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1.
J Hepatol ; 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31954207

RESUMEN

BACKGROUND & AIMS: Hepatic innate immune control of viral infections has largely been attributed to Kupffer cells, the liver macrophages. However, also hepatocytes, the parenchymal cells of the liver, possess potent immunological functions in addition to their known metabolic functions. Owing to their abundance in the liver and known immunological functions, we aimed to investigate the direct anti-viral mechanisms employed by hepatocytes. METHODS: Using lymphocytic choriomeningitis virus (LCMV) as a model of liver infection, we first assessed the role of myeloid cells by depletion prior to infection. We investigated the role of hepatocyte-intrinsic innate immune signaling by infecting mice lacking canonical NF-κB signaling (IKKßΔHep) specifically in hepatocytes. In addition, mice lacking hepatocyte-specific interferon-α/ß signaling-(IFNARΔHep), or interferon-α/ß signaling in myeloid cells-(IFNARΔMyel) were infected. RESULTS: Here, we demonstrate that LCMV activates NF-κB signaling in hepatocytes. LCMV-triggered NF-κB activation in hepatocytes did not depend on Kupffer cells or TNFR1- but rather on TLR-signaling. LCMV-infected IKKßΔHep livers displayed strongly elevated viral titers due to LCMV accumulation within hepatocytes, reduced interferon-stimulated gene (ISG) expression, delayed intrahepatic immune cell influx and delayed intrahepatic LCMV-specific CD8+ T-cell responses. Notably, viral clearance and ISG expression were also reduced in LCMV-infected primary hepatocytes lacking IKKß, demonstrating a hepatocyte-intrinsic effect. Similar to livers of IKKßΔHep mice, enhanced hepatocytic LCMV accumulation was observed in livers of IFNARΔHep, whereas IFNARΔMyel mice were able to control LCMV-infection. Hepatocytic NF-κB signaling was also required for efficient ISG induction in HDV-infected dHepaRG cells and interferon-α/ß-mediated inhibition of HBV replication in vitro. CONCLUSIONS: Together, these data show that hepatocyte-intrinsic NF-κB is a vital amplifier of interferon-α/ß signaling pivotal for early, strong ISG responses, influx of immune cells and hepatic viral clearance.

2.
Cancer Immunol Immunother ; 68(12): 2055-2066, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31724091

RESUMEN

Immune checkpoint inhibition suggests promising progress for the treatment of advanced hepatocellular carcinoma (HCC). However, the underlying cellular mechanisms remain unclear because liver cancer cells apparently do not upregulate inhibitory checkpoint molecules. Here, we analysed whether regulatory T cells (Tregs) can alternatively trigger checkpoint inhibition pathways in HCC. Using flow cytometry we analysed expression of checkpoint molecules (PD-1, PD-L1, CTLA-4, GITR, Tim-3) on peripheral CD4+CD25+Foxp3+ Tregs and their secretion of inhibitory mediators (IL-10, IL-35, TGF-beta, galectin-9) in 116 individuals (50 patients with HCC, 41 non-tumour bearing liver disease controls, 25 healthy controls). Functional activity of Tregs on T effector cells (IFN-gamma production, cytotoxicity) was characterized in vitro using a lectin-dependent cellular cytotoxicity (LDCC) assay against checkpoint inhibitor-negative P815 target cells. Unlike liver patients without malignancy and healthy controls, the frequency of checkpoint inhibitor-positive Tregs inversely correlated to age of patients with HCC (PD-L1, p = 0.0080; CTLA-4, p = 0.0029) and corresponded to enhanced numbers of Tregs producing IL-10 and IL-35 (p < 0.05 each). Tregs inhibited IFN-gamma secretion and cytotoxicity of CD8+ T cells when added to LDCC against P815 cells. Treg-induced inhibition of IFN-gamma secretion could be partially blocked by neutralizing PD-1 and PD-L1 antibodies specifically in HCC patients. In HCC peripheral Tregs upregulate checkpoint inhibitors and contribute to systemic immune dysfunction and antitumoural activity by several inhibitory pathways, presumably facilitating tumour development at young age. Blocking PD-L1/PD-1 interactions in vitro selectively interfered with inhibitory Treg -T effector cell interactions in the patients with HCC and resulted in improved antitumoural activity also against checkpoint inhibitor-negative tumour cells.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Linfocitos T CD8-positivos/inmunología , Carcinoma Hepatocelular/inmunología , Inmunoterapia/métodos , Neoplasias Hepáticas/inmunología , Linfocitos T Reguladores/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Antígeno B7-H1/metabolismo , Citotoxicidad Inmunológica , Femenino , Humanos , Tolerancia Inmunológica , Interferón gamma/metabolismo , Activación de Linfocitos , Masculino , Persona de Mediana Edad , Receptor de Muerte Celular Programada 1/metabolismo , Adulto Joven
3.
Z Gastroenterol ; 57(11): 1309-1320, 2019 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-31739377

