TY  - JOUR
A1  - Bhuvanesh, Thanga
A1  - Saretia, Shivam
A1  - Roch, Toralf
A1  - Schöne, Anne-Christin
A1  - Rottke, Falko O.
A1  - Kratz, Karl
A1  - Wang, Weiwei
A1  - Ma, Nan
A1  - Schulz, Burkhard
A1  - Lendlein, Andreas
T1  - Langmuir-Schaefer films of fibronectin as designed biointerfaces for culturing stem cells
JF  - Polymers for advanced technologies
N2  - Glycoproteins adsorbing on an implant upon contact with body fluids can affect the biological response in vitro and in vivo, depending on the type and conformation of the adsorbed biomacromolecules. However, this process is poorly characterized and so far not controllable. Here, protein monolayers of high molecular cohesion with defined density are transferred onto polymeric substrates by the Langmuir-Schaefer (LS) technique and were compared with solution deposition (SO) method. It is hypothesized that on polydimethylsiloxane (PDMS), a substrate with poor cell adhesion capacity, the fibronectin (FN) layers generated by the LS and SO methods will differ in their organization, subsequently facilitating differential stem cell adhesion behavior. Indeed, atomic force microscopy visualization and immunofluorescence images indicated that organization of the FN layer immobilized on PDMS was uniform and homogeneous. In contrast, FN deposited by SO method was rather heterogeneous with appearance of structures resembling protein aggregates. Human mesenchymal stem cells showed reduced absolute numbers of adherent cells, and the vinculin expression seemed to be higher and more homogenously distributed after seeding on PDMS equipped with FN by LS in comparison with PDMS equipped with FN by SO. These divergent responses could be attributed to differences in the availability of adhesion molecule ligands such as the Arg-Gly-Asp (RGD) peptide sequence presented at the interface. The LS method allows to control the protein layer characteristics, including the thickness and the protein orientation or conformation, which can be harnessed to direct stem cell responses to defined outcomes, including migration and differentiation. Copyright (c) 2016 John Wiley & Sons, Ltd.
KW  - Langmuir-Schaefer method
KW  - protein adsorption
KW  - stem cell adhesion
KW  - cell culture
KW  - fibronectin
Y1  - 2017
U6  - https://doi.org/10.1002/pat.3910
SN  - 1042-7147
SN  - 1099-1581
VL  - 28
SP  - 1305
EP  - 1311
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - JOUR
A1  - Neffe, Axel T.
A1  - von Rüsten-Lange, Maik
A1  - Braune, Steffen
A1  - Lützow, Karola
A1  - Roch, Toralf
A1  - Richau, Klaus
A1  - Jung, Friedrich
A1  - Lendlein, Andreas
T1  - Poly(ethylene glycol) grafting to Poly(ether imide) membranes - influence on protein adsorption and Thrombocyte adhesion
JF  - Macromolecular bioscience
N2  - The chain length and end groups of linear PEG grafted on smooth surfaces is known to influence protein adsorption and thrombocyte adhesion. Here, it is explored whether established structure function relationships can be transferred to application relevant, rough surfaces. Functionalization of poly(ether imide) (PEI) membranes by grafting with monoamino PEG of different chain lengths (M-n=1kDa or 10kDa) and end groups (methoxy or hydroxyl) is proven by spectroscopy, changes of surface hydrophilicity, and surface shielding effects. The surface functionalization does lead to reduction of adsorption of BSA, but not of fibrinogen. The thrombocyte adhesion is increased compared to untreated PEI surfaces. Conclusively, rough instead of smooth polymer or gold surfaces should be investigated as relevant models.
KW  - biomaterials
KW  - poly(ethylene glycol)
KW  - protein adsorption
KW  - surface functionalization
KW  - thrombocyte adhesion
Y1  - 2013
U6  - https://doi.org/10.1002/mabi.201300309
SN  - 1616-5187
SN  - 1616-5195
VL  - 13
IS  - 12
SP  - 1720
EP  - 1729
PB  - Wiley-VCH
CY  - Weinheim
ER  -