Novel Sources of Fetal Stem Cells: Where do they Fit on the Developmental Continuum?

Abstract

The recent isolation of fetal stem cells from several sources either at the early stages of development or during the later trimesters of gestation, sharing similar growth kinetics and expressing pluripotency markers, provides strong support to the notion that these cells may be biologically closer to embryonic stem cells, actually representing intermediates between embryonic stem cells and adult mesenchymal stem cells, regarding proliferation rates and plasticity features, and thus able to confer an advantage over postnatal mesenchymal stem cells derived from conventional adult sources such as bone marrow. This conclusion has been strengthened by the different pattern of growth potential between the two stage-specific types of sources, as assessed by transcriptomic and proteomic analysis. A series of recent studies regarding the numerous novel features of fetal stem cells has reignited our interest in the field of stem-cell biology and in the possibilities for the eventual repair of damaged organs and the generation of in vitro tissues on biomimetic scaffolds for transplantation. These studies, employing elegant approaches and novel technologies, have provided new insights regarding the nature and the potential of fetal stem cells derived from placenta, amniotic fluid, amnion or umbilical cord. In this update, we highlight the major progression that has occurred in fetal stem-cell biology and discuss the most important areas for future investigation in the field of regenerative medicine.

Mesenchymal stem cells from amnion and amniotic fluid in the bovine

“…The lack of expression of COL2A1 might be led to the culture conditions employed in this study as chondrogenic differentiation of MSCs in monolayer culture appears to be dose dependent and time dependent in relation to the bioactive factors used (Bosnakovski et al 2004(Bosnakovski et al , 2005. Bovine AF-MSCs represent a heterogeneous population originating from the three germ layers, whose cells share an epithelial origin and are derived from either the developing embryo or the inner surface of the amniotic membrane (Pappa & Anagnou 2009). This was evident during the primary culture (at P0), when fibroblastic-like or flatter and circular cells were recognized.…”

Transplantation of umbilical cord–derived mesenchymal stem cells as a novel strategy to protect the central nervous system: technical aspects, preclinical studies, and clinical perspectives

“…The hUC contains many stem cell types, including MSCs (4,23). Cord blood has been demonstrated to be a viable clinical alternative to BM transplantation for 20 years, and allogeneic cord blood banks now run in accordance with international standards of safety, quality control, and graft conservation (24,25).…”

“…A rich source of stem and progenitor cells that is, however, free of these ethical issues, is the human umbilical cord (hUC, ref. 4).…”

Amniotic fluid stem cell-based models to study the effects of gene mutations and toxicants on male germ cell formation

“…Furthermore, monoclonal human AFS cell lines have been reported to maintain genome stability during expansion and do not induce tumour formation in severe combined immunodeficient mice. 41,44,46,47,49,61,62 To analyse the genetic mechanisms of sperm cell development, it is of the highest relevance to use stem cell-based models, which allow the investigation of the consequences of a specific genetic aberration. 63,64 One approach would be to use stem cells with natural occurring genetic aberrations, which are of relevance for human pathological phenotypes associated with infertility.…”