Clinical Hemorheology and Microcirculation - Volume 55, issue 4

Authors: Hiebl, B. | Hopperdietzel, C. | Hünigen, H. | Jung, F. | Scharnagl, N.

Article Type: Research Article

Abstract: Despite considerable efforts in biomaterial development there is still a lack on substrates for cardiovascular tissue engineering approaches which allow the establishment of a tight a functional endothelial layer on their surface to provide hemocompatibility. The study aimed to test the biocompatibility of a silicon (Si14 )-based coating substrate (Supershine Medicare, Permanon) which was designed to resist temperatures from −40°C up to 300°C and which allows the use of established heat-inducing sterilization techniques respectively. By X-ray photoelectron spectroscopy it could be validated that this substrate is able to establish a 40–50 nm thick layer of silica, oxygen and carbon without …including any further elements from the substrate on an exemplary selection of materials (silicone, soda-lime-silica glass, stainless steel). Analysis of the LDH-release, the cell activity/proliferation (MTS assay) and the cell phenotype after growing 3T3 cells with extracts of the coated materials did not indicate any signs of cytotoxicity. Additionally by measuring the C5a release after exposure of the coated materials with human serum it could be demonstrated, that the coating had no impact on the activation of the complement system. These results generally suggest the tested substrate as a promising candidate for the coating of materials which are aimed to be used in cardiovascular tissue engineering approaches. Show more

Keywords: Biomaterial, silicon, coating, cardiovascular, tissue engineering

DOI: 10.3233/CH-131785

Citation: Clinical Hemorheology and Microcirculation, vol. 55, no. 4, pp. 491-499, 2013

Authors: Hashimdeen, Shaikh Shimaz | Römhild, Andy | Schmueck, Michael | Kratz, Karl | Lendlein, Andreas | Kurtz, Andreas | Reinke, Petra

Article Type: Research Article

Abstract: When dealing with T lymphocyte culture there is currently very less information available about the interaction between T-cells and the culture system. In this study we look at the influence of the culture chamber on T-cell proliferation in two main aspects of the culture system, namely: culture chamber material and geometry. The study was carried out using unique polymeric closed cell culture inserts, which were processed via injection moulding from polystyrene (PS), polycarbonate (PC), polyetherurethane (PEU), polystyrene-co-acrylonitrile (PSAN) and polyetherimide (PEI). Furthermore culture chamber geometry was studied using commercially available 24, 12 and 6-well plates prepared from tissue culture plastic …(TCP). For T lymphocyte stimulation two methods were used involving either EBV peptide pools or MACS iBead particles depending on the experiment performed. Culture was done with 1645 RPMI medium supplemented with foetal calf serum, penicillin, streptomycin and rhIL-2. We found four materials out of five we tested (PS, PC, PSAN and PEI) exhibited similar fold expansions with minimal influence on proportions of CD4 and CD8, while PEU had a negative influence on T cell growth along with adversely affected CD4/CD8 proportions. Changes in the geometry of TCP had no effect on T cell growth or maturation rather the size of geometry seems to have more influence on proliferation. T-cells appear to prefer smaller geometries during initial stages of culture while towards the end of the culture size becomes less significant to cell proliferation. The parameters tested in this study have significant influences on T-cell growth and are necessary to consider when designing and constructing expansion systems for antigen specific T lymphocytes. This is important when culturing T-cells for immunotherapeutic applications where antigen specificity, T-cell maturation and function should remain unaffected during culture. Show more

Keywords: T-cell culture, immunotherapy, material testing, geometry

DOI: 10.3233/CH-131786

Citation: Clinical Hemorheology and Microcirculation, vol. 55, no. 4, pp. 501-512, 2013

Authors: Rüder, Constantin | Sauter, Tilman | Kratz, Karl | Haase, Tobias | Peter, Jan | Jung, Friedrich | Lendlein, Andreas | Zohlnhöfer, Dietlind

Article Type: Research Article

Abstract: Polymers exhibiting cell-selective effects represent an extensive research field with high relevance for biomedical applications e.g. in the cardiovascular field supporting re-endothelialization while suppressing smooth muscle cell overgrowth. Such an endothelial cell-selective effect could be recently demonstrated for a copolyetheresterurethane (PDC) containing biodegradable poly(p-dioxanone) and poly(ε-caprolactone) segments, which selectively enhanced the adhesion of human umbilical vein endothelial cells (HUVEC) while suppressing the attachment of smooth muscle cells (SMC). In this study we investigated the influence of the fibre orientation (random and aligned) and fibre diameter (2 μm and 500 nm) of electrospun PDC scaffolds on the adhesion, proliferation and apoptosis …of HUVEC and SMC. Adhesion, viability and proliferation of HUVEC was diminished when the fibre diameter was reduced to a submicron scale, while the orientation of the microfibres did only slightly influence the cellular behaviour. In contrast, a submicron fibre diameter improved SMC viability. In conclusion, PDC scaffolds with micron-sized single fibres could be promising candidate materials for cell-selective stent coatings. Show more

Keywords: Endothelialization, drug eluting stent, degradable polymer, electrospinning, cell selectivity

DOI: 10.3233/CH-131787

Citation: Clinical Hemorheology and Microcirculation, vol. 55, no. 4, pp. 513-522, 2013

Authors: König, Josephine | Kohl, Benjamin | Kratz, Karl | Jung, Friedrich | Lendlein, Andreas | Ertel, Wolfgang | Schulze-Tanzil, Gundula

Article Type: Research Article

Abstract: In vitro cultured autologous chondrocytes can be used for implantation to support cartilage repair. For this purpose, a very small number of autologous cells harvested from a biopsy have to be expanded in monolayer culture. Commercially available polymer surfaces lead to chondrocyte dedifferentiation. Hence, the demanding need for optimized polymers and surface topologies supporting chondrocytes' differentiated phenotypes in vitro arises. In this study we explored the effect of tailored cell culture plate inserts prepared from polystyrene (PS) and polyether imide (PEI) exhibiting three different roughness levels (R0, RI, RII) on chondrocyte morphology, metabolism and gene expression profile. As a control, …commercially available tissue culture plastic (TCP) dishes were included. Primary porcine articular chondrocytes were seeded on tailored PS and PEI inserts with three different roughness levels. The metabolic activity of the chondrocytes was determined after 24 hours using alamar blue assay. Chondrocyte gene expression profiles (aggrecan, type I and type II collagen) were monitored after 48 hours using Real Time Detection (RTD)-PCR. Chondrocytes cultured on PS and PEI surfaces formed cell clusters after 24 and 48 hours, which was not observed on TCP. The metabolic activity of chondrocytes cultured on PS was lower than of chondrocytes cultured on PEI, but also lower than on TCP. Gene expression analyses revealed an elevated expression of cartilage-specific aggrecan and an impaired expression of both collagen types by chondrocytes on PS and PEI compared with TCP. In summary, PEI is a biocompatible biomaterial suitable for chondrocyte culturing, which can be further chemically functionalized for generating specific surface interactions or covalent binding of biomolecules. Show more

Keywords: Chondrocytes, polymeric cell culture inserts, surface roughness

DOI: 10.3233/CH-131788

Citation: Clinical Hemorheology and Microcirculation, vol. 55, no. 4, pp. 523-533, 2013

Article Type: Correction

DOI: 10.3233/CH-131805

Citation: Clinical Hemorheology and Microcirculation, vol. 55, no. 4, pp. 535-535, 2013

Article Type: Other

Citation: Clinical Hemorheology and Microcirculation, vol. 55, no. 4, pp. 537-544, 2013