Light-activated RNA interference in human embryonic stem cells

Abstract

a b s t r a c tWe describe a near infrared (NIR) light-activated gene silencing method in undifferentiated human embryonic stem cell (hESC) using a plasmonic hollow gold nanoshell (HGN) as the siRNA carrier. Our modular biotin-streptavidin coupling strategy enables positively charged TAT-peptide to coat oligonucleotides-saturated nanoparticles as a stable colloid formation. TAT-peptide coated nanoparticles with dense siRNA loading show efficient penetration into a wide variety of hESC cell lines. The siRNA is freed from the nanoparticles and delivered to the cytosol by femtosecond pulses of NIR light with potentially exquisite spatial and temporal control. The effectiveness of this approach is shown by targeting GFP and Oct4 genes in undifferentiated hESC (H9). The accelerated expression of differentiation markers for all three germ layers resulting from Oct4 knockdown confirms that this method has no detectable adverse effects that limit the range of differentiation. This biocompatible and NIR laseractivated patterning method makes possible single cell resolution of siRNA delivery for diverse studies in stem cell biology, tissue engineering and regenerative medicine.Published by Elsevier Ltd.

Generation of Integration‐Free Induced Neurons Using Graphene Oxide‐Polyethylenimine

“…For this procedure to be clinically safe, transgenes must not be integrated into the genomes of target cells. Hence, although gene transfer techniques using viral vectors have been developed, these techniques may integrate transgenes into the genome, and hence cannot be used clinically.…”

Hyperthermia using nanoparticles – Promises and pitfalls

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Light‐Patterned RNA Interference of 3D‐Cultured Human Embryonic Stem Cells

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