Carsten Werner

Publications (146)601.55 Total impact

• Source

  Available from: Kandice Levental

  Article: Defined Polymer-Peptide Conjugates to Form Cell-Instructive starPEG-Heparin Matrices In Situ.

  Mikhail V Tsurkan, Karolina Chwalek, Silvana Prokoph, Andrea Zieris, Kandice R Levental, Uwe Freudenberg, Carsten Werner
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  ABSTRACT: Poly(ethylene glycol)-peptide- and glycosaminoglycan-peptide conjugates obtained by a regio-selective amino acid protection strategy are converted into cell-instructive hydrogel matrices capable of inducing morphogenesis in embedded human vascular endothelial cells and dorsal root ganglia.
  Advanced Materials 04/2013; · 13.88 Impact Factor
• Article: Growth Factor Delivery from Hydrogel Particle Aggregates to Promote Tubular Regeneration after Acute Kidney Injury.

  Mikhail V Tsurkan, Peter V Hauser, Andrea Zieris, Raquel Carvalhosa, Benedetta Bussolati, Uwe Freudenberg, Giovanni Camussi, Carsten Werner
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  ABSTRACT: Local delivery of growth factors (GFs) can accelerate regeneration of injured tissue, but for many medical applications, injectable GF delivery systems are required for clinical success. Viscoelastic, injectable aggregates of micrometer-sized hydrogel particles made of multiarmed polyethylene glycol (starPEG) and heparin were prepared and tested for site-specific paracrine stimulation of tissue regeneration. Heparin was used as it binds, protects and releases numerous GFs. Hydrogel based delivery of basic fibroblast growth factor (bFGF) and murine epidermal growth factor (EGF) was monitored utilizing enzyme-linked immunosorbent assay (ELISA).. bFGF was released slowly because of its high affinity to the heparin while the significantly higher release of the non-specific binding EGF was controlled by diffusion only. To investigate GF delivery in vivo, a hydrogel loaded with murine EGF or bFGF was injected subcapsularly into the left kidney of mice with experimental acute kidney injury caused by glycerol induced rhabdomyolysis. Visual examination confirmed sustained stability of the injected gel aggregates during the timescale of the experiment. The number of proliferating kidney tubular epithelial cells was quantified both in the injected kidney and the non-injected contralateral kidney. bFGF delivery from hydrogels induced a significant increase in cell proliferation in the injected kidney, although small effects were also seen in the non-injected kidney due to a systemic effect. EGF delivery strongly increased cell proliferation for both kidneys, but also showed a local effect on the injected kidney. The hydrogel without loaded GFs was used as a control and showed no increase in cell proliferation. Our results suggest that this novel starPEG-heparin hydrogel system can be an effective approach to deliver GFs locally.
  Journal of Controlled Release 02/2013; · 5.73 Impact Factor
• Article: Minimal Peptide Motif for Non-Covalent Peptide-Heparin Hydrogels.

  Robert Wieduwild, Mikhail V Tsurkan, Karolina Chwalek, Priyanka Murawala, Mirko Nowak, Uwe Freudenberg, Christoph Neinhuis, Carsten Werner, Yixin Zhang
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  ABSTRACT: The reduction of complexity of the extracellular matrix (ECM) to a non-covalent structure with minimal chemically defined components represents an attractive avenue for understanding the biology of the ECM. The resulting system could lead to the design of tailor-made biomaterials that incorporate varying functionalities. Negatively charged glycosaminoglycans are the major component of the ECM. Their interaction with positively charged proteins is important for dynamic three-dimensional scaffold formation and function. We designed and screened minimal peptide motifs whose conjugates with polyethylene glycol interact with heparin to form noncovalent hydrogels. Here we show the structure-function relationship of the (RA)n and (KA)n motifs and determined that both basic residues and the heparin-induced α-helix formation are important for the assembly process. Simple rules allowed us to tune various aspects of the matrix system, such as the gelation rates, bio-degradability, rheological properties, and biofunctionality. The hydrogels can encapsulate cells and support cell survival.
  Journal of the American Chemical Society 02/2013; · 9.91 Impact Factor
• Article: Growth Induction and Low-Oxygen Apoptosis Inhibition of Human CD34(+) Progenitors in Collagen Gels.

