Natural Killer cells (NK-cells)
Natural Killer (NK) cells are responsible as the first line-of-defense against any tumor cells or cells which have been infected with virus, as NK cells can instantly recognize such cells and remove them.

Advantages of Natural Killer (NK) Cell Therapeutics
1) NK cells have lower memory (for recognizing previously identified foreign agents) capacity and lower clonal proliferation (multiplying in large number as a single cell type) capacity. Hence NK cells pose much lower risk of cytokine storm compared to T-cell therapy.
2) Upon administration, NK cells stimulate and promote activities of dendritic (antigen-presenting) cells and T-cells, which all together will increase the capacity to fight against the tumor cells.
3) Unlike T-cells which can only destroy tumor cells which express tumor-specific antigens, NK cells can destroy wider variety of tumor cells without any tumor-specific antigens expressed on their surfaces.

Directions of R&D for utilizing NK Cells
Cell therapy through restoration of immune-balance
Under healthy immune-balanced environment, immune-cells and tumor cells remain in balance. However, in a tumor-environment, despite the presence of immune-cells, tumor cells become strongly proliferative and spread through metastasis. In such tumor-environment, administration of high-efficiency NK cells can help the patient’s body to restore immune-balance against the activities of tumor cells.