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Background and Aims: Little is known about genetic factors that affect development of alcohol-related cirrhosis. We performed a genome-wide association study (GWAS) of samples from the United Kingdom Biobank (UKB) to identify polymorphisms associated with risk of alcohol-related liver disease., Methods: We performed a GWAS of 35,839 participants in the UKB with high intake of alcohol against markers of hepatic fibrosis (FIB-4, APRI, and Forns index scores) and hepatocellular injury (levels of aminotransferases). Loci identified in the discovery analysis were tested for their association with alcohol-related cirrhosis in 3 separate European cohorts (phase 1 validation cohort; n=2545). Variants associated with alcohol-related cirrhosis in the validation at a false discovery rate of less than 20% were then directly genotyped in 2 additional European validation cohorts (phase 2 validation, n=2068)., Results: In the GWAS of the discovery cohort, we identified 50 independent risk loci with genome-wide significance (P < 5 × 10 -8 ). Nine of these loci were significantly associated with alcohol-related cirrhosis in the phase 1 validation cohort; 6 of these 9 loci were significantly associated with alcohol-related cirrhosis in phase 2 validation cohort, at a false discovery rate below 5%. The loci included variants in the mitochondrial amidoxime reducing component 1 gene (MARC1) and the heterogeneous nuclear ribonucleoprotein U like 1 gene (HNRNPUL1). After we adjusted for age, sex, body mass index, and type-2 diabetes in the phase 2 validation cohort, the minor A allele of MARC1:rs2642438 was associated with reduced risk of alcohol-related cirrhosis (adjusted odds ratio, 0.76; P=.0027); conversely, the minor C allele of HNRNPUL1:rs15052 was associated with an increased risk of alcohol-related cirrhosis (adjusted odds ratio, 1.30; P=.020)., Conclusions: In a GWAS of samples from the UKB, we identified and validated (in 5 European cohorts) single-nucleotide polymorphisms that affect risk of alcohol-related cirrhosis in opposite directions: the minor A allele in MARC1:rs2642438 decreases risk, whereas the minor C allele in HNRNPUL1:rs15052 increases risk., (Copyright © 2020 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background & Aims: Little is known about substitutions that mediate resistance of hepatitis C virus (HCV) to direct-acting antivirals (DAAs), due to the small number of patients with treatment failure in approval studies. It is important to identify resistance patterns to select effective salvage treatments., Methods: We performed a comprehensive analysis for resistance-associated substitutions (RASs) in HCV genes (nonstructural protein [NS]3, NS5A, NS5B) targeted by DAAs. We compared NS3, NS5A, and NS5B sequences from 626 patients in Europe with DAA failure with sequences from 2322 DAA-naïve patients, infected with HCV genotypes 1 to 4. We considered RASs to be relevant if they were associated with DAA failure in patients or conferred a greater than twofold change in susceptibility compared with a reference strain in in vitro replicon assays. Data were collected on pretreatment status, DAA regimen, the treatment initiation date and duration, and virologic response. Patients who received at least 4 weeks of antiviral treatment were included in the analysis., Results: RASs in NS3 associated with simeprevir or paritaprevir failure include R155K and D168E/V. In addition, several RASs were specifically associated with failure of simeprevir (Q80K/R in patients with genotype 1a or 4) or paritaprevir (Y56H in combination with D168V in patients with genotype 1b). Y93H in NS5A was the RAS most frequently associated with failure of daclatasvir, ledipasvir, or ombitasvir in patients with genotype 1b infection, and L31M was associated with failure of daclatasvir or ledipasvir, but not ombitasvir. RASs in NS5A were heterogeneous among patients with HCV genotype 1a or genotype 4 infections. In patients with HCV genotype 3, Y93H was associated with resistance to daclatasvir, but no RASs were associated with ledipasvir failure, pointing to a limited efficacy of ledipasvir in patients with genotype 3. Among patients failed by sofosbuvir-containing regimens, L159F was enriched in patients with genotype 1b (together with C316N) or genotype 3 infection, whereas the RAS S282T was rarely observed., Conclusions: We compared RASs in NS3, NS5A, and NS5B among patients failed by DAA therapy. Theses varied with the HCV genotype and subtype, and the different drug classes. These findings might be used to select salvage therapies., (Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background & Aims: Hepatitis C virus (HCV) acquires mutations that allow it to escape the CD8+ T-cell response, although the extent to which this process contributes to viral evolution at the population level is not clear. We studied viral adaptation using data from a large outbreak of HCV genotype 1b infection that occurred among women immunized with contaminated immunoglobulin from 1977 to 1978., Methods: The HCV nonstructural protein