Immunolocalization of FVIII and VWF in CHO and ECs by confocal microscopy. CHO cells transfected with an expression vector for FVIII (E) or for VWF (F), HCMECs (A-D), and HUVECs (G-H) were costained for VWF (in red) and FVIII (in green). Nuclei are counterstained with DAPI (blue) in panels D through H. Cells were analyzed by a Multiphoton Zeiss CLSM510 META NLO confocal microscope equipped with LSM 510 acquisition software, Version 4.2.SP1 (Carl Zeiss). All images are taken with a Plan-Apochromat 63×/1.4 oil DIC objective at 2× zoom (B-H) or without zoom (A). Images in panels B through D and G and H are 3D reconstructions. Top panels are (A) representative merge image of FVIII and of VWF costaining in HCMECs (bar, 10 μm); (B-C) staining of FVIII and of VWF, respectively, in HCMECs; (D) merged image of panels B and C. White arrows point out some colocalizations of FVIII and VWF (bars, 5μm). Bottom panels are CHO-FVIII (E), CHO-VWF (F), and HUVECs (G-H) costained for FVIII and VWF (bars, 5 μm).