Yeup YOONDirector, Mogam Biotechnology Research Inst.

NK cells are known as the most powerful effector cells for the first-defense line of immunity. Especially in the case of hematopoietic stem cell transplantation (HSCT), the alloreactivity of the NK cell demonstrated to contribute the improved outcomes significantly. From the in vivo functionality, the adoptive transfer of NK cells has been applied for many kinds of cancers. The most difficult hurdle of NK cell therapy has been the limitation on the expansion and activation of NK cell ex vivo.

We established a novel method for the expansion and activation of the NK cells from healthy volunteers and prepared for clinical application under GMP guidance. The ex vivo expanded NK cells demonstrate the high level of purity, identified by CD3-, CD16+ and CD56+ immunophenotype. They also showed NKG2D+, NKp44+ and NKp46+ patterns after 14 days manipulation. The cytotoxicity of expanded cells was also confirmed against K562 and a variety of tumor cell lines as well. This novel method simplifies NK cell expansion and enables the preparation of highly purified effective NK cells for cancer therapy.