RESUMEN

INTRODUCTION: Lynch syndrome (LS) is the most common hereditary colorectal cancer syndrome and accounts for ~3 % of all CRCs. This autosomal dominant disorder is caused by germline mutations in DNA mismatch repair genes (MLH1, MSH2, MSH6, PMS2, and EPCAM). One in 300 individuals of the general population are considered to be mutation carriers (300 000 individuals/Germany). Mutation carriers are at a high CRC risk of 15-46 % till the age of 75 years. LS also includes a variety of extracolonic malignancies such as endometrial, small bowel, gastric, urothelial, and other cancers. METHODS: The German Consortium for Familial Intestinal Cancer consists of 14 university centers in Germany. The aim of the consortium is to develop and evaluate surveillance programs and to further translate the results in clinical care. We have revisited and updated the clinical management guidelines for LS patients in Germany. RESULTS: A surveillance colonoscopy should be performed every 12-24 months starting at the age of 25 years. At diagnosis of first colorectal cancer, an oncological resection is advised, an extended resection (colectomy with ileorectal anastomosis) has to be discussed with the patient. The lifetime risk for gastric cancer is 0.2-13 %. Gastric cancers detected during surveillance have a lower tumor stage compared to symptom-driven detection. The lifetime risk for small bowel cancer is 4-8 %. About half of small bowel cancer is located in the duodenum and occurs before the age of 35 years in 10 % of all cases. Accordingly, patients are advised to undergo an esophagogastroduodenoscopy every 12-36 months starting by the age of 25 years. CONCLUSION: LS colonic and extracolonic clinical management, surveillance and therapy are complex and several aspects remain unclear. In the future, surveillance and clinical management need to be more tailored to gene and gender. Future prospective trials are needed.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/patología , Reparación de la Incompatibilidad de ADN , Endoscopía del Sistema Digestivo/métodos , Guías de Práctica Clínica como Asunto , Conducta de Reducción del Riesgo , Neoplasias Colorrectales , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Alemania , Humanos , Vigilancia de la Población , Factores de Tiempo
4.
J Mol Med (Berl) ; 97(11): 1589-1600, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31637480

RESUMEN

The I148M variant of the Patatin-like phospholipase domain-containing 3 (PNPLA3) protein is associated with an increased risk for liver inflammation and hepatocellular carcinoma (HCC), but the underlying mechanism is unknown. We hypothesized that enhanced CXC chemokine secretion mediates hepatic inflammation that accelerates development of HCC. Expandable primary human (upcyte®) hepatocytes and human PLC/PRF/5 hepatoma cells were lentivirally transduced with both PNPLA3 I148M variants and stimulated with lipids. Cytokine levels in culture supernatant and patient sera (n = 80) were analyzed by ELISA. Supernatants were assessed in transmigration experiments, tube formation, and proliferation assays. In vitro, lipid stimulation of transduced hepatocytes dose-dependently induced the production of interleukin-8 and CXCL1 in hepatocytes carrying the PNPLA3 148M variant. In line, sera from PNPLA3 148M-positive patients with alcoholic liver cirrhosis contained higher levels of interleukin-8 and CXCL1 than patients with wild-type PNPLA3. Supernatants from lipid-stimulated hepatocytes with the PNPLA3 148M variant induced enhanced migration of white blood cells, angiogenesis, and cell proliferation in comparison with supernatants from wild-type hepatocytes via CXC receptors 1 and 2. Increased production of interleukin-8 and CXCL1 by hepatocytes carrying the PNPLA3 148M variant contributes to a pro-inflammatory and tumorigenic milieu in patients with alcoholic liver disease. KEY MESSAGES: The PNPLA3 148M variant is associated with cirrhosis and hepatocellular carcinoma. Lipid stimulation of hepatocytes with this variant induces IL-8 and CXCL1. Supernatants from hepatocytes with this variant promote migration and angiogenesis. Sera from patients with this variant contained enhanced levels of IL-8 and CXCL1. The PNPLA3 148M variant contributes to a tumorigenic milieu via IL-8 and CXCL1.

5.
Front Immunol ; 10: 1838, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31440239

RESUMEN

Background and Aims: Ascites and spontaneous bacterial peritonitis (SBP) are frequent complications of liver cirrhosis. In spite of the clinical impact, knowledge about ascites as an immune cell compartment in liver disease is limited. Therefore, we analyzed NK cells in blood, ascites, and liver. Methods: Mononuclear cells from blood, ascites, and liver explants of patients with advanced liver disease were extracted by density gradient centrifugation. Phenotyping and analysis of functional responses were carried out using flow cytometry. Migratory potential was investigated with transwell chamber assays. NK cell metabolism was assessed by Seahorse technology. Results: NK cell frequency was increased in uninfected ascites compared to blood, but not to liver. Ascites NK cells were predominantly CD16positive. CD56bright ascites NK cells did not share the typical phenotype of their liver counterparts. In contrast to the inhibitory receptor NKG2A, expression of the activating receptor NKG2D was decreased on ascites and liver CD16positive NK cells. Ascites NK cells expressed higher levels of CXCR3 than blood or liver NK cells, corresponding to increased ascites levels of CXCL10. Blood NK cells migrated toward ascites. Stimulation of mononuclear cells with Escherichia coli led to downregulation of NKG2D expression and IL-12 and IL-18 mediated secretion of interferon-γ by ascites and liver, but not blood NK cells. In-vivo, ascites NK cells expressed higher levels of the activation marker CD69 and lower levels of NKG2D during SBP compared to uninfected ascites. Conclusion: Ascites NK cells display a particular phenotype and are implicated in local immune defense against translocating bacteria.

