Project description:Assessing relevant molecular differences between human-induced pluripotent stem cells (hiPSCs) and human embryonic stem cells (hESCs) is important, given that such differences may impact their potential therapeutic use. Controversy surrounds recent gene expression studies comparing hiPSCs and hESCs. Here, we present an in-depth quantitative mass spectrometry-based analysis of hESCs, two different hiPSCs and their precursor fibroblast cell lines. Our comparisons confirmed the high similarity of hESCs and hiPSCS at the proteome level as 97.8% of the proteins were found unchanged. Nevertheless, a small group of 58 proteins, mainly related to metabolism, antigen processing and cell adhesion, was found significantly differentially expressed between hiPSCs and hESCs. A comparison of the regulated proteins with previously published transcriptomic studies showed a low overlap, highlighting the emerging notion that differences between both pluripotent cell lines rather reflect experimental conditions than a recurrent molecular signature. See the Data Processing section of the published paper concerning the bioinformatics pipeline used. PMCID: PMC3261715 PMID: 22108792 Mol Syst Biol. 2011 Nov 22;7:550. doi: 10.1038/msb.2011.84. The quantitative proteomes of human-induced pluripotent stem cells and embryonic stem cells. Munoz J, Low TY, Kok YJ, Chin A, Frese CK, Ding V, Choo A, Heck AJ. Biomolecular Mass Spectrometry and Proteomics Group, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Utrecht, The Netherlands.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:It remains controversial whether human induced pluripotent stem cells (hiPSCs) are distinct from human embryonic stem cells (hESCs) in their molecular signatures and differentiation properties. We examined the gene expression and DNA methylation of 49 hiPSC and 10 hESC lines and identified no molecular signatures that distinguished hiPSCs from hESCs. Comparisons of the in vitro directed neural differentiation of 40 hiPSC and four hESC lines showed that most hiPSC clones were comparable to hESCs. However, in seven hiPSC clones, significant amount of undifferentiated cells persisted even after neural differentiation and resulted in teratoma formation when transplantated into mouse brains. These differentiation-defective hiPSC clones were marked by higher expression of several genes, including those expressed from long terminal repeats of human endogenous retroviruses. These data demonstrated that many hiPSC clones are indistinguishable from hESCs, while some defective hiPSC clones need to be eliminated prior to their application for regenerative medicine. Bisulphite converted DNA from 10 hESCs, 49 hiPSCs, 2 hECCs, 6 somatic cells and 3 cancer cell lines were hybridized to the Illumina Infinium 27k Human Methylation Beadchip.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs. Two-condition experiment, KP MSCs vs. 3A6 MSCs.
Project description:Genome wide DNA methylation profiling of normal human embryonic stem cells, induced pluripotent stem cells, and somatic cells. The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 27,000 CpGs in 5 normal hESCs, 15 hiPSCs (vector-containing and vector-free), and 5 somatic cells. Bisulphite converted DNA from the 25 samples were hybridised to the Illumina Infinium 27k Human Methylation Beadchip v1.2