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1.
United European Gastroenterol J ; 12(4): 516-525, 2024 May.
Article in English | MEDLINE | ID: mdl-38520063

ABSTRACT

BACKGROUND AND OBJECTIVE: The prevalence of Hepatitis Delta Virus (HDV) is underestimated and the assessment of fibrosis is recommended for this infection. We tested the diagnostic impact of an annual screening for HDV serology in Hepatitis B Surface Antigen (HBs Ag) chronic carriers and followed the progression of fibrosis in these patients. METHODS: Between January 2014 and October 2021, we annually tested all chronic HBs Ag-positive patients for HDV antibody (HDV Ab). Each HDV Ab positive patient underwent annually repeated elastometry. Patients with detectable HDV RNA levels (group 1) were compared to those with undetectable HDV RNA (group 2). RESULTS: We identified 610 chronic HBs Ag-positive patients, and repeated screening for HDV Ab was performed in 534 patients. Sixty (11%) patients were HDV Ab positive at baseline and were considered as "coinfected". Seven cases of HDV superinfection were diagnosed through repeated screening. In co-infected patients, cirrhosis was initially diagnosed in 12/60 patients and developed in six patients during follow-up. HDV RNA PCR was performed in 57/67 patients and 27 had detectable levels (group 1). Cumulative incidence of cirrhosis at 7 years was 13.8% (95% CI 0-30) in group 1 and 0 (95% CI 0-0) in group 2 (p = 0.026). CONCLUSION: A systematic screening for HDV in chronic HB Ag carriers revealed a high prevalence of HDV Ab. Repeated serological screening enables the diagnosis of superinfections in asymptomatic patients. Regular assessment of fibrosis using elastometry leads to the identification of incidental cirrhosis in patients with detectable HDV RNA.


Subject(s)
Carrier State , Hepatitis B Surface Antigens , Hepatitis B, Chronic , Hepatitis D , Hepatitis Delta Virus , Liver Cirrhosis , Mass Screening , Humans , Liver Cirrhosis/virology , Liver Cirrhosis/diagnosis , Male , Female , Hepatitis Delta Virus/genetics , Hepatitis Delta Virus/immunology , Hepatitis Delta Virus/isolation & purification , Hepatitis B, Chronic/complications , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/virology , Middle Aged , Hepatitis D/diagnosis , Hepatitis D/complications , Hepatitis D/epidemiology , Hepatitis B Surface Antigens/blood , Mass Screening/methods , Carrier State/diagnosis , Adult , RNA, Viral/blood , Coinfection/diagnosis , Disease Progression , Hepatitis Antibodies/blood , Prevalence , Elasticity Imaging Techniques , Aged , Incidence
2.
Nat Cell Biol ; 26(2): 250-262, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38321203

ABSTRACT

A key aspect of nutrient absorption is the exquisite division of labour across the length of the small intestine, with individual nutrients taken up at different proximal:distal positions. For millennia, the small intestine was thought to comprise three segments with indefinite borders: the duodenum, jejunum and ileum. By examining the fine-scale longitudinal transcriptional patterns that span the mouse and human small intestine, we instead identified five domains of nutrient absorption that mount distinct responses to dietary changes, and three regional stem cell populations. Molecular domain identity can be detected with machine learning, which provides a systematic method to computationally identify intestinal domains in mice. We generated a predictive model of transcriptional control of domain identity and validated the roles of Ppar-δ and Cdx1 in patterning lipid metabolism-associated genes. These findings represent a foundational framework for the zonation of absorption across the mammalian small intestine.


Subject(s)
Duodenum , Intestine, Small , Humans , Mice , Animals , Intestine, Small/metabolism , Duodenum/metabolism , Intestines , Jejunum/metabolism , Ileum/metabolism , Mammals
3.
bioRxiv ; 2023 Sep 22.
Article in English | MEDLINE | ID: mdl-37790430

ABSTRACT

A key aspect of nutrient absorption is the exquisite division of labor across the length of the small intestine, with individual classes of micronutrients taken up at different positions. For millennia, the small intestine was thought to comprise three segments with indefinite borders: the duodenum, jejunum, and ileum. By examining fine-scale longitudinal segmentation of the mouse and human small intestines, we identified transcriptional signatures and upstream regulatory factors that define five domains of nutrient absorption, distinct from the three traditional sections. Spatially restricted expression programs were most prominent in nutrient-absorbing enterocytes but initially arose in intestinal stem cells residing in three regional populations. While a core signature was maintained across mice and humans with different diets and environments, domain properties were influenced by dietary changes. We established the functions of Ppar-ẟ and Cdx1 in patterning lipid metabolism in distal domains and generated a predictive model of additional transcription factors that direct domain identity. Molecular domain identity can be detected with machine learning, representing the first systematic method to computationally identify specific intestinal regions in mice. These findings provide a foundational framework for the identity and control of longitudinal zonation of absorption along the proximal:distal small intestinal axis.