  Daniele Avitabile, Katrin Salchert, Carsten Werner, Maurizio C Capogrossi, Maurizio Pesce
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  ABSTRACT: Various reports have indicated low survival of injected progenitors into unfavorable environments such as the ischemic myocardium or lower limb tissues. This represents a major bottleneck in stem-cell-based cardiovascular regenerative medicine. Strategies to enhance survival of these cells in recipient tissues have been therefore sought to improve stem cell survival and ensure long-term engraftment. In the present contribution, we show that embedding human cord blood-derived CD34(+) cells into a collagen I-based hydrogel containing cytokines is a suitable strategy to promote stem cell proliferation and protect these cells from anoxia-induced apoptosis.
  BioMed research international. 01/2013; 2013:542810.
• Article: Human corneal endothelial cell sheets for transplantation: thermo-responsive cell culture carriers to meet cell-specific requirements.

  Juliane Teichmann, Monika Valtink, Stefan Gramm, Mirko Nitschke, Carsten Werner, Richard H W Funk, Katrin Engelmann
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  ABSTRACT: Corneal endothelial diseases lead to severe vision impairment motivating the transplantation of donor corneae or corneal endothelial lamellae, which is however impeded by endothelial cell loss during processing. Therefore, one prioritized aim in corneal tissue engineering is the generation of transplantable human corneal endothelial cell (HCEC) layers. Thermo-responsive cell culture carriers are widely used for non-enzymatic harvest of cell sheets. In the current study, we present a novel thermo-responsive carrier based on simultaneous electron beam immobilization and cross-linking of poly(vinyl methyl ether) (PVME) on polymeric surfaces which allows to adjust layer thickness, stiffness, switching amplitude, and functionalization with bioactive molecules to meet cell type specific requirements. We demonstrate the efficacy of this approach for HCECs, which require elaborate cell culture conditions and are strongly adherent to the substratum. The developed method may pave the way to tissue engineering of corneal endothelium and significantly improve therapeutic options.
  Acta biomaterialia 10/2012; · 3.98 Impact Factor
• Article: Electrokinetic Analysis to Reveal Composition and Structure of Biohybrid Hydrogels.

  Ralf Zimmermann, Susanne Bartsch, Uwe Freudenberg, Carsten Werner
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  ABSTRACT: Biohybrid hydrogels combining electrically neutral synthetic polymers and highly anionic glycosaminoglycans (GAGs) offer exciting options for regenerative therapies as they allow for the electrostatic conjugation of various growth factors. Unraveling details of ionization and structure within such networks defines an important analytical challenge that requires the extension of current methodologies. Here, we present a mean-field approach to quantify the density of ionizable groups, GAG concentration, and cross-linking degree of such hydrogels based on experimental data from microslit electrokinetics and ellipsometry. An exemplary poly(ethylene glycol)-heparin system was analyzed to demonstrate how electrostatic fingerprints of hydrogels obtained by the introduced strategy can sensitively display composition and structure of the polymer networks.
  Analytical Chemistry 10/2012; · 5.86 Impact Factor
• Article: Design and validation of a bioreactor for simulating the cardiac niche: a system incorporating cyclic stretch, electrical stimulation and constant perfusion.

  Liang Lu, Matthias Mende, Xuegeng Yang, Heinz-Felix Körber, Hans-Joachim Schnittler, Sönke Weinert, Jürgen Heubach, Carsten Werner, Ursula Ravens
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  ABSTRACT: To simulate the cardiac niche, a bioreactor system was designed and constructed to incorporate cyclic stretch, rhythmic electrical stimulation and constant perfusion. The homogeneity of surface strain distribution across cell culture substrate was confirmed with ARAMIS deformation analysis. Proliferation marker Ki-67 detected in HUVEC cells and MTT cytotoxicity assay performed on human atrial fibroblasts confirmed biocompatibility of this novel device. Cyclic stretch treatment for 24 hours resulted in perpendicular alignment of human atrial fibroblasts. Electrical stimulation system containing carbon electrodes was characterized by electrochemical impedance spectroscopy (EIS) and charge injection/recovery studies, which indicated that increased corrosive reactions were associated with higher input voltage and prolonged pulse duration. Field stimulation delivered through this system could induce rhythmic contractions in adult rat ventricular myocytes, with contractile characteristics similar to those paced in standard field stimulation chamber. In conclusion, this bioreactor provides a novel tool to study the interaction between physical stimulation and cardiac cell physiology.
  Tissue Engineering Part A 09/2012; · 4.64 Impact Factor
• Article: Polymeric biomaterials for stem cell bioengineering.

