Genetically engineered fibers of the protein spidroin — the construction material for spider webs — are a ideal matrix (substrate or frame) for cultivating heart tissue cells, Moscow Institute of Physics and Technology (MIPT) researchers have found, as noted in an open-access article in the journal PLOS ONE.
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Researchers led by Professor Konstantin Agladze, who heads the Laboratory of the Biophysics of Excitable Systems at MIPT, have been cultivating tissues that contract and conduct excitation waves, from cells called cardiomyocytes.
They decided to explore using synthetic electrospun fibers of spidroin as a matrix. They’re light, five times stronger than steel, twice more elastic than nylon, and are capable of stretching a third of their length. Which is why they are currently used as a substrate to grow implants like bones, tendons and cartilages, as well as dressings.
But could they are also function for soft tissues, such as the heart? Agladze decided to find out. His team seeded isolated neonatal rat cardiomyocytes on fiber matrices. Using a microscope and fluorescent markers, the researchers monitored the growth of the cells and tested their contractibility and the ability to conduct electric impulses, which are the main features of normal cardiac tissue. Within three to five days a layer of cells formed on the substrate. They were able to contract synchronously and conduct electrical impulses just like the tissue of a living heart would.
“Cardiac tissue cells successfully adhere to the substrate of recombinant spidroin,” Agladze says. “They grow forming layers and are fully functional, which means they can contract coordinately.”