Amniotic Fluid and Amniotic Membrane Stem Cells: Marker Discovery

Abstract

Amniotic fluid (AF) and amniotic membrane (AM) have been recently characterized as promising sources of stem or progenitor cells. Both not only contain subpopulations with stem cell characteristics resembling to adult stem cells, such as mesenchymal stem cells, but also exhibit some embryonic stem cell properties like (i) expression of pluripotency markers, (ii) high expansion in vitro, or (iii) multilineage differentiation capacity. Recent efforts have been focused on the isolation and the detailed characterization of these stem cell types. However, variations in their phenotype, their heterogeneity described by different groups, and the absence of a single marker expressed only in these cells may prevent the isolation of a pure homogeneous stem cell population from these sources and their potential use of these cells in therapeutic applications. In this paper, we aim to summarize the recent progress in marker discovery for stem cells derived from fetal sources such as AF and AM, using novel methodologies based on transcriptomics, proteomics, or secretome analyses.

High Aminopeptidase N/CD13 Levels Characterize Human Amniotic Mesenchymal Stem Cells and Drive Their Increased Adipogenic Potential in Obese Women

“…Staining for the E-cadherin/CD324 epithelial antigen was very weak in our Ob-and Co-hA-MSC preparations; the coexpression of epithelial, although at a low intensity, and mesenchymal markers on our hA-MSCs was in agreement with previous findings [38,39]. Overall, our results are similar to those reported by Parolini et al [24] and/or Roubelakis [35] regarding the expressed (CD49d, CD90, HLA-ABC, CD13, CD56, CD105, CD166, CD10, CD29, CD44, and CD54) and not expressed (PECAM-1/CD31, HLA-DR, CD14, Prominin-1/CD133, NGFR/CD271, CD34, and CD45) membrane-bound antigens in hA-MSCs. We found that the Ob-hA-MSC immunophenotype is characterized by a significantly higher expression of the APN/CD13 antigen with respect to the Co-hA-MSC phenotype.…”

“…hA-MSCs isolated from normal weight healthy women at delivery have been characterized [24,34,35], but, to our knowledge, the features of hA-MSCs from obese women are largely unknown. In this study, we used flow cytometry to characterize hA-MSCs isolated at delivery from two groups of women: prepregnancy normal weight and prepregnancy severely obese women.…”

In situ vascularization of injectable fibrin/poly(ethylene glycol) hydrogels by human amniotic fluid‐derived stem cells

“…[54] This combination of pro-angiogenic cytokines has a clear effect on the recruitment of endothelial cell types specifically [55] and could mask the effects seen by introducing exogenous vascular cells. [56] In this study, in situ vascularization of subcutaneously injected fibrin/PEG hydrogels was clearly correlated to the presence of a stem cell source, either AFSC or MSC; however, in order to understand the role that AFSC and AFSC-EC play in in vivo vessel formation, further analysis is required. Determining the localization of exogenous cells in both the bulk of the hydrogel and in relation to the formation of dual-positive CD31/αSMA lumen will be critical to assessing the therapeutic potential of AFSC-derived vascularization.…”

Amniotic membrane as a potent source of stem cells and a matrix for engineering heart tissue

“…Roubelakis et al (2012) emphasised that AF and AM stem cells have the immunophenotypic characteristics of both adult mesenchymal stem cells and also embryonic stem cells. Consequently, these cells have been difficult to identify as they do not have markers and phenotypes.…”

“…Consequently, these cells have been difficult to identify as they do not have markers and phenotypes. Roubelakis et al (2012) proposed the use of a novel approach to identify them, based on transcriptomic, proteomic, or secretome analyses [4]. Dobreva et al (2012) studied mice, and suggested the use of periostin as a biomarker of AM [5].…”