  Marina Prewitz, Friedrich Philipp Seib, Tilo Pompe, Carsten Werner
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  ABSTRACT: This review covers the application of polymeric materials in stem cell bioengineering. Main emphasis is directed towards current material design concepts that mimic distinct exogenous signals of the stem cell microenvironment. Progress within the field of stem cell-specific biomaterials will be discussed, focusing on pluripotent, hematopoietic, mesenchymal and neural stem cells. The future role of biomaterials will be outlined with possible applications for cell reprogramming and engineering cancer cell microenvironments.
  Macromolecular Rapid Communications 08/2012; 33(17):1420-31. · 4.60 Impact Factor
• Article: The effect of octadecyl chain immobilization on the hemocompatibility of poly (2-hydroxyethyl methacrylate).

  Marion Fischer, Catarina P Baptista, Inês C Gonçalves, Buddy D Ratner, Claudia Sperling, Carsten Werner, Cristina L Martins, Mário A Barbosa
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  ABSTRACT: Albumin-scavenging surfaces decorated with n-alkyl chains represent an established strategy for blood-contacting applications. To evaluate this concept, a set of poly (2-hydroxyethyl methacrylate) (pHEMA) films modified with different amounts of octadecyl isocyanate (C18) was investigated in an in vitro hemocompatibility assay using freshly drawn human whole blood. In addition, the hydrogel materials were thoroughly characterized with respect to changes in wettability and elasticity, which accompanied the gradual chemical modification of pHEMA. An increase of the surface C18 content induced enhanced hydrophobicity and stiffness. Immobilization of C18 chains was found to substantially reduce the coagulation activation and the complement activation by the pHEMA films. Platelet adhesion and degranulation (PF4 release) were similar on the modified and the unmodified pHEMA. Platelet adhesion to pHEMA hydrogels was lower than the polytetrafluoroethylene reference. We conclude that the immobilization of octadecyl chains improved the hemocompatibility of pHEMA materials under conditions that might be encountered in low shear blood flow.
  Biomaterials 07/2012; 33(31):7677-85. · 7.40 Impact Factor
• Source

  Available from: Jens Friedrichs

  Article: Quantifying the effect of covalently immobilized enzymes on biofilm formation by atomic force microscopy-based single-cell force spectroscopy.

  Jens Friedrichs, Andrea Zieris, Silvana Prokoph, Carsten Werner
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  ABSTRACT: A novel atomic force microscopy-based single-cell force spectroscopy assay to quantify the adhesion of bacterial cells to surfaces was developed. The assay was applied to quantify the effect of two biofilm-degrading enzymes, the protease Subtilisin A and glycoside hydrolase cellulase, on the attachment of the biofilm-forming bacterial strain Cobetia marina. Insights on the mechanism of the initial adhesion and on the nature of the adhesion-mediating molecules were gained. The assay can be easily adapted to various other substrates, different bacterial strains and other fouling species (e.g., algae and diatoms).
  Macromolecular Rapid Communications 07/2012; 33(17):1453-8. · 4.60 Impact Factor
• Article: Macroporous starPEG-heparin cryogels.

  Petra B Welzel, Milauscha Grimmer, Claudia Renneberg, Lisa Naujox, Stefan Zschoche, Uwe Freudenberg, Carsten Werner
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  ABSTRACT: Macroporous scaffolds with adaptable mechanical and biomolecular properties can be instrumental in enabling cell-based therapies. To meet these requirements, a cryostructuration method was adapted to prepare spongy hydrogels based on chemically cross-linked star-shaped poly(ethylene glycol) (starPEG) and heparin. Subzero temperature treatment of the gel forming reaction mixtures and subsequent lyophilization of the incompletely frozen gels resulted in macroporous biohybrid cryogels showing rapid swelling, porosity of up to 92% with interconnected large pores (30-180 μm), low bulk stiffness, and high mechanical stability upon compression. The applicability of the cryogel scaffolds was investigated using human umbilical vein endothelial cells. Cell attachment and three-dimensional spreading resulted in evenly distributed viable cells within the macroporous starPEG-heparin materials, demonstrating the significant translational potential of the developed three-dimensional cell carriers.
  Biomacromolecules 07/2012; 13(8):2349-58. · 5.48 Impact Factor
• Article: A novel, biased-like SDF-1 derivative acts synergistically with starPEG-based heparin hydrogels and improves eEPC migration in vitro.

