Chemokine stimulation decreased D6 colocalization with Rab proteins. Confocal analysis of CHO-K1/D6 cells stained for D6 expression with EEA1 (A), Rab4 (B), Rab11 (C), and Tf (D) in presence or absence of CCL3L1 (100 nM, 30 minutes). For each panel, the first column represents nuclear staining (DAPI, light blue) merged to the DIC image, and the second column shows D6 (red) and Rabs/Tf (green) expression. Inserts show magnifications of the boxed area. (E) Quantification of D6 colocalization volume with the indicated endosomal marker in basal conditions (□) and after CCL3L1 addition (100 nM, 30 minutes; ■). Results are means plus or minus SEM from the analysis of at least 30 different images, obtained in 3 independent experiments, performed as described in “Immunofluorescence and confocal microscopic analysis.” Asterisks indicate significant differences between cells incubated with CCL3L1 and untreated cells (*P < .05; **P < .01).