title: Proteome Changes during Transition from Human Embryonic to Vascular Progenitor Cells.
abstract: Human embryonic stem cells (hESCs) are promising in regenerative medicine (RM) due to their differentiation plasticity and proliferation potential. However, a major challenge in RM is the generation of a vascular system to support nutrient flow to newly synthesized tissues. Here we refined an existing method to generate tight vessels by differentiating hESCs in CD34(+) vascular progenitor cells using chemically defined media and growth conditions. We selectively purified these cells from CD34(-) outgrowth populations also formed. To analyze these differentiation processes, we compared the proteomes of the hESCs with those of the CD34(+) and CD34(-) populations using high resolution mass spectrometry, label-free quantification, and multivariate analysis. Eighteen protein markers validate the differentiated phenotypes in immunological assays; nine of these were also detected by proteomics and show statistically significant differential abundance. Another 225 proteins show differential abundance between the three cell types. Sixty-three of these have known functions in CD34(+) and CD34(-) cells. CD34(+) cells synthesize proteins implicated in endothelial cell differentiation and smooth muscle formation, which support the bipotent phenotype of these progenitor cells. CD34(-) cells are more heterogeneous synthesizing muscular/osteogenic/chondrogenic/adipogenic lineage markers. The remaining >150 differentially abundant proteins in CD34(+) or CD34(-) cells raise testable hypotheses for future studies to probe vascular morphogenesis.
authors.affiliation: Department of Protein structure and Proteomics Facility, Institute of Molecular Biology and Biotechnology - FORTH , 70013 Iraklio, Crete, Greece.|Department of Biology, University of Crete , 70013 Iraklio, Crete, Greece.
authors.forename: Konstantinos C
authors.initials: KC
authors.lastname: Tsolis
authors.affiliation: Division of Biomedical Research, Institute of Molecular Biology and Biotechnology - FORTH , 45110 Ioaninna, Greece.
authors.forename: Eleni
authors.initials: E
authors.lastname: Bagli
authors.affiliation: Department of Protein structure and Proteomics Facility, Institute of Molecular Biology and Biotechnology - FORTH , 70013 Iraklio, Crete, Greece.
authors.forename: Katerina
authors.initials: K
authors.lastname: Kanaki
authors.affiliation: Division of Biomedical Research, Institute of Molecular Biology and Biotechnology - FORTH , 45110 Ioaninna, Greece.
authors.forename: Sofia
authors.initials: S
authors.lastname: Zografou
authors.affiliation: SYBIOMA, KU Leuven facility for Systems Biology Based Mass Spectrometry , B-3000 Leuven Belgium.
authors.forename: Sebastien
authors.initials: S
authors.lastname: Carpentier
authors.affiliation: School of Electronic and Computer Engineering, Technical University of Crete , 73100 Chania, Greece.
authors.forename: Ekaterini S
authors.initials: ES
authors.lastname: Bei
authors.affiliation: Division of Biomedical Research, Institute of Molecular Biology and Biotechnology - FORTH , 45110 Ioaninna, Greece.|Laboratory of Biological Chemistry, Medical School, University of Ioannina , 45110 Ioannina, Greece.
authors.forename: Savvas
authors.initials: S
authors.lastname: Christoforidis
authors.affiliation: School of Electronic and Computer Engineering, Technical University of Crete , 73100 Chania, Greece.
authors.forename: Michalis
authors.initials: M
authors.lastname: Zervakis
authors.affiliation: Division of Biomedical Research, Institute of Molecular Biology and Biotechnology - FORTH , 45110 Ioaninna, Greece.|School of Biosciences, College of Life and Environmental Sciences, University of Birmingham , Edgbaston, Birmingham B15 2TT, U.K.
authors.forename: Carol
authors.initials: C
authors.lastname: Murphy
authors.affiliation: Division of Biomedical Research, Institute of Molecular Biology and Biotechnology - FORTH , 45110 Ioaninna, Greece.|Laboratory of Biological Chemistry, Medical School, University of Ioannina , 45110 Ioannina, Greece.|School of Biosciences, College of Life and Environmental Sciences, University of Birmingham , Edgbaston, Birmingham B15 2TT, U.K.
authors.forename: Theodore
authors.initials: T
authors.lastname: Fotsis
authors.affiliation: Department of Protein structure and Proteomics Facility, Institute of Molecular Biology and Biotechnology - FORTH , 70013 Iraklio, Crete, Greece.|Department of Biology, University of Crete , 70013 Iraklio, Crete, Greece.|SYBIOMA, KU Leuven facility for Systems Biology Based Mass Spectrometry , B-3000 Leuven Belgium.
authors.forename: Anastassios
authors.initials: A
authors.lastname: Economou
mesh_terms: D018952:Antigens, CD34; D002454:Cell Differentiation; D002478:Cells, Cultured; D003470:Culture Media / Q000494:pharmacology; D042783:Endothelial Cells / Q000737:chemistry / Q000166:cytology; D000066449:Human Embryonic Stem Cells / Q000737:chemistry / Q000166:cytology*; D006801:Humans; D013058:Mass Spectrometry; D009131:Muscle, Smooth, Vascular / Q000737:chemistry / Q000166:cytology; D020543:Proteome / Q000032:analysis*; D013234:Stem Cells / Q000737:chemistry / Q000166:cytology*
chemical_list: D018952:Antigens, CD34; D003470:Culture Media; D020543:Proteome
keywords: CD34+; PLS; angiogenesis; comparative proteomics; endothelial progenitor cells; hESCs; multivariate analysis; vascular cell differentiation