Von willebrand and factor VIII portosystemic circulation gradient in cirrhosi. Implications for portal vein thrombosis

OBJECTIVES: Portal vein thrombosis seems to be dependent on local hypercoagulation and venous stasis; data regarding endothelial damage are lacking. METHODS: von Willebrad factor, a marker of endothelial damage/perturbation, factor VIII, and lipopolysaccharides (LPS) were studied in the portal and systemic circulation of 20 cirrhotic patients undergoing transjugular intrahepatic portosystemic procedure. RESULTS: von Willebrad factor, factor VIII, and LPS were higher in the portal compared with systemic circulation, with a significant correlation between LPS and the other 2 variables. DISCUSSION: Endothelial damage and hypercoagulation coexist in the portal tree of patients with cirrhosis, and both could contribute to portal vein thrombosis. LPS may be a potential trigger of endothelial damage

Tracing tumorigenesis in a solid tumor model at single-cell resolution

Characterizing the complex composition of solid tumors is fundamental for understanding tumor initiation, progression and metastasis. While patient-derived samples provide valuable insight, they are heterogeneous on multiple molecular levels, and often originate from advanced tumor stages. Here, we use single-cell transcriptome and epitope profiling together with pathway and lineage analyses to study tumorigenesis from a developmental perspective in a mouse model of salivary gland squamous cell carcinoma. We provide a comprehensive cell atlas and characterize tumor-specific cells. We find that these cells are connected along a reproducible developmental trajectory: initiated in basal cells exhibiting an epithelial-to-mesenchymal transition signature, tumorigenesis proceeds through Wnt-differential cancer stem cell-like subpopulations before differentiating into luminal-like cells. Our work provides unbiased insights into tumor-specific cellular identities in a whole tissue environment, and emphasizes the power of using defined genetic model systems

Single-cell RNA-sequencing of herpes simplex virus 1-infected cells connects NRF2 activation to an antiviral program

Herpesvirus infection initiates a range of perturbations in the host cell, which remain poorly understood at the level of individual cells. Here, we quantify the transcriptome of single human primary fibroblasts during the first hours of lytic infection with HSV-1. By applying a generalizable analysis scheme, we define a precise temporal order of early viral gene expression and propose a set-wise emergence of viral genes. We identify host cell genes and pathways relevant for infection by combining three different computational approaches: gene and pathway overdispersion analysis, prediction of cell-state transition probabilities, as well as future cell states. One transcriptional program, which correlates with increased resistance to infection, implicates the transcription factor NRF2. Consequently, Bardoxolone methyl and Sulforaphane, two known NRF2 agonists, impair virus production, suggesting that NRF2 activation restricts viral infection. Our study provides insights into early stages of HSV-1 infection and serves as a general blueprint for the investigation of heterogeneous cell states in virus infection

Role of portal venous platelet activation in patients with decompensated cirrhosis and TIPS

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Differential inflammasome activation predisposes to acute-on-chronic liver failure in human and experimental cirrhosis with and without previous decompensation

OBJECTIVE Systemic inflammation predisposes acutely decompensated (AD) cirrhosis to the development of acute-on-chronic liver failure (ACLF). Supportive treatment can improve AD patients, becoming recompensated. Little is known about the outcome of patients recompensated after AD. We hypothesise that different inflammasome activation is involved in ACL F development in compensated and recompensated patients. DESIGN 249 patients with cirrhosis, divided into compensated and recompensated (previous AD), were followed prospectively for fatal ACL F development. Two external cohorts (n=327) (recompensation, AD and ACL F) were included. Inflammasome-driving interleukins (ILs), IL-1α (caspase-4/11-dependent) and IL-1β (caspase-1- dependent), were measured. In rats, bile duct ligationinduced cirrhosis and lipopolysaccharide exposition were used to induce AD and subsequent recompensation. IL-1α and IL-1β levels and upstream/downstream gene expression were measured. RESULTS Patients developing ACL F showed higher baseline levels of ILs. Recompensated patients and patients with detectable ILs had higher rates of ACL F development than compensated patients. Baseline CLIF-­C (European Foundation for the study of chronic liver failure consortium) AD, albumin and IL-1α were independent predictors of ACL F development in compensated and CLIF-­C AD and IL-1β in recompensated patients. Compensated rats showed higher IL-1α gene expression and recompensated rats higher IL-1β levels with higher hepatic gene expression. Higher IL-1β detection rates in recompensated patients developing ACL F and higher IL-1α and IL-1β detection rates in patients with ACL F were confirmed in the two external cohorts. CONCLUSION Previous AD is an important risk factor for fatal ACL F development and possibly linked with inflammasome activation. Animal models confirmed the results showing a link between ACL F development and IL-1α in compensated cirrhosis and IL-1β in recompensated cirrhosi

Total area of spontaneous portosystemic shunts independently predicts hepatic encephalopathy and mortality in liver cirrhosis

