Nishikawa S I, Nishikawa S, Kawamoto H, Yoshida H, Kizumoto M, Kataoka H, Katsura Y
Department of Molecular Genetics, Faculty of Medicine, Kyoto University, Japan.
Immunity. 1998 Jun;8(6):761-9. doi: 10.1016/s1074-7613(00)80581-6.
We have investigated the lymphohematopoietic potentials of endothelial cells (EC) and hematopoietic cells (HPC) sorted from embryos. Expression of VE-cadherin, CD45, and Ter119 was used to distinguish EC (VE-cadherin+CD45-Ter119-) from HPC (VE-cadherin-CD45+). Thus defined, EC population takes up acetylated LDL and coexpresses CD31, Flk1, and CD34. In E9.5 embryos, EC from yolk sac (YS) and the embryo proper generate blood cells, including lymphocytes. Thus, lymphohematopoietic EC do exist in the embryo, and they are generated both in YS and the embryo proper. On the other hand, HPC with lymphopoietic potency appear first in the embryo proper. These findings implicate involvement of multiple environmental cues for acquiring lymphopoietic competency during differentiation of HPC.
我们研究了从胚胎中分离出的内皮细胞（EC）和造血细胞（HPC）的淋巴细胞生成和造血潜能。通过血管内皮钙黏蛋白（VE-cadherin）、CD45和Ter119的表达来区分EC（VE-cadherin+CD45-Ter119-）和HPC（VE-cadherin-CD45+）。如此定义的EC群体摄取乙酰化低密度脂蛋白（LDL）并共表达CD31、Flk1和CD34。在E9.5胚胎中，卵黄囊（YS）和胚胎本身的EC可生成血细胞，包括淋巴细胞。因此，胚胎中确实存在具有淋巴细胞生成能力的造血内皮细胞，它们在YS和胚胎本身中均可生成。另一方面，具有淋巴细胞生成潜能的HPC首先出现在胚胎本身中。这些发现表明，在HPC分化过程中，多种环境信号参与了获得淋巴细胞生成能力的过程。
