Fig. 6. Exogenously expressed EGFP-Rab27a localizes with WPB-like organelles and not lysosomes in HEK-293 cells. HEK-293 cells were transfected with either EGFP-Rab27a (A-D) or EGFP-Rab27a together with VWF-WT (E-L) and, after 48 hours, they were fixed and processed for immunocytochemistry as described in Materials and Methods. The images shown are composite confocal images of EGFP (Rab27a) (A,E,I and green in D,H,L), LAMP1 (B,F,J and red in D,H,L) and VWF (C,G,K and blue in D,H,L). The same confocal parameters were used to collect the data for both groups (plus and minus VWF-WT). (I-L) An enlarged area from (H) (outlined by the white box). Arrows in (I,K) indicate examples of co-localization between the VWF-positive structures and EGFP, and the arrowheads indicate examples of VWF-positive structures that are negative for EGFP. Scale bars, 10 µm (D,H), 2 µm (L).