might be used to estimate risk levels for patients with PSC and select patients for clinical trials
The EASL-Lancet Liver Commission: protecting the next generation of Europeans against liver disease complications and premature mortality
Liver diseases have become a major health threat across
Europe, and the face of European hepatology is changing
due to the cure of viral hepatitis C and the control of
chronic viral hepatitis B, the increasingly widespread
unhealthy use of alcohol, the epidemic of obesity, and
undiagnosed or untreated liver disease in migrant
populations. Consequently, Europe is facing a looming
syndemic, in which socioeconomic and health inequities
combine to adversely affect liver disease prevalence,
outcomes, and opportunities to receive care. In addition,
the COVID-19 pandemic has magnified pre-existing
challenges to uniform implementation of policies and
equity of access to care in Europe, arising from national
borders and the cultural and historical heterogeneity of
European societies. In following up on work from
the Lancet Commission on liver disease in the UK and
epidemiological studies led by the European Association
for the Study of the Liver (EASL), our multidisciplinary
Commission, comprising a wide range of public health,
medical, and nursing specialty groups, along with
patient representatives, set out to provide a snapshot of
the European landscape on liver diseases and to propose
a framework for the principal actions required to
improve liver health in Europe. We believe that a joint
European process of thinking, and construction of
uniform policies and action, implementation, and
evaluation can serve as a powerful mechanism to
improve liver care in Europe and set the way for similar
changes globally.
On the basis of these data, we present ten actionable
recommendations, half of which are oriented towards
health-care providers and half of which focus primarily
on health policy. A fundamental shift must occur, in
which health promotion, prevention, proactive casefinding, early identification of progressive liver fibrosis,
and early treatment of liver diseases replace the current
emphasis on the management of end-stage liver disease
complications. A considerable focus should be put on
underserved and marginalised communities, including
early diagnosis and management in children, and we
provide proposals on how to better target disadvantaged
communities through health promotion, prevention, and
care using multilevel interventions acting on current
barriers.
Underlying this transformative shift is the need to
enhance awareness of the preventable and treatable
nature of many liver diseases. Therapeutic nihilism,
which is prevalent in current clinical practice across a
range of medical specialities as well as in many patients
themselves, has to end. We wish to challenge medical
specialty protectionism and invite a broad range of
stakeholders, including primary care physicians, nurses,
patients, peers, and members of relevant communities,
along with medical specialists trained in obesity, diabetes,
liver disease, oncology, cardiovascular disease, public
health, addictions, infectious diseases, and more, to
engage in integrated person-centred liver patient care
across classical medical specialty boundaries. This shift
includes a revision in how we converse about liver
disease and speak with our patients, and a reappraisal of
disease-related medical nomenclature conducted to
increase awareness and reduce the social stigmatisation
associated with liver disease.
Reimbursement mechanisms and insurance systems
must be harmonised to account for patient-centric,
multimorbidity models of care across a range of medical
specialties, and the World Health Assembly resolution
to improve the transparency and fairness of market
prices for medicines throughout Europe should be
reinforced. Finally, we outline how Europe can move
forward with implementation of effective policy action
on taxation, food reformulation, and product labelling,
advertising, and availability, similar to that implemented
for tobacco, to reduce consumption of alcohol, ultraprocessed foods, and foods with added sugar, especially
among young people. We should utilise the window of
opportunity created by the COVID-19 pandemic to
overcome fragmentation and the variability of health
prevention policies and research across Europe. We
argue that the liver is a window to the 21st-century
health of the European population. Through our
proposed syndemic approach to liver disease and social
and health inequities in Europe, the liver will serve as a
sentinel for improving the overall health of European
populations