Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3-4
pubmed:dateCreated
2006-6-8
pubmed:abstractText
Human embryonic stem (hES) cells require cooperative interactions with each other for their survival. Previously, the size of hES cell clumps has been reported to be an important factor in determining their viability during routine serial passage. However, the effects of seeding density of the hES cell clumps per se have not yet been investigated. Therefore, this study attempted to compare the level of spontaneous differentiation of hES colonies passaged at two different split ratios (1:3 and 1:8) of a single confluent well of a six-well dish. After 7 d of in vitro culture following serial passage, hES colonies were assigned into three grades according to their degree of spontaneous differentiation: (1) Grade A, which was completely or mostly undifferentiated; (2) grade B, which was partially differentiated; and (3) grade C, which was mostly differentiated. Assessment of the degree of spontaneous differentiation was based on morphological observations under bright-field and phase-contrast microscopy, as well as on immunocytochemical staining for the pluripotency markers SSEA-3 and TRA-1-81. We observed that, at a split ratio of 1:3, the percentages of grade A, B, and C colonies were 89.5, 8.8, and 1.7%, respectively. This was significantly different from the corresponding values of 52.7, 31.3, and 16.0%, respectively, obtained at a split ratio of 1:8. Hence, our results indicated that a lower passage density led to a higher degree of spontaneous differentiation of hES colonies.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
1071-2690
pubmed:author
pubmed:issnType
Print
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
54-7
pubmed:meshHeading
pubmed:articleTitle
Human embryonic stem cell (hES) colonies display a higher degree of spontaneous differentiation when passaged at lower densities.
pubmed:affiliation
Stem Cell Laboratory, Faculty of Dentistry, National University of Singapore, 5 Lower Kent Ridge Road, 119074 Singapore.
pubmed:publicationType
Journal Article