Trophoblast stem cells - methods of isolation, histological and cellular characteristic, and their possible applications in human and animal models

The placenta is a part of feto-maternal unit that develops from the maternal decidua basalis and fetal-derived trophoblast cells. The regulation of its early development is extremely intricate, albeit the elusive trophoblast stem cells (TSCs) are thought to give rise to the fetal part of the placenta. TSCs may be isolated in both animal and human models. In detail, TSCs can be efficiently obtained from the early conceptus tissues – blastocysts or early placental tissue. The isolation of murine TSCs pave the way for analyses of human trophoblast cell lineages. Both human and animal stem cells retain similar characteristic properties – the ability for unrestricted self-renewal and differentiation into all trophoblast cell lines. Nevertheless, there are some essential differences across the various species which are especially pronounced when pertaining to their distinct optimal cell culture requirements. Moreover, there are several crucial discrepancies in the stemness marker gene transcription profiles between human and murine TSCs models. In vitro TSC models can be adapted to the elucidation of the pathophysiology of various reproductive complications. For instance, their properties may illustrate the conditions observed during the implantation or simulate the state of abnormal placentation. Observations gained from the experimental studies could potentially explain the cause of some cases of infertility, preeclampsia, and fetal growth abnormalities.

Running title: Update on the trophoblast stem cells