Saw this on my FB feed this morning. On rereading I see my title should probably have been Stunning Diversity in NK cell RECEPTORS found, apologies: http://www.niaid.nih.gov/topics/immuneSystem/Pages/naturalKillerCells.aspx So I wasn't sure where they were going with this but it appears the main finding is there are not, as I had assumed, just one kind of NK cell. There are two main kinds, and amongst those there are a HUGE range of variations. My bolds, above and below. Holy NK cells batman, that potentially makes NK cell involvement in CFS/ME that much more complicated...or may simplify things if we learn only certain types of NK cells are involved.