Two days instead of a week
Stem cells are a kind of factory, they are constantly dividing to create new cells. Implantation of stem cells into organs can replace damaged tissues with new ones. The engineering of cellular implants, which allows stem cells to be transplanted into damaged areas in the form of thin sheets consisting only of cells, completely eliminates the risk of immune rejection caused by external factors and promotes tissue regeneration.
A joint research team from Pohan University of Science and Technology (POSTECH) and Pohang Semyung Christianity Hospital, South Korea, recently managed to reduce the assembly time of such stem cell sheets by almost three times.
Nanotopography of poly-N-isopropylacrylamide (PNIPAAm), which dramatically changes its texture depending on temperature, allows the collection of cell layers consisting of mesenchymal stem cells derived from human bone marrow. Considering that the assembly of stem cells into sheets using existing methods takes an average of one week, two days is the shortest "harvest" time in the entire history of observations.
The research team focused on PNIPAAm, a polymer that either combines with water or repels it depending on temperature. In previous studies, PNIPAAm was used as a coating platform for assembling sheets from cells, but the range of applications was small due to the limited types of cells that can be glued into sheets. In 2019, the research team developed a technology for simple adjustment of the texture of a three-dimensional PNIPAAm coating and was able to collect various types of cells already.
The new study focused on turning stem cells, which are effectively involved in tissue regeneration, into thin sheets in a shorter time to increase the direct utility of the technology. To do this, the group used an isotropic pattern with nanopores measuring 400 nanometers on the surface of a three-dimensional three-dimensional PNIPAAm.
As a result, it was possible not only to accelerate the formation and maturation of mesenchymal stem cells obtained from human bone marrow, but also with the help of nanopores to increase the roughness of PNIPAAm on the surface of the platform by reducing the temperature to room temperature, which facilitated the detachment of cell sheets. This, in turn, made it possible to quickly obtain sheets from stem cells.
Thus, nanopores on the surface of the platform helped to reduce the time for creating sheets from mature stem cells from 5-7 days to two. In the future, the group will work on the possibility of using stem sheets directly in patients.
Article A.Choi et al. Rapid harvesting of stem cell sheets by thermoresponsive bulk poly(N-isopropylacrylamide) (PNIPAAm) nanotopography is published in the journal Biomaterials Science.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on POSTECH materials: Stem Cell Sheets Harvested in Just Two Days.