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1.
Eur J Immunol ; 53(2): e2249940, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36250419

RESUMO

Primary and recurrent cytomegalovirus (CMV) infections frequently cause CMV colitis in immunocompromised as well as inflammatory bowel disease (IBD) patients. Additionally, colitis occasionally occurs upon primary CMV infection in patients who are apparently immunocompetent. In both cases, the underlying pathophysiologic mechanisms are largely elusive - in part due to the lack of adequate access to specimens. We employed the mouse cytomegalovirus (MCMV) model to assess the association between CMV and colitis. During acute primary MCMV infection of immunocompetent mice, the gut microbial composition was affected as manifested by an altered ratio of the Firmicutes to Bacteroidetes phyla. Interestingly, these microbial changes coincided with high-titer MCMV replication in the colon, crypt hyperplasia, increased colonic pro-inflammatory cytokine levels, and a transient increase in the expression of the antimicrobial protein Regenerating islet-derived protein 3 gamma (Reg3γ). Further analyses revealed that murine and human intestinal epithelial cell lines, as well as primary intestinal crypt cells and organoids represent direct targets of CMV infection causing increased cell death. Accordingly, in vivo MCMV infection disrupted the intestinal epithelial barrier and increased apoptosis of intestinal epithelial cells. In summary, our data show that CMV transiently induces colitis in immunocompetent hosts by altering the intestinal homeostasis.


Assuntos
Colite , Infecções por Citomegalovirus , Microbioma Gastrointestinal , Muromegalovirus , Humanos , Animais , Camundongos , Citomegalovirus , Células Epiteliais/metabolismo
2.
Liver Int ; 44(1): 125-138, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37872645

RESUMO

OBJECTIVE: Progressive hepatic fibrosis can be considered the final stage of chronic liver disease. Hepatic stellate cells (HSC) play a central role in liver fibrogenesis. Thyroid hormones (TH, e.g. thyroxine; T4 and triiodothyronine; T3) significantly affect development, growth, cell differentiation and metabolism through activation of TH receptor α and/or ß (TRα/ß). Here, we evaluated the influence of TH in hepatic fibrogenesis. DESIGN: Human liver tissue was obtained from explanted livers following transplantation. TRα-deficient (TRα-KO) and wild-type (WT) mice were fed a control or a profibrogenic methionine-choline deficient (MCD) diet. Liver tissue was assessed by qRT-PCR for fibrogenic gene expression. In vitro, HSC were treated with TGFß in the presence or absence of T3. HSC with stable TRα knockdown and TRα deficient mouse embryonic fibroblasts (MEF) were used to determine receptor-specific function. Activation of HSC and MEF was assessed using the wound healing assay, Western blotting, and qRT-PCR. RESULTS: TRα and TRß expression is downregulated in the liver during hepatic fibrogenesis in humans and mice. TRα represents the dominant isoform in HSC. In vitro, T3 blunted TGFß-induced expression of fibrogenic genes in HSC and abrogated wound healing by modulating TGFß signalling, which depended on TRα presence. In vivo, TRα-KO enhanced MCD diet-induced liver fibrogenesis. CONCLUSION: These observations indicate that TH action in non-parenchymal cells is highly relevant. The interaction of TRα with TH regulates the phenotype of HSC via the TGFß signalling pathway. Thus, the TH-TR axis may be a valuable target for future therapy of liver fibrosis.


Assuntos
Fibroblastos , Células Estreladas do Fígado , Animais , Camundongos , Humanos , Células Estreladas do Fígado/metabolismo , Hormônios Tireóideos/metabolismo , Hormônios Tireóideos/farmacologia , Receptores alfa dos Hormônios Tireóideos/genética , Receptores alfa dos Hormônios Tireóideos/metabolismo , Fator de Crescimento Transformador beta
3.
J Sleep Res ; : e14178, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38385644