coding regions NS3-NS5B were sequenced from 78 patients, and mutations were mapped according to their location inside or outside previously described CD8+ T-cell epitopes. A statistical approach was developed to identify sites/regions under reproducible selection pressure associated with HLA class I., Results: The frequency of nonsynonymous mutations was significantly higher inside previously described CD8+ T-cell epitopes than outside-particularly in NS3/4A and NS5B. We identified new regions that are under selection pressure, indicating that not all CD8+ T-cell epitopes have been identified; 6 new epitopes that interact with CD8+ T cells were identified and confirmed in vitro. In some CD8+ T-cell epitopes mutations were reproducibly identified in patients that shared the relevant HLA allele, indicating immune pressure at the population level. There was statistical support for selection of mutations in 18 individual epitopes. Interestingly, 14 of these were restricted by HLA-B allele., Conclusions: HLA class I-associated selection pressure on the nonstructural proteins and here predominantly on NS3/4A and NS5B promotes evolution of HCV. HLA-B alleles have a dominant effect in this selection process. Adaptation of HCV to the CD8+ T-cell response at the population level creates challenges for vaccine design., (Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background & Aims: A single nucleotide polymorphism (SNP) upstream of the IL28B gene has been associated with response of patients with chronic hepatitis C to therapy with pegylated interferon and ribavirin and also with spontaneous clearance of acute hepatitis C in a heterogeneous population. We analyzed the association between IL28B and the clinical presentation of acute hepatitis C virus (HCV) infection in a homogeneous population., Methods: We analyzed the SNP rs12979860 in 190 women from the German anti-D cohort (infected with HCV genotype 1b via contaminated rhesus prophylaxis) and its association with spontaneous clearance. Clinical data were available in 136 women with acute infection who were also evaluated for IL28B genotype. Based on results of a TaqMan polymerase chain reaction assay, the rs12979860 SNP genotypes studied were C/C, C/T, or T/T., Results: Spontaneous clearance was more common in patients with the C/C genotype (43/67; 64%) compared with C/T (22/90; 24%) or T/T (2/33; 6%) (P < .001). Jaundice during acute infection was more common among patients with C/C genotype (32.7%) than non-C/C patients (with C/T or T/T) (16.1%; P = .032). In C/C patients, jaundice during acute infection was not associated with an increased chance of spontaneous clearance (56.3%) compared with those without jaundice (60.6%). In contrast, in non-C/C patients, jaundice was associated with a higher likelihood of spontaneous clearance (42.9%) compared with those without jaundice (13.7%)., Conclusions: The SNP rs12979860 upstream of IL28B is associated with spontaneous clearance of HCV. Women with the C/T or T/T genotype who did not develop jaundice had a lower chance of spontaneous clearance of HCV infection., (Copyright © 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background & Aims: Autoimmune hepatitis (AIH) is a chronic liver disease associated with cirrhosis and liver failure. Corticosteroid therapy induces long-term remission but has many side effects. We compared the effects of budesonide (a steroid that is rapidly metabolized, with low systemic exposure) and prednisone, both in combination with azathioprine., Methods: We performed a 6-month, prospective, double-blind, randomized, active-controlled, multicenter, phase IIb trial of patients with AIH without evidence of cirrhosis who were given budesonide (3 mg, three times daily or twice daily) or prednisone (40 mg/d, tapered to 10 mg/d); patients also received azathioprine (1-2 mg/kg/d). Treatment was followed by a 6-month, open-label phase during which all patients received budesonide in addition to azathioprine. The primary end point was complete biochemical remission, defined as normal serum levels of aspartate aminotransferase and alanine aminotransferase, without predefined steroid-specific side effects, at 6 months., Results: The primary end point was achieved in 47/100 patients given budesonide (47.0%) and in 19/103 patients given prednisone (18.4%) (P < .001; 97.5% 1-side confidence interval [CI] = 16.2). At 6 months, complete biochemical remission occurred in 60% of the patients given budesonide versus 38.8% of those given prednisone (P = .001; CI: 7.7); 72.0% of those in the budesonide group did not develop steroid-specific side effects versus 46.6% in the prednisone group (P < .001; CI = 12.3). Among 87 patients who were initially given prednisone and then received budesonide after 6 months, steroid-specific side effects decreased from 44.8% to 26.4% at month 12 (P < .002)., Conclusions: Oral budesonide, in combination with azathioprine, induces and maintains remission in patients with noncirrhotic AIH, with a low rate of steroid-specific side effects., (Copyright © 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.)

