Researchers from Kyoto University (Japan) led by Ken-ichiro Kamei have developed a nanofiber-on-microfiber matrix that could enhance human pluripotent stem cell (hPSC) culture methods and could therefore hold promise in regenerative medicine.
The clinical and industrial potential of hPSCs is currently limited by inefficient culture methods which produce low quantities and quality of cultured cells. This has led to research in to the development of 3D culturing systems which aim to simulate the growth of hPSCs within the human body.
The group has developed a layered nano-on-micro fibrous cellular matrix named “fiber-on-fiber (FF)” matrix on which to seed hPSCs. This consists of a microfiber sheet made of cellulose and polyglycolic acid crosslinked with gelatin nanofibers.
This mesh structure with connected nanofibers mimics the extracellular matrix and facilitates cell growth through strong cell adhesion and the easy exchange of growth factors and supplements from the culture medium to the cells.
The study reported that after four days of culture, over 95% of stem cells adhered to the FF matrix had grown and formed colonies. The results also demonstrate that the FF matrix facilitates hPSC culture with maintenance of their pluripotency and normal chromosomes over two months.
The team also designed a gas-permeable cell culture bag in which to load multiple cell-loaded FF matrices in order to upscale the hPSC culture process. This system reduced the level of stress placed on the cells through a maintained internal environment and generated a higher number of cells compared to conventional culture methods.
The FF matrix therefore offers great promise for culture optimization and the large-scale production of differentiated functional cells in the future.
Liu L, Kamei KI, Yoshioka M et al. Nano-on-micro fibrous extracellular matrices for scalable expansion of human ES/iPS cells. Biomaterials. 124, 47-54 (2017); http://www.kyoto-u.ac.jp/en/research/research_results/2016/170208_3.html; https://www.dddmag.com/article/2017/02/new-nanofiber-matrix-enhances-stem-cell-production.