4.
Mucosal Immunol ; 16(6): 801-816, 2023 12.
Article in English | MEDLINE | ID: mdl-37659724

ABSTRACT

Cluster of differentiation (CD4+) T cells consist of multiple subtypes, defined by expression of lineage-specific transcription factors, that contribute to the control of infectious diseases by providing help to immune and nonimmune target cells. In the current study, we examined the role of B cell lymphoma (Bcl)-6, a transcriptional repressor and master regulator of T follicular helper cell differentiation, in T cell-mediated host defense against intestinal and systemic parasitic infections. We demonstrate that while Bcl-6 expression by CD4+ T cells is critical for antibody-mediated protective immunity against secondary infection with the nematode Heligmosoides polygyrus bakeri, it paradoxically compromises worm expulsion during primary infection by limiting the generation of interleukin-10 (IL-10)-producing Gata3+ T helper 2 cells. Enhanced worm expulsion in the absence of Bcl-6 expressing T cells was associated with amplified intestinal goblet cell differentiation and increased generation of alternatively activated macrophages, effects that were reversed by neutralization of IL-10 signals. An increase in IL-10 production by Bcl-6-deficient CD4+ T cells was also evident in the context of systemic Leishmania donovani infection, but in contrast to Heligmosoides polygyrus bakeri infection, compromised T helper 1-mediated liver macrophage activation and increased susceptibility to this distinct parasitic challenge. Collectively, our studies suggest that host defense pathways that protect against parasite superinfection and lethal systemic protozoal infections can be engaged at the cost of compromised primary resistance to well-tolerated helminths.


Subject(s)
Nematoda , Parasitic Diseases , Animals , Interleukin-10 , Th2 Cells
5.
United European Gastroenterol J ; 10(8): 874-887, 2022 10.
Article in English | MEDLINE | ID: mdl-36217553

ABSTRACT

BACKGROUND: Transjugular intrahepatic portosystemic shunt (TIPS) may be used as a salvage treatment in patients with cirrhosis and refractory variceal bleeding. AIM: To synthesize the available evidence on the efficacy of TIPS in patients with cirrhosis and refractory variceal bleeding. METHODS: Meta-analysis of trials evaluating TIPS in patients with cirrhosis and refractory variceal bleeding, including subgroup analysis to assess the impact of recent changes in the management of variceal bleeding (i.e., the use of Polytetrafluoroethylene-covered TIPS and the availability of pre-emptive TIPS as a first-line treatment for acute variceal bleeding). RESULTS: Twenty-three studies with 1430 patients were included. The pooled estimate rates were 0.33 (95% CI = 0.29-0.37) for death at 1 month-6 weeks, 0.46 (95% CI = 0.40-0.52) for death at 1 year, and 0.09 (95% CI = 0.06-0.11) for death due to rebleeding in the follow-up. The pooled estimate rates for death at 1 month or 6 weeks were similar in subgroup analyses including studies that did not use covered TIPS or that did not include patients after the pre-emptive TIPS area compared to the ones that did (pooled estimate rate 0.33 [95% CI = 0.28-0.38] and 0.32 [95% CI = 0.25-0.39], respectively). The pooled estimate rates were 0.16 (95% CI = 0.13-0.18) for rebleeding, 0.25 (95% CI = 0.17-0.36) for occurrence of hepatic encephalopathy, and 0.08 (95% CI = 0.05-0.13) for access to liver transplantation after TIPS insertion. CONCLUSIONS: One third of patients with cirrhosis and refractory variceal bleeding treated with salvage TIPS died within the first 6 weeks. Recent improvements in the management of variceal bleeding did not improve the survival of patients presenting with refractory variceal bleeding.


