Corbel Catherine, Salaün Josselyne, Belo-Diabangouaya Patricia, Dieterlen-Lièvre Françoise
Institut Cochin, Département d'Hématologie, 123, Boulevard de Port-Royal, 75014 Paris, France.
Dev Biol. 2007 Jan 15;301(2):478-88. doi: 10.1016/j.ydbio.2006.08.069. Epub 2006 Sep 6.
We previously showed that the fetal component of the placenta has a vigorous hematopoietic activity. Whether this organ is an environmental niche where hematopoietic stem cells (HSC) proliferate and become committed to various lineages, or whether it is also a site for HSC emergence, was left open. This issue can be addressed only if the components that will give rise to the placenta are tested prior to vascularization. The fetal part of the placenta forms through the fusion of the allantois and the chorionic plate around the stage of 7 somite pairs. The allantois, a mesodermal rudiment that provides fetal blood vessels to the placenta, was retrieved before fusion. We found in this rudiment expression of CD41, a known marker of early embryonic hematopoietic progenitors. c-Kit encoding a progenitor specific receptor was also expressed. Significantly, as early as the 1-2 somite stage, the allantois yielded erythroid, myeloid and multipotent clonogenic progenitors, when pre-cultured in toto prior to seeding in a semisolid medium. These results provide evidence that the allantois has hematopoietic potential per se. Whether this potential also involves the ability to produce HSC is still to be determined.
我们之前表明，胎盘的胎儿部分具有旺盛的造血活性。该器官究竟是造血干细胞（HSC）增殖并分化为各种谱系的环境龛位，还是也是HSC产生的部位，尚不清楚。只有在血管化之前对形成胎盘的成分进行检测，才能解决这个问题。胎盘的胎儿部分在约7对体节期通过尿囊和绒毛膜板融合形成。尿囊是向胎盘提供胎儿血管的中胚层原基，在融合前被分离出来。我们在这个原基中发现了CD41的表达，CD41是早期胚胎造血祖细胞的已知标志物。编码祖细胞特异性受体的c-Kit也有表达。重要的是，早在1-2体节期，当尿囊在接种到半固体培养基之前进行整体预培养时，就产生了红系、髓系和多能克隆性祖细胞。这些结果提供了证据表明尿囊本身具有造血潜能。这种潜能是否也涉及产生HSC的能力仍有待确定。
