Similarities and differences between bmLECs, bmVECs and bmAECs. A/ BmLECs could not be distinguished from bmVECs or bmAECs by cellular morphology alone. Actin staining of the three cells using Rhodamine-phalloidin showed actin filaments arranged in dense bands around the cell periphery and actin stress fibers extending throughout the cytoplasm. B/ Despite being similar in morphology, RT-PCR analysis showed bmLECs and not bmVECs or bmAECs expressed Prox-1 and VEGR-3; bmAECs and not bmVECs expressed neuropilin-1. All cells expressed Tie-2 and Tie-1. C/ By immunofluorescence, bmLECs stained positive for podoplanin, Prox-1, and LYVE-1.