Mass Cytometry of the Human Mucosal Immune System Identifies Tissue- and Disease-Associated Immune Subsets.

Inflammatory intestinal diseases are characterized by abnormal immune responses and affect distinct locations of the gastrointestinal tract. Although the role of several immune subsets in driving intestinal pathology has been studied, a system-wide approach that simultaneously interrogates all major lineages on a single-cell basis is lacking. We used high-dimensional mass cytometry to generate a system-wide view of the human mucosal immune system in health and disease. We distinguished 142 immune subsets and through computational applications found distinct immune subsets in peripheral blood mononuclear cells and intestinal biopsies that distinguished patients from controls. In addition, mucosal lymphoid malignancies were readily detected as well as precursors from which these likely derived. These findings indicate that an integrated high-dimensional analysis of the entire immune system can identify immune subsets associated with the pathogenesis of complex intestinal disorders. This might have implications for diagnostic procedures, immune-monitoring, and treatment of intestinal diseases and mucosal malignancies.

Histological characteristics in patients admitted to the hospital with alcoholic hepatitis complicated by acute-on-chronic liver failure.

OBJECTIVES: Alcoholic hepatitis (AH) is a frequent precipitating event for the development of acute-on-chronic liver failure (ACLF), a syndrome characterised by organ failures due to immune dysfunction. The histological features of this complication are not well characterized. We investigated whether ACLF has specific histological characteristics. METHODS: Prospective cohort study in consecutive adult patients admitted between 03-2008 and 04-2021 to a tertiary referral centre with suspected AH. Diagnosis of AH was based on clinical presentation and confirmed by transjugular liver biopsy. All biopsies were assessed by a dedicated liver pathologist, blinded for clinical data and outcome. Diagnosis of ACLF was based on EASL-CLIF criteria. Histological and clinical characteristics of patients with and without ACLF at baseline were compared. RESULTS: 184 patients with biopsy-proven AH were enrolled. Median time from hospital admission to transjugular biopsy was 4.5 days (IQR 2-8). At baseline, ACLF was present in 73 patients (39.7%). Out of the 110 patients without ACLF at baseline, 30 (27.3%) developed ACLF within 28 days (median 7.5 days (IQR 2-20)). At baseline, ductular bilirubinostasis (DB) was the only histological feature significantly more frequently present in patients with ACLF compared to patients without ACLF (50.7% vs. 30.6%, p = 0.003). No clear association between histological features and the development of ACLF later on could be demonstrated. CONCLUSIONS: In this well-defined cohort of patients with biopsy-proven AH, DB was associated with the presence of ACLF. This finding fits with the pathophysiology of this syndrome, which is characterized by systemic inflammation and an increased risk of infections.

Fecal Microbiota Transplantation Influences Procarcinogenic Escherichia coli in Recipient Recurrent Clostridioides difficile Patients.

BACKGROUND & AIMS: Patients with multiple recurrent Clostridioides difficile infection (rCDI) have a disturbed gut microbiota that can be restored by fecal microbiota transplantation (FMT). Despite extensive screening, healthy feces donors may carry bacteria in their intestinal tract that could have long-term health effects, such as potentially procarcinogenic polyketide synthase-positive (pks+) Escherichia coli. Here, we aim to determine whether the pks abundance and persistence of pks+E coli is influenced by pks status of the donor feces. METHODS: In a cohort of 49 patients with rCDI treated with FMT and matching donor samples-the largest cohort of its kind, to our knowledge-we retrospectively screened fecal metagenomes for pks+E coli and compared the presence of pks in patients before and after treatment and to their respective donors. RESULTS: The pks island was more prevalent (P = .026) and abundant (P < .001) in patients with rCDI (pre-FMT, 27 of 49 [55%]; median, 0.46 reads per kilobase per million [RPKM] pks) than in healthy donors (3 of 8 donors [37.5%], 11 of 38 samples [29%]; median, 0.01 RPKM pks). The pks status of patients post-FMT depended on the pks status of the donor suspension with which the patient was treated (P = .046). Particularly, persistence (8 of 9 cases) or clearance (13 of 18) of pks+E coli in pks+ patients was correlated to pks in the donor (P = .004). CONCLUSIONS: We conclude that FMT contributes to pks+E coli persistence or eradication in patients with rCDI but that donor-to-patient transmission of pks+E coli is unlikely.

Genetic variants of innate immunity receptors are associated with mortality in cirrhotic patients with bacterial infection.

