25/03/2011
http://www.youtube.com/watch?v=HNP1EAYLhOs&feature=related
_______ http://www.cancerfoundation.com_______ Natural Killer Cells are the most aggressive white cells in the immune system. They make up about 5% to 15% of the total lymphocyte circulating population. They target tumor cell and protect against a wide variety of infectious microbes. Natural Killer