Cell Phenotypes in human Amniotic Fluid

Abstract

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.

Levels of CD105+ cells increase and cell proliferation decreases during S-phase arrest of amniotic fluid cells in long-term culture

“…The clinically cultured AFCs were positive for mesenchymal cell markers and negative for endothelial, hematopoietic and stem cells markers. This observation may be due to the culture medium and state, which is consistent with the results of a previous study on cell phenotypes ( 21 , 22 ). Several studies have derived hematopoietic stem cells from amniotic fluid and performed screening using flow cytometry prior to establishing the primary culture ( 11 ).…”

p53 Is Active in Human Amniotic Fluid Stem Cells

“…hAFS cells possess all these characteristics and fit perfectly as the ideal stem cell type for therapeutic applications. Most importantly, hAFS cells do not form tumors after transplantation into mice and have properties similar to ES cells [ 13 , 50 ]. P53 is an important tumor suppressor protein and therefore it is very important to clarify whether p53 is functional in hAFS cells before they are used in therapy.…”

“…The population of hAFS cells is highly heterogeneous and they exhibit a high proliferation rate and wide differentiation potential, including differentiation into hematopoietic, neurogenic, osteogenic, chondrogenic, adipogenic, renal, and hepatic lineages [ 11 , 12 ]. Most intriguingly, unlike ES cells, hAFS cells do not produce teratomas when transplanted into nude mice [ 13 ]. This important attribute along with their high genomic stability and epigenetic fidelity makes hAFS cells an ideal candidate for stem cell-based therapeutic applications.…”

Senescence‐induced immunophenotype, gene expression and electrophysiology changes in human amniocytes

“…Our results show that cryopreserved amniocytes express the mesenchymal markers CD29 (98.4%), CD31 (50.7%), CD44 (98.5%), CD49e (99.8%), CD54 (10.3%), CD56 (75.2%), CD73 (97.5%), CD90 (98.4%), CD105 (67.2%), CD146 (88.7%), and do not express CD45 (2.9%), CD117 (4.9%) or CD133 (1.7%) (Figure ; Figure and Table of Supporting Information). The absence of CD45, CD117 and CD133 expression shows that there were no haematopoietic stem/progenitor cells at the time of amniocentesis (16‐20 weeks), when these cells are no longer present in amniotic fluid . The expression of surface markers decreased in senescent amniocytes by up to 82.3% compared to cryopreserved amniocytes, as follows: CD29 54.8%, CD31 1.5%, CD44 22.8%, CD49e 34.5%, CD54 8.5%, CD56 12.7%, CD73 15.2%, CD90 37.7%, CD105 1.7%, CD146 58.3% (see Table of Supporting Information).…”