Date Published: July , 2009
Publisher: A.I. Gordeyev
Author(s): D.A. Davydova, E.A. Vorotelyak, Yu.A. Smirnova, R.D. Zinovieva, Yu.A. Romanov, N.V. Kabaeva, V.V. Terskikh, A.V. Vasiliev.
Stem cells capable of long-term proliferation and differentiation into different cell types may be a promising source of cells for regenerative medicine. Recently, much attention has been paid to fetal stem cells, among which are cells from amniotic fluid (AF). We have isolated amniotic stem cells from 3 AF samples. Flow cytometry, RT -PCR and immunohistochemistry have shown that these cells express mesenchymal (CD90, CD73, CD105, CD13, CD29, CD44, and CD146), neural (≤3-tubulin, Nestin, and Pax6), epithelial (keratin 19 and p63) markers and also markers of pluripotency (Oct4, Nanog, and Rex-1). Transplantation of the cells to nude mice does not lead to tumor formation. Thus, putative stem/progenitor cells from AF are capable of long-term proliferation in vitro and the profile of gene expression led us to speculate that they have greater differentiation potential than mesenchymal stem cells and may be useful for cell therapy.
AF has been used in prenatal diagnosis of genetic diseases for more than 70 years . It contains a heterogeneous population of cells, which includes cells from fetal skin, respiratory, digestive, and urinary tracts, as well as cells from the amniotic membrane. Most of these cells are differentiated and have a low proliferative potential [17, 21]. Recent data seem to indicate that AF contains cells which can proliferate for extended periods of time and can differentiate in vitro into different cell types. Based on the fact that these cells express such markers as CD73, CD90, CD105, CD44, and CD29, several researchers consider them as MSCs [20; 16]. Interestingly, cells isolated from AF express neural markers, such as Nestin, ≤3-tubulin, GFAP, NEFH, as well as several markers of ESCs, such as SSEA-4, Oct4, and Nanog [13; 17; 21]. These cells exhibit osteogenic, adipogenic, myogenic and neural differentiation; they can also differentiate into hepatocytes and endothelial cells [20; 7; 21; 6; 12; 25; 26]. Thus, the available data suggest, on the one hand, that cells from AF are intermediate in their differentiation potential (between embryonic and adult stem cells) and, on the other hand, the possibility that AF culture contains several distinct cell types (i.e. population heterogeneity). In order to assess this possibility, a further detailed investigation of the population structure is needed, which implies extensive data on the gene expression profile.
This work was supported by Grant from Russian Foundation for Basic Research (project 09-04-12132-ofi-m).