Browse
Submit Data
Databases
API
Help

Dataset Information

32 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Interfacial Bioorthogonal Cross-Linking.

ABSTRACT: Described herein is interfacial bioorthogonal cross-linking, the use of bioorthogonal chemistry to create and pattern biomaterials through diffusion-controlled gelation at the liquid-gel interface. The basis is a rapid (k₂ 284000 M^-1 s^-1) reaction between strained trans-cyclooctene (TCO) and tetrazine (Tz) derivatives. Syringe delivery of Tz-functionalized hyaluronic acid (HA-Tz) to a bath of bis-TCO cross-linker instantly creates microspheres with a cross-linked shell through which bis-TCO diffuses freely to introduce further cross-linking at the interface. Tags can be introduced with 3D resolution without external triggers or templates. Water-filled hydrogel channels were prepared by simply reversing the order of addition. Prostate cancer cells encapsulated in the microspheres have 99% viability, proliferate readily, and form aggregated clusters. This process is projected to be useful in the fabrication of cell-instructive matrices for in vitro tissue models.

SUBMITTER: Zhang H

PROVIDER: S-EPMC4144716 | biostudies-literature | 2014 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Interfacial Bioorthogonal Cross-Linking.

Zhang Han H Dicker Kevin T KT Xu Xian X Jia Xinqiao X Fox Joseph M JM

ACS macro letters 20140714 8

Described herein is interfacial bioorthogonal cross-linking, the use of bioorthogonal chemistry to create and pattern biomaterials through diffusion-controlled gelation at the liquid-gel interface. The basis is a rapid (k2 284000 M-1 s-1) reaction between strained trans-cyclooctene (TCO) and tetrazine (Tz) derivatives. Syringe delivery of Tz-functionalized hyaluronic acid (HA-Tz) to a bath of bis-TCO cross-linker instantly creates microspheres with ...[more]

PMID: 25177528

Similar Datasets

Spatial Patterning of Molecular Cues and Vascular Cells in Fully Integrated Hydrogel Channels via Interfacial Bioorthogonal Cross-Linking.

Project description:Fully integrated hydrogel channels were fabricated via interfacial bioorthogonal cross-linking, a diffusion-controlled method for the creation and patterning of synthetic matrices based on the rapid bioorthogonal reaction between s-tetrazines (Tz) and trans-cyclooctene (TCO) dienophiles. Injecting an aqueous solution of a bisTCO cross-linker into a reservoir of tetrazine-modified hyaluronic acid (HA-Tz), while simultaneously drawing the syringe needle through the reservoir, yielded a cross-linked hydrogel channel that was mechanically robust. Fluorescent tags and biochemical signals were spatially patterned into the channel wall through time-dependent perfusion of TCO-conjugated molecules into the lumen of the channel. Different cell populations were spatially encapsulated in the channel wall via temporal alteration of cells in the HA-Tz reservoir. The interfacial approach enabled the spatial patterning of vascular cells, including human abdominal aorta endothelial cells, aortic vascular smooth muscle cells, and aortic adventitial fibroblasts, into the hydrogel channels with high viability and proper morphology in the anatomical order found in human arteries. The bioorthogonal platform does not rely on external triggers and represents the first step toward the engineering of functional and implantable arteries.

| S-EPMC6506358 | biostudies-literature

Tyrosine cross-linking reveals interfacial dynamics in adeno-associated viral capsids during infection.

Project description:Viral capsid dynamics are often observed during infectious events such as cell surface attachment, entry and genome release. Structural analysis of adeno-associated virus (AAV), a helper-dependent parvovirus, revealed a cluster of surface-exposed tyrosine residues at the icosahedral two-fold symmetry axis. We exploited the latter observation to carry out selective oxidation of Tyr residues, which yielded cross-linked viral protein (VP) subunit dimers, effectively "stitching" together the AAV capsid two-fold interface. Characterization of different Tyr-to-Phe mutants confirmed that the formation of cross-linked VP dimers is mediated by dityrosine adducts and requires the Tyr704 residue, which crosses over from one neighboring VP subunit to the other. When compared to unmodified capsids, Tyr-cross-linked AAV displayed decreased transduction efficiency in cell culture. Surprisingly, further biochemical and quantitative microscopy studies revealed that restraining the two-fold interface hinders externalization of buried VP N-termini, which contain a phospholipase A2 domain and nuclear localization sequences critical for infection. These adverse effects caused by tyrosine oxidation support the notion that interfacial dynamics at the AAV capsid two-fold symmetry axis play a role in externalization of VP N-termini during infection.

| S-EPMC3376196 | biostudies-literature

Meter-long multiblock copolymer microfibers via interfacial bioorthogonal polymerization.