BACKGROUND & AIMS: Acute-on-chronic liver failure (ACLF) is characterized by acute decompensation of cirrhosis (AD), organ failure(s) and high risk of short-term mortality with bacterial infection frequently as precipitating event. Innate immune pattern recognition receptors and members of the lectin pathway of complement activation are crucial to the innate immune response to pathogens. The aim of this study was to investigate whether single nucleotide polymorphisms (SNPs) of innate immune components are associated with the occurrence of bacterial infections or mortality in patients with cirrhosis hospitalized for AD or ACLF. METHODS: Twenty-one innate immunity SNPs with known functional implications were genotyped in 826 AD/ACLF patients included in the CANONIC study. Associations between baseline characteristics of the patients, the occurrence of bacterial infections and survival rate at 90 days of follow-up in relation to the innate immunity genetic variants were analysed. RESULTS: The NOD2-G908R genetic variant was associated with mortality (HR 2.25, P = .004) independently of age and MELD Score. This association was also found in a predefined subgroup analysis in patients with bacterial infections (HR 2.78, P < .001) along with MBL_Yx (HR 1.72, P = .008) and MASP2_371 (HR 1.67, P = .012) genetic variants. None of the analysed SNPs were significantly associated with the occurrence of acute bacterial infections or spontaneous bacterial peritonitis in particular. CONCLUSIONS: Innate immune system-specific NOD2-G908R, MBL_Yx and MASP2_371 genetic variants were independently associated with increased risk of short-term mortality in AD/ACLF patients with bacterial infection.

Local but not systemic administration of mesenchymal stromal cells ameliorates fibrogenesis in regenerating livers.

Chronic liver injury leads to the accumulation of myofibroblasts resulting in increased collagen deposition and hepatic fibrogenesis. Treatments specifically targeting fibrogenesis are not yet available. Mesenchymal stromal cells (MSCs) are fibroblast-like stromal (stem) cells, which stimulate tissue regeneration and modulate immune responses. In the present study we assessed whether liver fibrosis and cirrhosis can be reversed by treatment with MSCs or fibroblasts concomitant to partial hepatectomy (pHx)-induced liver regeneration. After carbon tetrachloride-induced fibrosis and cirrhosis, mice underwent a pHx and received either systemically or locally MSCs in one of the two remaining fibrotic/cirrhotic liver lobes. Eight days after treatment, liver fibrogenesis was evaluated by Sirius-red staining for collagen deposition. A significant reduction of collagen content in the locally treated lobes of the regenerated fibrotic and cirrhotic livers was observed in mice that received high dose MSCs. In the non-MSC-treated counterpart liver lobes no changes in collagen deposition were observed. Local fibroblast administration or intravenous administration of MSCs did not ameliorate fibrosis. To conclude, local administration of MSCs after pHx, in contrast to fibroblasts, results in a dose-dependent on-site reduction of collagen deposition in mouse models for liver fibrosis and cirrhosis.

CRIPTO promotes an aggressive tumour phenotype and resistance to treatment in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. Despite increasing treatment options for this disease, prognosis remains poor. CRIPTO (TDGF1) protein is expressed at high levels in several human tumours and promotes oncogenic phenotype. Its expression has been correlated to poor prognosis in HCC. In this study, we aimed to elucidate the basis for the effects of CRIPTO in HCC. We investigated CRIPTO expression levels in three cohorts of clinical cirrhotic and HCC specimens. We addressed the role of CRIPTO in hepatic tumourigenesis using Cre-loxP-controlled lentiviral vectors expressing CRIPTO in cell line-derived xenografts. Responses to standard treatments (sorafenib, doxorubicin) were assessed directly on xenograft-derived ex vivo tumour slices. CRIPTO-overexpressing patient-derived xenografts were established and used for ex vivo drug response assays. The effects of sorafenib and doxorubicin treatment in combination with a CRIPTO pathway inhibitor were tested in ex vivo cultures of xenograft models and 3D cultures. CRIPTO protein was found highly expressed in human cirrhosis and hepatocellular carcinoma specimens but not in those of healthy participants. Stable overexpression of CRIPTO in human HepG2 cells caused epithelial-to-mesenchymal transition, increased expression of cancer stem cell markers, and enhanced cell proliferation and migration. HepG2-CRIPTO cells formed tumours when injected into immune-compromised mice, whereas HepG2 cells lacking stable CRIPTO overexpression did not. High-level CRIPTO expression in xenograft models was associated with resistance to sorafenib, which could be modulated using a CRIPTO pathway inhibitor in ex vivo tumour slices. Our data suggest that a subgroup of CRIPTO-expressing HCC patients may benefit from a combinatorial treatment scheme and that sorafenib resistance may be circumvented by inhibition of the CRIPTO pathway. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Donor-specific anti-HLA antibodies are not associated with nonanastomotic biliary strictures but both are independent risk factors for graft loss after liver transplantation.

