Localization of PLD isoforms in HUVECs. (A) Subcellular localization of endogenous PLD1 in resting HUVECs. Fixed and permeabilized HUVECs were stained with antibodies against PLD1 and anti-human LAMP3/CD63 (top panels) or anti-human VWF antibodies (middle panels). In the bottom panels, the anti-PLD1 staining is compared with the distribution of exogenously expressed tPA-GFP. (B) Colocalization of GFP-tagged PLD2 and syntaxin 4 in resting HUVECs. Bars represent 10 μm.