RESUMO

Oxidative stress in patients suffering from obstructive sleep apnea syndrome (OSAS) is associated with a low-grade systemic inflammation, immune disturbance, and increased invasion of monocytes into the endothelium. Besides continuous positive airway pressure (PAP), hypoglossal nerve stimulation (HNS) has become a promising treatment option for patients with OSAS. We aimed to analyse the influence of HNS therapy on the cellular characteristics relevant for adhesion and immune regulation of circulating CD14/CD16 monocyte subsets. Whole blood flow cytometric measurements were performed to analyse the expression levels of different adhesion molecules and checkpoint molecule PD-L1 (programmed death-ligand 1) in connection with pro-inflammatory plasma cytokine IL-8 and the clinical values of BMI (body mass index), AHI (apnea-hypopnea index), ODI (oxygen desaturation index), and ESS (Epworth sleepiness scale) upon HNS treatment. Hypoglossal nerve stimulation treatment significantly improved the expression of adhesion molecule CD162 (P-selectin receptor) on non-classical monocytes and significantly downregulated the expression of PD-L1 on all three monocyte subsets. We conclude that the holistic improvement of different parameters such as the oxygenation of the peripheral blood, a reduced systemic inflammation, and the individual sleeping situation upon HNS respiratory support, leads to an improved immunologic situation.

4.
Nature ; 561(7721): 63-69, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30158707

RESUMO

Glutamine synthetase, encoded by the gene GLUL, is an enzyme that converts glutamate and ammonia to glutamine. It is expressed by endothelial cells, but surprisingly shows negligible glutamine-synthesizing activity in these cells at physiological glutamine levels. Here we show in mice that genetic deletion of Glul in endothelial cells impairs vessel sprouting during vascular development, whereas pharmacological blockade of glutamine synthetase suppresses angiogenesis in ocular and inflammatory skin disease while only minimally affecting healthy adult quiescent endothelial cells. This relies on the inhibition of endothelial cell migration but not proliferation. Mechanistically we show that in human umbilical vein endothelial cells GLUL knockdown reduces membrane localization and activation of the GTPase RHOJ while activating other Rho GTPases and Rho kinase, thereby inducing actin stress fibres and impeding endothelial cell motility. Inhibition of Rho kinase rescues the defect in endothelial cell migration that is induced by GLUL knockdown. Notably, glutamine synthetase palmitoylates itself and interacts with RHOJ to sustain RHOJ palmitoylation, membrane localization and activation. These findings reveal that, in addition to the known formation of glutamine, the enzyme glutamine synthetase shows unknown activity in endothelial cell migration during pathological angiogenesis through RHOJ palmitoylation.


Assuntos
Células Endoteliais/enzimologia , Células Endoteliais/patologia , Glutamato-Amônia Ligase/metabolismo , Glutamina/biossíntese , Neovascularização Patológica , Actinas/metabolismo , Animais , Movimento Celular , Células Endoteliais/metabolismo , Feminino , Glutamato-Amônia Ligase/deficiência , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/fisiologia , Células HEK293 , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Lipoilação , Camundongos , Ácido Palmítico/metabolismo , Processamento de Proteína Pós-Traducional , Fibras de Estresse/metabolismo , Proteínas rho de Ligação ao GTP/química , Proteínas rho de Ligação ao GTP/metabolismo , Quinases Associadas a rho/metabolismo
5.
Gesundheitswesen ; 2024 Jun 28.
Artigo em Alemão | MEDLINE | ID: mdl-38942033

RESUMO

AIM: In 2003, a certification program was introduced by the German Cancer Society in Germany to ensure high standards of oncological care. The present study investigated whether there were differences in the concordance to guideline-based recommendations between centers certified by the German Cancer Society and medical facilities without such certification. In this context, quality indicators derived from clinical guidelines were evaluated. METHODS: The database of the cancer registry of Rhineland-Palatinate, Germany was used to calculate fulfilment of target values for 14 quality indicators. Analysis of quality indicators followed specifications given in treatment S3-guidelines for breast, colorectal and lung cancer. Analyses were done by R and SAS. RESULTS: All 14 quality indicators showed that concordance with guideline-based recommendations was higher in certified centers compared to uncertified medical facilities; 13 of these differences were statistically significant. CONCLUSION: Higher quality of oncological treatment in certified centers has widely been discussed in the WiZen study. The results of our study support this assumption with respect to concordance with quality indicators.