Donor-specific alloantibodies (DSA) have been associated with rejection and shorter graft survival after orthotopic liver transplantation (OLT). We examined the role of DSA in nonanastomotic biliary strictures (NAS) after OLT. Patients receiving first OLT who developed NAS (n = 68) and a control group without NAS (n = 83), with pre-OLT and 12 months post-OLT serum samples, were included. DSA were specified using the Luminex single antigen test. Risk factors for NAS and graft survival were analyzed. The presence of preformed DSA was not significantly different between patients with NAS and controls (P = .89). After 12 months, 26.5% of NAS patients and 16.9% of controls had generated de novo DSA (P = .15). Neither de novo class I DSA nor de novo class II DSA were associated with NAS. De novo DSA generally developed after the diagnosis of NAS. Time-dependent regression analysis identified both NAS (aHR 8.05, CI 3.28 - 19.77, P < .01) and de novo class II DSA (aHR 2.84, CI 1.38 - 5.82, P < .01) as independent risk factors for graft loss. Preformed or de novo DSA were not associated with the development of NAS. However, NAS as well as de novo class II DSA were independent risk factors for graft loss after OLT.

Impact of hepatic encephalopathy on liver transplant waiting list mortality in regions with different transplantation rates.

Overt hepatic encephalopathy (OHE) negatively impacts the prognosis of liver transplant candidates. However, it is not taken into account in most prioritizing organ allocation systems. We aimed to assess the impact of OHE on waitlist mortality in 3 cohorts of cirrhotic patients awaiting liver transplantation, with differences in the composition of patient population, transplantation policy, and transplantation rates. These cohorts were derived from two centers in the Netherlands (reference and validation cohort, n = 246 and n = 205, respectively) and one in Spain (validation cohort, n = 253). Competing-risk regression analysis was applied to assess the association of OHE with 1-year waitlist mortality. OHE was found to be associated with mortality, independently of MELD score, other cirrhosis-related complications and hepatocellular carcinoma (HCC; sHR = 4.19, 95% CI = 1.9-9.5, P = 0.001). The addition of extra MELD points for OHE counteracted its negative impact on survival. These findings were confirmed in the Dutch validation cohort, whereas in the Spanish cohort, containing a significantly greater proportion of HCC and with higher transplantation rates, OHE was not associated with mortality. In conclusion, OHE is an independent risk factor for 1-year waitlist mortality and might be a prioritization rule for organ allocation. However, its impact seems to be attenuated in settings with significantly higher transplantation rates.

Copeptin in acute decompensation of liver cirrhosis: relationship with acute-on-chronic liver failure and short-term survival.

BACKGROUND: Acute-on-chronic liver failure (ACLF) is characterized by the presence of acute decompensation (AD) of cirrhosis, organ failure, and high short-term mortality rates. Hemodynamic dysfunction and activation of endogenous vasoconstrictor systems are thought to contribute to the pathogenesis of ACLF. We explored whether copeptin, a surrogate marker of arginine vasopressin, is a potential marker of outcome in patients admitted for AD or ACLF and whether it might be of additional value to conventional prognostic scoring systems in these patients. METHODS: All 779 patients hospitalized for AD of cirrhosis from the CANONIC database with at least one serum sample available for copeptin measurement were included. Presence of ACLF was defined according to the CLIF-consortium organ failure (CLIF-C OF) score. Serum copeptin was measured in samples collected at days 0-2, 3-7, 8-14, 15-21, and 22-28 when available. Competing-risk regression analysis was applied to evaluate the impact of serum copeptin and laboratory and clinical data on short-term survival. RESULTS: Serum copeptin concentration was found to be significantly higher in patients with ACLF compared with those without ACLF at days 0-2 (33 (14-64) vs. 11 (4-26) pmol/L; p < 0.001). Serum copeptin at admission was shown to be a predictor of mortality independently of MELD and CLIF-C OF scores. Moreover, baseline serum copeptin was found to be predictive of ACLF development within 28 days of follow-up. CONCLUSIONS: ACLF is associated with significantly higher serum copeptin concentrations at hospital admission compared with those with traditional AD. Copeptin is independently associated with short-term survival and ACLF development in patients admitted for AD or ACLF.

