Natural killer cellen ofwel NK-cellen zijn grote lymfocyten die behoren tot het niet-specifieke immuunsysteem en die een rol spelen bij celdoding en uitscheiding van cytokinen die worden gebruikt tegen pathogenen.

http://tinyurl.com/2gtqdb

Natural killer (NK) cells have been originally characterized as cytolytic effector lymphocytes present in mouse spleen and human peripheral blood. The “NK” name was originally coined after the NK cell's ability to kill targets cells without requirement for a prior exposure to these targets, in contrast to cytolytic T cells

http://www.ahmf.org/database/natkillercells.html

Natural Killer Cells

http://www.homestead.com/VonHapsburg/NKcells.html

Natural Killer Cells and the Immune System

http://www.liebertonline.com/doi/abs/10.1089/
107999099313523

Lymphocyte Markers and Natural Killer Cell Activity in Fibromyalgia Syndrome: Effects of Low-Dose, Sublingual Use of Human Interferon-alpha