title: Methods for expansion of human embryonic stem cells.
abstract: The manipulation of human embryonic stem cells (hESCs) requires refined skills. Here we introduce both mechanical and enzymatic transfer methods for hESCs depending on experimental purpose. We use the mechanical transfer method for maintenance of hESC lines. Although the method is laborious and time-consuming, the technique permits efficient transfer of undifferentiated hESCs and results in similar clump sizes. We implement the enzymatic transfer method when we need the bulk production of cells for various experiments. The enzyme-treated expansion rapidly produces greater amounts of hESCs within a limited time frame. However, the cell clumps vary in size, and there is a probability that both the differentiated and undifferentiated cells will be transferred. In cases in which there are differentiated colonies, the combination of two methods allows mass production of hESCs by excluding differentiated colonies from passage by manual selection before enzyme treatment.
authors.affiliation: Department of Obstetrics and Gynecology, College of Medicine, Seoul National University, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Korea.
authors.forename: Sun Kyung
authors.initials: SK
authors.lastname: Oh
authors.forename: Hee Sun
authors.initials: HS
authors.lastname: Kim
authors.forename: Yong Bin
authors.initials: YB
authors.lastname: Park
authors.forename: Hye Won
authors.initials: HW
authors.lastname: Seol
authors.forename: Yoon Young
authors.initials: YY
authors.lastname: Kim
authors.forename: Myung Soo
authors.initials: MS
authors.lastname: Cho
authors.forename: Seung Yup
authors.initials: SY
authors.lastname: Ku
authors.forename: Young Min
authors.initials: YM
authors.lastname: Choi
authors.forename: Dong-Wook
authors.initials: DW
authors.lastname: Kim
authors.forename: Shin Yong
authors.initials: SY
authors.lastname: Moon
mesh_terms: D018929:Cell Culture Techniques / Q000379:methods*; D004622:Embryo, Mammalian / Q000166:cytology*; D006801:Humans; D013234:Stem Cells / Q000166:cytology*