Subject(s)
Esophageal and Gastric Varices , Portasystemic Shunt, Transjugular Intrahepatic , Esophageal and Gastric Varices/diagnosis , Esophageal and Gastric Varices/etiology , Esophageal and Gastric Varices/surgery , Gastrointestinal Hemorrhage/diagnosis , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/surgery , Humans , Liver Cirrhosis/complications , Liver Cirrhosis/surgery , Polytetrafluoroethylene , Portasystemic Shunt, Transjugular Intrahepatic/adverse effects , Recurrence , Salvage Therapy
6.
J Hepatol ; 73(2): 303-314, 2020 08.
Article in English | MEDLINE | ID: mdl-32145259

ABSTRACT

BACKGROUND & AIMS: Severe forms of alcohol-related liver disease are associated with increased susceptibility to infections which are associated with poor prognosis. The cellular and molecular mechanisms responsible for this altered host defense are incompletely understood. METHODS: We performed whole blood phenotypic analysis and ex vivo stimulation with various pathogen-associated molecular patterns (PAMPs). We included 34 patients with alcohol-related cirrhosis (18 of whom had biopsy-proven severe alcoholic hepatitis [sAH]), 12 healthy controls and 11 patients with chronic alcohol consumption without significant liver disease. We also evaluated the transcriptomic (RNA-seq) and chromatin accessibility (ATAC-seq) profiles of CD14+ monocytes from a subset of patients. RESULTS: Circulating monocytes and conventional dendritic cells (DCs) from patients with sAH displayed complex alterations characterized by increased expression of both activating and inhibitory surface markers and an impaired pro-inflammatory response upon stimulation with PAMPs representative of gram-negative bacteria (lipopolysaccharide, Pam3CSK4) or fungal pathogens (Zymosan). Their decreased ability to produce more than 1 cytokine (polyfunctionality) upon PAMP stimulation correlated with the risk of developing infection at 28 days or mortality at 90 days. The presence of acute-on-chronic liver failure in patients with sAH did not significantly modify the immune profile of monocytes and DCs. Moreover, CD14+ monocytes of patients with sAH displayed altered transcriptional and epigenomic profiles characterized by downregulation of key innate immune and metabolic pathways and upregulation of important immunomodulatory factors. CONCLUSIONS: In patients with sAH, the altered transcriptional program and functional properties of monocytes that contribute to patients' susceptibility to infection have strong epigenetic determinants. LAY SUMMARY: Patients with severe alcoholic hepatitis are at increased risk of infections, which contribute to the poor prognosis associated with the disease. Herein, we show that epigenetic determinants underly the immune cell dysfunction and inappropriate responses to pathogens that are associated with severe alcoholic hepatitis.


Subject(s)
Cytokines/metabolism , Epigenesis, Genetic , Hepatitis, Alcoholic , Infections , Lipopolysaccharide Receptors/analysis , Monocytes/immunology , Biopsy/methods , Dendritic Cells/immunology , Disease Progression , Disease Susceptibility/epidemiology , Down-Regulation , Female , Gram-Negative Bacteria/isolation & purification , Hepatitis, Alcoholic/blood , Hepatitis, Alcoholic/immunology , Hepatitis, Alcoholic/mortality , Hepatitis, Alcoholic/pathology , Humans , Infections/epidemiology , Infections/microbiology , Liver/pathology , Male , Prognosis , Risk Assessment/methods
7.
Sci China Life Sci ; 61(10): 1205-1211, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30194677

ABSTRACT

The constant renewal of the intestinal epithelium is fueled by intestinal stem cells (ISCs) lying at the base of crypts, and these ISCs continuously give rise to transit-amplifying progenitor cells during homeostasis. Upon injury and loss of ISCs, the epithelium has the ability to regenerate by the dedifferentiation of progenitor cells that then regain stemness and repopulate the pool of ISCs. Epithelial cells receive cues from immune cells, mesenchymal cells and the microbiome to maintain homeostasis. This review focuses on the response of the epithelium to damage and the interplay between the different intestinal compartments.


Subject(s)
Cell Communication/physiology , Cell Proliferation/physiology , Epithelial Cells/cytology , Intestinal Mucosa/cytology , Stem Cells/cytology , Animals , Epithelial Cells/physiology , Gastrointestinal Microbiome/physiology , Homeostasis/physiology , Humans , Intestinal Mucosa/microbiology , Intestinal Mucosa/physiology , Regeneration/physiology , Stem Cells/physiology
8.
J Hepatol ; 69(2): 318-324, 2018 08.
Article in English | MEDLINE | ID: mdl-29524528