Plasma copeptin as biomarker of disease progression and prognosis in cirrhosis.

BACKGROUND & AIMS: Research on vasopressin (AVP) in cirrhosis and its role in the assessment of prognosis has been hindered by the difficulty of measuring AVP levels accurately. Copeptin, a 39-aminoacid glycopeptide, is released from the neurohypophysis together with AVP. Copeptin could have a role as biomarker of prognosis in cirrhosis as it may reflect circulatory dysfunction. The aim of this study is to investigate the role of copeptin as biomarker of disease progression and prognosis in cirrhosis. METHODS: This prospective study is divided in 2 study protocols including 321 consecutive patients. Plasma copeptin levels were measured in all patients at study inclusion. Protocol 1: to investigate the relationship of copeptin with kidney and circulatory function (56 patients). Protocol 2: to investigate the relationship between copeptin and prognosis, as assessed by the development of complications of cirrhosis or mortality at 3months (265 patients admitted to hospital for complications of cirrhosis). RESULTS: Patients with decompensated cirrhosis showed significantly higher plasma copeptin levels compared to those of patients with compensated cirrhosis. Copeptin levels had a significant positive correlation with model for end-satge liver disease (MELD) score, AVP, endogenous vasoconstrictor systems, and kidney function parameters. Patients developing complications of cirrhosis or mortality had significantly higher plasma copeptin levels compared to those of the remaining patients. Plasma copeptin levels were an independent predictive factor of both the development of complications and mortality at 3months. This was confirmed in a validation series of 120 patients. CONCLUSIONS: Copeptin is a novel biomarker of disease progression and prognosis in cirrhosis. LAY SUMMARY: Copeptin is a fragment of the vasopressin precursor, a hormone that is known to be increased in patients with cirrhosis and that plays a role in the development of complications of the disease. Vasopressin is difficult to measure, but copeptin is a more stable molecule and is easier to measure in blood. Solà and Kerbert and colleagues have shown in a series of 361 patients that copeptin is markedly increased in patients with cirrhosis who develop complications during the following 3months, compared to those patients who do not develop complications. Moreover, copeptin correlates with prognosis.

MicroRNA214 Is Associated With Progression of Ulcerative Colitis, and Inhibition Reduces Development of Colitis and Colitis-Associated Cancer in Mice.

BACKGROUND & AIMS: Persistent activation of the inflammatory response contributes to the development of inflammatory bowel diseases, which increase the risk of colorectal cancer. We aimed to identify microRNAs that regulate inflammation during the development of ulcerative colitis (UC) and progression to colitis-associated colon cancer (CAC). METHODS: We performed a quantitative polymerase chain reaction analysis to measure microRNAs in 401 colon specimens from patients with UC, Crohn's disease, irritable bowel syndrome, sporadic colorectal cancer, or CAC, as well as subjects without these disorders (controls); levels were correlated with clinical features and disease activity of patients. Colitis was induced in mice by administration of dextran sodium sulfate (DSS), and carcinogenesis was induced by addition of azoxymethane; some mice also were given an inhibitor of microRNA214 (miR214). RESULTS: A high-throughput functional screen of the human microRNAome found that miR214 regulated the activity of nuclear factor-κB. Higher levels of miR214 were detected in colon tissues from patients with active UC or CAC than from patients with other disorders or controls and correlated with disease progression. Bioinformatic and genome-wide profile analyses showed that miR214 activates an inflammatory response and is amplified through a feedback loop circuit mediated by phosphatase and tensin homolog (PTEN) and PDZ and LIM domain 2 (PDLIM2). Interleukin-6 induced signal transducer and activator of transcription 3 (STAT3)-mediated transcription of miR214. A miR214 chemical inhibitor blocked this circuit and reduced the severity of DSS-induced colitis in mice, as well as the number and size of tumors that formed in mice given azoxymethane and DSS. In fresh colonic biopsy specimens from patients with active UC, the miR214 inhibitor reduced inflammation by increasing levels of PDLIM2 and PTEN. CONCLUSIONS: Interleukin-6 up-regulates STAT3-mediated transcription of miR214 in colon tissues, which reduces levels of PDLIM2 and PTEN, increases phosphorylation of AKT, and activates nuclear factor-κB. The activity of this circuit correlates with disease activity in patients with UC and progression to colorectal cancer.