6.
Sci Rep ; 9(1): 1439, 2019 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-30723271

RESUMEN

Hepatocarcinogenesis is tightly linked to liver fibrosis. Recently, two GWAS variants, MICA rs2596542 and DEPDC5 rs1012068 were identified as being associated with the development of HCV-induced hepatocellular carcinoma (HCC) in Japanese patients. The role of these variants on hepatic inflammation and fibrosis that are closely associated with HCC development is not known, nor are the biological mechanisms underlying their impact on the liver. Here, we demonstrate in 1689 patients with chronic hepatitis C (CHC) (1,501 with CHC and 188 with HCV-related HCC), that the MICA (T) allele, despite not being associated with HCC susceptibility, is associated with increased fibrosis stage (OR: 1.47, 95% CI: 1.05-2.06, p = 0.02) and fibrosis progression rate (hazards ratio: 1.41, 95% CI: 1.04-1.90, p = 0.02). The DEPDC5 variant was not associated with any of these phenotypes. MICA expression was down-regulated in advanced fibrosis stages. Further, (T) allele carriage was associated with lower MICA expression in liver and serum. Transforming growth factor-ß1 (TGF-ß1) expression suppresses MICA expression in hepatic stellate cells. Our findings suggest a novel mechanism linking susceptibility to advanced fibrosis and subsequently indirectly to HCC, to the level of MICA expression through TGF-ß1-dependent mechanisms.

7.
Aliment Pharmacol Ther ; 49(4): 437-447, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30637783

RESUMEN

BACKGROUND: Chemotherapy with gemcitabine and cisplatin is the current standard for patients with unresectable cholangiocarcinoma. Local photodynamic therapy has also demonstrated benefit in patients with extrahepatic cholangiocarcinoma. AIM: To evaluate the benefit of photodynamic therapy in combination with systemic chemotherapy in advanced extrahepatic cholangiocarcinoma. METHODS: Three hundred and fifty-three patients diagnosed with cholangiocarcinoma between 2004 and 2016 were treated at the University Hospital of Bonn, Germany. Of these, 96 suffering from unresectable extrahepatic cholangiocarcinoma were included. Patients were stratified according to treatment: combination photodynamic therapy and chemotherapy (36 patients), photodynamic therapy alone (34 patients), and chemotherapy alone (26 patients). RESULTS: Combined photodynamic therapy with chemotherapy resulted in significantly longer overall survival than chemotherapy alone (P = 0.022). Median survival was 20 months in the combination group (95% CI: 16.38-23.62), 15 months in the photodynamic alone group (95% CI: 10.02-19.98) and 10 months in the chemotherapy alone group (95% CI: 8.45-11.55). In multivariate analysis, combination therapy and photodynamic therapy alone (HR: 0.41, 95% CI: 0.22-0.77, P = 0.006), metal stenting, and radiofrequency ablation were independent predictors of longer survival. CONCLUSIONS: Combination photodynamic therapy and chemotherapy was well tolerated and resulted in significantly longer survival than chemotherapy alone. Application of photodynamic therapy significantly correlated with longer survival, demonstrating benefit in advanced cholangiocarcinoma. Thus, photodynamic therapy should be considered during therapeutic decision making in advanced cholangiocarcinoma.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de los Conductos Biliares/terapia , Colangiocarcinoma/terapia , Fotoquimioterapia/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de los Conductos Biliares/diagnóstico , Conductos Biliares Intrahepáticos/patología , Colangiocarcinoma/diagnóstico , Cisplatino/administración & dosificación , Terapia Combinada , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
8.
Zentralbl Chir ; 2018 Aug 01.
Artículo en Alemán | MEDLINE | ID: mdl-30068014

