Fig. 2: Two mobile subpopulations of CD47 coexist on the cell surface and their proportion evolves with apoptosis.

a–c CD47 was detected with an anti-CD47 antibody (B6H12) labeled with A647 and imaged by TIRF microscopy during 120 s at 33 Hz. a CD47 was visualized on non-treated (control) or UVB-irradiated HeLa cells. Brightfield images (BF) were used to differentiate spread cells from apoptotic cells (left panels). CD47 localizations were compiled to reconstruct the image (middle panel). Mean Jump Distances (MJDs) were calculated for individual CD47 trajectories and each trajectory was colored according to its MJD value (color scale on the right side). The dotted line in the lower right image delimits the spread cell from the apoptotic cell presenting a blebbing phenotype. Scale bar, 10 μm on BF images, 5 µm on CD47 images. b Representative MJD distributions extracted from the acquisition of the cells shown in (a). Two classes of CD47 mobility were determined according to their MJD as annotated on the histogram obtained on a viable control cell. c Views of CD47 localization from 250 frames tracks showing CD47 sequestered on structures putatively assigned to microvilli (white arrow) and microvesicles (yellow arrows). Scale bar, 5 μm.