title: Gene expression profiles of human adipose tissue-derived mesenchymal stem cells are modified by cell culture density.
abstract: Previous studies conducted cell expansion ex vivo using low initial plating densities for optimal expansion and subsequent differentiation of mesenchymal stem cells (MSCs). However, MSC populations are heterogeneous and culture conditions can affect the characteristics of MSCs. In this study, differences in gene expression profiles of adipose tissue (AT)-derived MSCs were examined after harvesting cells cultured at different densities. AT-MSCs from three different donors were plated at a density of 200 or 5,000 cells/cm(2). After 7 days in culture, detailed gene expression profiles were investigated using a DNA chip microarray, and subsequently validated using a reverse transcription polymerase chain reaction (RT-PCR) analysis. Gene expression profiles were influenced primarily by the level of cell confluence at harvest. In MSCs harvested at ∼90% confluence, 177 genes were up-regulated and 102 genes down-regulated relative to cells harvested at ∼50% confluence (P<0.05, FC>2). Proliferation-related genes were highly expressed in MSCs harvested at low density, while genes that were highly expressed in MSCs harvested at high density (∼90% confluent) were linked to immunity and defense, cell communication, signal transduction and cell motility. Several cytokine, chemokine and growth factor genes involved in immunosuppression, migration, and reconstitution of damaged tissues were up-regulated in MSCs harvested at high density compared with MSCs harvested at low density. These results imply that cell density at harvest is a critical factor for modulating the specific gene-expression patterns of heterogeneous MSCs.
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Dae Seong
authors.initials: DS
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Myoung Woo
authors.initials: MW
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Keon Hee
authors.initials: KH
authors.lastname: Yoo
authors.affiliation: Department of Laboratory of Cancer and Stem Cell Biology, Plant Engineering Institute, Sejong University, Seoul, Korea.
authors.forename: Tae-Hee
authors.initials: TH
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hye Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: In Keun
authors.initials: IK
authors.lastname: Jang
authors.affiliation: Top Class plastic surgery, Seoul, Korea.
authors.forename: Yong Hoon
authors.initials: YH
authors.lastname: Chun
authors.affiliation: Top Class plastic surgery, Seoul, Korea.
authors.forename: Hyung Joon
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Seung Jo
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Soo Hyun
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Meong Hi
authors.initials: MH
authors.lastname: Son
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hye Lim
authors.initials: HL
authors.lastname: Jung
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ki Woong
authors.initials: KW
authors.lastname: Sung
authors.affiliation: Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hong Hoe
authors.initials: HH
authors.lastname: Koo
mesh_terms: D000273:Adipose Tissue / Q000166:cytology* / Q000378:metabolism*; D000328:Adult; D002452:Cell Count; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D016000:Cluster Analysis; D016207:Cytokines / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D015203:Reproducibility of Results; D059467:Transcriptome; D055815:Young Adult
chemical_list: D016207:Cytokines