Allogeneic Bone Marrow-Derived Mesenchymal Stromal Cells Promote Healing of Refractory Perianal Fistulas in Patients With Crohn's Disease.

BACKGROUND & AIMS: Patients with perianal fistulizing Crohn's disease have a poor prognosis because these lesions do not heal well. We evaluated the effects of local administration of bone marrow-derived mesenchymal stromal cells (MSCs) to these patients from healthy donors in a double-blind, placebo-controlled study. METHODS: Twenty-one patients with refractory perianal fistulizing Crohn's disease were randomly assigned to groups given injections of 1 × 10(7) (n = 5, group 1), 3 × 10(7) (n = 5, group 2), or 9 × 10(7) (n = 5, group 3) MSCs, or placebo (solution with no cells, n = 6), into the wall of curettaged fistula, around the trimmed and closed internal opening. The primary outcome, fistula healing, was determined by physical examination 6, 12, and 24 weeks later; healing was defined as absence of discharge and <2 cm of fluid collection-the latter determined by magnetic resonance imaging at week 12. All procedures were performed at Leiden University Medical Center, The Netherlands, from June 2012 through July 2014. RESULTS: No adverse events were associated with local injection of any dose of MSCs. Healing at week 6 was observed in 3 patients in group 1 (60.0%), 4 patients in group 2 (80.0%), and 1 patient in group 3 (20.0%), vs 1 patient in the placebo group (16.7%) (P = .08 for group 2 vs placebo). At week 12, healing was observed in 2 patients in group 1 (40.0%), 4 patients in group 2 (80.0%), and 1 patient in group 3 (20.0%), vs 2 patients in the placebo group (33.3%); these effects were maintained until week 24 and even increased to 4 (80.0%) in group 1. At week six, 4 of 9 individual fistulas had healed in group 1 (44.4%), 6 of 7 had healed in group 2 (85.7%), and 2 of 7 had healed in group 3 (28.6%) vs 2 of 9 (22.2%) in the placebo group (P = .04 for group 2 vs placebo). At week twelve, 3 of 9 individual fistulas had healed in group 1 (33.3%), 6 of 7 had healed in group 2 (85.7%), 2 of 7 had healed in group 3 (28.6%), and 3 of 9 had healed in the placebo group (33.3%). These effects were stable through week 24 and even increased to 6 of 9 (66.7%) in group 1 (P = .06 group 2 vs placebo, weeks 12 and 24). CONCLUSIONS: Local administration of allogeneic MSCs was not associated with severe adverse events in patients with perianal fistulizing Crohn's disease. Injection of 3 × 10(7) MSCs appeared to promote healing of perianal fistulas. ClinicalTrials.gov ID NCT01144962.

Copeptin is an independent prognostic factor for transplant-free survival in cirrhosis.

BACKGROUND & AIMS: Copeptin is a stable cleavage product of the arginine vasopressin (AVP) precursor and is equimolarly secreted with AVP. Copeptin is currently considered a reliable prognostic marker in a wide variety of diseases other than cirrhosis. We aimed to investigate the association between severity of cirrhosis and copeptin concentrations and to confirm whether copeptin is of prognostic significance in cirrhosis. METHODS: One hundred and eighty-four cirrhotic patients hospitalized in two tertiary referral centres were studied. Serum copeptin was measured in samples obtained at hospital admission. Differences in serum copeptin between Child-Pugh classes were evaluated using the Kruskal-Wallis test. Cox proportional hazard regression and Kaplan-Meier analyses were performed to evaluate associations of copeptin and other possible prognostic factors with 6- and 12-month mortality. RESULTS: Median serum copeptin (interquartile range) increased significantly through Child-Pugh classes A [5.4 (3.1-10.7) pmol/L], B [9.6 (6.0-17.3) pmol/L] and C [13.8 (5.8-34.1) pmol/L, P < 0.01]. Patients with serum copeptin >12.3 pmol/L displayed significantly higher mortality rates at 6 and 12 months as compared to those with serum copeptin ≤12.3 pmol/L (Log-rank test: P < 0.01). Serum copeptin >12.3 pmol/L was significantly associated with mortality, particularly at 6 months, independently of age, clinical parameters and Model for End stage Liver Disease (MELD), MELD-sodium and Child-Pugh score. CONCLUSIONS: Serum copeptin concentration increases significantly along with the severity of cirrhosis as defined by the Child-Pugh classification. A high serum copeptin concentration predicts survival, particularly at 6 months, independently of liver-specific scoring systems in a heterogeneous population of hospitalized cirrhotic patients.

