0000000000076144

AUTHOR

Christoph Schramm

The Transcription Factor Promyelocytic Leukemia Zinc Finger Protein Is Associated With Expression of Liver‐Homing Receptors on Human Blood CD56bright Natural Killer Cells

The transcription factor promyelocytic leukemia zinc finger protein (PLZF) is involved in the development of natural killer (NK) cells and innate lymphoid cells, including liver‐resident NK cells in mice. In human NK cells, the role of PLZF in liver residency is still unknown. Expression of PLZF in matched human peripheral blood‐ and liver‐derived NK cells and the association of PLZF expression with surface molecules and transcription factors relevant for tissue residency were investigated using multiparameter flow cytometry and assessing single‐cell messenger RNA (mRNA) levels. Intrahepatic cluster of differentiation (CD)56bright NK cells expressed significantly higher levels of PLZF than …

research product

Genetic association analysis identifies variants associated with disease progression in primary sclerosing cholangitis

ObjectivePrimary sclerosing cholangitis (PSC) is a genetically complex, inflammatory bile duct disease of largely unknown aetiology often leading to liver transplantation or death. Little is known about the genetic contribution to the severity and progression of PSC. The aim of this study is to identify genetic variants associated with PSC disease progression and development of complications.DesignWe collected standardised PSC subphenotypes in a large cohort of 3402 patients with PSC. After quality control, we combined 130 422 single nucleotide polymorphisms of all patients—obtained using the Illumina immunochip—with their disease subphenotypes. Using logistic regression and Cox proportiona…

research product

Simplified criteria for the diagnosis of autoimmune hepatitis

Diagnosis of autoimmune hepatitis (AIH) may be challenging. However, early diagnosis is important because immunosuppression is life-saving. Diagnostic criteria of the International Autoimmune Hepatitis Group (IAIHG) were complex and purely meant for scientific purposes. This study of the IAIHG aims to define simplified diagnostic criteria for routine clinical practice. Candidate criteria included sex, age, autoantibodies, immunoglobulins, absence of viral hepatitis, and histology. The training set included 250 AIH patients and 193 controls from 11 centers worldwide. Scores were built from variables showing predictive ability in univariate analysis. Diagnostic value of each score was assesse…

research product

Long-term outcome after living donor liver transplantation compared to donation after brain death in autoimmune liver diseases: Experience from the European Liver Transplant Registry.

Knowledge of living donor liver transplantation (LDLT) for autoimmune liver diseases (AILDs) is scarce. This study analyzed survival in LDLT recipients registered in the European Liver Transplant Registry with autoimmune hepatitis, primary biliary cholangitis, primary sclerosing cholangitis (PSC) and the non-autoimmune disorder alcohol-related cirrhosis. In total, 29 902 individuals enrolled between 1998 and 2017 were analyzed, including 1003 with LDLT. Survival from >90 days after LDLT for AILDs in adults was 85.5%, 74.2%, and 58.0% after 5, 10, and 15 years. Adjusted for recipient age, sex, and liver transplantation era, adult PSC patients receiving LDLT showed increased mortality compare…

research product

TGF-beta regulates airway responses via T cells.

Abstract Allergic asthma is characterized by airway hyperreactivity, inflammation, and a Th2-type cytokine profile favoring IgE production. Beneficial effects of TGF-β and conflicting results regarding the role of Th1 cytokines have been reported from murine asthma models. In this study, we examined the T cell as a target cell of TGF-β-mediated immune regulation in a mouse model of asthma. We demonstrate that impairment of TGF-β signaling in T cells of transgenic mice expressing a dominant-negative TGF-β type II receptor leads to a decrease in airway reactivity in a non-Ag-dependent model. Increased serum levels of IFN-γ can be detected in these animals. In contrast, after injection of OVA …

research product

Dense genotyping of immune-related disease regions identifies nine new risk loci for primary sclerosing cholangitis

To access publisher's full text version of this article click on the hyperlink at the bottom of the page Primary sclerosing cholangitis (PSC) is a severe liver disease of unknown etiology leading to fibrotic destruction of the bile ducts and ultimately to the need for liver transplantation. We compared 3,789 PSC cases of European ancestry to 25,079 population controls across 130,422 SNPs genotyped using the Immunochip. We identified 12 genome-wide significant associations outside the human leukocyte antigen (HLA) complex, 9 of which were new, increasing the number of known PSC risk loci to 16. Despite comorbidity with inflammatory bowel disease (IBD) in 72% of the cases, 6 of the 12 loci sh…

research product

Involvement of distal airways in a chronic model of experimental asthma.