6.
Development ; 147(1)2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31908317

RESUMO

Zebrafish display widespread and pronounced adult neurogenesis, which is fundamental for their regeneration capability after central nervous system injury. However, the cellular identity and the biological properties of adult newborn neurons are elusive for most brain areas. Here, we have used short-term lineage tracing of radial glia progeny to prospectively isolate newborn neurons from the her4.1+ radial glia lineage in the homeostatic adult forebrain. Transcriptome analysis of radial glia, newborn neurons and mature neurons using single cell sequencing identified distinct transcriptional profiles, including novel markers for each population. Specifically, we detected two separate newborn neuron types, which showed diversity of cell fate commitment and location. Further analyses showed that these cell types are homologous to neurogenic cells in the mammalian brain, identified neurogenic commitment in proliferating radial glia and indicated that glutamatergic projection neurons are generated in the adult zebrafish telencephalon. Thus, we prospectively isolated adult newborn neurons from the adult zebrafish forebrain, identified markers for newborn and mature neurons in the adult brain, and revealed intrinsic heterogeneity among adult newborn neurons and their homology with mammalian adult neurogenic cell types.


Assuntos
Encéfalo/citologia , Linhagem da Célula , Células Ependimogliais/citologia , Neurogênese , Neurônios/citologia , Peixe-Zebra/anatomia & histologia , Animais , Animais Geneticamente Modificados , Animais Recém-Nascidos/anatomia & histologia , Diencéfalo/citologia , Perfilação da Expressão Gênica , Camundongos , Análise de Sequência de RNA , Análise de Célula Única , Telencéfalo/citologia , Peixe-Zebra/crescimento & desenvolvimento
7.
Development ; 147(24)2020 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-33158923

RESUMO

Spinal cord injury (SCI) results in loss of neurons, oligodendrocytes and myelin sheaths, all of which are not efficiently restored. The scarcity of oligodendrocytes in the lesion site impairs re-myelination of spared fibres, which leaves axons denuded, impedes signal transduction and contributes to permanent functional deficits. In contrast to mammals, zebrafish can functionally regenerate the spinal cord. Yet, little is known about oligodendroglial lineage biology and re-myelination capacity after SCI in a regeneration-permissive context. Here, we report that, in adult zebrafish, SCI results in axonal, oligodendrocyte and myelin sheath loss. We find that OPCs, the oligodendrocyte progenitor cells, survive the injury, enter a reactive state, proliferate and differentiate into oligodendrocytes. Concomitantly, the oligodendrocyte population is re-established to pre-injury levels within 2 weeks. Transcriptional profiling revealed that reactive OPCs upregulate the expression of several myelination-related genes. Interestingly, global reduction of axonal tracts and partial re-myelination, relative to pre-injury levels, persist at later stages of regeneration, yet are sufficient for functional recovery. Taken together, these findings imply that, in the zebrafish spinal cord, OPCs replace lost oligodendrocytes and, thus, re-establish myelination during regeneration.


Assuntos
Células Precursoras de Oligodendrócitos/citologia , Remielinização/genética , Traumatismos da Medula Espinal/genética , Medula Espinal/crescimento & desenvolvimento , Animais , Modelos Animais de Doenças , Humanos , Células Precursoras de Oligodendrócitos/transplante , Oligodendroglia/transplante , Regeneração/genética , Medula Espinal/transplante , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/terapia , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento
8.
Liver Int ; 43(4): 896-905, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36440606

RESUMO

BACKGROUND AND AIMS: Given the early response of neutrophil granulocytes to infections, detection of pathological neutrophil migration might help in predicting adverse events in patients with liver cirrhosis. METHODS: Migration of blood neutrophils in hospitalized patients with cirrhosis was characterized by a novel standardized migration assay. Pathological neutrophil migration patterns were associated with a composite endpoint of ACLF, sepsis or death within 7 or 30 days. RESULTS: Overall, 125 patients were included, of whom 11 (8.8%) had compensated cirrhosis, 84 (67.2%) had acute decompensation (AD) and 30 (24%) had acute-on-chronic liver failure (ACLF). The migration response of neutrophils from patients with AD or ACLF to stimulation with the chemotactic formylpeptide f-Met-Leu-Phe (fMLP) was significantly impaired, while the response to chemokine (C-X-C motif)-ligand 8 (CXCL8) was affected less pronouncedly. In contrast, no relevant differences in response to CXCL1 were observed. Of note, neutrophils of a number of patients with AD and ACLF were largely immotile at resting and stimulated conditions. Patients with non-migrating neutrophils at unstimulated conditions were at high risk to develop the composite endpoint of ACLF, sepsis or death. Moreover, expression of chemokine receptors CXCR1 and CXCR2 was significantly decreased in patients with ACLF. Interestingly, the expression of chemokine receptors did not correlate with neutrophil migration patterns, but-based on the increased expression of the cell surface markers CD66b and CD177-neutrophils of patients with AD and ACLF were strongly pre-activated. CONCLUSION: Pathological neutrophil migration in patients with cirrhosis indicates a high risk of developing adverse outcomes.