Project description:High-molecular-weight multiblock copolymers are synthesized as robust polymer fibers via interfacial bioorthogonal polymerization employing the rapid cycloaddition of s-tetrazines with strained trans-cyclooctenes. When cell-adhesive peptide is incorporated in the tetrazine monomer, the resulting protein-mimetic polymer fibers provide guidance cues for cell attachment and elongation.

| S-EPMC4423755 | biostudies-literature

Site-specific cross-linking of proteins to DNA via a new bioorthogonal approach employing oxime ligation.

Project description:DNA-protein cross-links (DPCs) are super-bulky DNA adducts induced by common chemotherapeutic agents, reactive oxygen species, and aldehydes, and also formed endogenously as part of epigenetic regulation. Despite their presence in most cells and tissues, the biological effects of DPCs are poorly understood due to the difficulty of constructing site-specific DNA-protein conjugates. In the present work, a new approach of conjugating proteins to DNA using oxime ligation was used to generate model DPCs structurally analogous to lesions formed in cells. In our approach, proteins and peptides containing an unnatural oxy-Lys amino acid were cross-linked to DNA strands functionalized with 5-formyl-dC or 7-(2-oxoethyl)-7-deaza-dG residues using oxime ligation. The conjugation reaction was site-specific with respect to both protein and DNA, provided excellent reaction yields, and formed stable DPCs amenable to biological evaluation.

| S-EPMC6310614 | biostudies-literature

Living functional hydrogels generated by bioorthogonal cross-linking reactions of azide-modified cells with alkyne-modified polymers.

Project description:To date, many scientists have thoroughly investigated both cells and cellular functions, resulting in the identification of numerous molecular mechanisms underlying the cellular functions. Based on these findings, medical scientists and pharmacologists have developed many technological applications for cells and cellular functions in medicine. How can material scientists utilize cells and cellular functions? Here, we show a concept for utilizing cells and their functions from the viewpoint of materials science. In particular, we develop cell cross-linked living bulk hydrogels by bioorthogonal click cross-linking reactions of azide-modified mammalian cells with alkyne-modified biocompatible polymers. Importantly, we demonstrate the unique functionalities of the living hydrogels, originating from the basic functions of the cells incorporated in the living hydrogels as active cross-linking points. The findings of this study provide a promising route to generating living cell-based next-generation innovative materials, technologies, and medicines.

| S-EPMC5989231 | biostudies-literature

single step cross-linking ChIP-seq

Project description:The chromatin remodeller ATRX interacts with the histone chaperone DAXX, to deposit the histone variant H3.3 at sites of nucleosome turnover. ATRX is known to bind repetitive, heterochromatic regions of the genome including telomeres, ribosomal DNA and pericentric repeats many of which are putative G-quadruplex forming sequences (PQS). At these sites ATRX plays an ancillary role in a wide range of nuclear processes facilitating replication, chromatin modification and transcription. Here, using an improved protocol for chromatin immunoprecipitation, we show that ATRX also binds active regulatory elements in euchromatin. Mutations in ATRX lead to perturbation of gene expression associated with a reduction in chromatin accessibility, histone modification, transcription factor binding and deposition of H3.3 at the sequences to which it normally binds. In erythroid cells where down regulation of a-globin expression is a hallmark of ATR-X syndrome, perturbation of chromatin accessibility and gene expression occurs in only a subset of cells. The stochastic nature of this process suggests that ATRX acts as a general facilitator of cell specific transcriptional and epigenetic programmes, both in heterochromatin and euchromatin.

2022-04-24 | GSE193034 | GEO

two steps cross-linking ChIP-seq

2022-04-24 | GSE193033 | GEO

Single step cross-linking LCL ChIP-seq

2022-04-24 | GSE193311 | GEO

Two steps cross-linking LCL ChIP-seq

2022-04-24 | GSE193310 | GEO