Search Results
Cellular responses to beating hydrogels to investigate mechanotransduction
2019, Chandorkar, Yashoda, Castro Nava, Arturo, Schweizerhof, Sjören, Van Dongen, Marcel, Haraszti, Tamás, Köhler, Jens, Zhang, Hang, Windoffer, Reinhard, Mourran, Ahmed, Möller, Martin, De Laporte, Laura
Cells feel the forces exerted on them by the surrounding extracellular matrix (ECM) environment and respond to them. While many cell fate processes are dictated by these forces, which are highly synchronized in space and time, abnormal force transduction is implicated in the progression of many diseases (muscular dystrophy, cancer). However, material platforms that enable transient, cyclic forces in vitro to recreate an in vivo-like scenario remain a challenge. Here, we report a hydrogel system that rapidly beats (actuates) with spatio-temporal control using a near infra-red light trigger. Small, user-defined mechanical forces (~nN) are exerted on cells growing on the hydrogel surface at frequencies up to 10 Hz, revealing insights into the effect of actuation on cell migration and the kinetics of reversible nuclear translocation of the mechanosensor protein myocardin related transcription factor A, depending on the actuation amplitude, duration and frequency.
Gold-DNA nanosunflowers for efficient gene silencing with controllable transformation
2019, Huo, Shuaidong, Gong, Ningqiang, Jiang, Ying, Chen, Fei, Guo, Hongbo, Gan, Yaling, Wang, Zhisen, Herrmann, Andreas, Liang, Xing-Jie
The development of an efficient delivery system for enhanced and controlled gene interference–based therapeutics is still facing great challenges. Fortunately, the flourishing field of nanotechnology provides more effective strategies for nucleic acid delivery. Here, the triplex-forming oligonucleotide sequence and its complementary strand were used to mediate self-assembly of ultrasmall gold nanoparticles. The obtained sunflower-like nanostructures exhibited strong near-infrared (NIR) absorption and photothermal conversion ability. Upon NIR irradiation, the large-sized nanostructure could disassemble and generate ultrasmall nanoparticles modified with c-myc oncogene silencing sequence, which could directly target the cell nucleus. Moreover, the controlled gene silencing effect could be realized by synergistically controlling the preincubation time with the self-assembled nanostructure (in vitro and in vivo) and NIR irradiation time point. This study provides a new approach for constructing more efficient and tailorable nanocarriers for gene interference applications