Assuntos
Insuficiência Hepática Crônica Agudizada , Sepse , Humanos , Neutrófilos , Cirrose Hepática/complicações , Fibrose , Receptores de Quimiocinas , Sepse/complicações , Prognóstico
9.
Liver Int ; 43(11): 2503-2512, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37602977

RESUMO

BACKGROUND AND AIMS: Data on number of patients with cirrhosis in Germany are limited. We therefore aimed to estimate prevalence, comorbidities, mortality, utilization of healthcare resources and costs of patients with cirrhosis and incidence of decompensation of cirrhosis in Germany. METHODS: This longitudinal observational study was based on an anonymized representative claims database including 4.9 million persons insured by a statutory health insurance (SHI) between 2015-2020. Patients with decompensated and compensated cirrhosis were selected via diagnostic ICD codes and followed for 2 years. RESULTS: Prevalence of cirrhosis in 2015 was 250/100 000, resulting in 201 747 (95% CI: 197 540-206 040) patients extrapolated to the German population. Out of all patients with compensated cirrhosis in 2015 who did not deceased, 16.0% developed a decompensation within 3 years. Overall, 978 patients (Ø-age: 68 years; 60% male) were included in the decompensated, and 5135 patients (Ø-age: 66 years; 59% male) in the compensated cirrhosis cohort. Patients with decompensated cirrhosis had a higher burden of comorbidities (Charlson Comorbidity Index 7.3 vs. 4.4) and 3 times higher costs per quarter (7172 € vs. 2213 €) than patients with compensated cirrhosis. 1-year mortality after decompensation was 51% compared to 8% in compensated cirrhosis. Of note, only few patients with decompensated cirrhosis received a liver transplantation or transjugular intrahepatic portosystemic shunts (TIPS) (1% and 5%). CONCLUSION: Patients with cirrhosis have a high healthcare burden in especially decompensated stage. Accordingly, 1-year mortality of decompensated cirrhosis in Germany is high. Despite high health resource utilization, only few patients have access to liver transplantation or TIPS.


Assuntos
Transplante de Fígado , Humanos , Masculino , Idoso , Feminino , Cirrose Hepática/epidemiologia , Cirrose Hepática/cirurgia , Comorbidade , Atenção à Saúde , Alemanha/epidemiologia , Estudos Retrospectivos
10.
Liver Int ; 43(9): 2002-2016, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37312627

RESUMO

BACKGROUND AND AIMS: Hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC) development and progression. The aim of this study was to mechanistically investigate the involvement of Hippo signalling in HBV surface antigen (HBsAg)-dependent neoplastic transformation. METHODS: Liver tissue and hepatocytes from HBsAg-transgenic mice were examined for the Hippo cascade and proliferative events. Functional experiments in mouse hepatoma cells included knockdown, overexpression, luciferase reporter assays and chromatin immunoprecipitation. Results were validated in HBV-related HCC biopsies. RESULTS: Hepatic expression signatures in HBsAg-transgenic mice correlated with YAP responses, cell cycle control, DNA damage and spindle events. Polyploidy and aneuploidy occurred in HBsAg-transgenic hepatocytes. Suppression and inactivation of MST1/2 led to the loss of YAP phosphorylation and the induction of BMI1 expression in vivo and in vitro. Increased BMI1 directly mediated cell proliferation associated with decreased level of p16INK4a , p19ARF , p53 and Caspase 3 as well as increased Cyclin D1 and γ-H2AX expression. Chromatin immunoprecipitation and the analysis of mutated binding sites in dual-luciferase reporter assays confirmed that the YAP/TEAD4 transcription factor complex bound and activated the Bmi1 promoter. In chronic hepatitis B patients, paired liver biopsies of non-tumour and tumour tissue indicated a correlation between YAP expression and the abundance of BMI1. In a proof-of-concept, treatment of HBsAg-transgenic mice with YAP inhibitor verteporfin directly suppressed the BMI1-related cell cycle. CONCLUSION: HBV-associated proliferative HCC might be related to the HBsAg-YAP-BMI1 axis and offer a potential target for the development of new therapeutic approaches.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Animais , Camundongos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Hepatite B/complicações , Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Camundongos Transgênicos
11.
J Immunol ; 206(1): 51-58, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33268482

