Breakthrough in cell reprogramming
Doctors have successfully grown new vessels inside the mouse body for the first time
For the first time, an international team of physicians was able to grow new vessels in the body of a living rodent thanks to a unique nano-patch that delivers sets of instructions from "DNA bricks", nucleotides to the right corners of the tissue and makes them grow, according to an article published in the journal Nature Materials (Chiappini et al., Biodegradable silicon nanoneedles delivering nucleic acids intracellularly induced localized in vivo neovascularization – VM).
"This is a real quantum leap compared to all existing technologies for delivering genetic information to cells and tissues. By gaining direct access to the cytoplasm of cells, we were able to achieve an incredibly high efficiency of cell reprogramming. This opens the way for truly personalized medicine. All this is due to small structures a thousand times thinner than a human hair," said Ennio Tasciotti from the Methodist Research Institute in Houston (USA).
The heart of the invention of Taschotti and his colleagues are special microscopic needles made of the finest filaments and particles of porous silicon. From the inside, they look like a soft sponge that can absorb and accumulate a sufficiently large amount of liquid, the role of which in the experiment was played by short fragments of RNA and DNA.
In microphotographs from the article Prototype 'nanoneedles' generate new blood vessels in mice, posted on the website of another team of authors of the work, employees of Imperial College London, at the top there is a human cell (which one, neither here nor below is indicated) lying on a plate with nanoeedles; in the bottom picture it can be seen how orange nanoeedles deliver DNA to the blue-colored nuclei of VM cells.These fragments, getting into the cells, make them temporarily or permanently "forget" their current role and perform the tasks assigned to them by scientists.
For example, in the case of experimental mice, Tashotti's group used such patches to insert the VEGF-165 gene into the muscle cells on the rodent's back, which forced them to stimulate the growth of new vessels.
Within a week after the patch was attached to the back, dozens of new capillaries began to appear in its thickness, and this effect persisted throughout the next two weeks of the experiment. The set of nano-needles itself disappeared on the second day after their attachment due to the gradual dissolution of silicon, but during this time they have already managed to deliver genetic "instructions" to 80% of the cells on the animal's back without causing inflammation and other problems.
Such patches, as scientists emphasize, can be used not only to restore blood vessels, but also for a lot of other medical purposes. For example, these nanoeedles can be used to replace damaged nerve cells, repair burnt skin, remove ugly scars and "glue" implanted organs with the rest of the body.
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