Natural killer cells (natural killer cell, NK) is an important immune cells in the body, not only related to anti-tumor, anti-virus infection and immunity, and in some cases, to participate in allergic reactions and autoimmune disease.

       In recent years, more and more studies have revealed the biological characteristics of NK cells and their ability to recognize cancer cells. There has also been a breakthrough in immunotherapy to stimulate the immune system to fight cancer. But immunotherapy based on NK cells has not been studied much.

         Researchers from the karolinska institute tested immunotherapy based on NK cells in 16 patients with drug-resistant leukemia. These patients were treated with activated NK cells obtained from the associated donor. Six of the patients responded to the treatment, and some even went away completely, becoming asymptomatic. Five of the six patients had improved to the status of a treatable stem cell transplant, which they were unable to receive before receiving NK cell immunotherapy. Three of them have survived for more than three years and one for more than five years. At the same time, NK cell therapy did not produce a serious side effect.

         These results bring new approaches to new clinical research, and the study offers new hope for further improvements in the optimization of next-generation NK cell immunotherapy.