106 research outputs found
Peptide-coated gold nanoparticles for modulation of angiogenesis in vivo
In this work, peptides designed to selectively interact with cellular receptors involved in the regulation of angiogenesis were anchored to oligo-ethylene glycol-capped gold nanoparticles (AuNPs) and used to evaluate the modulation of vascular development using an ex ovo chick chorioallantoic membrane assay. These nanoparticles alter the balance between naturally secreted pro- and antiangiogenic factors, under various biological conditions, without causing toxicity. Exposure of chorioallantoic membranes to AuNPâpeptide activators of angiogenesis accelerated the formation of new arterioles when compared to scrambled peptide-coated nanoparticles. On the other hand, antiangiogenic AuNPâpeptide conjugates were able to selectively inhibit angiogenesis in vivo. We demonstrated that AuNP vectorization is crucial for enhancing the effect of active peptides. Our data showed for the first time the effective control of activation or inhibition of blood vessel formation in chick embryo via AuNP-based formulations suitable for the selective modulation of angiogenesis, which is of paramount importance in applications where promotion of vascular growth is desirable (eg, wound healing) or ought to be contravened, as in cancer development
Nanoscale FasL Organization on DNA Origami to Decipher Apoptosis Signal Activation in Cells
Cell signaling is initiated by characteristic protein patterns in the plasma membrane, but tools to decipher their molecular organization and activation are hitherto lacking. Among the well-known signaling pattern is the death inducing signaling complex with a predicted hexagonal receptor architecture. To probe this architecture, DNA origami-based nanoagents with nanometer precise arrangements of the death receptor ligand FasL are introduced and presented to cells. Mimicking different receptor geometries, these nanoagents act as signaling platforms inducing fastest time-to-death kinetics for hexagonal FasL arrangements with 10 nm inter-molecular spacing. Compared to naturally occurring soluble FasL, this trigger is faster and 100x more efficient. Nanoagents with different spacing, lower FasL number or higher coupling flexibility impede signaling. The results present DNA origami as versatile signaling scaffolds exhibiting unprecedented control over molecular number and geometry. They define molecular benchmarks in apoptosis signal initiation and constitute a new strategy to drive particular cell responses
Nanostructured luminescently labeled nucleic acids
Important and emerging trends at the interface of luminescence, nucleic acids and nanotechnology
are: (i) the conventional luminescence labeling of nucleic acid nanostructures (e.g. DNA tetrahedron);
(ii) the labeling of bulk nucleic acids (e.g. singleâstranded DNA, doubleâstranded DNA) with
nanostructured luminescent labels (e.g. copper nanoclusters); and (iii) the labeling of nucleic acid
nanostructures (e.g. origami DNA) with nanostructured luminescent labels (e.g. silver
nanoclusters). This review surveys recent advances in these three different approaches to the
generation of nanostructured luminescently labeled nucleic acids, and includes both direct and
indirect labeling methods
Selective killing of cells triggered by their mRNA signature in the presence of smart nanoparticles
Potentiating angiogenesis arrest in vivo via laser irradiation of peptide functionalised gold nanoparticles
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