Biomolecular Patterning of 3-Dimensional Polymeric Microscaffolds for Targeted Cell Attachment
Final Report Abstract
Within this project two groups from the respective fields of soft matter synthesis (Prof. Barner-Kowollik) and cell biology (Prof. Bastmeyer) have joined forces to develop precision light triggered chemistries for the bio- functionalization of 3-dimensional direct laser written (DLW) polymer micro-scaffolds for targeted cell attachment. The chemistry innovation of the project focused on the development of an advanced set of photoresists, which allow for the coding of disparate and - critically - orthogonal reactivities onto one 3D laser written scaffold. This was realized by exploiting alpha-methyl benzaldehydes (MBAs) as well as phenacylsulfides as functional handles. These co-monomers were subsequently integrated into a basic resist constituted of trifunctional acrylate species and a photoinitiator. By subsequently writing either one or the other functional monomer containing resists, 3D structures become accessible which exhibit on their surface disparate photochemistries. It is critical for the functionality of the final written structures that the monomer-embedded functionalities are lambda-orthogonal to the wavelength of the writing laser so that they are not activated during 3D laser lithography. We thus introduced a powerful photochemical functionalization strategy for 3D printed microstructures for subsequent targeted single cell attachment. We subsequently exploited the established photochemical functionalization techniques for 3D laser printed scaffolds for targeted cell attachment. In vivo cells are embedded in the extracellular matrix (ECM), which represents a complex three-dimensional (3D) network composed of different molecules. Rebuilding this complex natural environment for controlled 3D-culture conditions is one of the mayor challenges in tissue engineering. We succeeded with a strategy based on the combination - via sequential DLW steps - of three photoresists with protein-repellent, controllable protein-binding (via biotinylation of one ECM-Protein), or inherently protein-adhesive properties. To demonstrate the biological relevance of these dual-functionalized microscaffolds, we used combinations of three different ECM-proteins (fibronectin, vitronectin, laminin) and two different cell lines (epithelial A549 cells and NIH 3T3 fibroblasts). Whereas A549 cells almost exclusively adhered to laminin but not to vitronectin, NIH 3T3 cells clearly preferred fibronectin over vitronectin. These experiments constitute the first demonstration of a biologically active functionalization using two distinct ECM proteins in free-standing 3D microscaffolds. With our method a targeted and cell type-specific adhesion behavior can be achieved and thus constitutes a powerful platform for gaining general knowledge of cellular responses to multiple extracellular cues.
Publications
- (2017) Stepwise Light-Induced Dual Compaction of Single-Chain Nanoparticles. Macromolecular rapid communications 38 (16)
Claus, Tanja K.; Zhang, Junliang; Martin, Liam; Hartlieb, Matthias; Mutlu, Hatice; Perrier, Sébastien; Delaittre, Guillaume; Barner-Kowollik, Christopher
(See online at https://doi.org/10.1002/marc.201700264) - "Simultaneous Dual Encoding of 3D Structures via Light-induced Modular Ligation". Angew. Chem. Int. Ed. 2016, 55, 3817-3822
Claus, T. K.; Richter, B.; Hahn, V.; Welle, A.; Kayser, S.; Wegener, M.; Bastmeyer, M.; Delaittre, G.; Barner-Kowollik, C.
(See online at https://doi.org/10.1002/anie.201509937) - "Guiding Cell Attachment in Three-Dimensional Microscaffolds Selectively Functionalized with Two Distinct Adhesion Proteins". Adv. Mat. 2017, 29, 1604342
Richter, B.; Hahn, V.; Bertels, S.; Claus, T. C.; Wegener, M.; Delaittre, G.; Barner-Kowollik, C.; Bastmeyer, M.
(See online at https://doi.org/10.1002/adma.201604342) - "Light-driven Reversible Surface Functionalization with Anthracenes: Visible Light Writing and Mild UV Erasing". Chem. Commun. 2017, 53, 1599-1602
Claus, T. K.; Telitel, S.; Welle, A.; Bastmeyer, M.; Vogt, A. P.; Delaittre, G.; Barner-Kowollik, C.
(See online at https://doi.org/10.1039/c6cc09897e) - “3D Laser Micro- and Nano-Printing: Challenges for Chemistry”. Angew. Chem. Int. Ed. 2017
Barner Kowollik, C.; M Bastmeyer M.; Blasco E.; Mueller P.; Delaittre G.; Richter B.; Wegener M.
(See online at https://doi.org/10.1002/anie.201704695) - “Tension and Elasticity Contribute to Fibroblast Cell Shape in Three Dimensions”. Biophysical J. 2017
Brand C.; Linke M.; Weißenbruch K.; Richter B.; Bastmeyer M.; Schwarz U.S.
(See online at https://doi.org/10.1016/j.bpj.2017.06.058)
