In vitro and in vivo properties of distinct populations of amniotic fluid mesenchymal progenitor cells

Abstract

Human mesenchymal progenitor cells (MPCs) are considered to be of great promise for use in tissue repair and regenerative medicine. MPCs represent multipotent adherent cells, able to give rise to multiple mesenchymal lineages such as osteoblasts, adipocytes or chondrocytes. Recently, we identified and characterized human second trimester amniotic fluid (AF) as a novel source of MPCs. Herein, we found that early colonies of AF-MPCs consisted of two morphologically distinct adherent cell types, termed as spindle-shaped (SS) and round-shaped (RS). A detailed analysis of these two populations showed that SS-AF-MPCs expressed CD90 antigen in a higher level and exhibited a greater proliferation and differentiation potential. To characterize better the molecular identity of these two populations, we have generated a comparative proteomic map of SS-AF-MPCs and RS-AF-MPCs, identifying 25 differentially expressed proteins and 10 proteins uniquely expressed in RS-AF-MPCs. Furthermore, SS-AF-MPCs exhibited significantly higher migration ability on extracellular matrices, such as fibronectin and laminin in vitro, compared to RS-AF-MPCs and thus we further evaluated SS-AF-MPCs for potential use as therapeutic tools in vivo. Therefore, we tested whether GFP-lentiviral transduced SS-AF-MPCs retained their stem cell identity, proliferation and differentiation potential. GFP-SS-AF-MPCs were then successfully delivered into immunosuppressed mice, distributed in different tissues and survived longterm in vivo. In summary, these results demonstrated that AF-MPCs consisted of at least two different MPC populations. In addition, SS-AF-MPCs, isolated based on their colony morphology and CD90 expression, represented the only MPC population that can be expanded easily in culture and used as an efficient tool for future in vivo therapeutic applications.

Comparative proteomic analysis of two distinct stem-cell populations from human amniotic fluid

“…12 Similar to our results, Roubelakis MG et al isolated two types of AF stem cells that differed in their morphology, proliferative potential and expression of CD90, OCT-4, SOX2 and NANOG. 5 The differences between the two types of stem cells found in that study are only partially similar with the two types of HASCs we have been characterizing. Whereas distinct proliferative potentials were found in both studies, our current study failed to detect differences in CD90, OCT-4, SOX2, and NANOG expressions between fHASCs and sHASCs, although the two types of AF cells did differ in their respective expressions of KLF4, CD117, and SSEA4 ( Fig.…”

“…In 2011, a study reported by Roubelakis et al described the characterization of two morphologically distinct AF mesenchymal progenitor cell-types. 5 Although both populations expressed the typical markers of mesenchymal stem cells, they differed in shape, proliferation ability, and expression of the CD90 marker. Proteomic analysis of those two AF cell lines revealed twenty-five proteins that were differentially expressed as well as ten proteins unique to a single cell type.…”

Molecular and Phenotypic Characterization of Human Amniotic Fluid-Derived Cells: A Morphological and Proteomic Approach

“…Among the proteins detected, 9 corresponded to epithelial cells, whereas 12 proteins were reported to be expressed in fibroblasts [12]. [14], 25 proteins were found to be differentially expressed in SS-AF-MPCs as compared to RS-AF-MPCs, reflecting their high proliferative rate, differentiation potency, lentiviral This article has been peer-reviewed and accepted for publication, but has yet to undergo copyediting and proof correction. The final published version may differ from this proof.…”

Cytokinesis-Block Micronucleus Assay Adapted for Analyzing Genomic Instability of Human Mesenchymal Stem Cells

“…A number of authors have shown that human stem cells remain morphologically and genetically stable after in vitro culture [8][9][10][11][12][13][14][15][16][17]. However, one of the main problems that can arise in stem cell lines isolated from different sources is the possibility of genetic instability during cell expansion [18,19].…”