title: Chromosomal instability and telomere shortening in long-term culture of hematopoietic stem cells: insights from a cell culture model of RPS14 haploinsufficiency.
abstract: The fate of cultivated primary hematopoietic stem cells (HSCs) with respect to genetic instability and telomere attrition has not yet been described in great detail. Thus, knowledge of the genetic constitution of HSCs is important when interpreting results of HSCs in culture. While establishing a cell culture model for myelodysplastic syndrome with a deletion in 5q by performing RPS14 knockdown, we found surprising data that may be of importance for any CD34+ cell culture experiments. We performed cytogenetic analyses and telomere length measurement on transduced CD34+ cells and untransduced control cells to observe the effects of long-term culturing. Initially, CD34+ cells had a normal median telomere length of about 12 kb and showed no signs of chromosomal instability. During follow-up, the median telomere length seemed to decrease and, simultaneously, increased chromosomal instability could be observed - in modified and control cells. One culture showed a clonal monosomy 7 - independent of prior RPS14 knockdown. During further culturing, it seemed that the telomeres re-elongated, and chromosomes stabilized, while TERT expression was not elevated. In summary, irrespective of our results of RPS14 knockdown in the long-term culture of CD34+ cells, it becomes clear that cell culture artefacts inducing telomere shortening and chromosomal instability have to be taken into account and regular cytogenetic analyses should always be performed.
authors.affiliation: Institute of Cell and Molecular Pathology, Hannover Medical School, Hannover, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Thomay
authors.forename: A
authors.initials: A
authors.lastname: Schienke
authors.forename: B
authors.initials: B
authors.lastname: Vajen
authors.forename: U
authors.initials: U
authors.lastname: Modlich
authors.forename: A
authors.initials: A
authors.lastname: Schambach
authors.forename: W
authors.initials: W
authors.lastname: Hofmann
authors.forename: B
authors.initials: B
authors.lastname: Schlegelberger
authors.forename: G
authors.initials: G
authors.lastname: Göhring
mesh_terms: D018952:Antigens, CD34 / Q000032:analysis; D016477:Artifacts; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D043171:Chromosomal Instability / Q000235:genetics*; D002872:Chromosome Deletion; D002895:Chromosomes, Human, Pair 5 / Q000235:genetics* / Q000648:ultrastructure; D003114:Colony-Forming Units Assay; D004260:DNA Repair; D005312:Fetal Blood / Q000166:cytology; D017930:Genes, Reporter; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000648:ultrastructure*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D020014:K562 Cells; D007621:Karyotyping; D009190:Myelodysplastic Syndromes / Q000235:genetics / Q000473:pathology; D016133:Polymerase Chain Reaction; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D012269:Ribosomal Proteins / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics* / Q000502:physiology; D019098:Telomerase / Q000378:metabolism; D059506:Telomere Shortening / Q000235:genetics*; D014161:Transduction, Genetic
chemical_list: D018952:Antigens, CD34; D034741:RNA, Small Interfering; C526722:RPS14 protein, human; D012269:Ribosomal Proteins; C509186:TERT protein, human; D019098:Telomerase