RESUMO

Obstructive sleep apnea syndrome (OSAS) represents a substantial disease of recurrent sleep fragmentation, leading to intermittent hypoxia and subsequent diseases such as cardiovascular, metabolic, or cognitive dysfunctions. In addition, OSAS is considered as low-grade systemic inflammation, which is associated with a higher incidence of cancer, severity of infections, and an overall immune dysregulation. This research project aims to comprehensively investigate the interplay of wholesome sleep and the immune functions of circulating monocytes and T cells in OSAS patients, which are known to be affected by oxidative stress. We studied the distribution of the CD14/CD16 characterized monocyte subsets in peripheral blood as well as their PD-L1 expression and complex formation with T cells. Furthermore, a detailed analysis of T cell subsets with regard to their PD-1 and PD-L1 expression was performed. Data revealed a decrease of classical monocytes accompanied by an increase of both CD16+ monocyte subsets in OSAS patients that was positively correlated with the body mass index. OSAS patients revealed an increased PD-1 and PD-L1 expression in T cells and monocytes, respectively, which was linked to the severity of monocyte subset alterations. The complex formation of monocytes and T cells was also elevated in OSAS patients, which indicates a deregulated PD-1/PD-L1 cross-talk between these cells. Our data show for the first time, to our knowledge, massive alterations of peripheral monocyte subsets in response to OSAS and its accompanying phenomena.


Assuntos
Antígeno B7-H1/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Monócitos/imunologia , Receptor de Morte Celular Programada 1/metabolismo , Apneia Obstrutiva do Sono/imunologia , Adulto , Movimento Celular , Células Cultivadas , Feminino , Humanos , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Receptor Cross-Talk , Receptores de IgG/metabolismo
12.
Langenbecks Arch Surg ; 408(1): 191, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37171640

RESUMO

PURPOSE: The objective of this work was to uncover inequalities in access to liver transplantation in Bavaria, Germany. METHODS: For this purpose, the annual transplantation rate per 1 million inhabitants for the respective districts was determined from the aggregated postal codes of the place of residence of transplanted patients. The variables examined were proximity and travel time to the nearest transplant center, as well as the care category of the regional hospital. In addition, we assessed whether the head of gastroenterology at the regional hospital through which liver transplant candidates are referred was trained at a liver transplant center. RESULTS: We could not demonstrate a direct relationship between proximity or travel time to the nearest transplant center and access to liver transplantation. Multivariate regression analysis shows that liver transplant training (p < 0.0001) of the chief physician (gastroenterologist) of the regional hospital was the most decisive independent factor for access to liver transplantation within a district. CONCLUSION: We show that the transplant training experience of the head of gastroenterology at a regional hospital is an independent factor for the regional transplantation rate. Therefore, it appears important to maintain some liver transplant expertise outside the transplant centers in order to properly identify and assign potential transplant candidates for transplantation.


Assuntos
Transplante de Fígado , Médicos , Humanos , Alemanha
13.
Z Gastroenterol ; 61(9): 1225-1234, 2023 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-36377140

RESUMO

Advanced chronic liver disease is accompanied with relevant changes in the corpuscular and plasmatic coagulation system. Due to thrombocytopenia that is regularly observed in these patients, platelet transfusions are often performed prior invasive procedures to prevent possible bleeding complications. However, platelet transfusions are associated with clinically significant adverse events and economically relevant health care costs. Thus, avoiding unnecessary platelet transfusions remains pivotal in daily clinical practice. The first step is to carefully check if increasing platelet counts prior to a planned invasive procedure is really necessary. Nowadays, two well-tolerated thrombopoetin-receptor agonists (TPO-RAs), Avatrombopaq and Lusutrombopaq, to treat thrombocytopenia preemptively before an invasive procedure in patients with liver cirrhosis are available. This review provides a guide for clinician when to increase platelet counts prior an invasive procedure in patients with liver cirrhosis and helps to identify situations in which the use of TPO-RA may be reasonable.