ABSTRACT

BACKGROUND & AIMS: A better identification of factors predicting death is needed in alcoholic hepatitis (AH). Acute-on-chronic liver failure (ACLF) occurs during the course of liver disease and can be identified when AH is diagnosed (prevalent ACLF [pACLF]) or during follow-up (incidental ACLF [iACLF]). This study analyzed the impact of ACLF on outcomes in AH and the role of infection on the onset of ACLF and death. METHODS: Patients admitted from July 2006 to July 2015 suffering from biopsy-proven severe (s)AH with a Maddrey discriminant function (mDF) ≥32 were included. Infectious episodes, ACLF, and mortality were assessed during a 168-day follow-up period. Results were validated on an independent cohort. RESULTS: One hundred sixty-five patients were included. Mean mDF was 66.3 ±â€¯20.7 and mean model for end-stage liver disease score was 26.8 ±â€¯7.4. The 28-day cumulative incidence of death (CID) was 31% (95% CI 24-39%). Seventy-nine patients (47.9%) had pACLF. The 28-day CID without pACLF and with pACLF-1, pACLF-2, and pACLF-3 were 10.4% (95% CI 5.1-18.0), 30.8% (95% CI 14.3-49.0), 58.3% (95% CI 35.6-75.5), and 72.4% (95% CI 51.3-85.5), respectively, p <0.0001. Twenty-nine patients (17.5%) developed iACLF. The 28-day relative risk of death in patients developing iACLF was 41.87 (95% CI 5.2-335.1; p <0.001). A previous infection was the only independent risk factor for developing iACLF during the follow-up. Prevalence, incidence, and impact on prognosis of ACLF were confirmed in a validation cohort of 97 patients with probable sAH. CONCLUSIONS: ACLF is frequent during the course of sAH and is associated with high mortality. Infection strongly predicts the development of ACLF in this setting. LAY SUMMARY: In patients with chronic liver disease, an acute deterioration of liver function combined with single or multiple organ failures is known as acute-on-chronic liver failure. This study shows that acute-on-chronic liver failure is frequent during the course of severe alcoholic hepatitis. In severe alcoholic hepatitis, acute-on-chronic liver failure is associated with high mortality and frequently occurs after an infection.


Subject(s)
Acute-On-Chronic Liver Failure , Hepatitis, Alcoholic , Infections , Acute-On-Chronic Liver Failure/diagnosis , Acute-On-Chronic Liver Failure/etiology , Acute-On-Chronic Liver Failure/mortality , Belgium/epidemiology , Female , Follow-Up Studies , Hepatitis, Alcoholic/complications , Hepatitis, Alcoholic/epidemiology , Humans , Infections/diagnosis , Infections/epidemiology , Male , Middle Aged , Mortality , Predictive Value of Tests , Prevalence , Prognosis , Risk Assessment/methods , Risk Factors , Severity of Illness Index
9.
Clin Exp Rheumatol ; 35(1): 129-136, 2017.
Article in English | MEDLINE | ID: mdl-27749214

ABSTRACT

OBJECTIVES: To determine the role of S100A8/A9 in the pathogenesis of primary Sjögren's syndrome (pSS). METHODS: The serum levels of S100A8/A9 were determined in pSS patients and healthy controls by ELISA. The expression of S100A8/A9 in salivary glands was assessed by immunohistochemistry. The phenotype of S100A8+ and S100A9+ cells was identified using double immunofluorescence. The effects of S100A8/A9 on cytokine production by peripheral blood mononuclear cells (PBMCs) from pSS patients were determined in vitro by flow cytometry. The effects of pro-inflammatory cytokines on S100A8/A9 secretion were additionally investigated in vitro by ELISA in PBMCs from pSS patients and control subjects. RESULTS: Serum levels of S100A8/A9 were significantly increased in pSS patients compared to healthy controls. The tissular expression of S100A8 and S100A9, identified in professional phagocytes (neutrophils, monocytes and plasmacytoid dendritic cells), was increased in the salivary glands of pSS patients and correlated with focus score. In vitro, recombinant S100A8/A9 increased the production of IL-1ß, IL-6, TNF-α, IFN-γ, IL-10, IL-17A and IL-22 by PBMCs. The S100A8/A9-induced increase in TNF-α production in pSS patients was significant relative to controls. Furthermore, IL-1ß, TNF-α, IL-6, and IL-17A stimulated release of S100A8/A9 from PBMCs in pSS patients. CONCLUSIONS: S100A8/A9 is increased in pSS patients contributing to the in vitro increased production of pro-inflammatory cytokines. As such, S100A8/A9 in concert with other cytokines might contribute to the pathogenesis of pSS.


