CD16 receptor and GM1 colocalize after CD16 engagement by reverse ADCC.

FITC-conjugated anti-CD16 or anti-TfR–treated NK cells were stained with Alexa Fluor 594–conjugated CTB and either directly fixed (A-C and G-I) or incubated with CTB-labeled P815 target cells at 37°C for 3 minutes (D-F and J-L) and then fixed. Cells were analyzed by confocal microscopy. Representative example of isolated NK cells or NK/P815 conjugates from 3 separate experiments are shown. Original magnifications × 600.