Recreating tumour complexity in a dish: Organoid models to study liver cancer cells and their extracellular environment

Primary liver cancer, consisting predominantly of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), remains one of the most lethal malignancies worldwide. This high malignancy is related to the complex and dynamic interactions between tumour cells, stromal cells and the extracellular environment. Novel in vitro models that can recapitulate the tumour are essential in increasing our understanding of liver cancer. Herein, primary liver cancer-derived organoids have opened up new avenues due to their patient-specificity, self-organizing ability and potential recapitulation of many of the tumour properties. Organoids are solely of epithelial origin, but incorporation into co-culture models can enable the investigation of the cellular component of the tumour microenvironment. However, the extracellular component also plays a vital role in cancer progression and representation is lacking within current in vitro models. In this review, organoid technology is discussed in the context of liver cancer models through comparisons to other cell culture systems. In addition, the role of the tumour extracellular environment in primary live

IL-21 receptor antagonist inhibits differentiation of B cells toward plasmablasts upon alloantigen stimulation

Interaction between T follicular helper (Tfh) cells and B cells is complex and involves various pathways, including the production of IL-21 by the Tfh cells. Secretion of IL-21 results in B cell differentiation toward immunoglobulin-producing plasmablasts. In patients after kidney transplantation, the formation of alloantibodies produced by donor antigen-activated B cells are a major cause of organ failure. In this allogeneic response, the role of IL-21-producing Tfh cells that regulate B cell differentiation is unknown. Here, we tested, in an alloantigen-driven setting, whether Tfh cell help signals control B cell differentiation with its dependency on IL-21. Pre-transplantation patient PBMCs were sorted into pure CD4posCXCR5pos Tfh cells and CD19posCD27pos memory B cells and stimulated with donor antigen in the presence or absence of an IL-21 receptor (IL-21R) antagonist (αIL-21R). Donor antigen stimulation initiated expression of the activation markers inducible co-stimulator (ICOS) and programmed death 1 (PD-1) on Tfh cells and a shift toward a mixed Tfh2 and Tfh17 phenotype. The memory B cells underwent class switch recombination and differentiated toward IgM- and IgG-producing plasmablasts. In the presence of αIL-21R, a dose-dependent inhibition of STAT3 phosphorylation was measured in both T and B cells. Blockade of the IL-21R did not have an effect on PD-1 and ICOS expression on Tfh cells but significantly inhibited B cell differentiation. The proportion of plasmablasts decreased by 78% in the presence of αIL-21R. Moreover, s

Use of Serum MicroRNAs as Biomarker for Hepatobiliary Diseases in Dogs

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Necroptotic Cell Death in Liver Transplantation and Underlying Diseases: Mechanisms and Clinical Perspective

Cell death is a natural process for the turnover of aged cells, but it can also arise as a result of pathological conditions. Cell death is recognized as a key feature in both acute and chronic hepatobiliary diseases caused by drug, alcohol, and fat uptake; by viral infection; or after surgical intervention. In the case of chronic disease, cell death can lead to (chronic) secondary inflammation, cirrhosis, and the progression to liver cancer. In liver transplantation, graft preservation and ischemia/reperfusion injury are associated with acute cell death. In both cases, so-called programmed cell death modalities are involved. Several distinct types of programmed cell death have been described of which apoptosis and necroptosis are the most well known. Parenchymal liver cells, including hepatocytes and cholangiocytes, are susceptible to both apoptosis and necroptosis, which are triggered by distinct signal transduction pathways. Apoptosis is dependent on a proteolytic cascade of caspase enzymes, whereas necroptosis induction is caspase-independent. Moreover, different from the “silent” apoptotic cell death, necroptosis can cause a secondary inflammatory cascade, so-called necroinflammation, triggered by the release of various damage-associated molecular patterns (DAMPs). These DAMPs activate the innate immune system, leading to both local and systemic inflammatory responses, which can even cause remote organ failure. Therapeutic targeting of necroptosis by pharmacological inhibitors, such as necrostatin-1, shows variable effects in different disease models

Prevention of postoperative delirium in elderly patients planned for elective surgery: systematic review and meta-analysis

