Natural killer cells, famous for their prowess at wiping out cancer and virus-infected cells, are not always effective, particularly when it comes to fighting tumors. Now, research in mice points to a possible reason: when NK cells “bite off” part of cancer cells’ membranes, they can ingest a serving of protein that renders them useless.
NK cells, also known as large granular lymphocytes, engage tumor cells in a process called trogocytosis, which involves stealing part of their target’s membrane and integrating it into their own. The new study, published today (April 13) in Science Advances, shows in mice with leukemia that this nibble sometimes comes with a side of PD-1, a protein that inhibits NK cell activity, allowing the cancer cell to escape.
When an immune cell such as an NK cell or a T cell encounters PD-1 on the surface of a cancer cell, its activity is subdued. PD-1 ...
