TY - THES A1 - Groth, Thomas T1 - Die Bedeutung der Volumen- und Oberflächeneigenschaften von Biomaterialien für die Adsorption von Proteinen und nachfolgende zelluläre Reaktionen N2 - Es ist schon seit längerer Zeit bekannt, dass nach Kontakt des Biomaterials mit der biologischen Umgebung bei Implantation oder extrakorporaler Wechselwirkung zunächst Proteine aus dem umgebenden Milieu adsorbiert werden, wobei die Oberflächeneigenschaften des Materials die Zusammensetzung der Proteinschicht und die Konformation der darin enthaltenden Proteine determinieren. Die nachfolgende Wechselwirkung von Zellen mit dem Material wird deshalb i.d.R. von der Adsorbatschicht vermittelt. Der Einfluss der Oberflächen auf die Zusammensetzung und Konformation der Proteine und die nachfolgende Wechselwirkung mit Zellen ist von besonderem Interesse, da einerseits eine Aussage über die Anwendbarkeit ermöglicht wird, andererseits Erkenntnisse über diese Zusammenhänge für die Entwicklung neuer Materialien mit verbesserter Biokompatibilität genutzt werden können. In der vorliegenden Habilitationsschrift wurde deshalb der Einfluss der Zusammensetzung von Polymeren bzw. von deren Oberflächeneigenschaften auf die Adsorption von Proteinen, den Aktivitätszustand der plasmatischen Gerinnung und die Adhäsion von Zellen untersucht. Dabei wurden auch Möglichkeiten zur Beeinflussung dieser Vorgänge über eine Veränderung der Volumenzusammensetzung oder durch Oberflächenmodifikationen von Biomaterialien vorgestellt. Erkenntnisse aus diesen Arbeiten konnten für die Entwicklung von Membranen für Biohybrid-Organe genutzt werden. N2 - The implantation of biomaterials or the contact of blood with extracorporal devices leads to the rapid adsorption of proteins from the surrounding biological fluids. The surface properties of materials determine the composition of the adsorption layer and the conformation of adsorbed proteins. Hence, the subsequent interaction of cells with biomaterials is dependent on the adsorption layer of proteins. The detailed knowledge on the role of surface properties in protein adsorption and cellular interactions is a useful means to learn about the biomedical applicability of materials and to develop novel materials with improved biocompatibility. The thesis describes the influence of polymer composition and surface properties on protein adsorption, the activation of blood clotting and adhesion of cells. The thesis presents options to modify the reactions of the biological system by the modification of bulk or surface composition of polymers. Results of these studies have been used to develop polymer membranes for biohybrid organs. KW - Biomaterialien KW - Polymere KW - Protein Adsorption KW - Zelladhäsion KW - Biohybride Organe KW - biomaterials KW - polymers KW - protein adsorption KW - cell adhesion KW - biohybrid organs Y1 - 2003 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-0001022 ER - TY - JOUR A1 - Groth, Thomas A1 - Lendlein, Andreas T1 - In-vivo-Reparatur von Blutgefäßen durch alternierende Adsorption von Polyelektrolyten Y1 - 2004 UR - http://www3.interscience.wiley.com/cgi-bin/fulltext/107614315/PDFSTART 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 - 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 - 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 -