Method for culturing pluripotent stem cells

A method for culturing induced pluripotent stem cells (iPS cells), the method comprising:

• a) culturing isolated iPS cells that are seeded in a culture medium at a cell density of 4×104 to 6×104 cells/cm3 in a pseudo-microgravity environment to proliferate the iPS cells while maintaining the iPS cells in an undifferentiated state, thereby forming and growing spheroids of the iPS cells;
• b) performing one cycle of disrupting the resulting spheroids by passing the spheroids through a filter having a filter mesh size of 40 to 100 μm to generate disrupted spheroids;
• and
• c) further culturing the disrupted spheroids in the pseudo-microgravity environment, thereby forming and growing spheroids, or repeating the cycle two or more times, wherein the culturing in step a) and c) is performed in the presence of a Rho-associated kinase (ROCK) inhibitor,
• wherein the pseudo-microgravity environment is an environment in which an object is subjected to a gravity corresponding to 1/10 to 1/100 of the earth's gravity in time average, and the pseudo-microgravity environment is obtainable by using a uniaxial rotary bioreactor capable of achieving a pseudo-microgravity environment on earth by canceling out the earth's gravity with stresses caused by rotation, and wherein a culture container having a volume of 5 mL to 100 mL and a rotation speed of 6 to 8.5 rpm are used for culturing the pluripotent stem cells in the pseudo-microgravity environment in step a) and c).