Summary Background Bronchial asthma is characterized by chronic airway inflammation and airway remodelling which occurs in both proximal and distal airways. These changes are associated with development of airway hyper-responsiveness and airflow limitation. Objective This study was aimed to analyse whether chronic inhalative allergen challenges in mice lead to morphological and physiological changes comparable with this phenotype. Methods For this purpose, BALB/c mice were systemically sensitized to ovalbumin (OVA) followed by aerosol allergen challenges on 2 consecutive days per week for 12 weeks. Results In chronically challenged mice, tissue inflammation in proximal as well as distal air…

research product

102 NOVEL SUSCEPTIBILITY LOCI FOR PRIMARY SCLEROSING CHOLANGITIS IDENTIFIED BY GENOME-WIDE ASSOCIATION AND REPLICATION ANALYSIS

research product

The objective of our study was to determine the regulatory effects that endogenous transforming growth factor β (TGFβ) exerts on T cells in the pathogenesis of collagen-induced arthritis (CIA). CIA was induced in transgenic mice expressing a dominant negative TGFβ type II receptor in T cells under the control of the human CD2 promoter. Clinical and histological arthritis scores were determined and experiments on disease induction and the healing phase of disease were performed. The proliferation and cytokine production of draining lymph node cells in vitro were analyzed. Transgenic mice were more susceptible to induction of CIA. The overall incidence was higher in transgenic mice than in wi…

research product

Susceptibility to collagen-induced arthritis is modulated by TGFβ responsiveness of T cells

The objective of our study was to determine the regulatory effects that endogenous transforming growth factor beta (TGFbeta) exerts on T cells in the pathogenesis of collagen-induced arthritis (CIA). CIA was induced in transgenic mice expressing a dominant negative TGFbeta type II receptor in T cells under the control of the human CD2 promoter. Clinical and histological arthritis scores were determined and experiments on disease induction and the healing phase of disease were performed. The proliferation and cytokine production of draining lymph node cells in vitro were analyzed. Transgenic mice were more susceptible to induction of CIA. The overall incidence was higher in transgenic mice t…

research product

Mutational Characterization of the Bile Acid Receptor TGR5 in Primary Sclerosing Cholangitis

Background: TGR5, the G protein-coupled bile acid receptor 1 (GPBAR1), has been linked to inflammatory pathways as well as bile homeostasis, and could therefore be involved in primary sclerosing cholangitis (PSC) a chronic inflammatory bile duct disease. We aimed to extensively investigate TGR5 sequence variation in PSC, as well as functionally characterize detected variants.Methodology/Principal Findings: Complete resequencing of TGR5 was performed in 267 PSC patients and 274 healthy controls. Six nonsynonymous mutations were identified in addition to 16 other novel single-nucleotide polymorphisms. To investigate the impact from the nonsynonymous variants on TGR5, we created a receptor mod…

research product

Inflammation and remodelling of distal airways in a murine model of chronic experimental asthma

research product

Cutting Edge: TGF-β Signaling Is Required for the In Vivo Expansion and Immunosuppressive Capacity of Regulatory CD4+CD25+ T Cells

Abstract Data regarding the role of TGF-β for the in vivo function of regulatory CD4+CD25+ T cells (Treg) are controversial. A transgenic mouse model with impaired TGF-β signaling specifically in T cells was used to assess the role of endogenous TGF-β for the in vivo function of CD4+CD25+ Treg in a murine model of colitis induced by dextran sulfate. Transfer of wild-type, but not transgenic CD4+CD25+ Treg was found to suppress colitis in wild-type mice. In addition, by transferring CFSE-labeled CD4+CD25+ Treg we could demonstrate that endogenous TGF-β promotes the expansion of CD4+CD25+ Treg in vivo. Transgenic mice themselves developed reduced numbers of peripheral CD4+CD25+ Treg and were …

research product

TGF-β Suppresses Tumor Progression in Colon Cancer by Inhibition of IL-6 trans-Signaling

