Citations

Background: Alcohol-associated hepatitis (AH) is a severe inflammatory liver condition driven by dysregulated immune responses. CD8 T cells accumulate in the liver during AH, yet their functional role remains poorly defined. Methods: A murine NIAAA chronic-binge model with lipopolysaccharide (LPS) challenge was used. Single-cell RNA sequencing of liver and blood immune cells defined CD8 T cell subsets, followed by pathway analysis and reanalysis of human AH datasets. Spatial relationships were validated by immunohistochemistry of human AH liver tissue with CD8 T RM and liver sinusoidal endothelial cell (LSEC) co-staining. LSEC–CD8 T cell interactions were examined using in vitro co-culture, and signaling pathways were assessed by bulk RNA sequencing and phospho-protein analyses. IL15 function was evaluated by in vivo neutralization. Results: Single-cell RNA sequencing in the murine AH model revealed a distinct population of CD8 tissue-resident memory T cells (T RM ) with heightened activation and proinflammatory cytokine production. Analysis of human AH liver single-cell RNA sequencing data, along with immunohistochemistry validation, supported CD8 T RM enrichment in diseased tissue. IL15 emerged as a prominent pathway linked to T RM activation, and IL15 blockade reduced T RM abundance and attenuated EtOH/ lipopolysaccharide-induced liver injury. Mechanistically, LSECs not only provided a structural niche for T RM retention but also amplified IL15 signalling. In vitro, coculture experiments demonstrated that LSECs intensified activation in pre-stimulated CD8 T cells in a stimulus-dependent manner: under IL15 stimulation, LSECs boosted effector function without inducing cell death, whereas under T-cell receptor stimulation, LSECs drove hyperactivation and activation-induced cell death. Bulk RNA-seq and phospho-protein analysis identified the PI3K-AKT pathway as a shared pathway enhanced by LSEC coculture in activated CD8 T cells. These findings define a context-dependent mechanism in which LSECs promote IL15-driven signaling through AKT pathway amplification, promoting T RM persistence and inflammatory activity in AH. Conclusions: IL15-associated signaling within the hepatic microenvironment, shaped by LSEC-CD8 T-cell interactions, promotes activation and persistence of CD8 T RM cells in AH. Targeting the IL15-LSEC-AKT axis may disrupt pathogenic T RM niches and represent a promising therapeutic strategy for severe AH.

Background: How parental alcohol use disorder and liver disease-related mortality influence the risk and the outcomes of alcohol-associated hepatitis (AH) in the offspring is unknown. Methods: We analyzed data from 2 prospective observational studies of AH cases and heavy drinking controls (HDCs). Family history of parental alcohol use disorder and liver disease mortality was assessed at the study entry. Logistic regression and Cox proportional hazard models were used to assess the influences of family history on AH development and outcome. Results: Data from 1356 participants in two prospective cohorts (926 AH cases and 430 HDC) were combined and analyzed. Parental alcohol use disorder was found in 56.9% of AH cases and 61.1% of HDC; parental death due to liver disease was reported in 7.5% of AH cases and 5.7% of HDC. Multivariable logistic regression showed that parental liver disease-related mortality was associated with more than a doubled risk of AH development in the offspring after controlling for their demographic characteristics and drinking behavior (OR=2.26, 95% CI: [1.22, 4.20]). Moreover, among the AH cases, having a parent die of liver disease significantly increased the 90-day mortality of study participants after adjusting for the effects of other risk factors (HR=2.26, 95% CI: [1.05, 4.86]). Conclusions: The study highlights the influences of parental death due to liver disease on AH development and mortality. Identifying patients at risk of AH through family history might help facilitate discussions on reducing alcohol consumption.