  Lars Baumann, Silvana Prokoph, Christian Gabriel, Uwe Freudenberg, Carsten Werner, Annette G Beck-Sickinger
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  ABSTRACT: The CXC chemokine stromal cell-derived factor-1α (SDF-1α, CXCL12) has been proven to recruit CXCR4 positive stem and progenitor cells of different sources to defected heart sites, with significant clinical benefits. However, the rapid proteolytic inactivation by inflammation-related proteases, inaccurate drug delivery or inappropriate local concentrations belong to the largest disadvantages for feasible application. Herein, we present a switchable, biased-like SDF-1α variant, AAV-[S4V]-SDF-1α, whose distinct activity is coupled to the inflammation-associated presence of dipeptidylpeptidase-4 (DPP-4), which cleaves an alanine-alanine dipeptide from the precursor. We decorated starPEG-heparin hydrogels with our novel SDF-1α variant and tested them for immobilization efficiency, time-dependent protein release as well as mobilization of early endothelial progenitor cells (eEPCs) in vitro. We found higher migration rates compared to conventional SDF-1α. In summary, we provide a conceptual work on cooperative effects of enzymatically activatable SDF-1α and starPEG-heparin hydrogels.
  Journal of Controlled Release 05/2012; 162(1):68-75. · 5.73 Impact Factor
• Article: Nanoscale characterization of cell receptors and binding sites on cell-derived extracellular matrices.

  Christina Müller, Dimitar R Stamov, Carsten Werner, Tilo Pompe
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  ABSTRACT: Cells are able to adapt their extracellular matrix (ECM) in response to external influences. For instance polymer scaffolds with tunable properties allow for guiding cell adhesion behavior and ECM adaptation in a controlled manner. We propose a new and versatile approach for the investigation of extracellular molecular assemblies at materials interfaces by scanning force microscopy. The distribution of cell adhesion receptors and binding sites of matrix proteins in the investigated ECMs was identified by immunolabeling with 15 nm gold beads. To precisely localize the immunogold in the matrices we utilized electrostatic force microscopy that allows for materials-dependent contrast according to differences in the dielectric properties of the immunolabels. In addition, an image processing routine was developed to localize the immunogold by correlation analysis. The applicability of our approach for nanoscale characterization of cell-derived ECM was further verified in two independent experiments. We probed the distribution of the cell adhesion receptor α(5)β(1) integrin next to its extracellular ligand fibronectin and the corresponding binding site on the fibronectin molecule.
  Ultramicroscopy 05/2012; 118:44-52. · 2.47 Impact Factor
• Article: Using Mean Field Theory to Guide Biofunctional Materials Design

  Uwe Freudenberg, Jens-Uwe Sommer, Kandice R. Levental, Petra B. Welzel, Andrea Zieris, Karolina Chwalek, Katja Schneider, Silvana Prokoph, Marina Prewitz, Ron Dockhorn, Carsten Werner
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  ABSTRACT: Cell-instructive characteristics of extracellular matrices (ECM) resulting from a subtle balance of biomolecular and biophysical signals must be recapitulated in engineered biomaterials to facilitate regenerative therapies. However, no material explored so far allows the independent tuning of the involved molecular and physical cues due to the inherent correlation between biopolymer concentration and material properties. Addressing the resulting challenge, a rational design strategy for ECM-inspired biohybrid hydrogels based on multi-armed poly(ethylene glycol) and heparin, adapting a mean field approach to identify conditions at which the balance of elastic, electrostatic, and excluded volume forces results in constant heparin concentrations within swollen polymer networks with gradually varied physical properties is introduced. Applying heparin-based biofunctionalization schemes, multiple distinct combinations of matrix parameters could be identified to effectively stimulate the pro-angiogenic state of human endothelial cells and the differentiation of human mesenchymal stem cells. The study demonstrates the power of joint theoretical and experimental efforts in creating bioactive materials with specifically and independently controllable characteristics.
  Advanced Functional Materials 04/2012; 22(7):1391. · 10.18 Impact Factor
• Article: Sustained delivery of SDF-1α from heparin-based hydrogels to attract circulating pro-angiogenic cells.