Alterations of TGF-beta signaling have been described in colorectal cancer, although the molecular consequences are largely unknown. By using transgenic mice overexpressing TGF-beta or a dominant-negative TGF-betaRII, we demonstrate that TGF-beta signaling in tumor infiltrating T lymphocytes controls the growth of dysplastic epithelial cells in experimental colorectal cancer, as determined by histology and a novel system for high-resolution chromoendoscopy. At the molecular level, TGF-beta signaling in T cells regulated STAT-3 activation in tumor cells via IL-6. IL-6 signaling required tumor cell-derived soluble IL-6R rather than membrane bound IL-6R and suppression of such TGF-beta-depende…

research product

Longterm Survival After Liver Transplantation for Autoimmune Hepatitis : Results From the European Liver Transplant Registry

The aim of this study was to analyze longterm patient and graft survival after liver transplantation for autoimmune hepatitis (AIH-LT) from the prospective multicenter European Liver Transplant Registry. Patient and liver graft survival between 1998 and 2017 were analyzed. Patients after AIH-LT (n = 2515) were compared with patients receiving LT for primary biliary cholangitis (PBC-LT; n = 3733), primary sclerosing cholangitis (PSC-LT; n = 5155), and alcohol-related cirrhosis (AC-LT; n = 19,567). After AIH-LT, patient survival was 79.4%, 70.8%, and 60.3% and graft survival was 73.2%, 63.4%, and 50.9% after 5, 10, and 15 years of follow-up. Overall patient survival was similar to patients af…

research product

Coexpression of TGF-β1 and IL-10 Enables Regulatory T Cells to Completely Suppress Airway Hyperreactivity

Abstract In allergic airway disease, Treg may play an important role in the modulation of airway hyperreactivity (AHR) and inflammation. We therefore investigated the therapeutic potential of Treg in an Ag-dependent murine asthma model. We here describe that AHR can be completely suppressed by adoptive transfer of Treg overexpressing active TGF-β1. Using mice with impaired TGF-β signaling in T cells, we could demonstrate that TGF-β signaling in recipient effector T cells or transferred Treg themselves is not required for the protective effects on AHR. However, the expression of IL-10 by Treg was found to be essential for the suppression of AHR, since Treg overexpressing active TGF-β1 but de…

research product

Extended analysis of a genome-wide association study in primary sclerosing cholangitis detects multiple novel risk loci

Background & Aims: A limited number of genetic risk factors have been reported in primary sclerosing cholangitis (PSC). To discover further genetic susceptibility factors for PSC, we followed up on,a second tier of single nucleotide polymorphisms (SNPs) from a genome-wide association study (GWAS). Methods: We analyzed 45 SNPs in 1221 PSC cases and 3508 controls. The association results from the replication analysis and the original GWAS (715 PSC cases and 2962 controls) were combined in a meta-analysis comprising 1936 PSC cases and 6470 controls. We performed an analysis of bile microbial community composition in 39 PSC patients by 16S rRNA sequencing. Results: Seventeen SNPs representing 1…

research product

Genome-Wide Association Analysis in Primary Sclerosing Cholangitis

Background & Aims We aimed to characterize the genetic susceptibility to primary sclerosing cholangitis (PSC) by means of a genome-wide association analysis of single nucleotide polymorphism (SNP) markers. Methods A total of 443,816 SNPs on the Affymetrix SNP Array 5.0 (Affymetrix, Santa Clara, CA) were genotyped in 285 Norwegian PSC patients and 298 healthy controls. Associations detected in this discovery panel were re-examined in independent case-control panels from Scandinavia (137 PSC cases and 368 controls), Belgium/The Netherlands (229 PSC cases and 735 controls), and Germany (400 cases and 1832 controls). Results The strongest associations were detected near HLA-B at chromosome 6p21…

research product

TGFbeta regulates the CD4+CD25+ T-cell pool and the expression of Foxp3 in vivo.