Assuntos
Hepatopatias , Trombocitopenia , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Trombocitopenia/induzido quimicamente , Trombocitopenia/complicações , Contagem de Plaquetas , Hepatopatias/complicações , Transfusão de Plaquetas/efeitos adversos
14.
Small ; 18(31): e2201167, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35712760

RESUMO

Ultrasmall gold nanoparticles (2 nm) easily penetrate the membranes of intestinal murine epithelial cells (MODE-K) and colorectal cancer cells (CT-26). They are also taken up by 3D spheroids (400 µm) of these cell types and primary gut organoids (500 µm). In contrast, dissolved dyes are not taken up by any of these cells or 3D structures. The distribution of fluorescent ultrasmall gold nanoparticles inside cells, spheroids, and gut organoids is examined by confocal laser scanning microscopy. Nanoparticles conjugated with the cytostatic drug doxorubicin and a fluorescent dye exhibit significantly greater cytotoxicity toward CT-26 tumor spheroids than equally concentrated dissolved doxorubicin, probably because they enter the interior of a spheroid much more easily than dissolved doxorubicin. Comprehensive analyses show that the cellular uptake of ultrasmall gold nanoparticles occurs by different endocytosis pathways.


Assuntos
Nanopartículas Metálicas , Neoplasias , Animais , Doxorrubicina/química , Doxorrubicina/farmacologia , Ouro , Humanos , Camundongos , Esferoides Celulares
15.
EMBO Rep ; 21(12): e50612, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33140917

RESUMO

The thyroid gland regulates growth and metabolism via production of thyroid hormone in follicles composed of thyrocytes. So far, thyrocytes have been assumed to be a homogenous population. To uncover heterogeneity in the thyrocyte population and molecularly characterize the non-thyrocyte cells surrounding the follicle, we developed a single-cell transcriptome atlas of the region containing the zebrafish thyroid gland. The 6249-cell atlas includes profiles of thyrocytes, blood vessels, lymphatic vessels, immune cells, and fibroblasts. Further, the thyrocytes show expression heterogeneity, including bimodal expression of the transcription factor pax2a. To validate thyrocyte heterogeneity, we generated a CRISPR/Cas9-based pax2a knock-in line that monitors pax2a expression in the thyrocytes. A population of pax2a-low mature thyrocytes interspersed in individual follicles can be distinguished. We corroborate heterogeneity within the thyrocyte population using RNA sequencing of pax2a-high and pax2a-low thyrocytes, which demonstrates 20% differential expression in transcriptome between the two subpopulations. Our results identify and validate transcriptional differences within the presumed homogenous thyrocyte population.


Assuntos
Células Epiteliais da Tireoide , Glândula Tireoide , Animais , Perfilação da Expressão Gênica , Transcriptoma , Peixe-Zebra/genética
16.
Future Oncol ; 18(12): 1423-1435, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35081747

RESUMO

The combination of the anti-PD-L1 antibody atezolizumab and the anti-VEGF bevacizumab is the first approved immunotherapeutic regimen for first-line therapy in patients with unresectable hepatocellular carcinoma (HCC), currently approved in more than 80 countries. The efficacy and tolerability of this regimen suggest that the use of atezolizumab + bevacizumab could be extended to the treatment of patients with intermediate-stage HCC in combination with transarterial chemoembolization (TACE). The authors describe the rationale and design of the DEMAND study. This investigator-initiated, multicenter, randomized phase II study is the first trial to evaluate the safety and efficacy of atezolizumab + bevacizumab prior to or in combination with TACE in patients with intermediate-stage HCC. The primary end point is the 24-month survival rate; secondary end points include objective response rate, progression-free survival, safety and quality of life. Clinical Trial Registration: NCT04224636 (ClinicalTrials.gov).


