TY  - JOUR
A1  - Hahn, Lukas
A1  - Beudert, Matthias
A1  - Gutmann, Marcus
A1  - Keßler, Larissa
A1  - Stahlhut, Philipp
A1  - Fischer, Lena
A1  - Karakaya, Emine
A1  - Lorson, Thomas
A1  - Thievessen, Ingo
A1  - Detsch, Rainer
A1  - Lühmann, Tessa
A1  - Luxenhofer, Robert
T1  - From Thermogelling Hydrogels toward Functional Bioinks: Controlled Modification and Cytocompatible Crosslinking
JF  - Macromolecular Bioscience
N2  - Hydrogels are key components in bioink formulations to ensure printability and stability in biofabrication. In this study, a well-known Diels-Alder two-step post-polymerization modification approach is introduced into thermogelling diblock copolymers, comprising poly(2-methyl-2-oxazoline) and thermoresponsive poly(2-n-propyl-2-oxazine). The diblock copolymers are partially hydrolyzed and subsequently modified by acid/amine coupling with furan and maleimide moieties. While the thermogelling and shear-thinning properties allow excellent printability, trigger-less cell-friendly Diels-Alder click-chemistry yields long-term shape-fidelity. The introduced platform enables easy incorporation of cell-binding moieties (RGD-peptide) for cellular interaction. The hydrogel is functionalized with RGD-peptides using thiol-maleimide chemistry and cell proliferation as well as morphology of fibroblasts seeded on top of the hydrogels confirm the cell adhesion facilitated by the peptides. Finally, bioink formulations are tested for biocompatibility by incorporating fibroblasts homogenously inside the polymer solution pre-printing. After the printing and crosslinking process good cytocompatibility is confirmed. The established bioink system combines a two-step approach by physical precursor gelation followed by an additional chemical stabilization, offering a broad versatility for further biomechanical adaptation or bioresponsive peptide modification.
KW  - chemical crosslinking
KW  - biofabrication
KW  - bioprinting
KW  - hydrogels
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-257542
VL  - 21
IS  - 10
ER  - 
TY  - JOUR
A1  - Altmann, Stephan
A1  - Mut, Jürgen
A1  - Wolf, Natalia
A1  - Meißner-Weigl, Jutta
A1  - Rudert, Maximilian
A1  - Jakob, Franz
A1  - Gutmann, Marcus
A1  - Lühmann, Tessa
A1  - Seibel, Jürgen
A1  - Ebert, Regina
T1  - Metabolic glycoengineering in hMSC-TERT as a model for skeletal precursors by using modified azide/alkyne monosaccharides
JF  - International Journal of Molecular Sciences
N2  - Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac\(_4\)ManNAz) and N-alkyneacetylmannosamine (Ac\(_4\)ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac\(_4\)ManNAz was detectable for up to six days while Ac\(_4\)ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.
KW  - hMSC-TERT
KW  - metabolic glycoengineering
KW  - glycocalyx
KW  - modified monosaccharides
KW  - click chemistry
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259247
SN  - 1422-0067
VL  - 22
IS  - 6
ER  -