TY - JOUR A1 - Rickert, D. A1 - Lendlein, Andreas A1 - Schmidt, A. M. A1 - Kelch, S. A1 - Roehlke, W. A1 - Fuhrmann, R. A1 - Franke, R. P. T1 - In vitro cytotoxicity testing of AB-polymer networks based on oligo(epsilon-caprolactone) segments after different sterilization techniques Y1 - 2003 ER - TY - JOUR A1 - Rickert, D. A1 - Moses, M. A. A1 - Lendlein, Andreas A1 - Kelch, S. A1 - Franke, R. P. T1 - The importance of angiogenesis in the interaction between polymeric biomaterials and surrounding tissue Y1 - 2003 ER - TY - JOUR A1 - Kelch, S. A1 - Lendlein, Andreas A1 - Müllen, A. A1 - Ridder, U. T1 - Textile Polymer Scaffolds for Tissue Engineering Y1 - 2003 ER - TY - JOUR A1 - Lendlein, Andreas A1 - Kelch, S. A1 - Schulte, J. A1 - Kratz, K. T1 - Shape-memory polymers Y1 - 2004 ER - TY - JOUR A1 - Groth, Thomas A1 - Lendlein, Andreas T1 - Layer-by-layer deposition of polyelectrolytes : a versatile tool for the in vivo repair of blood vessels and the preparation of biocompatible implant coatings Y1 - 2004 ER - TY - JOUR A1 - Binzen, Eva A1 - Lendlein, Andreas A1 - Kelch, S. A1 - Rickert, D. A1 - Franke, R. P. T1 - Biomaterial-microvasculature interaction on polymers after implantation in mice Y1 - 2004 ER - TY - JOUR A1 - Heilmann, Katja A1 - Groth, Thomas A1 - Behrsing, Olaf A1 - Wagner, Albrecht A1 - Schossig-Tiedemann, Michael A1 - Lendlein, Andreas A1 - Micheel, Burkhard T1 - The influence of the chemical composition of cell culture material on the growth and antibody production of hybridoma cells N2 - The multiplication and antibody production of murine hybridoma cells cultured on five different polymer membranes were tested and compared with conventional tissue culture polystyrene (TCPS). Membranes were prepared from polyacrylonitrile (PAN) and acrylonitrile copolymerized with N-vinylpyrrolidone (NVP20, NVP30), Na-methallylsulfonate (NaMAS) and N-(3-amino-propyl-methacrylamide-hydrochloride) (APMA). Cell number and antibody concentration were quantified as criteria for viability and productivity. Adhesion of hybridoma cells was characterized by vital and scanning electron microscopy. The results suggest that a strong adhesion of cells, observed on APMA and TCPS, increased cell growth but reduced monoclonal antibody production. In contrast membranes with lowered adhesivity such as NVP20 provided favourable conditions for monoclonal antibody production. In addition it was shown that this membrane also possessed a minor fouling as indicated by the low decrease of water flux across the membrane after protein adsorption. It was concluded that NVP20 could be a suitable material for the development of hollow fibre membranes for bioreactors. Y1 - 2005 UR - http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T3C-4DPYNGY- 4&_coverDate=02%2F09%2F2005&_alid=268995355&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=4943&_sort=d&view=c&_acct=C000053886&_v e ER - TY - JOUR A1 - Rickert, D A1 - Lendlein, Andreas A1 - Kelch, S A1 - Franke, R. P. A1 - Moses, M. A. T1 - Cell proliferation and cellular activity of primary cell cultures of the oral cavity after cell seeding on the surface of a degradable, thermoplastic block copolymer N2 - Using standard cell biological and biochemical methods we were able to test the ability of a degradable, thermoplastic block copolymer to support the adhesion, proliferation, and the cellular activity of primary cell cultures of the oral cavity in vitro. The delicate balance between a group of endogenous enzymes, Matrix Metalloproteinases (MMPs), and their inhibitors (Tissue Inhibitor of MMPs, TIMPs) have a decisive function in the remodeling of the extracellular matrix during processes like wound healing or the integration of biomaterials in surrounding tissues after implantation. Recently developed, biodegradable thermoplastic elastomers with shape-memory properties may be the key to develop new therapeutical options in head and neck surgery. Primary cell cultures of the oral cavity of Sprague-Dawley rats were seeded on the surface of a thermoplastic block copolymer and on a polystyrene surface as control. Conditioned media of the primary cells were analyzed for MMPs and TIMPs after different periods of cell growth. The MMP and TIMP expression was analysed by zymography and a radiometric enzyme assay. No statistically significant differences in the appearance and the kinetic of MMP-1, MMP-2, MMP-9 and TIMPs were detected between cells grown on the polymer