Response: Movement of mitochondria during CTL-mediated killing by Ing Swie Goping, and R. Chris Bleackley Blood Volume 113(7):1611-1612 February 12, 2009 ©2009 by American Society of Hematology

Time-lapse imaging of mitochondrial polarization in target cells during cytotoxic lymphocyte-induced death. Time-lapse imaging of mitochondrial polarization in target cells during cytotoxic lymphocyte-induced death. YTS human natural killer (NK) cells stably expressing human grB-EGFP chimeric protein (green) were mixed with human 721.221 B cells stained with the potentiometric dye TMRE (red) and were spotted on a glass coverslip and immediately placed on a heated microscope stage. Images were acquired using a Zeiss Axiovert confocal microsope (Jena, Germany). Images were acquired at 37°C on an LSM 510 laser scanning confocal microscope mounted on a Zeiss Axiovert 100M microscope fitted with a Plan Neofluar oil objective (40×/1.3 NA) and analyzed with LSM5 software (Zeiss). Representative images at indicated time points are shown. Ing Swie Goping, and R. Chris Bleackley Blood 2009;113:1611-1612 ©2009 by American Society of Hematology