RESUMEN

INTRODUCTION: Prophylactic total gastrectomy is the treatment of choice in patients with germline mutation in the CDH1 gene and therefore high risk for hereditary diffuse gastric cancer (HDGC). Minimally invasive techniques have been established in recent years for treatment of gastric cancer. METHODS: We report findings with 12 patients with proven CDH1 mutation who underwent multidisciplinary treatment between 2013 and 3/2018 in our centre for hereditary tumour diseases, followed by prophylactic total gastrectomy in our department. Data were collected in a prospective hereditary tumour database. RESULTS: Open prophylactic total gastrectomy was performed in 5 patients (between 2013 and 2015) and minimally invasive prospective gastrectomy in 7 patients (between 2015 and 2018). The median age of all patients (7 women and 5 men) was 42 (range: 19 - 60) years. The mean operation time was 291 ± 72 minutes (open: 269 ± 70; minimally invasive: 307 ± 75). Perioperative 60-day mortality and anastomotic leakage rate were 0%. In 3 patients, postoperative complications occurred (according to the Clavien-Dindo classification: one each of grades II, IIIa and IVb, respectively), and therefore 25% morbidity. The average postoperative hospital stay was 14.5 ± 6.2 days (open: 16.2 ± 7.9; minimally invasive: 13.3 ± 5.0). In 10 of 12 patients (83%), foci of intramucosal signet ring cell carcinomas were found in the gastric specimen, in 9 patients with multifocal dissemination. There were no cases with advanced carcinomas (≥ pT1b) or lymph node metastases. CONCLUSION: Patients with suspected high risk for hereditary diffuse gastric cancer should be cared for in a multidisciplinary centre for hereditary tumour diseases. Laparoscopic total gastrectomy is a safe and feasible risk-reducing procedure for patients with CDH1 germline mutation. Therefore, in the absence of contraindications and with available surgical expertise, the minimally invasive operation should be the standard procedure for these patients.

9.
Zentralbl Chir ; 143(6): 577-585, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29996169

RESUMEN

INTRODUCTION: Pancreatic fluid collection (PFC) is a common complication of acute pancreatitis. Endoscopic ultrasound (EUS)-guided drainage, which is often followed by direct endoscopic necrosectomy (DEN), has become the primary approach to treat PFC, including pancreatic pseudocysts (PP) and walled-off necrosis (WON). We aimed to determine retrospectively the short- and long-term results of patients treated in our endoscopy unit and to identify parameters that are associated with treatment efficacy and outcome. METHODS: The data of 41 consecutive patients with post-pancreatitic PFC, who underwent endoscopic transmural intervention between 2014 and 2016, were analyzed retrospectively. After an initial EUS-guided puncture, one or more plastic stents were placed and DEN was performed if necrotic tissue remained. RESULTS: The mean diameter of the PFC was 74.0 ± 4.8 mm. Of the PFCs, 29.3% were classified as PP and 70.7% as WON. Altogether, 196 transmural endoscopic procedures were performed, including 73 endoscopic necrosectomies in a subgroup of 21 patients (20 WON, 1 PP). Initial technical success was achieved in 97.6% of patients and the short-term clinical success rate was 90.2%. The long-term clinical success rate was 82.9%, since four patients died from septic shock and/or multiple organ failure and three patients developed recurrent PFC some months after the initial discharge from endoscopic treatment. Procedural complications were registered in 9 patients during 10 of 196 endoscopic procedures (5.1%): bleeding (6), cardiorespiratory insufficiency (2), perforation with pneumoperitoneum (1), aspiration with respiratory insufficiency (1), and non-perforating superficial damage of the gastric wall (1). Neither the size of the PFC nor the initial value of C-reactive protein (CRP) or other biochemical markers were correlated with efficacy or outcome of treatment. Only the cumulative number of days with CRP > 50 mg/L significantly correlated with the number of follow-up endoscopic sessions and DEN. Fungal colonization of PFC correlated significantly (p < 0.05) with the risk of mortality (44% vs. 0%), need for intensive care treatment (66.7% vs. 25%), and sepsis (55.6% vs. 12.5%). CONCLUSIONS: We confirm that EUS-guided drainage followed by DEN in patients with solid necrotic material is an effective and relatively safe therapeutic approach. Prolonged elevation of CRP and fungal colonisation of the PFC are associated with a worse course of the disease.


Asunto(s)
Pancreatitis Crónica , Drenaje , Endosonografía , Humanos , Jugo Pancreático , Pancreatitis Crónica/diagnóstico por imagen , Estudios Retrospectivos , Stents , Resultado del Tratamiento
10.
Artículo en Inglés | MEDLINE | ID: mdl-29213343

RESUMEN

Background: Serrated or Hyperplastic Polyposis Syndrome (SPS, HPS) is a yet poorly defined colorectal cancer (CRC) predisposition characterised by the occurrence of multiple and/or large serrated polyps throughout the colon. A serrated polyp-CRC sequence (serrated pathway) of CRC formation has been postulated, however, to date only few molecular signatures of serrated neoplasia (BRAF, KRAS, RNF43 mutations, CpG Island Methylation, MSI) have been described in a subset of SPS patients and neither the etiology of the syndrome nor the distinct genetic alterations during tumorigenesis have been identified. Methods: To identify somatic point mutations in potential novel candidate genes of SPS-associated lesions and the involved pathways we performed exome sequencing of eleven early serrated polyps obtained from a 41 year-old female patient with clinically confirmed SPS. For data filtering and analysis, standard pipelines were used. Somatic mutations were identified by comparison with leukocyte DNA and were validated by Sanger sequencing. Results: The BRAF p.V600E or KRAS p.G12D mutation was identified in six polyps (~50%) and not found in polyps from the distal colon. In addition, we found seven unique rare somatic alterations of seven different genes in four serrated tumours, all of which are missense variants. The variant in ABI3BP and CATSPERB are predicted to be deleterious. No established cancer gene or candidate genes related to serrated tumorigenesis were affected. Conclusions: Somatic mutations seem to be rare events in early hyperplastic and serrated lesions of SPS patients. Neither frequently affected genes nor enrichment of specific pathways were observed. Thus, other alterations such as non-coding variants or epigenetic changes might be the major driving force of tumour progression in SPS.