Introduction: Vulnerable or “frail” patients are susceptible to the development of delirium when exposed to triggers such as surgical procedures. Once delirium occurs, interventions have little effect on severity or duration, emphasizing the importance of primary prevention. This review provides an overview of interventions to prevent postoperative delirium in elderly patients undergoing elective surgery. Methods: A literature search was conducted in March 2018. Randomized controlled trials (RCTs) and before-and-after studies on interventions with potential effects on postoperative delirium in elderly surgical patients were included. Acute admission, planned ICU admission, and cardiac patients were excluded. Full texts were reviewed, and quality was assessed by two independent reviewers. Primary outcome was the incidence of delirium. Secondary outcomes were severity and duration of delirium. Pooled risk ratios (RRs) were calculated for incidences of delirium where similar intervention techniques were used. Results: Thirty-one RCTs and four before-and-after studies were included for analysis. In 19 studies, intervention decreased the incidences of postoperative delirium. Severity was reduced in three out of nine studies which reported severity of delirium. Duration was reduced in three out of six studies. Pooled analysis showed a significant reduction in delirium incidence for dexmedetomidine treatment, and bispectral index (BIS)-guided anaesthesia. Based on sensitivity analyses, by leaving out studies with a high risk of bias, multicomponent interventions and antipsychotics can also significantly reduce the incidence of delirium. Conclusion: Multicomponent interventions, the use of antipsychotics, BIS-guidance, and dexmedetomidine treatment can successfully reduce the incidence of postoperative delirium in elderly patients undergoing elective, non-cardiac surgery. However, present studies are heterogeneous, and high-quality studies are scarce. Future studies should add these preventive methods to already existing multimodal and multidisciplinary interventions to tackle as many precipitating factors as possible, starting in the pre-admission period

Cell-free microRNAs as early predictors of graft viability during ex vivo normothermic machine perfusion of human donor livers

Background: Cell-free microRNAs (miRs) have emerged as early and sensitive biomarkers for tissue injury and function. This study aimed to investigate whether the release of hepatocyte-derived microRNAs (HDmiRs) and cholangiocyte-derived miRs (CDmiRs) correlates with hepato-cholangiocellular injury and function during oxygenated, normothermic machine perfusion (NMP) of human liver grafts. Methods: Donor livers (n = 12), declined for transplantation, were subjected to oxygenated NMP (6 hours) after a period of static cold storage (median 544 minutes (IQR 421-674)). Perfusate and bile samples were analyzed by qRT-PCR for HDmiR-122 and CDmiR-222. Spearman correlations were performed between miR levels and currently available indicators and classic markers. Results: Both HDmiR-122 and CDmiR-222 levels in perfusate at 30 minutes of NMP strongly correlated with hepatocyte injury (peak perfusate AST) and cholangiocyte injury (peak biliary LDH). In bile, only CDmiR-222 correlated with these injury markers. For hepato-cholangiocellular function, both miRs in perfusate correlated with total bilirubin, while HDmiR-122 (in perfusate) and CDmiR-222 (in bile) correlated with bicarbonate secretion. Both the relative ratio of HDmiR-122/CDmiR-222 and AST in perfusate at 30 minutes significantly correlated with cumulative bile production, but only the relative ratio was predictive of histopathological injury after 6 hours NMP. Conclusion: Early levels of HDmiR-122 and CDmiR-222, in perfusate and/or bile, are predictive of excretory functions and hepato-cholangiocellular injury after 6 hours NMP. These miRs may represent new biomarkers for graft viability and function during machine perfusion

Association of circulating microRNA-122 and microRNA-29a with stage of fibrosis and progression of chronic hepatitis in Labrador Retrievers

Background: Chronic hepatitis (CH) in dogs is common and has the tendency to progress to liver cirrhosis (LC). Circulating microRNAs might have the potential as markers for disease progression. Objectives: To investigate whether concentration of specific microRNAs in serum correlate with the stage and grade of CH in Labrador Retrievers. Animals: Twenty-two Labrador Retrievers with histological CH (n = 8), LC (n = 7), and normal liver (NL, n = 7). Methods: In this retrospective study, serum concentrations of miR-122, miR-29a, miR-133a, miR-181b, and miR-17-5p were measured by quantitative real-time PCR and evaluated using univariate linear regression in dogs. A multivariate model was fit including the grade of hepatitis and the stage of fibrosis. Results: Of the 5 microRNAs, only circulating miR-122 and miR-29a were significantly associated with the grade of hepatitis and the stage of fibrosis. A positive correlation was identified between the grade of hepatitis with miR-122 (rs = 0.79, P <.001) and miR-29a (rs = 0.78, P <.001). Both miR-122 (rs = 0.81, P <.001) and miR-29a (rs = 0.67, P <.001) showed a significant positive correlation with the stage of fibrosis. MiR-122 concentrations were significantly higher in the CH (P <.01) and LC groups (P <.001) compared to the NL group. MiR-29a concentrations w

Cellulose Nanofibril Hydrogel Promotes Hepatic Differentiation of Human Liver Organoids

To replicate functional liver tissue in vitro for drug testing or transplantation, 3D tissue engineering requires representative cell models as well as scaffolds that not only promote tissue production but also are applicable in a clinical setting. Recently, adult liver-derived liver organoids are found to be of much interest due to their genetic stability, expansion potential, and ability to differentiate toward a hepatocyte-like fate. The current standard for culturing these organoids is a basement membrane hydrogel like Matrigel (MG), which is derived from murine tumor material and apart from its variability and high costs, possesses an undefined composition and is therefore not clinically applicable. Here, a cellulose nanofibril (CNF) hydrogel is investigated with regard to its potential to serve as an alternative clinical grade scaffold to differentiate liver organoids. The re