Generation of iPSC lines from primary human amniotic fluid cells.

By means of retroviral transduction using the four Yamanaka-factors OCT4, SOX2, KLF4 and c-MYC primary human amniotic fluid cells (AFCs) were reprogrammed into several iPSC lines. Pluripotency was confirmed both in vitro and in vivo. A comparative transcriptome analysis of the AF-derived iPSC line 41 and the human embryonic stem cell lines (H1 and H9) revealed a Pearson correlation of 0.

Multi-omic profiles of human non-alcoholic fatty liver disease tissue highlight heterogenic phenotypes.

Non-alcoholic fatty liver disease (NAFLD) is a consequence of sedentary life style and high fat diets with an estimated prevalence of about 30% in western countries. It is associated with insulin resistance, obesity, glucose intolerance and drug toxicity. Additionally, polymorphisms within, e.

Association between in vivo bone formation and ex vivo migratory capacity of human bone marrow stromal cells.

Introduction: There is a clinical need for developing systemic transplantation protocols for use of human skeletal stem cells (also known bone marrow stromal stem cells) (hBMSC) in tissue regeneration. In systemic transplantation studies, only a limited number of hBMSC home to injured tissues suggesting that only a subpopulation of hBMSC possesses "homing" capacity. Thus, we tested the hypothesis that a subpopulation of hBMSC defined by ability to form heterotopic bone in vivo, is capable of homing to injured bone.

HIF1α modulates cell fate reprogramming through early glycolytic shift and upregulation of PDK1-3 and PKM2.

Reprogramming somatic cells to a pluripotent state drastically reconfigures the cellular anabolic requirements, thus potentially inducing cancer-like metabolic transformation. Accordingly, we and others previously showed that somatic mitochondria and bioenergetics are extensively remodeled upon derivation of induced pluripotent stem cells (iPSCs), as the cells transit from oxidative to glycolytic metabolism. In the attempt to identify possible regulatory mechanisms underlying this metabolic restructuring, we investigated the contributing role of hypoxia-inducible factor one alpha (HIF1α), a master regulator of energy metabolism, in the induction and maintenance of pluripotency.

Comparative molecular portraits of human unfertilized oocytes and primordial germ cells at 10 weeks of gestation.

Primordial germ cells (PGCs) are precursors of gametes and share several features in common with pluripotent stem cells, such as alkaline phosphatase activity and the expression of pluripotency-associated genes such as OCT4 and NANOG. PGCs are able to differentiate into oocytes and spermatogonia and establish totipotency after fertilization. However, our knowledge of human germ cell development is still fragmentary.

Molecular signature of human amniotic fluid stem cells during fetal development.

Mid-gestation c-KIT(+) amniotic fluid stem cells (AFSC) have an intermediate phenotype between embryonic and adult stem cells and are easy to reprogram to pluripotency. We previously showed that 1st trimester AFSC can be reprogrammed to functional pluripotency in a transgene-free approach. Despite both parental populations sharing a common phenotype, expressing CD29, CD44, CD73, CD90, CD105, SSEA4 and OCT4, 2nd trimester AFSC, contrary to 1st trimester cells, do not express NANOG, SSEA3, TRA-1-60 and TRA-1-81, and have slower growth kinetics.

Valproic acid confers functional pluripotency to human amniotic fluid stem cells in a transgene-free approach.

Induced pluripotent stem cells (iPSCs) with potential for therapeutic applications can be derived from somatic cells via ectopic expression of a set of limited and defined transcription factors. However, due to risks of random integration of the reprogramming transgenes into the host genome, the low efficiency of the process, and the potential risk of virally induced tumorigenicity, alternative methods have been developed to generate pluripotent cells using nonintegrating systems, albeit with limited success. Here, we show that c-KIT+ human first-trimester amniotic fluid stem cells (AFSCs) can be fully reprogrammed to pluripotency without ectopic factors, by culture on Matrigel in human embryonic stem cell (hESC) medium supplemented with the histone deacetylase inhibitor (HDACi) valproic acid (VPA).

Preparation of mouse embryonic fibroblast cells suitable for culturing human embryonic and induced pluripotent stem cells.

In general, human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs)(1) can be cultured under variable conditions. However, it is not easy to establish an effective system for culturing these cells. Since the culture conditions can influence gene expression that confers pluripotency in hESCs and hiPSCs, the optimization and standardization of the culture method is crucial.

Human induced pluripotent stem cells--from mechanisms to clinical applications.

Human pluripotent stem cells hold great promise for basic research and regenerative medicine due to their inherent property to propagate infinitely, while maintaining the potential to differentiate into any given cell type of the human body. Since the first derivation in 1998, pluripotent human embryonic stem cells (ESCs) have been studied intensively, and although these cells provoke ethical and immune rejection concerns, translation of human ESC research into the clinics has been initiated. The generation of embryonic stem cell-like human induced pluripotent stem cells (iPSCs) from somatic cells by virus-mediated overexpression of distinct sets of reprogramming factors (OCT4, SOX2, KLF4, and c-MYC, or OCT4, SOX2, NANOG, and LIN28) in 2007 has opened up further opportunities in the field.

The cytotoxic and immunogenic hurdles associated with non-viral mRNA-mediated reprogramming of human fibroblasts.

Delivery of reprogramming factor-encoding mRNAs by means of lipofection in somatic cells is a desirable method for deriving integration-free iPSCs. However, the lack of reproducibility implies there are major hurdles to overcome before this protocol becomes universally accepted. This study demonstrates the functionality of our in-house synthesized mRNAs expressing the reprogramming factors (OCT4, SOX2, KLF4, c-MYC) within the nucleus of human fibroblasts.