Publications by authors named "Joanna Freyse"

Transglutaminases (TGs) catalyze the covalent crosslinking of proteins via isopeptide bonds. The most prominent isoform, TG2, is associated with physiological processes such as extracellular matrix (ECM) stabilization and plays a crucial role in the pathogenesis of e.g.

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Cytokines such as interleukin-8 activate the immune system during infection and interact with sulfated glycosaminoglycans with specific sulfation patterns. In some cases, these interactions are mediated by metal ion binding which can be used to tune surface-based glycan-protein interactions. We evaluated the effect of both hyaluronan sulfation degree and Fe on interleukin-8 binding by electrochemical impedance spectroscopy and surface characterizations.

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The delivery of chemotactic signaling molecules via customized biomaterials can effectively guide the migration of cells to improve the regeneration of damaged or diseased tissues. Here, we present a novel biohybrid hydrogel system containing two different sulfated glycosaminoglycans (sGAG)/sGAG derivatives, namely either a mixture of short heparin polymers (Hep-Mal) or structurally defined nona-sulfated tetrahyaluronans (9s-HA4-SH), to precisely control the release of charged signaling molecules. The polymer networks are described in terms of their negative charge, i.

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Glycosaminoglycans (GAG) as long, unbranched polysaccharides are major components of the extracellular matrix. Many studies provided additional evidence of a specific binding between mediators and sulfated GAG, at which the sulfation code-which means the number and positions of sulfate groups along the polysaccharide chain-plays an important role. GAG from natural sources are very inhomogeneous regarding their sulfation patterns and molecular weight.

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Glycosaminoglycans (GAGs) are a physio- and pharmacologically highly relevant class of complex saccharides, possessing a linear sequence and strongly acidic character. Their repetitive linear core makes them seem structurally simple at first glance, yet differences in sulfation and epimerization lead to an enormous structural diversity with only a few GAGs having been successfully characterized to date. Recent infrared action spectroscopic experiments on sulfated mono- and disaccharide ions show great promise.

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Pathological healing characterized by abnormal angiogenesis presents a serious burden to patients' quality of life requiring innovative treatment strategies. Glycosaminoglycans (GAG) are important regulators of angiogenic processes. This experimental and computational study revealed how sulfated GAG derivatives (sGAG) influence the interplay of vascular endothelial growth factor (VEGF) and its heparin-binding domain (HBD) with the signaling receptor VEGFR-2 up to atomic detail.

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