Subject(s)
Calgranulin A/metabolism , Calgranulin B/metabolism , Cytokines/metabolism , Phagocytes/metabolism , Salivary Glands/metabolism , Sjogren's Syndrome/metabolism , Up-Regulation , Calgranulin A/blood , Calgranulin B/blood , Cytokines/pharmacology , Female , Humans , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/metabolism , Male , Middle Aged , Phagocytes/cytology , Phagocytes/drug effects , Sjogren's Syndrome/blood
10.
Semin Liver Dis ; 36(2): 174-80, 2016 05.
Article in English | MEDLINE | ID: mdl-27172360

ABSTRACT

In this review to the authors provide evidence-based definitions of organ failure in patients with acute decompensation of cirrhosis, describe the prevalence and prognostic impact of organ failure in these patients, and highlight current knowledge of the mechanisms responsible for its development. Excessive inflammatory response and a reduction of the capacity of organs to respond adequately to stress may sensitize cirrhotic patients to inflammation-driven organ damage and failure. The dynamic evolution of organ failure during early intensive management may provide a useful tool for guiding subsequent management strategies, or in some cases, for defining the futility of care. Currently, management of patients with acute-on-chronic liver failure is mainly supportive. Understanding the mechanisms of immunopathology and failed organ tolerance in acute decompensated cirrhosis could open new areas of research and define new therapeutic options in this life-threatening condition.


Subject(s)
Acute-On-Chronic Liver Failure/immunology , Inflammation/immunology , Multiple Organ Failure/immunology , Organ Dysfunction Scores , Acute Kidney Injury/complications , Acute-On-Chronic Liver Failure/complications , Hepatic Encephalopathy/complications , Humans , Liver Cirrhosis/complications , Severity of Illness Index
11.
Clin J Am Soc Nephrol ; 6(11): 2573-8, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21921153

ABSTRACT

BACKGROUND AND OBJECTIVES: In 2009, the pandemic influenza A/H1N1 accounted for worldwide recommendations about vaccination. There are few data concerning the immunogenicity or the security of the adjuvanted-A/H1N1 vaccine in transplanted and hemodialyzed patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Sera from 21 controls, 53 hemodialyzed (HD) patients, and 111 renal transplant recipients (RT) were sampled before (T0) and 1 month after (T1) a single dose of Pandemrix® vaccine (GSK Biologicals, AS03-adjuvanted). We measured the neutralizing antibodies against A/H1N1/2009, the geometric mean (GM) titers, the GM titer ratios (T1/T0) with 95% confidence intervals, and the seroconversion rate (responders: ≥4-fold increase in titer). The HLA and MICA immunization was determined by Luminex technology. RESULTS: The GM titer ratio was 38 (19 to 78), 9 (5 to 16), and 5 (3 to 6) for controls, HD patients, and RT patients, respectively (P < 0.001). The proportion of responders was 90%, 57%, and 44%, respectively (P < 0.001). In RT patients, the prevalence of histocompatibility leukocyte antigen (HLA) class I, histocompatibility leukocyte antigen class II, and MHC class I-related chain A immunization, was, respectively, 15%, 14%, and 14% before and 14%, 14%, and 11% after vaccination (P = 1, 1, and 0.39). CONCLUSIONS: The influenza A/H1N1-adjuvanted vaccine is of limited efficacy but is safe in renal disease populations. The humoral response is lower in transplanted versus hemodialyzed patients. Further studies are needed to improve the efficacy of vaccination in those populations.


Subject(s)
Influenza A Virus, H1N1 Subtype/immunology , Influenza Vaccines/administration & dosage , Influenza, Human/prevention & control , Kidney Failure, Chronic/therapy , Kidney Transplantation , Renal Dialysis , Adult , Aged , Analysis of Variance , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Belgium , Case-Control Studies , Chi-Square Distribution , Cohort Studies , Drug Combinations , Female , Histocompatibility Antigens Class I/immunology , Histocompatibility Antigens Class II/immunology , Humans , Immunosuppressive Agents/administration & dosage , Influenza Vaccines/adverse effects , Influenza, Human/immunology , Influenza, Human/virology , Kidney Failure, Chronic/immunology , Kidney Failure, Chronic/surgery , Male , Middle Aged , Odds Ratio , Polysorbates/administration & dosage , Regression Analysis , Squalene/administration & dosage , Time Factors , Treatment Outcome , alpha-Tocopherol/administration & dosage
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