surface compared to the control. An appropriate understanding of the molecular processes that regulate cellular growth and integration of a biomaterial in surrounding tissue is the requirement for an optimal adaptation of biodegradable, polymeric biomaterials to the physiological, anatomical, and surgical conditions in vivo to develop new therapeutic options in otolaryngology and head and neck surgery Y1 - 2005 ER - TY - JOUR A1 - Heilmann, Katja A1 - Groth, Thomas A1 - Schossig, Michael A1 - Lendlein, Andreas A1 - Micheel, Burkhard T1 - Modulation of hybridoma cell growth and antibody production by coating cell culture material with extracellular matrix proteins N2 - The influence of coating polystyrene tissue culture plates with different proteins on murine hybridoma cell growth and antibody production was investigated. Fibronectin, collagen I, bovine serum albumin and laminin were used to coat NUNC and COSTAR cell culture plates. Cell number and antibody concentration in culture fluids were quantified as indicators for cell viability, proliferation and productivity. Adhesive behaviour, morphology, expression of surface receptors of hybridoma cells and the presence of tyrosine-phosphorylated proteins in cell lysates were characterized by cell adhesion experiments, microscopy, flow cytometry and Western Blot analysis. It was shown that coatings with fibronectin (0.2 ;g/ml) lead to a substantial improvement of cell growth by 50-70% and an increase of monoclonal antibody production by 100-120%. Collagen I coatings showed an improvement in cell growth by 30-70% and by 60% for the production of monoclonal antibodies. Coatings with BSA and laminin had minor effects on these parameters. It was found that the hybridoma cell lines used in this study did not express the ;2-chain of the ;2;1-integrin, which is responsible for binding to collagen and laminin. However, the presence of ;1- integrin on the cell surface was shown, which should enable hybridoma cells to bind fibronectin. We propose, therefore, that fibronectin adsorption to cell culture materials may be a promising approach to enhance the production of monoclonal antibodies by cultivated hybridoma cells. Y1 - 2007 UR - http://www.sciencedirect.com/science/journal/1369703X U6 - https://doi.org/10.1016/j.bej.2007.01.035 SN - 1369-703X ER - TY - JOUR A1 - Tronci, Giuseppe A1 - Neffe, Axel T. A1 - Pierce, Benjamin Franklin A1 - Lendlein, Andreas T1 - An entropy-elastic gelatin-based hydrogel system N2 - Gelatin is a non-immunogenic and degradable biopolymer, which is widely applied in the biomedical field e. g. for drug capsules or as absorbable hemostats. However, gelatin materials present limited and hardly reproducible mechanical properties especially in aqueous systems, particularly caused by the uncontrollable partial renaturation of collagen-like triple helices. Therefore, mechanically demanding applications for gelatin-based materials, such as vascular patches, i.e. hydrogel films that seal large incisions in vessel walls, and for induced autoregeneration, are basically excluded if this challenge is not addressed. Through the synthesis of a defined chemical network of gelatin with hexamethylene diisocyanate (HDI) in DMSO, the self-organization of gelatin chains could be hindered and amorphous gelatin films were successfully prepared having Young's moduli of 60-530 kPa. Transferring the crosslinking reaction with HDI and, alternatively, ethyl lysine diisocyanate (LDI), to water as reaction medium allowed the tailoring of swelling behaviour and mechanical properties by variation of crosslinker content while suppressing the formation of helices. The hydrogels had Young's moduli of 70-740 kPa, compressive moduli of 16-48 kPa, and degrees of swelling of 300-800 vol%. Test reactions investigated by ESI mass spectrometry allowed the identification and quantification of reaction products of the crosslinking reaction. The HDI crosslinked networks were stabilized by direct covalent crosslinks (ca. 10 mol%), supported by grafting (50 mol%) and blending of hydrophobic oligomeric chains. For the LDI- based networks, less crosslinked (3 mol%) and grafted species (5 mol%) and much higher amounts of oligomers were observed. The adjustable hydrogel system enables the application of gelatin-based materials in physiological environments. Y1 - 2010 UR - http://www.rsc.org/Publishing/Journals/jm/index.asp U6 - https://doi.org/10.1039/C0jm00883d SN - 0959-9428 ER -