12.
J Pathol ; 243(2): 242-254, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28727142

RESUMEN

Colorectal cancer (CRC) arising in Lynch syndrome (LS) comprises tumours with constitutional mutations in DNA mismatch repair genes. There is still a lack of whole-genome and transcriptome studies of LS-CRC to address questions about similarities and differences in mutation and gene expression characteristics between LS-CRC and sporadic CRC, about the molecular heterogeneity of LS-CRC, and about specific mechanisms of LS-CRC genesis linked to dysfunctional mismatch repair in LS colonic mucosa and the possible role of immune editing. Here, we provide a first molecular characterization of LS tumours and of matched tumour-distant reference colonic mucosa based on whole-genome DNA-sequencing and RNA-sequencing analyses. Our data support two subgroups of LS-CRCs, G1 and G2, whereby G1 tumours show a higher number of somatic mutations, a higher amount of microsatellite slippage, and a different mutation spectrum. The gene expression phenotypes support this difference. Reference mucosa of G1 shows a strong immune response associated with the expression of HLA and immune checkpoint genes and the invasion of CD4+ T cells. Such an immune response is not observed in LS tumours, G2 reference and normal (non-Lynch) mucosa, and sporadic CRC. We hypothesize that G1 tumours are edited for escape from a highly immunogenic microenvironment via loss of HLA presentation and T-cell exhaustion. In contrast, G2 tumours seem to develop in a less immunogenic microenvironment where tumour-promoting inflammation parallels tumourigenesis. Larger studies on non-neoplastic mucosa tissue of mutation carriers are required to better understand the early phases of emerging tumours. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Neoplasias Colorrectales/genética , Mutación/genética , Antígenos de Neoplasias/genética , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/inmunología , Expresión Génica/genética , Genes Relacionados con las Neoplasias/genética , Genoma Humano/genética , Humanos , Inmunidad Celular , Fenotipo , Recurrencia , Transcriptoma/genética , Escape del Tumor/genética , Escape del Tumor/inmunología
13.
Dig Dis Sci ; 62(9): 2558-2568, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28597106

RESUMEN

BACKGROUND AND AIMS: Absolute polymorphonuclear (PMN) counts in ascites define spontaneous bacterial peritonitis (SBP), a severe form of bacterial infection in liver cirrhosis. Bacterascites, another form of ascites infection, can progress to SBP or may resolve spontaneously but is not reflected by absolute PMN counts. We investigated whether the relative ascites PMN count (the absolute PMN count divided by the absolute leukocyte count) provides additional information to detect bacterascites or predict SBP. METHODS: Hospitalized patients with liver cirrhosis requiring paracentesis were stratified with respect to a diagnosis of bacterascites and SBP with a prospective follow-up for 1 year. Diagnostic power of relative PMN counts in ascites was evaluated by receiver operating characteristics curves. RESULTS: At inclusion, we observed 28/269 (10%) and 43/269 (16%) episodes of BA and SBP, respectively. Unlike absolute PMN counts, relative PMN counts in ascites were significantly elevated in bacterascites (p = 0.001). During follow-up, 16 and 30 further episodes of BA and SBP were detected, respectively. Relative PMN counts increased significantly once patients developed BA (p = 0.001). At a threshold of 0.20 for the relative PMN count, sensitivity, specificity, positive and negative predictive values for bacterascites which required antibiotic treatment were 83, 75, 26 and 98%, respectively (p < 0.001). Furthermore, a relative PMN count in ascites ≥0.13 and MELD score >17 was independent factors associated with occurrence of SBP during follow-up. CONCLUSION: The relative PMN count is a cheap immunological marker linked to bacterascites and future SBP, which may help to stratify patients according to their risk of infection.


Asunto(s)
Ascitis/patología , Infecciones Bacterianas/patología , Cirrosis Hepática/patología , Neutrófilos/patología , Peritonitis/patología , Anciano , Ascitis/epidemiología , Ascitis/inmunología , Líquido Ascítico/microbiología , Líquido Ascítico/patología , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/inmunología , Recuento de Células/métodos , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Cirrosis Hepática/epidemiología , Cirrosis Hepática/inmunología , Masculino , Persona de Mediana Edad , Neutrófilos/inmunología , Peritonitis/epidemiología , Peritonitis/inmunología , Estudios Prospectivos , Factores de Riesgo
14.
PLoS Pathog ; 13(5): e1006373, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28505204

