|Title||CD133 (Prominin) negative human neural stem cells are clonogenic and tripotent.|
|Publication Type||Journal Article|
|Year of Publication||2009|
|Authors||Sun Y, Kong W, Falk A, Hu J, Zhou L, Pollard SM, Smith A|
|Keywords||Animals, Antigens, CD, Antigens, CD15, Cell Line, Cell Proliferation, Clone Cells, Flow Cytometry, G0 Phase, G1 Phase, Gene Expression, Glycoproteins, Humans, Immunohistochemistry, Ki-67 Antigen, Neurons, Peptides, Rats, Reverse Transcriptase Polymerase Chain Reaction, RNA, Messenger, Stem Cells, Totipotent Stem Cells|
BACKGROUND: CD133 (Prominin) is widely used as a marker for the identification and isolation of neural precursor cells from normal brain or tumor tissue. However, the assumption that CD133 is expressed constitutively in neural precursor cells has not been examined.
METHODOLOGY/PRINCIPAL FINDINGS: In this study, we demonstrate that CD133 and a second marker CD15 are expressed heterogeneously in uniformly undifferentiated human neural stem (NS) cell cultures. After fractionation by flow cytometry, clonogenic tripotent cells are found in populations negative or positive for either marker. We further show that CD133 is down-regulated at the mRNA level in cells lacking CD133 immunoreactivity. Cell cycle profiling reveals that CD133 negative cells largely reside in G1/G0, while CD133 positive cells are predominantly in S, G2, or M phase. A similar pattern is apparent in mouse NS cell lines. Compared to mouse NS cells, however, human NS cell cultures harbour an increased proportion of CD133 negative cells and display a longer doubling time. This may in part reflect a sub-population of slow- or non-cycling cells amongst human NS cells because we find that around 5% of cells do not take up BrdU over a 14-day labelling period. Non-proliferating NS cells remain undifferentiated and at least some of them are capable of re-entry into the cell cycle and subsequent continuous expansion.
CONCLUSIONS: The finding that a significant fraction of clonogenic neural stem cells lack the established markers CD133 and CD15, and that some of these cells may be dormant or slow-cycling, has implications for approaches to identify and isolate neural stem cells and brain cancer stem cells. Our data also suggest the possibility that CD133 may be specifically down-regulated during G0/G1, and this should be considered when this marker is used to identify and isolate other tissue and cancer stem cells.
|Alternate Journal||PLoS ONE|
|PubMed Central ID||PMC2676510|
|Grant List||G0800784 / / Medical Research Council / United Kingdom |
G1001028 / / Medical Research Council / United Kingdom
G9806702 / / Medical Research Council / United Kingdom
/ / Biotechnology and Biological Sciences Research Council / United Kingdom
/ / Medical Research Council / United Kingdom