Loss of SMAD4 alters BMP signaling to promote colorectal cancer cell metastasis via activation of Rho and ROCK.

BACKGROUND & AIMS: SMAD4 frequently is lost from colorectal cancers (CRCs), which is associated with the development of metastases and a poor prognosis. SMAD4 loss is believed to alter transforming growth factor ß signaling to promote tumor progression. However, SMAD4 is also a central component of the bone morphogenetic protein (BMP) signaling pathway, implicated in CRC pathogenesis by human genetic studies. We investigated the effects of alterations in BMP signaling on the invasive and metastatic abilities of CRC cells and changes in members in this pathway in human tumor samples. METHODS: We activated BMP signaling in SMAD4-positive and SMAD4-negative CRC cells (HCT116, HT-29, SW480, and LS174T); SMAD4 was stably expressed or knocked down using lentiviral vectors. We investigated the effects on markers of epithelial-mesenchymal transition and on cell migration, invasion, and formation of invadopodia. We performed kinase activity assays to characterize SMAD4-independent BMP signaling and used an inhibitor screen to identify pathways that regulate CRC cell migration. We investigated the effects of the ROCK inhibitor Y-27632 in immunocompromised (CD-1 Nu) mice with orthotopic metastatic tumors. Immunohistochemistry was used to detect BMPR1a, BMPR1b, BMPR2, and SMAD4 in human colorectal tumors; these were related to patient survival times. RESULTS: Activation of BMP signaling in SMAD4-negative cells altered protein and messenger RNA levels of markers of epithelial-mesenchymal transition and increased cell migration, invasion, and formation of invadopodia. Knockdown of the BMP receptor in SMAD4-negative cells reduced their invasive activity in vitro. SMAD4-independent BMP signaling activated Rho signaling via ROCK and LIM domain kinase (LIMK). Pharmacologic inhibition of ROCK reduced metastasis of colorectal xenograft tumors in mice. Loss of SMAD4 from colorectal tumors has been associated with reduced survival time; we found that this association is dependent on the expression of BMP receptors but not transforming growth factor ß receptors. CONCLUSIONS: Loss of SMAD4 from colorectal cancer cells causes BMP signaling to switch from tumor suppressive to metastasis promoting. Concurrent loss of SMAD4 and normal expression of BMP receptors in colorectal tumors was associated with reduced survival times of patients. Reagents that interfere with SMAD4-independent BMP signaling, such as ROCK inhibitors, might be developed as therapeutics for CRC.

Genome-wide association study identifies variants associated with autoimmune hepatitis type 1.

BACKGROUND & AIMS: Autoimmune hepatitis (AIH) is an uncommon autoimmune liver disease of unknown etiology. We used a genome-wide approach to identify genetic variants that predispose individuals to AIH. METHODS: We performed a genome-wide association study of 649 adults in The Netherlands with AIH type 1 and 13,436 controls. Initial associations were further analyzed in an independent replication panel comprising 451 patients with AIH type 1 in Germany and 4103 controls. We also performed an association analysis in the discovery cohort using imputed genotypes of the major histocompatibility complex region. RESULTS: We associated AIH with a variant in the major histocompatibility complex region at rs2187668 (P = 1.5 × 10(-78)). Analysis of this variant in the discovery cohort identified HLA-DRB1*0301 (P = 5.3 × 10(-49)) as a primary susceptibility genotype and HLA-DRB1*0401 (P = 2.8 × 10(-18)) as a secondary susceptibility genotype. We also associated AIH with variants of SH2B3 (rs3184504, 12q24; P = 7.7 × 10(-8)) and CARD10 (rs6000782, 22q13.1; P = 3.0 × 10(-6)). In addition, strong inflation of association signal was found with single-nucleotide polymorphisms associated with other immune-mediated diseases, including primary sclerosing cholangitis and primary biliary cirrhosis, but not with single-nucleotide polymorphisms associated with other genetic traits. CONCLUSIONS: In a genome-wide association study, we associated AIH type 1 with variants in the major histocompatibility complex region, and identified variants of SH2B3and CARD10 as likely risk factors. These findings support a complex genetic basis for AIH pathogenesis and indicate that part of the genetic susceptibility overlaps with that for other immune-mediated liver diseases.