Factors influencing the development of CD4+CD25+ T-cells in vivo are poorly understood. In order to investigate the contribution of TGFbeta1 to the development and function of CD4+CD25+ T-cells, we generated a gain of function mutation resulting in the overexpression of an active form of TGFbeta1 in T-cells under control of the human CD2 promoter. In peripheral lymphoid organs and in the thymus, the frequency of CD4+CD25+ T-cells was increased in transgenic mice. This appeared to be due to an autocrine effect of TGFbeta on T-cells, since concomitant impairment of TGFbeta-signaling in double transgenic mice resulted in a phenotype similar to wild type. In contrast, in single transgenic mice …

research product

Rapid development of Epstein-Barr virus-associated Hodgkin's disease after cessation of foscarnet therapy in an HIV-infected patient.

Epidemiological features suggest a link between Hodgkin's disease (HD) and Epstein-Barr virus (EBV) infection1. Indeed, EBV genome and expression of latent antigens can be found in Reed-Sternberg cells. In the majority of cases HD in HIV patients seems to be EBV-associated. We report on a 51-year-old HIV-infected patient in whom EBV-positive HD of mixed cellularity rapidly developed within one month after cessation of treatment with intravenous foscarnet.

research product

Autoimmune hepatitis in the elderly.

Abstract OBJECTIVES: Autoimmune hepatitis (AIH) is widely believed to be a disease of young women and menopause. Little is known about the frequency and clinical characteristics in patients aged ≥65 yr. METHODS: We reviewed charts of 120 consecutive outpatients with known AIH to identify patients who were diagnosed at the age of 65 or older. These 20 patients (median age, 69 yr) were compared to the same number of younger patients (median age, 24 yr) with well-documented AIH from the same cohort. RESULTS: Seventeen percent (20/120) of our patients were ≥65 yr at the time of diagnosis. In the older patients median time to diagnosis was significantly longer than in the younger patients (8.5 >…

research product

P38 MAP Kinase Signaling Is Required for the Conversion of CD4+CD25− T Cells into iTreg

CD4+CD25+ regulatory T cells (Treg) are important mediators of immune tolerance. A subset of Treg can be generated in the periphery by TGF-beta dependent conversion of conventional CD4+CD25− T cells into induced Treg (iTreg). In chronic viral infection or malignancy, such induced iTreg, which limit the depletion of aberrant or infected cells, may be of pathogenic relevance. To identify potential targets for therapeutic intervention, we investigated the TGF-beta signaling in Treg. In contrast to conventional CD4+ T cells, Treg exhibited marked activation of the p38 MAP kinase pathway. Inhibition of p38 MAP kinase activity prevented the TGF-beta-dependent conversion of CD4+CD25− T cells into …

research product

Liver stiffness measurement by vibration-controlled transient elastography improves outcome prediction in primary biliary cholangitis

BACKGROUND & AIMS: Liver stiffness measurement (LSM) by vibration-controlled transient elastography (VCTE) has been shown to predict outcomes of patients with primary biliary cholangitis (PBC) in small-size studies. We aimed to validate the prognostic value of LSM in a large cohort study. METHODS: We performed an international, multicentre, retrospective follow-up study of 3,985 patients with PBC seen at 23 centres in 12 countries. Eligibility criteria included at least 1 reliable LSM by VCTE and a follow-up ≥ 1 year. Independent derivation (n = 2,740) and validation (n = 568) cohorts were built. The primary endpoint was time to poor clinical outcomes defined as liver-related complications,…

research product

Combined Therapy with Azathioprine, Prednisolone, and Ursodiol in Patients with Primary Sclerosing Cholangitis: A Case Series