AbstractBackground and AimIn recent years, there has been a growing incidence of gastrointestinal cancer in young individuals. Despite its significant morbidity and mortality, research on upper gastrointestinal (UGI) cancer in young populations has been relatively limited. Therefore, studies on the epidemiological changes of this cancer are needed.MethodsUsing data from the Global Burden of Disease Study 2019, we examined the incidence, death, and disability‐adjusted life years (DALYs) from UGI cancers in the young, namely, early‐onset esophageal cancer (EOEC) and early‐onset gastric cancer (EOGC). These results were stratified by sex, geographical region, country, and sociodemographic index.ResultsThere was a total of 185 140 cases, 120 289 deaths, and 5.70 million DALYs attributable to early‐onset UGI cancers globally. From 2010 to 2019, the global incidence, death, and DALYs rates of early‐onset UGI cancers decreased. In contrast, the incidence rates increased in both EOEC (+1.15%) and EOGC (+0.21%) in the Eastern Mediterranean region.ConclusionsOver the past decade, the burden of UGI cancer in the young has decreased. However, it has increased in the Eastern Mediterranean region. Further research to elucidate the attributable risk factors in this population is warranted.

Emerging evidence suggest that transcription factors play multiple roles in the development of pancreatitis, a necroinflammatory condition lacking specific therapy. Estrogen-related receptor γ (ERRγ), a pleiotropic transcription factor, has been reported to play a vital role in pancreatic acinar cell (PAC) homeostasis. However, the role of ERRγ in PAC dysfunction remains hitherto unknown. Here, we demonstrated in both mice models and human cohorts that pancreatitis is associated with an increase in ERRγ gene expression via activation of STAT3. Acinar-specific ERRγ haploinsufficiency or pharmacological inhibition of ERRγ significantly impaired the progression of pancreatitis both in vitro and in vivo. Using systematic transcriptomic analysis, we identified that voltage-dependent anion channel 1 (VDAC1) acts as a molecular mediator of ERRγ. Mechanistically, we showed that induction of ERRγ in cultured acinar cells and mouse pancreata enhanced VDAC1 expression by directly binding to specific site of the Vdac1 gene promoter and resulted in VDAC1 oligomerization. Notably, VDAC1, whose expression and oligomerization were dependent on ERRγ, modulates mitochondrial Ca 2+ and ROS levels. Inhibition of the ERRγ–VDAC1 axis could alleviate mitochondrial Ca 2+ accumulation, ROS formation and inhibit progression of pancreatitis. Using two different mouse models of pancreatitis, we showed that pharmacological blockade of ERRγ–VDAC1 pathway has therapeutic benefits in mitigating progression of pancreatitis. Likewise, using PRSS1 R122H -Tg mice to mimic human hereditary pancreatitis, we demonstrated that ERRγ inhibitor also alleviated pancreatitis. Our findings highlight the importance of ERRγ in pancreatitis progression and suggests its therapeutic intervention for prevention and treatment of pancreatitis.

Abstract Alcoholic hepatitis (AH) develops in a small percentage of heavy drinkers. The adaptive immune system of AH patients is hyper-activated, yet dysregulated and ineffective against infectious diseases. Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes that are found in liver, intestinal mucosa, and peripheral blood and contribute to protection against infectious diseases. To determine whether MAIT cells were dysregulated in heavy drinkers and the effect of alcohol abstinence on MAIT cell recovery, we compared peripheral MAIT cells between AH patients and heavy drinkers without liver disease (HDC) at baseline and 6- and 12-month followup. At baseline, AH patients had severely reduced frequency of MAIT cells than HDC and healthy donor controls (HC), whereas MAIT cell frequency was not significantly different between HDC and HC. In addition, MAIT cells in AH patients expressed higher levels of the activation markers (CD69, CD38, and HLA-DR) as well as the immune checkpoint inhibitor PD-1. Multiplex immunoassays showed that plasma levels of several cytokines related to MAIT cell activation were elevated in AH patients (IFN-s, IL-7, IL-15, IL-17, IL-18, and IL-23, and TNF-a). In AH patients, the frequency MAIT cells and CD38-expressing MAIT cells correlated with levels of several cytokines and AST. At followup, AH patients had increased MAIT cell frequency and decreased MAIT cell activation with cessation of alcohol. However, abstinent AH patients still had higher levels of CD38-expressing MAIT cells than HDC at 6-month followup. Conclusion Blood MAIT cells were severely reduced and were dysregulated in AH patients and alcohol abstinence partially reversed abnormalities in MAIT cell frequency and phenotype.