High peak alanine aminotransferase determines extra risk for nonanastomotic biliary strictures after liver transplantation with donation after circulatory death.

Orthotopic liver transplantation (OLT) with donation after circulatory death (DCD) often leads to a higher first week peak alanine aminotransferase (ALT) and a higher rate of biliary nonanastomotic strictures (NAS) as compared to donation after brain death (DBD). This retrospective study was to evaluate whether an association exists between peak ALT and the development of NAS in OLT with livers from DBD (n = 399) or DCD (n = 97) from two transplantation centers. Optimal cutoff value of peak ALT for risk of development of NAS post-DCD-OLT was 1300 IU/l. The 4-year cumulative incidence of NAS after DCD-OLT was 49.5% in patients with a high ALT peak post-OLT, compared with 11.3% in patients with a low ALT peak. (P < 0.001). No relation between peak ALT and NAS was observed after DBD-OLT. Multivariate analysis revealed peak ALT ≥1300 IU/l [adjusted hazard ratio (aHR) = 3.71, confidence interval (CI) (1.26-10.91)] and donor age [aHR = 1.04, CI 1.00-1.07] to be independently associated with development of NAS post-DCD-OLT. A peak ALT of <1300 IU/l carries a risk for NAS similar to DBD-OLT. Thus, in DCD-OLT, but not in DBD-OLT, peak ALT discriminates patients at high or low risk for NAS.

Collagen degradation and neutrophilic infiltration: a vicious circle in inflammatory bowel disease.

OBJECTIVE: Proline-glycine-proline (PGP) has been shown to have chemotactic effects on neutrophils via CXCR2 in several lung diseases. PGP is derived from collagen by the combined action of matrix metalloproteinase (MMP) 8 and/or MMP9 and prolyl endopeptidase (PE). We investigated the role of PGP in inflammatory bowel disease (IBD). DESIGN: In intestinal tissue from patients with IBD and mice with dextran sodium sulfate (DSS)-induced colitis, MMP8, MMP9 and PE were evaluated by ELISA, immunoblot and immunohistochemistry. Peripheral blood polymorphonuclear cell (PMN) supernatants were also analysed accordingly and incubated with collagen to assess PGP generation ex vivo. PGP levels were measured by mass spectrometry, and PGP neutralisation was achieved with a PGP antagonist and PGP antibodies. RESULTS: In the intestine of patients with IBD, MMP8 and MMP9 levels were elevated, while PE was expressed at similar levels to control tissue. PGP levels were increased in intestinal tissue of patients with IBD. Similar results were obtained in intestine from DSS-treated mice. PMN supernatants from patients with IBD were far more capable of generating PGP from collagen ex vivo than healthy controls. Furthermore, PGP neutralisation during DSS-induced colitis led to a significant reduction in neutrophil infiltration in the intestine. CONCLUSIONS: The proteolytic cascade that generates PGP from collagen, as well as the tripeptide itself, is present in the intestine of patients with IBD and mice with DSS-induced colitis. PGP neutralisation in DSS-treated mice showed the importance of PGP-guided neutrophilic infiltration in the intestine and indicates a vicious circle in neutrophilic inflammation in IBD.

Genetic and microbial factors modulating the ubiquitin proteasome system in inflammatory bowel disease.

