Definition:
A natural killer cell is a type of lymphocyte that uses enzymes to destroy cells that have been infected with a virus, or tumor cells.
Cells in our bodies have markers on their surface that identify them as normal to our immune system. Some viruses and cancers remove the identity markers of an infected cell or tumor cell, so that it can slip through the immune system more easily. However, NK cells can recognize that these cells are invaders and will attack them.
Also Known As: NK cell