Abstract Alcohol‐associated liver disease (ALD) is emerging worldwide as the leading cause of liver‐related morbidity, mortality, and indication for liver transplantation. The ALD Special Interest Group and the Clinical Research Committee at the digital American Association for the Study of Liver Diseases meeting in November 2020 held the scientific sessions to identify clinical unmet needs in ALD, and addressing these needs using clinical research methodologies. Of several research methodologies, the sessions were focused on (a) studying disease burden of ALD using large administrative databases, (b) developing biomarkers for noninvasive diagnosis of alcohol‐associated hepatitis (AH) and estimation of disease prognosis, (c) identifying therapeutic targets for ALD and AH, (d) deriving accurate models to predict prognosis or posttransplant alcohol relapse as a basis for developing treatment algorithm and a uniform protocol on patient‐selection criteria for liver transplantation, and (e) examining qualitative research methodologies in studying the barriers to implementation of multidisciplinary integrated care model by hepatology and addiction teams for the management of dual pathology of liver disease and of alcohol use disorder. Prospective multicenter studies are required to address many of these clinical unmet needs. Further, multidisciplinary care models are needed to improve long‐term outcomes in patients with ALD.

Background and Aims We conducted a comprehensive serum transcriptomic analysis to explore the roles of microRNAs (miRNAs) in alcohol‐associated hepatitis (AH) pathogenesis and their prognostic significance. Approach and Results Serum miRNA profiling was performed in 15 controls, 20 heavy drinkers without liver disease, and 65 patients with AH and compared to publicly available hepatic miRNA profiling in AH patients. Among the top 26 miRNAs, expression of miR‐30b‐5p, miR‐20a‐5p, miR‐146a‐5p, and miR‐26b‐5p were significantly reduced in both serum and liver of AH patients. Pathway analysis of the potential targets of these miRNAs uncovered the genes related to DNA synthesis and cell‐cycle progression pathways, including ribonucleotide reductase regulatory subunit M2 (RRM2), cyclin D1 (CCND1), cyclin D2 (CCND2), MYC proto‐oncogene (MYC), and phorbol‐12‐myristate‐13‐acetate‐induced protein 1 (PMAIP1). We found a significant increase in the protein expression of RRM2, CCND1, and CCND2, but not MYC and PMAIP1, in AH patients who underwent liver transplantation; miR‐26b‐5p and miR‐30b‐5p inhibited the 3′‐UTR (untranslated region) luciferase activity of RRM2 and CCND2, and miR‐20a‐5p reduced the 3′‐UTR luciferase activity of CCND1 and CCND2. During a median follow‐up of 346 days, 21% of AH patients died; these patients had higher body mass index (BMI), Model for End‐Stage Liver Disease (MELD), and serum miR‐30b‐5p, miR‐20a‐5p, miR‐146a‐5p, and miR‐26b‐5p than those who survived. Cox regression analysis showed that BMI, MELD score, miR‐20a‐5p, miR‐146a‐5p, and miR‐26b‐5p predicted mortality. Conclusions Patients with AH attempt to deal with hepatocyte injury by down‐regulating specific miRNAs and up‐regulating genes responsible for DNA synthesis and cell‐cycle progression. Higher expression of these miRNAs, suggestive of a diminished capacity in liver regeneration, predicts short‐term mortality in AH patients.

