Expression of activation markers by CD2+ and CD2- subsets of bovine NK cells. Scatter plots show NKp46 expressing lymphocytes, with CD2 in the x-axis and the indicated marker in the y-axis. PBMCs were analyzed in peripheral blood (A), and isolated NKp46+ cells of the same sample was cultured in the presence of rbIL-2 and analyzed again after 5 (B) and 12 (C) days. Fluorescence settings in the flow cytometer were kept unchanged and verified using secondary controls (not shown). Mean fluorescence intensity (MFI) of the y-axis for each subset is shown for markers showing a continous distribution (i), while quadrant percentages are shown for one marker with a biphasic distribution (ii). Data shown are from one animal representative of eight.