“Natural-Killer” Cells Display Better Action Against Cancer


Natural killer cells are one of the fundamental parts of our immune system, which can fight against cancer fairly better than the T-cells in our immune system, whose role is most prominent in CAR-T (chimeric antigen receptor T-cell immunotherapy) treatment. The idea is extracted from the philosophy purported by William Colley, that our immune system can be stimulated to fight against cancer. Immunotherapy is now being considered as the most powerful tool in treating cancer.

Recently, a study appearing in the journal “Cell Stem Cell”, reports that ovarian cancer has been fought against quite effectively by modified natural killer cells that were extracted from human-induced iPSCs (Induced Pluripotent Stem Cells). According to Dr. Kauffman, a lead scientist of the NK study, Natural killer cells have a vital advantage over CAR-T which is that they are not required to match up according to a particular patient. Just one batch of these engineered natural killer cells are sufficient for treating thousands of people and these cells do not bring serious toxic side effects. NK cells can be used as an official off-the-shell treatment along with other cancer drugs.

Fate, the main developer of universal NK cell products, with the use of renewable iPSC line, is now in collaboration with Kauffman to move this development into human clinical trials. The CEO and president of Fate Therapeutics claim that this approach can alter the logistics of cell-based immunotherapy of cancer. Hopefully, by the end of this year, Fate’s first product will be moved into the human clinical trials.

Another approach to this concept is by the University of Texas MD Anderson Cancer Center, Houston. The cells from which these NK cells are extracted are not iPSCs but are collected from umbilical cord blood specimens from the Cord Blood Bank of the hospital. NK cells are separated from the cord blood and a CAR is inserted into them that targets the antigen (CD19) appearing in some blood cancers. Moreover, a suicide gene is embedded in case NK cells become toxic; that is when they express CAR in presence of cytokine receptors.

The main difference between the two studies is that NK cells are extracted from human-induced iPSCs in the study by UC San Diego and can be used unlimitedly.   Hence, hopefully, the product, soon to be transferred into a human clinical trial, would bring in better treatment than is proposed by CAR-T alone.