The immune system contains a number of cell types, such as [[NK cells]] and [[cytotoxic T cell|killer T cells]] that have the capability to destroy other cells that have become infected with viruses or have become cancerous. [[Immunotherapy]] utilizes these natural defenses against tumor cells.
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The immune system contains a number of cell types, such as [[NK cells]] and [[cytotoxic T cell|killer T cells]] that have the capability to destroy other cells that have become infected with viruses or have become cancerous. [[Immunotherapy]] involves the enhancement or potentiation of these natural defenses against tumor cells.