RESUMEN

Innate lymphocyte cells (ILCs), a novel family of innate immune cells are considered to function as key orchestrators of immune defences at mucosal surfaces and to be crucial for maintaining an intact intestinal barrier. Accordingly, first data suggest depletion of ILCs to be involved in human immunodeficiency virus (HIV)-associated damage of the intestinal mucosa and subsequent microbial translocation. However, although ILCs are preferentially localized at mucosal surfaces, only little is known regarding distribution and function of ILCs in the human gastrointestinal tract. Here, we show that in HIV(-) individuals composition and functional capacity of intestinal ILCs is compartment-specific with group 1 ILCs representing the major fraction in the upper gastrointestinal (GI) tract, whereas ILC3 are the predominant population in ileum and colon, respectively. In addition, we present first data indicating that local cytokine concentrations, especially that of IL-7, might modulate composition of gut ILCs. Distribution of intestinal ILCs was significantly altered in HIV patients, who displayed decreased frequency of total ILCs in ileum and colon owing to reduced numbers of both CD127(+)ILC1 and ILC3. Of note, frequency of colonic ILC3 was inversely correlated with serum levels of I-FABP and sCD14, surrogate markers for loss of gut barrier integrity and microbial translocation, respectively. Both expression of the IL-7 receptor CD127 on ILCs as well as mucosal IL-7 mRNA levels were decreased in HIV(+) patients, especially in those parts of the GI tract with reduced ILC frequencies, suggesting that impaired IL-7 responses of ILCs might contribute to incomplete reconstitution of ILCs under effective anti-retroviral therapy. This is the first report comparing distribution and function of ILCs along the intestinal mucosa of the entire human gastrointestinal tract in HIV(+) and HIV(-) individuals.


Asunto(s)
Infecciones por VIH/inmunología , Intestinos/inmunología , Linfocitos/inmunología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Humanos , Inmunidad Innata , Interleucina-7/genética , Interleucina-7/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/virología , Intestinos/virología , Linfocitos/virología , Especificidad de Órganos
15.
PLoS One ; 12(4): e0174465, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28380039

RESUMEN

BACKGROUND: A relevant proportion of human immunodeficiency virus (HIV) infected patients is co-infected with the hepatitis C virus (HCV). HCV co-infection in HIV-positive patients is associated with faster progression of liver disease in comparison to HCV mono-infection. Natural killer (NK) cells critically modulate the natural course of HCV infection. Both HIV and HCV mono-infection are associated with alterations of the NK cell pool. However, little data is available concerning phenotype and function of NK cells in HIV/HCV co-infection. METHODS: A total of 34 HIV/HCV co-infected, 35 HIV and 39 HCV mono-infected patients and 43 healthy control persons were enrolled into this study. All HIV-positive patients were under effective antiretroviral therapy. NK cell phenotype, IFN-γ production and degranulation were studied by flow cytometry. RESULTS: NK cell frequency in HIV/HCV co-infection was significantly lower than in healthy individuals but did not differ from HIV and HCV mono-infection. HIV/HCV co-infection was associated with significantly decreased expression of the maturation/differentiation markers CD27/62L/127 on NK cells but increased expression of CD57 compared to healthy controls. Of note, expression also differed significantly from HCV mono-infection but was similar to HIV mono-infection, suggesting a pronounced impact of HIV on these alterations. Similar findings were made with regard to the NK cell receptors NKG2A/C and NKp30. More importantly, NK cells in co-infection displayed a highly impaired functional activity with significantly lower IFN-γ production and degranulation than in healthy donors as well as HIV and HCV mono-infection, suggesting a synergistic effect of both viruses. CONCLUSIONS: Our data indicate that HIV/HCV co-infection is associated with significant alterations of the NK cell pool, which might be involved in the rapid progression of liver disease in co-infected patients and which mainly reflect alterations observed in HIV mono-infection.


Asunto(s)
Coinfección/inmunología , Infecciones por VIH/complicaciones , Hepatitis C/complicaciones , Células Asesinas Naturales/fisiología , Adulto , Anciano , Estudios de Casos y Controles , Coinfección/virología , Estudios Transversales , Citometría de Flujo , Infecciones por VIH/inmunología , Hepatitis C/inmunología , Humanos , Interferón gamma/metabolismo , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Adulto Joven
16.
Nat Genet ; 49(5): 795-800, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28394349

RESUMEN

Genetic variation in the IFNL3-IFNL4 (interferon-λ3-interferon-λ4) region is associated with hepatic inflammation and fibrosis. Whether IFN-λ3 or IFN-λ4 protein drives this association is not known. We demonstrate that hepatic inflammation, fibrosis stage, fibrosis progression rate, hepatic infiltration of immune cells, IFN-λ3 expression, and serum sCD163 levels (a marker of activated macrophages) are greater in individuals with the IFNL3-IFNL4 risk haplotype that does not produce IFN-λ4, but produces IFN-λ3. No difference in these features was observed according to genotype at rs117648444, which encodes a substitution at position 70 of the IFN-λ4 protein and reduces IFN-λ4 activity, or between patients encoding functionally defective IFN-λ4 (IFN-λ4-Ser70) and those encoding fully active IFN-λ4-Pro70. The two proposed functional variants (rs368234815 and rs4803217) were not superior to the discovery SNP rs12979860 with respect to liver inflammation or fibrosis phenotype. IFN-λ3 rather than IFN-λ4 likely mediates IFNL3-IFNL4 haplotype-dependent hepatic inflammation and fibrosis.