No established medical therapy alters the progressive course of primary sclerosing cholangitis.To explore the potential usefulness of combined therapy with azathioprine, steroids and ursodeoxycholic acid (UDCA) in primary sclerosing cholangitis.Case series.University hospital in Mainz, Germany.15 patients with primary sclerosing cholangitis.Azathioprine (1 to 1.5 mg/kg of body weight per day), prednisolone (1 mg/kg per day initially, tapering to 5 to 10 mg per day) and UDCA (500 to 750 mg per day).Clinical and laboratory evaluation, liver biopsy, and endoscopic retrograde cholangiography (a30% change in stenosis was considered significant).After a median observation period of 41 months (ran…

research product

Impairment of TGF-β signaling in T cells increases susceptibility to experimental autoimmune hepatitis in mice

In autoimmune hepatitis, strong TGF-beta1 expression is found in the inflamed liver. TGF-beta overexpression may be part of a regulatory immune response attempting to suppress autoreactive T cells. To test this hypothesis, we determined whether impairment of TGF-beta signaling in T cells leads to increased susceptibility to experimental autoimmune hepatitis (EAH). Transgenic mice of strain FVB/N were generated expressing a dominant-negative TGF-beta type II receptor in T cells under the control of the human CD2 promoter/locus control region. On induction of EAH, transgenic mice showed markedly increased portal and periportal leukocytic infiltrations with hepatocellular necroses compared wit…

research product

Genome-wide association analysis in primary sclerosing cholangitis identifies two non-HLA susceptibility loci

Primary sclerosing cholangitis (PSC) is a chronic bile duct disease affecting 2.4-7.5% of individuals with inflammatory bowel disease. We performed a genome-wide association analysis of 2,466,182 SNPs in 715 individuals with PSC and 2,962 controls, followed by replication in 1,025 PSC cases and 2,174 controls. We detected non-HLA associations at rs3197999 in MST1 and rs6720394 near BCL2L11 (combined P = 1.1 x 10(-16) and P = 4.1 x 10(-8), respectively).

research product

S2k-Leitlinie nicht alkoholische Fettlebererkrankungen

research product

Pregnancy in primary sclerosing cholangitis

Background There is a paucity of data on fertility or pregnancy in patients with primary sclerosing cholangitis (PSC). Objective To assess fertility in PSC by comparing the number of children in a large cohort of PSC patients to healthy controls and to investigate the outcome of pregnancy, as well as the influence of pregnancy on the disease course. Design Case series. Setting Germany. Participants 229 PSC patients and 569 healthy controls were evaluated for the number of children. 17 patients with PSC and at least one pregnancy, or who received a diagnosis of PSC within 6 months after delivery, were included in the more detailed analysis. Main outcome measures Number of children per patien…

research product

Autoimmune Lebererkrankungen: Diagnostik und Therapie

Autoimmune Hepatitis (AIH), primary biliary cirrhosis (PBC), primary sclerosing cholangitis (PSC) and overlap syndromes of these three disease entities are regarded as autoimmune liver diseases. These conditions are important differential diagnoses of elevated liver function tests as about 10 % of liver transplantations in Europe and North America are for these indications. The diagnosis is often difficult but can be facilitated by sequential measurement of relevant autoantibodies, exclusion of other liver disease, ultrasound, ERCP and liver histology. In AIH immunosuppressive therapy has been shown to prevent or stop the development of cirrhosis and improve the prognosis of the patients de…

research product

Thiamine for the treatment of nucleoside analogue-induced severe lactic acidosis

Nucleoside analogue-induced lactic acidosis is an often fatal condition in patients with HIV. There is only one report of successful treatment with riboflavin. We describe a 30-year-old female with AIDS and nucleoside analogue-induced lactic acidosis that exacerbated shortly after introducing total parenteral nutrition and reversed within hours after the addition of thiamine. Successful treatment of nucleoside analogue-induced lactic acidosis with a high dose of thiamine supports the hypothesis that vitamin deficiency is an important cofactor in the development of this rare and unpredictable condition in patients with HIV. We suggest that high dose B-vitamins should be given to any patient …

research product

1124 FERTILITY AND PREGNANCY IN PRIMARY SCLEROSING CHOLANGITIS

research product