Patent ID: 7972767

Claim:
A method for culturing a mesenchymal stem cell, comprising: a first culture step of culturing a mesenchymal stem cell by suspending mesenchymal stem cells and hematopoietic stem cells in a medium containing blood serum, while maintaining the ratio of mesenchymal stem cells to hematopoietic stem cells within a range of 1:10 to 1:100; and a second culture step of differentiating the mesenchymal stem cell into a biological tissue progenitor cell in a medium containing blood serum at a lower concentration than that in the medium used in the first culture step, wherein the ratio of mesenchymal stem cells to hematopoietic stem cells in a medium is monitored, and a liquid factor for increasing the ratio of mesenchymal stem cells is added if the ratio of hematopoietic stem cells to mesenchymal stem cells is more than 100, and the liquid factor for increasing the ratio of mesenchymal stem cells is made from a mixed solution comprising 1 to 100 ng/mL of PDGF, 1 to 100 ng/mL of bFGF, and 5 to 3000 μg/mL of vitamin C.