RESUMO
A more accurate understanding of the molecular mechanisms and signaling pathways underpinning human mesenchymal stem cell (MSC) plasticity and differentiation properties is pivotal for accomplishing solid and diligent translation of MSC-based experimental therapeutics and clinical trials to broad clinical practice. In addition, this knowledge enables selection of MSC subpopulations with increased differentiation potential and/or use of exogenous factors to boost this potential. Here, we report that CD105 (ENG) is a predictive biomarker of osteogenic potential in two types of MSCs: stem cells from human exfoliated deciduous teeth (SHED) and human adipose-derived stem cells (hASC). We also validate that CD105 can be used to select and enrich for subpopulations of SHED and hASC with higher in vitro osteogenic potential. In addition, we show that hsa-mir-1287 regulates CD105 expression, and propose that fine-tuning hsa-mir-1287 levels could be used to control osteopotential in SHED. These findings provide better discernment of the molecular bases behind MSC osteogenic plasticity and open up new perspectives to leverage osteogenic potential in MSCs by modulation of a specific miRNA.
Assuntos
Endoglina/metabolismo , MicroRNAs/metabolismo , Biomarcadores/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Células Cultivadas , Criança , Endoglina/genética , Citometria de Fluxo , Humanos , Imunofenotipagem , Fator de Crescimento Insulin-Like II/farmacologia , MicroRNAs/genética , Osteogênese/genética , Osteogênese/fisiologia , Reação em Cadeia da Polimerase em Tempo Real , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismoRESUMO
Constraints for the application of MSCs for bone reconstruction include restricted self-renewal and limited cell amounts. iPSC technology presents advantages over MSCs, providing homogeneous cellular populations with prolonged self-renewal and higher plasticity. However, it is unknown if the osteogenic potential of iPSCs differs from that of MSCs and if it depends on the iPSCs originating cellular source. Here, we compared the in vitro osteogenesis between stem cells from human deciduous teeth (SHED) and MSC-like cells from iPSCs from SHED (iPS-SHED) and from human dermal fibroblasts (iPS-FIB). MSC-like cells from iPS-SHED and iPS-FIB displayed fibroblast-like morphology, downregulation of pluripotency markers and upregulation of mesenchymal markers. Comparative in vitro osteogenesis analysis showed higher osteogenic potential in MSC-like cells from iPS-SHED followed by MSC-like cells from iPS-FIB and SHED. CD105 expression, reported to be inversely correlated with osteogenic potential in MSCs, did not display this pattern, considering that SHED presented lower CD105 expression. Higher osteogenic potential of MSC-like cells from iPS-SHED may be due to cellular homogeneity and/or to donor tissue epigenetic memory. Our findings strengthen the rationale for the use of iPSCs in bone bioengineering. Unveiling the molecular basis behind these differences is important for a thorough use of iPSCs in clinical scenarios.
RESUMO
Adipose tissue-derived stem cells (ASCs) association to fat in autologous lipotransfer is promising for a more effective soft tissue reconstruction, and optimization of protocols to isolate ASCs from lipoaspirate fat is much needed. We demonstrated that an increase in adipocyte differentiation is dependent on the number of ASCs. In a sample of 10 donors, we found a higher concentration of nucleated cells in the lower abdomen compared to flank (P = 0.015). In a sample of 6 donors we did not find differences in the cell yield obtained by manual or pump-assisted aspiration (P = 0.56). We suggest that the increase in the number of ASCs in the reinjected fat may enhance the efficiency of newly formed adipose tissue and that the anatomical region from which to harvest fat tissue needs to be considered to optimize the number of ASCs in the harvested tissue. Finally, pump-assisted aspiration can be used without any significant harm to the viability of cells.