  Silvana Prokoph, Emmanouil Chavakis, Kandice R Levental, Andrea Zieris, Uwe Freudenberg, Stefanie Dimmeler, Carsten Werner
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  ABSTRACT: Enrichment of progenitor cells in ischemic tissue has become a promising therapeutic strategy in the treatment of myocardial infarction. Towards this aim, we report a biology-inspired concept using sulfated glycosaminoglycans to sustainably generate chemokine gradients for the localized accumulation of early endothelial progenitor cells (eEPCs). StarPEG-heparin hydrogels, which have been previously demonstrated to support angiogenesis, were functionalized with SDF-1α, a potent chemoattractant known to act on EPCs. The gels were quantitatively shown to release the chemokine in amounts that are adjustable by the choice of loading concentrations and by matrix metalloprotease (MMP) mediated hydrogel cleavage. Transwell assays confirmed significantly enhanced migration of early EPCs towards concentration gradients of hydrogel-delivered SDF-1α in vitro. Subcutaneous implantation of SDF-1α-releasing gels in mice resulted in massive infiltration of early EPCs and subsequently improved vascularization. In conclusion, sustained delivery of SDF-1α from pro-angiogenic starPEG-heparin hydrogels can effectively attract early EPCs, offering a powerful means to trigger endogenous mechanisms of cardiac regeneration.
  Biomaterials 04/2012; 33(19):4792-800. · 7.40 Impact Factor
• Article: Fluidity modulation of phospholipid bilayers by electrolyte ions: insights from fluorescence microscopy and microslit electrokinetic experiments.

  Ralf Zimmermann, David Küttner, Lars Renner, Martin Kaufmann, Carsten Werner
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  ABSTRACT: Fluidity and charging of supported bilayer lipid membranes (sBLMs) prepared from 1,2-dioleoyl-sn-glycero-3-phosphatidylcholine (DOPC) were studied by fluorescence recovery after photobleaching (FRAP) and microslit electrokinetic measurements at varying pH and ionic composition of the electrolyte. Measurements in neutral electrolytes (KCl, NaCl) revealed a strong correlation between the membrane fluidity and the membrane charging due to unsymmetrical water ion adsorption (OH(-) ≫ H(3)O(+)). The membrane fluidity significantly decreased below the isoelectric point of 3.9, suggesting a phase transition in the bilayer. The interactions of both chaotropic anions and strongly kosmotropic cations with the zwitterionic lipids were found to be related with nearly unhindered lipid mobility in the acidic pH range. While for the chaotropic anions the observed effect correlates with the increased negative net charge at low pH, no correlation was found between the changes in the membrane fluidity and charge in the presence of kosmotropic cations. We discuss the observed phenomena with respect to the interaction of the electrolyte ions with the lipid headgroup and the influence of this process on the headgroup orientation and hydration as well as on the lipid packaging.
  The Journal of Physical Chemistry A 02/2012; 116(25):6519-25. · 2.95 Impact Factor
• Article: Surface modification of cell culture carriers: routes to anhydride functionalization of polystyrene.

  Mirko Nitschke, Serena Ricciardi, Stefan Gramm, Stefan Zschoche, Manuela Herklotz, Paola Rivolo, Carsten Werner
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  ABSTRACT: Physico-chemical and topographical cues allow to control the behavior of adherent cells. Towards this goal, commercially available cell culture carriers can be finished with a laterally microstructured biomolecular functionalization. As shown in a previous study [Biomacromolecules 4 (2003) 1072], the anhydride moiety facilitates a simple and versatile way to protein binding. The present work addresses the technical issue of anhydride surface functionalization of polystyrene, the most common material for cell culture ware. Different approaches based on low pressure plasma, electron beam and ultraviolet light techniques (i.e. maleic anhydride plasma reactions; plasma, electron beam and UV immobilization of functional polymer thin films; grafting of functional polymers to plasma activated surfaces) are introduced and briefly illustrated with examples. Results are characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS) and ellipsometry. The different routes are compared in terms of technical feasibility and achievable surface properties.
  Colloids and surfaces. B, Biointerfaces 02/2012; 90:41-7. · 2.60 Impact Factor
• Source

  Available from: PubMed Central

  Article: In vitro model of metastasis to bone marrow mediates prostate cancer castration resistant growth through paracrine and extracellular matrix factors.

