造血干祖细胞(HSPC)是通过胚胎发生过程中内皮到造血的过渡过程而衍生自称为血源性内皮细胞(HEC)的特定内皮细胞亚群。最近,随着多种单细胞技术和先进的遗传谱系追踪技术的使用,即,“TIF”方法结合转录组,免疫表型和功能/命运分析,关于胚胎血管床HSPCs出现的细胞和分子进化,已经获得了大量新的见解。在这次审查中,我们关注富集标记的最新进展,功能特征,发展道路,分子控制,以及桥接胚胎血管和造血系统的关键中间细胞群的胚胎位点相关性,即HECs和前造血干细胞,一些HECs的直接后代,小鼠和人类胚胎。具体来说,使用转录和蛋白质水平的表达分析,特别是有效的功能测定,我们认为Kit表达的开始是在HEC阶段,这在以前是有争议的。
Hematopoietic stem progenitor cells (HSPCs) are derived from a specialized subset of endothelial cells named hemogenic endothelial cells (HECs) via a process of endothelial-to-hematopoietic transition during embryogenesis. Recently, with the usage of multiple single-cell technologies and advanced genetic lineage tracing techniques, namely, \"TIF\" approaches that combining transcriptome, immunophenotype and function/fate analyses, massive new insights have been achieved regarding the cellular and molecular evolution underlying the emergence of HSPCs from embryonic vascular beds. In this review, we focus on the most recent advances in the enrichment markers, functional characteristics, developmental paths, molecular controls, and the embryonic site-relevance of the key intermediate cell populations bridging embryonic vascular and hematopoietic systems, namely HECs and pre-hematopoietic stem cells, the immediate progenies of some HECs, in mouse and human embryos. Specifically, using expression analyses at both transcriptional and protein levels and especially efficient functional assays, we propose that the onset of Kit expression is at the HEC stage, which has previously been controversial.