TY  - JOUR
A1  - Shan, Junwen
A1  - Böck, Thomas
A1  - Keller, Thorsten
A1  - Forster, Leonard
A1  - Blunk, Torsten
A1  - Groll, Jürgen
A1  - Teßmar, Jörg
T1  - TEMPO/TCC as a Chemo Selective Alternative for the Oxidation of Hyaluronic Acid
JF  - Molecules
N2  - Hyaluronic acid (HA)-based hydrogels are very commonly applied as cell carriers for different approaches in regenerative medicine. HA itself is a well-studied biomolecule that originates from the physiological extracellular matrix (ECM) of mammalians and, due to its acidic polysaccharide structure, offers many different possibilities for suitable chemical modifications which are necessary to control, for example, network formation. Most of these chemical modifications are performed using the free acid function of the polymer and, additionally, lead to an undesirable breakdown of the biopolymer’s backbone. An alternative modification of the vicinal diol of the glucuronic acid is oxidation with sodium periodate to generate dialdehydes via a ring opening mechanism that can subsequently be further modified or crosslinked via Schiff base chemistry. Since this oxidation causes a structural destruction of the polysaccharide backbone, it was our intention to study a novel synthesis protocol frequently applied to selectively oxidize the C6 hydroxyl group of saccharides. On the basis of this TEMPO/TCC oxidation, we studied an alternative hydrogel platform based on oxidized HA crosslinked using adipic acid dihydrazide as the crosslinker.
KW  - hyaluronic acid
KW  - oxidation
KW  - hydrogel formation
KW  - Schiff base chemistry
Y1  - 2021
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-248362
SN  - 1420-3049
VL  - 26
IS  - 19
ER  - 
TY  - JOUR
A1  - Robertson, Kevin A.
A1  - Hsieh, Wei Yuan
A1  - Forster, Thorsten
A1  - Blanc, Mathieu
A1  - Lu, Hongjin
A1  - Crick, Peter J.
A1  - Yutuc, Eylan
A1  - Watterson, Steven
A1  - Martin, Kimberly
A1  - Griffiths, Samantha J.
A1  - Enright, Anton J.
A1  - Yamamoto, Mami
A1  - Pradeepa, Madapura M.
A1  - Lennox, Kimberly A.
A1  - Behlke, Mark A.
A1  - Talbot, Simon
A1  - Haas, Jürgen
A1  - Dölken, Lars
A1  - Griffiths, William J.
A1  - Wang, Yuqin
A1  - Angulo, Ana
A1  - Ghazal, Peter
T1  - An Interferon Regulated MicroRNA Provides Broad Cell-Intrinsic Antiviral Immunity through Multihit Host-Directed Targeting of the Sterol Pathway
JF  - PLoS Biology
N2  - In invertebrates, small interfering RNAs are at the vanguard of cell-autonomous antiviral immunity. In contrast, antiviral mechanisms initiated by interferon (IFN) signaling predominate in mammals. Whilst mammalian IFN-induced miRNA are known to inhibit specific viruses, it is not known whether host-directed microRNAs, downstream of IFN-signaling, have a role in mediating broad antiviral resistance. By performing an integrative, systematic, global analysis of RNA turnover utilizing 4-thiouridine labeling of newly transcribed RNA and pri/pre-miRNA in IFN-activated macrophages, we identify a new post-transcriptional viral defense mechanism mediated by miR-342-5p. On the basis of ChIP and site-directed promoter mutagenesis experiments, we find the synthesis of miR-342-5p is coupled to the antiviral IFN response via the IFN-induced transcription factor, IRF1. Strikingly, we find miR-342-5p targets mevalonate-sterol biosynthesis using a multihit mechanism suppressing the pathway at different functional levels: transcriptionally via SREBF2, post-transcriptionally via miR-33, and enzymatically via IDI1 and SC4MOL. Mass spectrometry-based lipidomics and enzymatic assays demonstrate the targeting mechanisms reduce intermediate sterol pathway metabolites and total cholesterol in macrophages. These results reveal a previously unrecognized mechanism by which IFN regulates the sterol pathway. The sterol pathway is known to be an integral part of the macrophage IFN antiviral response, and we show that miR-342-5p exerts broad antiviral effects against multiple, unrelated pathogenic viruses such Cytomegalovirus and Influenza A (H1N1). Metabolic rescue experiments confirm the specificity of these effects and demonstrate that unrelated viruses have differential mevalonate and sterol pathway requirements for their replication. This study, therefore, advances the general concept of broad antiviral defense through multihit targeting of a single host pathway.
KW  - microRNA
KW  - sterol pathway
KW  - multihit targeting
KW  - interferon signaling
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-166666
VL  - 14
IS  - 3
ER  -