Background & Aims: The treatment of patients infected with hepatitis C virus (HCV) type 1 remains a challenge necessitating innovative strategies to improve treatment outcome. The extension of treatment duration beyond 48 weeks is one possible strategy to address this problem., Methods: The efficacy and safety of 48 weeks (group A, N = 230) vs 72 weeks (group B, N = 225) of treatment with pegylated-interferon-alfa-2a (180 microg/wk) plus ribavirin (800 mg/day) were studied in treatment-naive patients with HCV type 1 infection. On-treatment and sustained virologic response (SVR) 24 weeks after stopping treatment was assessed by qualitative reverse-transcription polymerase chain reaction (sensitivity 50 IU/mL)., Results: Overall, no significant differences could be observed in the treatment outcome between both groups. End-of-treatment and SVR rates in groups A and B were 71% vs 63% and 53% vs 54%, respectively. Patients with undetectable HCV-RNA levels already at weeks 4 and 12 had excellent SVR rates ranging from 76% to 84% regardless of treatment group, whereas patients shown to be still HCV-RNA positive at week 12 achieved significantly higher SVR rates when treated for 72 instead of 48 weeks (29% vs 17%, P = .040). A particular benefit from extended treatment duration was seen in patients with low-level viremia (<6000 IU/mL) at week 12. The frequency and intensity of adverse events was similar between the 2 groups., Conclusions: Extended treatment duration generally is not recommended in HCV type 1 infection and should be reserved only for patients with slow virologic response defined as HCV-RNA positive at week 12 but negative at week 24.

Background & Aims: A homozygous 32-base pair deletion in the CCR5 gene (CCR5-Delta32) protects against human immunodeficiency virus infection (HIV). However, the role of this mutation in other infections, such as hepatitis C virus (HCV) infection, has not been defined., Methods: We determined the frequency of the CCR5-Delta32 mutation by polymerase chain reaction in anti-HCV(+) (n = 153), anti-HIV(+) (n = 102), and anti-HCV(+)/HIV(+) (n = 130) white patients as well as in 102 healthy blood donors. Then, HIV and HCV loads, aminotransferases, and CD4 and CD8 cell counts were compared between the resulting subsets of CCR5-Delta32/wild-type heterozygotes, CCR5-Delta32, and wild-type homozygotes, respectively., Results: Twelve of 153 (7.8%) anti-HCV-seropositive patients and 1 of 102 (1.0%) healthy blood donors were CCR5-Delta32 homozygous, whereas CCR5-Delta32 homozygosity was absent in anti-HIV(+) and anti-HCV(+)/HIV(+) patients (P < 0.001). The frequency of the CCR5-Delta32 allele was higher in the anti-HCV(+) (16.0%, P < 0.05) and anti-HCV(+)/HIV(+) (12.7%, NS) patients than in healthy blood donors (8.3%) and anti-HIV(+) patients (9.3%), respectively. Anti-HCV(+) CCR5-Delta32 homozygotes occurred 3 times more frequently than expected from the Hardy-Weinberg equation (P < 0.0001) and had significantly higher HCV loads than wild-type patients (P = 0.045)., Conclusions: The increased prevalence of CCR5-Delta32 homozygosity associated with increased viral loads in patients with chronic hepatitis C suggests that the CCR5-Delta32 mutation may be an adverse host factor in hepatitis C.

