Yano Kiichiro, Gale Daniel, Massberg Steffen, Cheruvu Pavan K, Monahan-Earley Rita, Morgan Ellen S, Haig David, von Andrian Ulrich H, Dvorak Ann M, Aird William C
Center for Vascular Biology Research and Division of Molecular and Vascular Medicine, Beth Israel Deaconess Medical Center, RW-663, 330 Brookline Ave, Department of Pathology, Harvard Medical School, Boston, MA 02215, USA.
Blood. 2007 Jan 15;109(2):613-5. doi: 10.1182/blood-2006-05-026401. Epub 2006 Sep 21.
Mammalian endothelial cells (ECs) display marked phenotypic heterogeneity. Little is known about the evolutionary mechanisms underlying EC heterogeneity. The last common ancestor of hagfish and gnathostomes was also the last common ancestor of all extant vertebrates, which lived some time more than 500 million years ago. Features of ECs that are shared between hagfish and gnathostomes can be inferred to have already been present in this ancestral vertebrate. The goal of this study was to determine whether the hagfish endothelium displays phenotypic heterogeneity. Electron microscopy of the aorta, dermis, heart, and liver revealed ultrastructural heterogeneity of the endothelium. Immunofluorescent studies demonstrated marked differences in lectin binding between vascular beds. Intravital microscopy of the dermis revealed histamine-induced adhesion of leukocytes in capillaries and postcapillary venules, but no such adhesion in arterioles. Together, these data suggest that structural, molecular, and functional heterogeneity of the endothelium evolved as an early feature of this cell lineage.
哺乳动物内皮细胞（ECs）表现出显著的表型异质性。关于内皮细胞异质性背后的进化机制，我们知之甚少。盲鳗和有颌类动物的最后一个共同祖先也是所有现存脊椎动物的最后一个共同祖先，它生活在5亿多年前的某个时期。可以推断，盲鳗和有颌类动物共有的内皮细胞特征在这个原始脊椎动物中就已经存在。本研究的目的是确定盲鳗内皮是否表现出表型异质性。对主动脉、真皮、心脏和肝脏进行电子显微镜检查，发现内皮存在超微结构异质性。免疫荧光研究表明，不同血管床之间的凝集素结合存在显著差异。对真皮进行活体显微镜检查发现，组胺可诱导白细胞在毛细血管和毛细血管后微静脉中黏附，但在小动脉中未观察到这种黏附现象。这些数据共同表明，内皮细胞的结构、分子和功能异质性是该细胞谱系的早期特征。
