Professor Shin Heung-soo, Department of Bioengineering, created artificial tissue that can spontaneously differentiate into bone and cartilage, and showed that the artificial tissue can be regenerated to the level similar to the actual tissue. The artificial tissue called stem cell spheroids with diameters of hundreds of millimeters induced regeneration of artificial bilayer tissue through spontaneous cellular assembly.
Research has been actively conducted to obtain cells to be transplanted into damaged tissue by controlling the proliferation or differentiation of undifferentiated stem cells. However, no one had found a way to ensure the long-term survival of transplanted cells by engineering the complex osteochondral microenvironment and inducing their simultaneous regeneration in vivo into bone and cartilage tissue, before this research.
Professor Shin and his team delivered growth factors for chondrogenesis and osteogenesis into composite spheroids composed of stem cells, increasing differentiation efficiency by more than two times, to facilitate the spontaneous differentiation into bone and cartilage without external factors. Through this process, the team managed to construct the bilayer structure of the actual osteochondral tissue. In addition, the stem cell spheroids retain their characteristic as bone or cartilage tissue for 21 days of long-term culture. The researchers implanted these spheroids into a rabbit model with the trochlear groove osteochondral defect, and found that bone was regenerated in the implanted area more than two times than in the control groups and cartilage was also formed 2.5 times more than International Cartilage Repair Society (ICRS) score.
Professor Shin said, “We controlled the differentiation of stem cell spheroids, allowing them to create a structure similar to the actual osteochondral tissue through spontaneous cellular assembly. This research will give the clue to not only research on transplantation in the damaged area but also development of organoids that can be used for studies on drug efficacy and toxicity.”
The research was conducted with the support of the Basic Research Program in Science and Engineering and the Original Technology Research Program by the Ministry of Science and ICT and the National Research Foundation of Korea. The findings were published online in the scientific journal Advanced Science on November 21st.