Asunto(s)
Haplotipos , Inflamación/genética , Interleucinas/genética , Hígado/metabolismo , Fibrosis/genética , Fibrosis/metabolismo , Frecuencia de los Genes , Genotipo , Hepacivirus/fisiología , Hepatitis C/genética , Hepatitis C/virología , Humanos , Inflamación/metabolismo , Interferones , Interleucinas/metabolismo , Desequilibrio de Ligamiento , Hígado/patología , Modelos Logísticos , Análisis Multivariante , Polimorfismo de Nucleótido Simple , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
J Hepatol ; 66(5): 888-896, 2017 05.
Artículo en Albanés, Inglés | MEDLINE | ID: mdl-28040549

RESUMEN

BACKGROUND & AIMS: CD4+ regulatory T cells (Tregs) expand during chronic hepatitis C virus (HCV) infection, inhibit antiviral immunity and promote fibrosis. Direct-acting antiviral agents (DAA) have revolutionized HCV therapy. However, it is unclear if Tregs are normalized after DAA-induced HCV elimination. METHODS: We analyzed Tregs before (baseline), at end of therapy (EOT), 12 and 24weeks (SVR12, SVR24) and long-term (51±14weeks) after EOT in 26 genotype-1-infected patients who were successfully treated with sofosbuvir (SOF) plus interferon (IFN)/ribavirin (n=12) and IFN-free DAA regimens (SOF plus daclatasvir or simeprevir; n=14). Frequency, phenotype and suppressor function of peripheral Foxp3+ CD25+ CD4+ T cells were studied by multi-color flow cytometry and co-culture inhibition assays. RESULTS: Frequencies and activation status of Foxp3+ CD25+ CD4+ T cells remained elevated above those of normal controls in both treatment groups even long-term after HCV elimination. Co-culture assays indicated a dose-response relationship for functional inhibition of autologous CD4+ effector T cells and confirmed that activation of Tregs remained largely unchanged over the observation period. Unlike IFN-free regimens, SOF plus IFN/ribavirin induced a transiently increased frequency of Foxp3+ CD25+ CD4+ T cells at EOT (5.0% at baseline to 6.1% at EOT; p=0.001). These Foxp3+ CD25+ CD4+ T cells co-expressed the activation markers glycoprotein A repetitions predominant (GARP; p=0.012) and tumor necrosis factor receptor superfamily, member 4 (OX-40; p=0.001) but showed unchanged in vitro inhibitory activity. CONCLUSION: Although IFN-based DAA therapy induced transient expansion of activated Foxp3+ CD25+ CD4+ T cells, neither IFN-based nor IFN-free DAA regimens normalized frequencies and activation status of Tregs one year after viral elimination. Persistence of immunosuppressive Tregs may thus contribute to complications of liver disease even long-term after HCV cure. LAY SUMMARY: In chronic hepatitis C virus (HCV) infection, CD4+ regulatory T cells (Tregs) can reduce antiviral immune responses, promote liver fibrosis and may increase the risk for liver cancer, because they gradually expand during disease. Modern direct-acting antiviral agents (DAA) can "cure" hepatitis C in almost all treated patients. However, our study shows that DAA do not normalize the increased frequency and activation status of Tregs even long-term after HCV elimination. Tregs may persistently modulate functions of the immune system even after "cure" of hepatitis C.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Linfocitos T Reguladores/inmunología , Adulto , Anciano , Femenino , Factores de Transcripción Forkhead/análisis , Galectinas/sangre , Hepatitis C Crónica/inmunología , Humanos , Masculino , Persona de Mediana Edad
18.
Eur J Clin Invest ; 47(1): 44-52, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27861767

RESUMEN

BACKGROUND: Spontaneous bacterial peritonitis (SBP) can be life threatening in patients with liver cirrhosis. In contrast to community-acquired SBP, no standard treatment has been established for healthcare-related and nosocomial SBP. MATERIALS AND METHODS: We prospectively collected healthcare-related and nosocomial SBP cases from March 2012 till February 2016 at the Department of Internal Medicine I of the University of Bonn and analysed the prevalence of antibiotic resistance among the isolated bacteria. SBP was diagnosed according to international guidelines. Ciprofloxacin, ceftriaxone and meropenem were used as reference substance for resistance to quinolones, third-generation cephalosporins and carbapenems, respectively. RESULTS: Ninety-two SBP episodes in 86 patients were identified: 63 episodes (69%) were nosocomial. Escherichia coli, Klebsiella species, enterococci and streptococci were most frequently isolated. Frequencies of these microorganisms were comparable for healthcare-related and nosocomial SBP (14% vs. 11%, 14% vs. 8%, 14% vs. 5% and 10% vs. 6%, respectively). In general, antibiotic resistance was higher in isolates from nosocomial than from healthcare-related SBP (50% vs. 18% for quinolones, 30% vs. 11% for piperacillin-tazobactam; P > 0·05), but comparable concerning third-generation cephalosporins (30% vs. 33%). All microorganisms were sensitive to carbapenems apart from nosocomial infections with Enterococcus faecium (n = 3) and Candida albicans (n = 1) due to intrinsic resistance or lack of microbiological efficacy, respectively. No multidrug-resistant microorganisms were detected. Resistance to initial antibiotic treatment affected 30-day survival negatively (18% vs. 68%; P = 0·002). CONCLUSION: Resistance to initial antibiotic treatment was associated with increased mortality. With resistance to cephalosporins being frequent, piperacillin-tazobactam or carbapenems might be preferred as treatment of SBP.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Infecciones por Escherichia coli/microbiología , Infecciones por Klebsiella/microbiología , Peritonitis/microbiología , Infecciones Estreptocócicas/microbiología , Anciano , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/microbiología , Ceftriaxona , Ciprofloxacino , Infección Hospitalaria , Enterococcus , Infecciones por Escherichia coli/complicaciones , Femenino , Infecciones por Bacterias Grampositivas/complicaciones , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Infecciones por Klebsiella/complicaciones , Cirrosis Hepática/complicaciones , Masculino , Meropenem , Persona de Mediana Edad , Peritonitis/complicaciones , Estudios Prospectivos , Infecciones Estreptocócicas/complicaciones , Tienamicinas
19.
Endosc Int Open ; 4(12): E1305-E1310, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27995193

