[Expressions of B-cell-specific monoclonal leukemia virus insert site 1 and human telomerase reverse transcriptase genes in CD34+ cells during ex vivo expansion process].
OBJECTIVE
To investigate the relationship between the expressions of B-cell-specific monoclonal leukemia virus insert site 1 (Bmi1) and human telomerase reverse transcriptase (hTERT) genes and the proliferative capacity of stem cells.


METHODS
Cord blood CD34+ cells were cultured in IMDM medium containing fetal bovine serum, stem cell growth factor, thrombopoietin, and Fms-like tyrosine kinase 3 ligand during a 28-day ex vivo expansion process, while the expansion fold, specific growth rate, and the colony-forming efficiency were monitored. Then the Bmi1 and hTERT mRNA expressions in CD34+ cells were detected by fluorescence quantitative PCR, and the relations between the expressions and the cell proliferative capacity were analyzed.


RESULTS
CD34+ cells expanded (20.1 +/- 3.5) folds during the 28-day culture, while the proportion declined from 95.5% +/- 2.6% before culture to 2.1% +/- 0.4%. Both the specific growth rate and colony-forming efficiency of CD34+ cells declined significantly after 7 days, while the expression levels of Bmi1 and hTERT mRNA in CD34+ cells reached top at 7 days and declined gradually thereafter.


CONCLUSIONS
The expressions of Bmi1 and hTERT genes may have a close relation to the proliferative capacity of CD34+ cells.
State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, PR China.
Jianyun
J
Ge
Haibo
H
Cai
Zheng
Z
Du
Wensong
W
Tan
D018952:Antigens, CD34 / Q000378:metabolism*; D002454:Cell Differentiation; D049109:Cell Proliferation; D002478:Cells, Cultured; D003114:Colony-Forming Units Assay; D003470:Culture Media; D005312:Fetal Blood / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D009000:Monocytes / Q000166:cytology / Q000378:metabolism; D063150:Polycomb Repressive Complex 1 / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D019098:Telomerase / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors
D018952:Antigens, CD34; C069077:BMI1 protein, human; D003470:Culture Media; D012333:RNA, Messenger; D063150:Polycomb Repressive Complex 1; D019098:Telomerase