BAX and B-cell chronic lymphocytic leukemia: Immunofluorescence analysis of cells stained with anti-active Bax antibodies and Mitotracker Orange, a fluorescent probe that selectively stains mitochondria, showed that the colocalization of active Bax with mitochondria was significantly enhanced in both healthy and CLL cells treated for 20 min with GroPIns compared to untreated cells (Figures 3E, F).