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Oberwallner B.,Berlin Brandenburg Center for Regenerative Therapies | Brodarac A.,Berlin Brandenburg Center for Regenerative Therapies | Anic P.,Berlin Brandenburg Center for Regenerative Therapies | Saric T.,University of Cologne | And 4 more authors.
European Journal of Cardio-thoracic Surgery | Year: 2015

OBJECTIVES: Cross-talk between organ-specific extracellular matrix (ECM) and stem cells is often assumed but has not been directly demonstrated. We developed a protocol for the preparation of human cardiac ECM (cECM) and studied whether cECM has effects on pluripotent stem cell differentiation that may be useful for future cardiac regeneration strategies in patients with end-stage heart failure. METHODS: Of note, 0.3 mm-thick cECM slices were prepared from samples of myocardium from patients with end-stage non-ischaemic dilated cardiomyopathy, using a three-step protocol involving hypotonic lysis buffer, sodium dodecyl sulphate (SDS) and foetal bovine serum (FBS). Murine embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs) and mesenchymal stromal cells (MSCs) were seeded and grown in standard culture, on cECM or on non-specific ECM preparations (Matrigel® or Geltrex®). Cell attachment, apoptosis induction (Caspase 3/7 activity) and metabolic activity (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2Htetrazolium conversion) were followed. Transcriptional activation of genes involved in pluripotency; early and late myocardial development; and endothelial, ectodermal or endodermal commitment were monitored by quantitative real-time polymerase chain reaction (rtPCR). Protein expression of selected markers was confirmed by immunohistology. RESULTS: cECM supported the proliferation of ESCs and iPSCs, and Caspase 3/7 activity was significantly lower compared with standard culture. Cardiac lineage commitment was favoured when ESCs or iPSCs were grown on cECM, as evidenced by the significantly increased mRNA expression of cardiac alpha myosin heavy polypeptide 6 (Myh6), cardiac troponin T2 (Tnnt2) and NK2 homeobox 5 (Nkx2.5) as well as positive immunohistology for cardiac troponin T and heavy-chain cardiac myosin protein. In contrast, Matrigel or Geltrex did not induce cardiac-specific markers. MSCs showed no evidence of cardiomyocyte differentiation. CONCLUSIONS: Human cardiac ECM seems to direct differentiation of pluripotent stem cells towards a cardiomyocyte phenotype. This phenomenon supports the use of cardiac ECM preparations for guided stem cell differentiation and myocardial repair, and may ultimately increase the therapeutic efficacy of cell therapy in heart failure patients. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. Source


Wellnhofer E.,Deutsches Herzzentrum Berlin DHZB
Public Health Forum | Year: 2016

Coronary artery disease is a chronic inflammatory disease of coronary arteries. It is still the most prevalent cause of death in Germany. The 27. Herzbericht 2015 reports current prevalence and disease management covering in-patient and ambulatory sectors. This paper highlights and discusses selected data from this report. Moreover, emerging trends in management of coronary artery disease are discussed. Source


Oberwallner B.,Berlin Brandenburg Center for Regenerative Therapies | Brodarac A.,Berlin Brandenburg Center for Regenerative Therapies | Choi Y.-H.,University of Cologne | Saric T.,University of Cologne | And 3 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2014

Extracellular matrix (ECM) derived by tissue decellularization has applications as a tissue engineering scaffold and for support of cellular regeneration. Myocardial ECM from animals has been produced by whole-organ perfusion or immersion processes, but methods for preparation of human myocardial ECM for therapy and research have not been compared in detail, yet. We analyzed the impact of decellularization processes on human myocardial ECM, and tested its ability to serve as a scaffold for cell seeding. Sodium dodecyl sulfate (SDS)-based decellularization, but not treatments based on Triton X-100, deoxycholate or hypo/hypertonic incubations, removed cells satisfactorily, and incubation with fetal bovine serum (FBS) eliminated residual DNA. ECM architecture was best preserved by a protocol consisting of 2 h lysis, 6 h SDS, and 3 h FBS, but age and pathology of the donor tissue are highly important for producing reproducible, high-quality scaffolds. We also studied ECM repopulation with mesenchymal stem cells (CB-MSC), cardiomyocytes derived from induced pluripotent stem cells (iPS-CM), and naïve neonatal mouse cardiomyocytes. Cells attached to the matrix and proliferated and displayed higher viability than in standard culture. We conclude that human cardiac ECM sheets may be suitable scaffold for cell-matrix interaction studies and as a biomaterial for tissue regeneration and engineering. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3263-3272, 2014 © 2013 Wiley Periodicals, Inc. Source