BACKGROUND: Spontaneous portosystemic shunts (SPSS) frequently develop in liver cirrhosis. Recent data suggested that presence of a single large SPSS is associated with complications, especially overt hepatic encephalopathy (oHE). However, presence of >1 SPSS is common. This study evaluates the impact of total cross-sectional SPSS area (TSA) on outcome of patients with liver cirrhosis. METHODS: In this retrospective international multicentric study, computed tomography (CT) scans of 908 cirrhotic patients with SPSS were evaluated for TSA. Clinical and laboratory data were recorded. Each detected SPSS radius was measured and TSA calculated. 1-year survival was primary and acute decompensation (oHE, variceal bleeding, ascites) secondary endpoint. RESULTS: 301 patients (169 male) were included in the training cohort. 30% of all patients presented >1 SPSS. TSA cut-off of 83 mm2 was determined to classify patients with small or large TSA (S-/L-TSA). L-TSA patients presented higher MELD (11 vs. 14) and more commonly history of oHE (12% vs. 21%, p83mm2 increases the risk for oHE and mortality in liver cirrhosis. Our results may have impact on clinical use of TSA/SPSS for risk stratification and clinical decision-making considering management of SPSS

The PREDICT study uncovers three clinical courses of acutely decompensated cirrhosis that have distinct pathophysiology

Background & Aims: Acute decompensation (AD) of cirrhosis is defined as the acute development of ascites, gastrointestinal hemorrhage, hepatic encephalopathy, infection or any combination thereof, requiring hospitalization. The presence of organ failure(s) in patients with AD defines acute-on-chronic liver failure (ACLF). The PREDICT study is a European, prospective, observational study, designed to characterize the clinical course of AD and to identify predictors of ACLF. Methods: A total of 1,071 patients with AD were enrolled. We collected detailed pre-specified information on the 3-month period prior to enrollment, and clinical and laboratory data at enrollment. Patients were then closely followed up for 3 months. Outcomes (liver transplantation and death) at 1 year were also recorded. Results: Three groups of patients were identified. Pre-ACLF patients (n = 218) developed ACLF and had 3-month and 1-year mortality rates of 53.7% and 67.4%, respectively. Unstable decompensated cirrhosis (UDC) patients (n = 233) required ≥1 readmission but did not develop ACLF and had mortality rates of 21.0% and 35.6%, respectively. Stable decompensated cirrhosis (SDC) patients (n = 620) were not readmitted, did not develop ACLF and had a 1-year mortality rate of only 9.5%. The 3 groups differed significantly regarding the grade and course of systemic inflammation (high-grade at enrollment with aggravation during follow-up in pre-ACLF; low-grade at enrollment with subsequent steady-course in UDC; and low-grade at enrollment with subsequent improvement in SDC) and the prevalence of surrogates of severe portal hypertension throughout the study (high in UDC vs. low in pre-ACLF and SDC). Conclusions: Acute decompensation without ACLF is a heterogeneous condition with 3 different clinical courses and 2 major pathophysiological mechanisms: systemic inflammation and portal hypertension. Predicting the development of ACLF remains a major future challenge. ClinicalTrials.gov number: NCT03056612. Lay summary: Herein, we describe, for the first time, 3 different clinical courses of acute decompensation (AD) of cirrhosis after hospital admission. The first clinical course includes patients who develop acute-on-chronic liver failure (ACLF) and have a high short-term risk of death – termed pre-ACLF. The second clinical course (unstable decompensated cirrhosis) includes patients requiring frequent hospitalizations unrelated to ACLF and is associated with a lower mortality risk than pre-ACLF. Finally, the third clinical course (stable decompensated cirrhosis), includes two-thirds of all patients admitted to hospital with AD – patients in this group rarely require hospital admission and have a much lower 1-year mortality risk

Transcriptomic profiling of SARS-CoV-2 infected human cell lines identifies HSP90 as target for COVID-19 therapy

Detailed knowledge of the molecular biology of SARS-CoV-2 infection is crucial for understanding of viral replication, host responses and disease progression. Here, we report gene expression profiles of three SARS-CoV and SARS-CoV-2 infected human cell lines. SARS-CoV-2 elicited an approximately two-fold higher stimulation of the innate immune response compared to SARS-CoV in the human epithelial cell line Calu-3, including induction of miRNA-155. Single-cell RNA sequencing of infected cells showed that genes induced by virus infections were broadly upregulated, whereas interferon beta/lambda genes an pro-inflammatory cytokines such as IL-6 were expressed only in small subsets of infected cells. Temporal analysis suggested that transcriptional activities of interferon regulatory factors precede those of nuclear factor κB. Lastly, we identified heat shock protein 90 (HSP90) as a protein relevant for the infection. Inhibition of the HSP90 activity resulted in a reduction of viral replication and pro-inflammatory cytokine expression in primary human airway epithelial cells

Live-attenuated vaccine sCPD9 elicits superior mucosal and systemic immunity to SARS-CoV-2 variants in hamsters

Vaccines play a critical role in combating the COVID-19 pandemic. Future control of the pandemic requires improved vaccines with high efficacy against newly emerging SARS-CoV-2 variants and the ability to reduce virus transmission. Here we compare immune responses and preclinical efficacy of the mRNA vaccine BNT162b2, the adenovirus-vectored spike vaccine Ad2-spike and the live-attenuated virus vaccine candidate sCPD9 in Syrian hamsters, using both homogeneous and heterologous vaccination regimens. Comparative vaccine efficacy was assessed by employing readouts from virus titrations to single-cell RNA sequencing. Our results show that sCPD9 vaccination elicited the most robust immunity, including rapid viral clearance, reduced tissue damage, fast differentiation of pre-plasmablasts, strong systemic and mucosal humoral responses, and rapid recall of memory T cells from lung tissue after challenge with heterologous SARS-CoV-2. Overall, our results demonstrate that live-attenuated vaccines offer advantages over currently available COVID-19 vaccines