OBJECTIVE: Altered microbiota composition, changes in immune responses and impaired intestinal barrier functions are observed in IBD. Most of these features are controlled by proteases and their inhibitors to maintain gut homeostasis. Unrestrained or excessive proteolysis can lead to pathological gastrointestinal conditions. The aim was to validate the identified protease IBD candidates from a previously performed systematic review through a genetic association study and functional follow-up. DESIGN: We performed a genetic association study in a large multicentre cohort of patients with Crohn's disease (CD) and UC from five European IBD referral centres in a total of 2320 CD patients, 2112 UC patients and 1796 healthy controls. Subsequently, we did an extensive functional assessment of the candidate genes to explore their causality in IBD pathogenesis. RESULTS: Ten single nucleotide polymorphisms (SNPs) in four genes were significantly associated with CD: CYLD, USP40, APEH and USP3. CYLD was the most significant gene with the intronically located rs12324931 the strongest associated SNP (p(FDR)=1.74e-17, OR=2.24 (1.83 to 2.74)). Five SNPs in four genes were significantly associated with UC: USP40, APEH, DAG1 and USP3. CYLD, as well as some of the other associated genes, is part of the ubiquitin proteasome system (UPS). We therefore determined if the IBD-associated adherent-invasive Escherichia coli (AIEC) can modulate the UPS functioning. Infection of intestinal epithelial cells with the AIEC LF82 reference strain modulated the UPS turnover by reducing poly-ubiquitin conjugate accumulation, increasing 26S proteasome activities and decreasing protein levels of the NF-κB regulator CYLD. This resulted in IκB-α degradation and NF-κB activation. This activity was very important for the pathogenicity of AIEC since decreased CYLD resulted in increased ability of AIEC LF82 to replicate intracellularly. CONCLUSIONS: Our results reveal the UPS, and CYLD specifically, as an important contributor to IBD pathogenesis, which is favoured by both genetic and microbial factors.

MMP-2 is a disease-modifying gene in primary sclerosing cholangitis.

BACKGROUND: Primary sclerosing cholangitis (PSC) is a chronic inflammatory disease of the bile ducts, frequently necessitating orthotopic liver transplantation (OLT), often accompanied by inflammatory bowel disease (IBD). Matrix metalloproteinases (MMPs) are associated with fibrotic diseases caused by the involvement in tissue remodelling. AIM: To evaluate the contribution of MMP-2 and -9 promoter polymorphisms to disease severity in PSC, as assessed by death or need for OLT. METHODS: Matrix metalloproteinase-2 (-1306 C/T) and -9 (-1562 C/T) gene promoter polymorphisms were analyzed in 132 PSC patients. Follow-up was from onset PSC until death, OLT or end of follow-up. RESULTS: Twenty-year cumulative incidence (CI) of death or OLT for PSC patients with MMP-2 CT genotype was 86.5% compared to 52.8% for CC genotype (P = 0.030) and reached 100% at 11.3 years for TT genotype. In patients with IBD, CIs were similar: 20-years CI of death or OLT for MMP-2 CT genotype was 86.0% compared to 49.0% for CC genotype and 100% at 11.3 years for TT genotype. Patients without IBD showed a similar trend in 20 years CI for MMP-2 CT (77.8%) compared to CC (57.8%) and CI for TT genotype reached 100% at 9.3 years. Multivariate analysis showed, along with age at diagnosis, a stepwise increase in hazard ratio for MMP-2 T-allele polymorphism for death or OLT. MMP-9 genotype was not associated with disease severity in PSC. CONCLUSION: Matrix metalloproteinase-2 C to T-1306 gene promoter polymorphism in PSC is an independent risk factor for disease severity as reflected by the need for OLT or disease progression leading to mortality.

Hedgehog signalling stimulates precursor cell accumulation and impairs epithelial maturation in the murine oesophagus.

OBJECTIVE: In the intestine Hedgehog (Hh) signalling is directed from epithelium to mesenchyme and negatively regulates epithelial precursor cell fate. The role of Hh signalling in the oesophagus has not been studied in vivo. Here the authors examined the role of Hh signalling in epithelial homeostasis of oesophagus. DESIGN: The authors used transgenic mice in which the Hh receptor Patched1 (Ptch1) could be conditionally inactivated in a body-wide manner and mice in which Gli1 could be induced specifically in the epithelium of the skin and oesophagus. Effects on epithelial homeostasis of the oesophagus were examined using immunohistochemistry, in situ hybridisation, transmission electron microscopy and real-time PCR. Hh signalling was examined in patients with oesophageal squamous cell carcinoma (SCC) by quantitative real-time PCR. RESULTS: Sonic Hh is signalled in an autocrine manner in the basal layer of the oesophagus. Activation of Hh signalling resulted in an expansion of the epithelial precursor cell compartment and failure of epithelial maturation and migration. Levels of Hh targets GLI1, HHIP and PTCH1 were increased in SCC compared with normal tissue from the same patients. CONCLUSION: Here the authors find that Hh signalling positively regulates the precursor cell compartment in the oesophageal epithelium in an autocrine manner. Since Hh signalling targets precursor cells in the oesophageal epithelium and signalling is increased in SCCs, Hh signalling may be involved in oesophageal SCC formation.