Background & Aims: The tumor necrosis factor (TNF)-alpha/TNF receptor system is critical for liver development because hepatocytes undergo apoptosis if the antiapoptotic cascades resulting in RelA NF-kappaB activation are not effective. Therefore, we studied the role of TNF-alpha in fulminant hepatic failure (FHF) and developed a new therapeutic strategy., Methods: Serum levels and hepatic expression of TNF-alpha and both TNF receptors were determined by enzyme-linked immunosorbent assay and immunohistochemistry. Adenoviral vectors were constructed expressing dominant-negative proteins interfering with intracellular TNF-alpha-dependent pathways. The relevance of these constructs was studied in primary mouse hepatocytes and in a murine model of FHF., Results: Serum levels of TNF-alpha and TNF receptors are significantly increased in FHF; this increase correlates with patient prognosis. In livers of patients with FHF, infiltrating mononuclear cells express high amounts of TNF-alpha and hepatocytes overexpress TNF receptor 1 (TNF-R1). Apoptotic hepatocytes are significantly increased in FHF, and there is a strong correlation with TNF-alpha expression, which is even more pronounced in areas of mononuclear infiltrates. In an in vivo FHF model, the Fas-associated death domain (FADD), adenovirus selectively blocked the intracellular pathway, leading to mitochondrial cytochrome c release, caspase-3 activation, and, thus, apoptosis of hepatocytes., Conclusions: The results show that the TNF-alpha/TNF-R1 system is involved in the pathogenesis of FHF in humans. Studies in this animal model indicate that FADD may serve as a molecular target to prevent liver cell death in vivo.

Background & Aims: Atypical "antineutrophil cytoplasmic antibodies" (ANCA) are present in patients with ulcerative colitis (UC), primary sclerosing cholangitis (PSC), and autoimmune hepatitis (AIH). Recently, we showed that atypical p-ANCA react with nuclear envelope proteins of neutrophils. Based on this observation, we aimed to characterize the nuclear antigen recognized by atypical p-ANCA., Methods: We prepared cytoplasmic and nuclear extracts of human neutrophils, human HL-60, and murine 32D myeloid cells. Proteins were resolved by 1- and 2-dimensional gel electrophoresis. Reactive proteins were detected by immunoblotting with sera from 118 individuals (UC, 25; PSC, 28; AIH, 35; disease and normal controls, 30). Atypical p-ANCA (n = 64) were affinity-purified against the reactive protein and investigated for their immunofluorescence pattern using confocal microscopy., Results: Immunoblotting showed reactivity to a myeloid-specific 50-kilodalton nuclear protein with an isoelectric point of pH 6.0 detected in 92% (59 of 64) of the patients with inflammatory bowel or hepatobiliary diseases and atypical p-ANCA. Affinity-purified antibodies against the 50-kilodalton protein gave a nuclear rim-like fluorescence on myeloid cells examined by immunofluorescence microscopy. Affinity-purified antibodies did not recognize antigens in nonmyeloid cells., Conclusions: Atypical p-ANCA in UC, PSC, or AIH recognize a 50-kilodalton myeloid-specific nuclear envelope protein.

Background & Aims: Patients with cirrhosis are characterized by a reduced splanchnic vascular resistance and a hyporeactivity to adrenergic vasoconstrictors. So far, their adrenergic splanchnic vascular responsiveness has not been evaluated in vitro. We compared responses to alpha1- and beta2-adrenoceptor stimulation of hepatic arteries and portal veins of patients with cirrhosis undergoing transplantation with those of organ donors., Methods: Isometric contractions of endothelium-denuded vessel rings were induced cumulatively by methoxamine and relaxations by isoproterenol. Results are expressed as percentage of the contraction obtained by 85 mmol/L KCl or of the relaxation obtained by 100 micromol/L papaverine, respectively., Results: Maximal methoxamine-induced contractions were reduced in cirrhotic hepatic arteries (cirrhosis, 51.8% +/- 6.8%; donor, 89.9% +/- 6.6%; P < 0.01) and portal veins (cirrhosis, 49.2% +/- 6.4%; donor, 94.0% +/- 5.3%; P < 0.01). In cirrhosis, isoproterenol induced a less marked relaxation of hepatic arteries (cirrhosis, 46.6% +/- 3.2%; donor, 100.3% +/- 4.4%; P < 0. 01) but an increased relaxation of portal veins (cirrhosis, 41.9% +/- 6.2%; donor, 26.2% +/- 2.8%; P < 0.01)., Conclusions: In cirrhosis, endothelium-free hepatic arteries are hyporeactive to alpha1- and beta2-adrenoceptor agonists, and portal veins are hyporeactive to alpha1- but hyperreactive to beta2-adrenoceptor agonists. These findings support the in vivo findings of a hyporesponsiveness to adrenergic vasoconstrictors in patients with cirrhosis.