  Reynald M Lescarbeau, F Philipp Seib, Marina Prewitz, Carsten Werner, David L Kaplan
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  ABSTRACT: The spread of prostate cancer cells to the bone marrow microenvironment and castration resistant growth are key steps in disease progression and significant sources of morbidity. However, the biological significance of mesenchymal stem cells (MSCs) and bone marrow derived extracellular matrix (BM-ECM) in this process is not fully understood. We therefore established an in vitro engineered bone marrow tissue model that incorporates hMSCs and BM-ECM to facilitate mechanistic studies of prostate cancer cell survival in androgen-depleted media in response to paracrine factors and BM-ECM. hMSC-derived paracrine factors increased LNCaP cell survival, which was in part attributed to IGFR and IL6 signaling. In addition, BM-ECM increased LNCaP and MDA-PCa-2b cell survival in androgen-depleted conditions, and induced chemoresistance and morphological changes in LNCaPs. To determine the effect of BM-ECM on cell signaling, the phosphorylation status of 46 kinases was examined. Increases in the phosphorylation of MAPK pathway-related proteins as well as sustained Akt phosphorylation were observed in BM-ECM cultures when compared to cultures grown on plasma-treated polystyrene. Blocking MEK1/2 or the PI3K pathway led to a significant reduction in LNCaP survival when cultured on BM-ECM in androgen-depleted conditions. The clinical relevance of these observations was determined by analyzing Erk phosphorylation in human bone metastatic prostate cancer versus non-metastatic prostate cancer, and increased phosphorylation was seen in the metastatic samples. Here we describe an engineered bone marrow model that mimics many features observed in patients and provides a platform for mechanistic in vitro studies.
  PLoS ONE 01/2012; 7(8):e40372. · 4.09 Impact Factor
• Article: The control of endothelial cell adhesion and migration by shear stress and matrix-substrate anchorage.

  Juliane Teichmann, Alexander Morgenstern, Jochen Seebach, Hans-Joachim Schnittler, Carsten Werner, Tilo Pompe
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  ABSTRACT: Endothelial cells constitute the natural inner lining of blood vessels and possess anti-thrombogenic properties. This characteristic is frequently used by seeding endothelial cells on vascular prostheses. As the type of anchorage of adhesion ligands to materials surfaces is known to determine the mechanical balance of adherent cells, we investigated herein the behaviour of endothelial cells under physiological shear stress conditions. The adhesion ligand fibronectin was anchored to polymer surfaces of four physicochemical characteristics exhibiting covalent and non-covalent attachment as well as high and low hydrophobicity. The in situ analysis combined with cell tracking of shear stress-induced effects on cultured isolated cells and monolayers under venous (0.5 dyn/cm(2)) and arterial (12 dyn/cm(2)) shear stress over a time period of 24 h revealed distinct differences in their morphological and migratory features. Most pronounced, unidirectional and bimodal migration patterns of endothelial cells in or against flow direction were found in dependence on the type of substrate-matrix anchorage. Combined by an immunofluorescent analysis of the actin cytoskeleton, cell-cell junctions, cell-matrix adhesions, and matrix reorganization these results revealed a distinct balance of laminar shear stress, cell-cell contacts and substrate-matrix anchorage in affecting endothelial cell fate under flow conditions. This analysis underlines the importance of materials surface parameters as well as primary and secondary adhesion ligand anchorage in the context of artificial blood vessels for future therapeutic devices.
  Biomaterials 12/2011; 33(7):1959-69. · 7.40 Impact Factor
• Article: On the symmetry of siblings: automated single-cell tracking to quantify the behavior of hematopoietic stem cells in a biomimetic setup.

  Nico Scherf, Katja Franke, Ingmar Glauche, Ina Kurth, Martin Bornhäuser, Carsten Werner, Tilo Pompe, Ingo Roeder
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  ABSTRACT: The interplay between hematopoietic stem and progenitor cells (HSPC) and their local microenvironment is a key mechanism for the organization of hematopoiesis. To quantitatively study this process, a time-resolved analysis of cellular dynamics at the single-cell level is an essential prerequisite. One way to generate sufficient amounts of appropriate data is automatic single-cell tracking using time-lapse video microscopy. We describe and apply newly developed computational algorithms that allow for an automated generation of high-content data of single-cell characteristics at high temporal and spatial resolution, together with the reconstruction and statistical evaluation of complete genealogical histories. This methodology has been applied to the particular example of purified primary human HSPCs in bioengineered culture conditions. The combination of genealogical information and dynamic profiles of cellular properties identified a marked symmetry between sibling HSPCs regarding cell cycle time, but also migration speed and growth kinetics. Furthermore, we demonstrate that this symmetry of HSPC siblings can be altered by exogenous cues of the local biomimetic microenvironment. Using the example of HSPC growth in biomimetic culture systems, we show that our approach provides a valuable tool for the quantitative analysis of dynamic single-cell features under defined in vitro conditions, allowing for integration of functional and genealogical data. The efficiency and accuracy of our approach pave the way for new and intriguing insights into the organizational principles of developmental patterns and the respective influence of exogenous cues not limited to the study of primary HSPCs.
  Experimental hematology 11/2011; 40(2):119-30.e9. · 3.11 Impact Factor