Assuntos
Anticorpos Monoclonais Humanizados , Bevacizumab , Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Bevacizumab/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Quimioembolização Terapêutica/métodos , Ensaios Clínicos Fase II como Assunto , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Estudos Multicêntricos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
17.
Euro Surveill ; 27(43)2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36305336

RESUMO

BackgroundTracking person-to-person SARS-CoV-2 transmission in the population is important to understand the epidemiology of community transmission and may contribute to the containment of SARS-CoV-2. Neither contact tracing nor genomic surveillance alone, however, are typically sufficient to achieve this objective.AimWe demonstrate the successful application of the integrated genomic surveillance (IGS) system of the German city of Düsseldorf for tracing SARS-CoV-2 transmission chains in the population as well as detecting and investigating travel-associated SARS-CoV-2 infection clusters.MethodsGenomic surveillance, phylogenetic analysis, and structured case interviews were integrated to elucidate two genetically defined clusters of SARS-CoV-2 isolates detected by IGS in Düsseldorf in July 2021.ResultsCluster 1 (n = 67 Düsseldorf cases) and Cluster 2 (n = 36) were detected in a surveillance dataset of 518 high-quality SARS-CoV-2 genomes from Düsseldorf (53% of total cases, sampled mid-June to July 2021). Cluster 1 could be traced back to a complex pattern of transmission in nightlife venues following a putative importation by a SARS-CoV-2-infected return traveller (IP) in late June; 28 SARS-CoV-2 cases could be epidemiologically directly linked to IP. Supported by viral genome data from Spain, Cluster 2 was shown to represent multiple independent introduction events of a viral strain circulating in Catalonia and other European countries, followed by diffuse community transmission in Düsseldorf.ConclusionIGS enabled high-resolution tracing of SARS-CoV-2 transmission in an internationally connected city during community transmission and provided infection chain-level evidence of the downstream propagation of travel-imported SARS-CoV-2 cases.


Assuntos
COVID-19 , Doenças Transmissíveis Importadas , Humanos , SARS-CoV-2/genética , Viagem , Doenças Transmissíveis Importadas/epidemiologia , COVID-19/epidemiologia , Filogenia , Busca de Comunicante , Alemanha/epidemiologia , Genômica
18.
J Biol Chem ; 295(40): 13862-13874, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-32747444

RESUMO

Inhibitors against the NS3-4A protease of hepatitis C virus (HCV) have proven to be useful drugs in the treatment of HCV infection. Although variants have been identified with mutations that confer resistance to these inhibitors, the mutations do not restore replicative fitness and no secondary mutations that rescue fitness have been found. To gain insight into the molecular mechanisms underlying the lack of fitness compensation, we screened known resistance mutations in infectious HCV cell culture with different genomic backgrounds. We observed that the Q41R mutation of NS3-4A efficiently rescues the replicative fitness in cell culture for virus variants containing mutations at NS3-Asp168 To understand how the Q41R mutation rescues activity, we performed protease activity assays complemented by molecular dynamics simulations, which showed that protease-peptide interactions far outside the targeted peptide cleavage sites mediate substrate recognition by NS3-4A and support protease cleavage kinetics. These interactions shed new light on the mechanisms by which NS3-4A cleaves its substrates, viral polyproteins and a prime cellular antiviral adaptor protein, the mitochondrial antiviral signaling protein MAVS. Peptide binding is mediated by an extended hydrogen-bond network in NS3-4A that was effectively optimized for protease-MAVS binding in Asp168 variants with rescued replicative fitness from NS3-Q41R. In the protease harboring NS3-Q41R, the N-terminal cleavage products of MAVS retained high affinity to the active site, rendering the protease susceptible for potential product inhibition. Our findings reveal delicately balanced protease-peptide interactions in viral replication and immune escape that likely restrict the protease adaptive capability and narrow the virus evolutionary space.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Hepacivirus/fisiologia , Simulação de Dinâmica Molecular , Inibidores de Proteases/farmacologia , Replicação Viral/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Substituição de Aminoácidos , Linhagem Celular Tumoral , Humanos , Mutação de Sentido Incorreto , Serina Proteases/química , Serina Proteases/genética , Serina Proteases/metabolismo , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Replicação Viral/genética
19.
J Hepatol ; 75(6): 1346-1354, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34364917