Background and Aims The role of the intestinal microbiome in alcoholic hepatitis is not established. The aims of this study were to (1) characterize the fecal microbial ecology associated with alcoholic hepatitis, (2) relate microbiome changes to disease severity, and (3) infer the functional relevance of shifts in microbial ecology. Approach and Results The fecal microbiome in patients with moderate alcoholic hepatitis (MAH) or severe alcoholic hepatitis (SAH) was compared with healthy controls (HCs) and heavy drinking controls (HDCs). Microbial taxa were identified by 16S pyrosequencing. Functional metagenomics was performed using PICRUSt. Fecal short chain fatty acids (SCFAs) were measured using a liquid chromatography–mass spectrometry platform. A total of 78 participants (HC, n = 24; HDC, n = 20; MAH, n = 10; SAH, n = 24) were studied. HDC had a distinct signature compared with HC with depletion of Bacteroidetes (46% vs. 26%; P = 0.01). Alcoholic hepatitis was associated with a distinct microbiome signature compared with HDC (area under the curve = 0.826); differential abundance of Ruminococcaceae , Veillonellaceae , Lachnospiraceae , Porphyromonadaceae , and Rikenellaceae families were the key contributors to these differences. The beta diversity was significantly different among the groups (permutational multivariate analysis of variance [PERMANOVA] P < 0.001). SAH was associated with increased Proteobacteria (SAH 14% vs. HDC 7% and SAH vs. HC 2%, P = 0.20 and 0.01, respectively). Firmicutes abundance declined from HDC to MAH to SAH (63% vs. 53% vs. 48%, respectively; P = 0.09, HDC vs. SAH). Microbial taxa did not distinguish between MAH and SAH (PERMANOVA P = 0.785). SCFAs producing bacteria (Lachnospiraceae and Ruminococcaceae) were decreased in alcoholic hepatitis, and a similar decrease was observed in fecal SCFAs among alcoholic hepatitis patients. Conclusions There are distinct changes in fecal microbiome associated with the development, but not severity, of alcoholic hepatitis.

OBJECTIVES: Alcoholic hepatitis (AH) develops in approximately 30% of chronic heavy drinkers. The immune system of patients with AH is hyperactivated, yet ineffective against infectious diseases. Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes that are highly enriched in liver, mucosa, and peripheral blood and contribute to antimicrobial immunity. We aimed to determine whether MAIT cells were dysregulated in heavy drinkers with and without AH and the effects of alcohol abstinence on MAIT cell recovery. METHODS: MR1 tetramers loaded with a potent MAIT cell ligand 5-(2-oxopropylideneamino)-6-d-ribitylaminouracil were used in multiparameter flow cytometry to analyze peripheral blood MAIT cells in 59 healthy controls (HC), 56 patients with AH, and 45 heavy drinkers without overt liver disease (HDC) at baseline and 6- and 12-month follow-ups. Multiplex immunoassays were used to quantify plasma levels of cytokines related to MAIT cell activation. Kinetic Turbidimetric Limulus Amebocyte Lysate Assay and ELISA were performed to measure circulating levels of 2 surrogate markers for bacterial translocation (lipopolysaccharide and CD14), respectively. RESULTS: At baseline, patients with AH had a significantly lower frequency of MAIT cells than HDC and HC. HDC also had less MAIT cells than HC (median 0.16% in AH, 0.56% in HDC, and 1.25% in HC). Further, the residual MAIT cells in patients with AH expressed higher levels of activation markers (CD69, CD38, and human leukocyte antigen [HLA]-DR), the effector molecule granzyme B, and the immune exhaustion molecule PD-1. Plasma levels of lipopolysaccharide and CD14 and several cytokines related to MAIT cell activation were elevated in patients with AH (interferon [IFN]-α, interleukin [IL]-7, IL-15, IL-17, IL-18, IL-23, IFN-γ, and tumor necrosis factor α). Decreased MAIT cell frequency and upregulated CD38, CD69, and HLA-DR correlated negatively and positively, respectively, with aspartate aminotransferase level. MAIT cell frequency negatively correlated with IL-18. HLA-DR and CD38 levels correlated with several cytokines. At follow-ups, abstinent patients with AH had increased MAIT cell frequency and decreased MAIT cell activation. However, MAIT cell frequency was not fully normalized in patients with AH (median 0.31%). DISCUSSION: We showed that HDC had a reduction of blood MAIT cells despite showing little evidence of immune activation, whereas patients with AH had a severe depletion of blood MAIT cells and the residual cells were highly activated. Alcohol abstinence partially reversed those abnormalities.