Endothelial cells derived from human umbilical veins were first successfully cultured in vitro in 1973. Weibel-Palade bodies and the von Willebrand factor antigen were used as morphological, immunohistochemical, and functional markers to unequivocally identify the cells. These landmark studies helped initiate the growth of modern vascular biology.
Ralph L. Nachman, Eric A. Jaffe
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