Watson A L, Burton G J
Department of Anatomy, University of Cambridge, UK.
Microsc Res Tech. 1998 Sep 1;42(5):351-68. doi: 10.1002/(SICI)1097-0029(19980901)42:5<351::AID-JEMT6>3.0.CO;2-S.
In order to fulfill its many functions as the selective interface between maternal and fetal circulations it is imperative that the human placenta remains intact and in good operational order. That damage of some sort occurs during its short but extremely active life seems inevitable given the dynamic environment in which the placenta exists, and evidence has accumulated that disruption is indeed a regular event. The implications of such damage, one could speculate, may impact on functions such as transport and hormone secretion as well as mutual protection against attack by maternal and fetal immune systems. Consequently, it would seem a theoretical necessity for discontinuities in the placenta surface to be repaired as soon as possible. We have used a combination of ex vivo observation, in vitro modelling, immunohistochemistry and correlative microscopy to provide evidence for a wound response in the placenta and to begin dissecting the detail of how this may operate. Evidence for small lesions caused by fusion and subsequent tearing of the syncytiotrophoblast in vivo, as well as plugging of such wounds by underlying cells is shown. We also identify a putative role for migratory cytotrophoblasts in the healing of larger scale injuries and demonstrate that certain molecules, common to wound repair in other tissues, appear to be involved in placenta repair also. Taken together these results clearly show that the human placenta is capable of a degree of self-maintenance by activating what appears to be an endogenous wound healing mechanism.
为了履行其作为母胎循环之间选择性界面的众多功能，人类胎盘必须保持完整且运转良好。鉴于胎盘所处的动态环境，在其短暂却极其活跃的生命过程中出现某种损伤似乎不可避免，并且已有证据表明这种破坏确实是常有的事。可以推测，这种损伤的影响可能会波及诸如运输和激素分泌等功能，以及母胎免疫系统相互抵御攻击的功能。因此，胎盘表面的连续性尽快修复在理论上似乎是必要的。我们结合了体外观察、体外建模、免疫组织化学和相关显微镜技术，来为胎盘的伤口反应提供证据，并开始剖析其可能的运作细节。展示了体内合体滋养层融合及随后撕裂造成小损伤的证据，以及下层细胞堵塞此类伤口的证据。我们还确定了游走的细胞滋养层在更大规模损伤愈合中的假定作用，并证明其他组织伤口修复中常见的某些分子似乎也参与了胎盘修复。综合这些结果清楚地表明，人类胎盘能够通过激活一种似乎是内源性的伤口愈合机制来进行一定程度的自我维护。
