Natural killer cells (NK cells), as an important component of the immune system, play a crucial role in defending against viral infections and anti-tumor responses. Compared to T cells, NK cells show several advantages: first, they can recognize and kill tumor cells without the need for specific antigen stimulation; second, they are not restricted by the expression of major histocompatibility complex (MHC) molecules. The unique properties of NK cells open up a new arena for novel cell-based immunotherapy.