RESUMEN

Background and study aims: Hereditary diffuse gastric cancer (HGGC), an autosomal dominant tumor-syndrome, accounts for 1 % to 3 % of gastric cancers worldwide. Presumably 30 % to 40 % of all patients fulfilling the clinical guidelines for HDGC are carriers of a pathogenic mutation in the CDH1 gene. Patients often show multiple foci of signet ring cell carcinoma at early age and are advised to undergo prophylactic total gastrectomy (PTG). Our aim was to improve the endoscopic detection of HDGC by using an enhanced endoscopic protocol. Patient and methods: Patients with a proven CDH1 germline mutation identified in our institute were prospectively included. Patients were advised to undergo PTG and offered a baseline endoscopic examination prior surgery. Examination was performed by using high-resolution white-light endoscopy and pan-gastric chromoendoscopy with indigo carmine as dye combined with targeted and multiple random biopsies assessed by an expert histopathologist. Postoperative histopathology was compared with results from endoscopic biopsies. Results: Between September 2012 and November 2014 8 patients with a proven CDH1 germline mutation were included. We conducted 44 targeted (6.3/patient) and 225 random (32.1/patient) biopsies in 7 patients. We detected 1 gastric cancer by random biopsy (14 %). All other examinations showed no signs of cancer. Histopathology of gastrectomy specimen revealed multiple foci of gastric carcinoma in 6 patients (86 %) with a total number of 27 cancer foci. Conclusions: Examination with targeted and random biopsies combined with chromoendoscopy is not able to detect small foci of gastric cancer in CDH1 mutation carriers. Therefore PTG is advocated in these patients.

20.
PLoS One ; 11(9): e0162068, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27583440

RESUMEN

BACKGROUND: Immuno-genetic studies suggest a functional link between NK cells and λ-IFNs. We recently showed that NK cells are negative for the IFN-λ receptor IFN-λR1 and do not respond to IFN-λ, suggesting a rather indirect association between IL-28B genotype and NK cell activity. METHODS: A total of 75 HCV(+) patients and 67 healthy controls were enrolled into this study. IL-28B (rs12979860) and IFNL-4 (rs368234815) genotypes were determined by rtPCR. Total PBMC, monocytes, and NK cells were stimulated with IL-29, the TLR-7/8 agonist R848, or a combination of both. NK cell IFN-γ response was analysed by FACS. IL-12 and IL-18 secretion of monocytes was studied by ELISA. In blocking experiments anti-IL-12/anti-IL-18 were used. RESULTS: Following stimulation of total PBMCs with R848 we found NK cell IFN- γ responses to vary with the IL-28B genotype, with carriers of a T/T genotype displaying the lowest frequency of IFN-γ(+)NK cells. When isolated NK cells were studied no such associations were observed, indicating an indirect association between IL-28B genotype and NK cell activity. Accordingly, we found R848-stimulated monocytes of patients with a T/T genotype to be significantly less effective in triggering NK cell IFN- γ production than monocytes from carriers of a non-T/T genotype. In line with these findings we observed monocytes from T/T patients to secrete significantly lower concentrations of IL-12 than monocytes from non-T/T individuals. CONCLUSIONS: Our data indicate that monocytes from carriers of an IL-28B T/T genotype display a reduced ability to stimulate NK cell activity and, thus, provide a link between IL-28B genotype and NK functions.


Asunto(s)
Variación Genética , Hepatitis C/genética , Hepatitis C/inmunología , Interleucinas/genética , Células Asesinas Naturales/inmunología , Activación de Linfocitos/genética , Monocitos/citología , Femenino , Genotipo , Hepatitis C/metabolismo , Humanos , Interferones , Interleucina-12/biosíntesis , Células Asesinas Naturales/citología , Masculino , Persona de Mediana Edad , Monocitos/metabolismo
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