Abstract: The present invention relates to a method for producing natural killer cells (hereinafter, referred to as “NK cells”), NK cells produced thereby, and a composition for treating cancers and infectious diseases containing the same. The present invention provides a method for producing NK cells, which maintain high cytotoxicity and cell viability to exhibit high therapeutic effects against cancers and infectious diseases and can be cultured ex vivo at high efficiency and high concentration. In addition, a culture method which maintains cell concentration at a constant level is used for the production of NK cells, and thus the overgrowth of the cells can be prevented so that the cells can be maintained at an optimal state. Particularly, even when the cells are thawed after freezing, the function of the cells is not impaired, and the NK cells can maintain high cell viability and cytotoxicity.

Abstract: The present invention relates to a method for producing natural killer cells (hereinafter, referred to as “NK cells”), NK cells produced thereby, and a composition for treating cancers and infectious diseases containing the same. The present invention provides a method for producing NK cells, which maintain high cytotoxicity and cell viability to exhibit high therapeutic effects against cancers and infectious diseases and can be cultured ex vivo at high efficiency and high concentration. In addition, a culture method which maintains cell concentration at a constant level is used for the production of NK cells, and thus the overgrowth of the cells can be prevented so that the cells can be maintained at an optimal state. Particularly, even when the cells are thawed after freezing, the function of the cells is not impaired, and the NK cells can maintain high cell viability and cytotoxicity.