title: Electrophysiology, immunophenotype, and gene expression characterization of senescent and cryopreserved human amniotic fluid stem cells.
abstract: We characterized human amniotic fluid stem cells (AFSC) in senescent cultures (6 weeks) versus cryopreserved cells using whole-cell patch-clamp, immunophenotyping, and differential gene expression profiling for senescence genes. We evidenced five ion current components (outward rectifier, A-type, inward rectifier, and big conductance Ca2+-dependent K+currents, fast voltage-dependent Na+currents). Senescent AFSC showed reduced expression of CD90, CD44, CD133, over 500-fold increase of interferon gamma and telomerase reverse transcriptase genes, increased cycle-dependent kinase 4 inhibitors, p53-binding protein 1, and decreased calreticulin and CD44. HLA-ABC immune expression was similar, and HLA-DR expression very low in both cell types. A subset of cryopreserved AFSC featured large inward rectifier K+currents, voltage-dependent Na+currents, and neural progenitor markers evidenced by immunophenotyping and RT-PCR. In all AFSC, in both culture conditions, at patch rupture the outward currents were very low, and they increased progressively over several minutes upon cytoplasm dialysis with pipette solution.
authors.affiliation: Flow Cytometry and Cell Therapy Laboratory, "N. Simionescu" Institute of Cellular Biology and Pathology, B.P. Hasdeu Str. 8, 050568, Bucharest, Romania.
authors.forename: Florin
authors.initials: F
authors.lastname: Iordache
authors.affiliation: Flow Cytometry and Cell Therapy Laboratory, "N. Simionescu" Institute of Cellular Biology and Pathology, B.P. Hasdeu Str. 8, 050568, Bucharest, Romania.
authors.forename: Andrei
authors.initials: A
authors.lastname: Constantinescu
authors.affiliation: Flow Cytometry and Cell Therapy Laboratory, "N. Simionescu" Institute of Cellular Biology and Pathology, B.P. Hasdeu Str. 8, 050568, Bucharest, Romania.
authors.forename: Eugen
authors.initials: E
authors.lastname: Andrei
authors.affiliation: Department Biophysics and Physiology, Faculty of Biology, University of Bucharest, Splaiul Independentei 91-95, 050095, Bucharest, Romania. bogdan@biologie.kappa.ro.
authors.forename: Bogdan
authors.initials: B
authors.lastname: Amuzescu
authors.affiliation: Department Biophysics and Physiology, Faculty of Biology, University of Bucharest, Splaiul Independentei 91-95, 050095, Bucharest, Romania.
authors.forename: Ferdinand
authors.initials: F
authors.lastname: Halitzchi
authors.affiliation: Genetic Lab SRL, Cpt. Av. N. Drossu Str. 9, 012071, Bucharest, Romania.
authors.forename: Lorand
authors.initials: L
authors.lastname: Savu
authors.affiliation: Flow Cytometry and Cell Therapy Laboratory, "N. Simionescu" Institute of Cellular Biology and Pathology, B.P. Hasdeu Str. 8, 050568, Bucharest, Romania.
authors.forename: Horia
authors.initials: H
authors.lastname: Maniu
mesh_terms: D000653:Amniotic Fluid / Q000166:cytology*; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D015925:Cryopreservation; D055724:Electrophysiological Phenomena; D005786:Gene Expression Regulation / Q000502:physiology*; D006801:Humans; D016130:Immunophenotyping; D013234:Stem Cells / Q000502:physiology*
keywords: Amniotic fluid stem cell; Cryopreserved cell; Differential gene expression; Immunophenotype; Patch-clamp; RT-PCR