RESUMO

BACKGROUND & AIMS: Based on positive results from small single center studies, granulocyte-colony stimulating factor (G-CSF) is being widely used for the treatment of patients with acute-on-chronic liver failure (ACLF). Herein, we aimed to evaluate the safety and efficacy of G-CSF in patients with ACLF. METHODS: In this multicenter, prospective, controlled, open-label phase II study, 176 patients with ACLF (EASL-CLIF criteria) were randomized to receive G-CSF (5 µg/kg daily for the first 5 days and every third day thereafter until day 26) plus standard medical therapy (SMT) (n = 88) or SMT alone. The primary efficacy endpoint was 90-day transplant-free survival analyzed by Cox regression modeling. The key secondary endpoints were overall and transplant-free survival after 360 days, the development of ACLF-related complications, and the course of liver function scores during the entire observation period. RESULTS: Patients treated with G-CSF had a 90-day transplant-free survival rate of 34.1% compared to 37.5% in the SMT group (hazard ratio [HR] 1.05; 95% CI 0.711-1.551; p = 0.805). Transplant-free and overall survival at 360 days did not differ between the 2 arms (HR 0.998; 95% CI 0.697-1.430; p = 0.992 and HR 1.058; 95% CI 0.727-1.548; p = 0.768, respectively). G-CSF did not improve liver function scores, the occurrence of infections, or survival in subgroups of patients without infections, with alcohol-related ACLF, or with ACLF defined by the APASL criteria. Sixty-one serious adverse events were reported in the G-CSF+SMT group and 57 were reported in the SMT group. In total, 7 drug-related serious adverse reactions occurred in the G-CSF group. The study was prematurely terminated due to futility after conditional power calculation. CONCLUSIONS: In contrast to previous findings, G-CSF had no significant beneficial effect on patients with ACLF in this multicenter controlled trial, which suggests that it should not be used as a standard treatment for ACLF. CLINICALTRIALS. GOV NUMBER: NCT02669680 LAY SUMMARY: Granulocyte-colony stimulating factor was considered as a novel treatment for acute-on-chronic liver failure (ACLF). We performed the first randomized, multicenter, controlled phase II trial, which showed that G-CSF did not improve survival or other clinical endpoints in patients with ACLF. Therefore, G-CSF should not be used to treat liver disease outside clinical studies.


Assuntos
Insuficiência Hepática Crônica Agudizada/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/farmacocinética , Insuficiência Hepática Crônica Agudizada/epidemiologia , Insuficiência Hepática Crônica Agudizada/fisiopatologia , Adulto , Idoso , Análise de Variância , Distribuição de Qui-Quadrado , Feminino , Alemanha/epidemiologia , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Estudos Prospectivos
20.
Dig Dis ; 39(1): 52-57, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32777784

RESUMO

BACKGROUND: Abnormal liver function has been reported in patients with COVID-19 infection. The aim of our study was to report on the prevalence of liver injury in our cohort, to evaluate the association of mild versus severe liver injury with mortality in COVID-19 patients and to scrutinize the temporal pattern of viral detection and liver injury. METHODS: We present data from a German cohort of 147 SARS-CoV-2 infected patients. The patients were divided into 3 groups according to their liver status during treatment. The first group included patients without elevated alanine aminotransferase or bilirubin, the third group patients meeting the biochemical criteria of acute liver failure (ALF), and the second group all other patients. RESULTS: Liver injury was detected in 75 (50.7%) and 93 (63%) patients by admission and during treatment, respectively. ALF was associated with the male sex, younger age, and higher BMI. Mortality was associated with the presence of ALF (OR = 9.423, 95% CI: 2.410-36.858) in contrast to milder liver injury (OR 1.101, 95% CI: 0.435-2.791). In 30% of patients with mild liver injury and in 50% of ALF patients, peak liver injury was observed at a time point when the virus was no longer detectable in the respiratory tract. CONCLUSION: Mild liver injury was not associated with worse outcome in our cohort, and the pattern of liver injury did not fit well to the theory of SARS-CoV-2 directly causing liver impairment. Instead, severe liver injury in our cohort was associated multiple-organ failure and acute vascular events.


Assuntos
Alanina Transaminase/sangue , Bilirrubina/sangue , COVID-19 , Falência Hepática Aguda , Testes de Função Hepática , SARS-CoV-2/isolamento & purificação , Adulto , COVID-19/complicações , COVID-19/diagnóstico , COVID-19/mortalidade , Estudos de Coortes , Correlação de Dados , Feminino , Alemanha/epidemiologia , Hospitalização/estatística & dados numéricos , Humanos , Falência Hepática Aguda/sangue , Falência Hepática Aguda/epidemiologia , Falência Hepática Aguda/etiologia , Falência Hepática Aguda/virologia , Testes de Função Hepática/métodos , Testes de Função Hepática/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Prevalência , Índice de Gravidade de Doença
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