Krenzlin H.,Charite - Medical University of Berlin | Rosenthal C.,Charite - Medical University of Berlin | Wolf S.,Charite - Medical University of Berlin | Vierecke J.,Deutsches Herzzentrum Berlin DHZB | And 4 more authors.
Acta Neurochirurgica | Year: 2014

Background: Cranial intraparenchymal hemorrhage represents a critical complication of mechanical circulatory support requiring constant antithrombotic treatment. Surgery of intraparenchymal hemorrhage under anticoagulation represents a challenge and imposes significant risks for patients. It was the aim to analyse surgical and clinical outcome of patients requiring surgical treatment due to intraparenchymal hemorrhage. Methods: Patients with mechanical circulatory support requiring surgical therapy due to space-occupying lobar supratentorial or infratentorial hemorrhage from January 1, 2009 to January 1, 2014 were included in our study. Baseline parameters are preoperative International Normalized Ratio (INR) values, postoperative anticoagulation regiment, bleeding size and localization. Co-primary outcome parameters were the extent of hematoma evacuation and the Modified Rankin Scale at discharge from hospital. Secondary outcome parameters included rate of recurrent hemorrhage, rate of revision surgery and in-hospital mortality. Results: Twelve patients (mean age 44 ± 18 years, nine supratentorial-/three infratentorial hemorrhages, 11 left ventricular assist devices, and one extracorporeal membrane oxygenation) were included. Surgical hematoma evacuation was performed in 11 patients, one patient received decompressive hemicraniectomy. Hematoma evacuation was complete in no patients, and partial in 11 patients. Initial INR was 2,7 ± 1,6. Rate of recurrent hemorrhage was 75 %. Revision surgery was performed in three patients achieving partial hematoma evacuation in two patients and complete evacuation in one patient. Modified Rankin Scale at discharge from hospital was six in nine patients (in-hospital mortality of 75 %), five in two patients and four in one patient. Conclusions: Surgical treatment of life threatening, space-occupying intraparenchymal hemorrhage under mechanical circulation support is of limited efficacy with high rates of recurrent hemorrhage and in-hospital mortality. We provide additional data that postponing anticoagulation is feasible and may lead to improved clinical outcome and survival. © 2014 Springer-Verlag. Source


Posch M.G.,Deutsches Herzzentrum Berlin DHZB | Posch M.G.,Charite Research Organisation GmbH | Schmidt G.,Deutsches Herzzentrum Berlin DHZB | Steinhoff L.,Max Delbruck Center for Molecular Medicine | And 6 more authors.
European Journal of Cardio-thoracic Surgery | Year: 2014

OBJECTIVES: Mechanical circulatory support (MCS) creates improvement of cardiac function in a small portion of patients with idiopathic dilated cardiomyopathy (iDCM). Among other factors, cardiomyocyte hypertrophy seems to represent an important prerequisite for MCS-related cardiac recovery. We have previously shown that connective tissue growth factor (CTGF) leads to adaptive cardiomyocyte hypertrophy associated with a protective cardiac function in transgenic mice. To test whether a functional genetic variant in the CTGF promoter impacts MCS-related cardiac recovery, three groups of iDCM patients with and without cardiac recovery on MCS were genotyped. METHODS: The CTGF promoter variant (c.-945C>G) was analysed in 314 patients with iDCM receiving medical treatment only (Group I). Forty-nine iDCM patients who were either weaned from MCS for more than 6 months (Group II; n = 20) or bridged to cardiac transplantation (Group III: n = 29) were also genotyped. Patients on MCS were followed up for at least 12 months. Clinical characteristics and outcome on MCS were correlated with the respective genotypes. RESULTS: The c.-945C>G allele frequencies in 314 iDCM patients (Group I) were similar to controls deposited in the HapMap database or those published in a recent study. There were no differences in allele prevalence between patients with mild to moderate iDCM (Group I) compared with patients with severe iDCM requiring MCS (Groups II and III). Intriguingly, 50% of patients who were weaned from MCS (Group II) were homozygous for the G allele compared with only 17.2% of patients included in Group III, which is a significant difference (P = 0.03). CONCLUSIONS: Homozygosity of the promoter-activating G allele in the CTGF_c.-945C>G variant is overrepresented in patients with cardiac recovery on MCS when compared with iDCM patients without cardiac recovery. Further studies are needed to evaluate c.-945C>G as a genetic predictor for clinical outcome on MCS. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved. Source

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