[Research on in vitro differentiation of human umbilical cord blood-derived CD34+ cells into hepatocyte-like cells].
OBJECTIVE
To observe the effect of cytokines and combinations in the inducement of human umbilical cord blood-derived CD34+ cells into hepatocyte-like cells.


METHODS
The mononuclear cells (MNCs) were derived by density gradient centrifugation and the CD34+ cells were separated from MNCs. The human umbilical cord blood-derived CD34+ cells were cultivated through 49 different combinations of cytokines including leukemia inhibitor factor (LIF), oncostatin M, bFGF, aFGF, hepatocyte growth factor, EGF and stem cell factor for 28 days, and the concentrations of the cytokines were 10, 10, 10, 10, 20, 20 and 50 ng/mL, respectively. The mRNAs of cytokeratin 19 (CK-19), CK-18, glutamine synthetase (GS), human albumin (ALB) and alpha-fetoprotein (AFP) were detected every seven days. The ALB secretion ability, detoxification ability and hepatic synthesis ability of the induced cells were detected by immunofluorescence assay, indocyanine green (ICG) and periodic acid-schiff assay, respectively. The fresh umbilical cord blood-derived CD34+ cells were detected at the same time as a control.


RESULTS
The mRNAs of CK-19, CK-18 and GS could be transcribed in all the induced cells, but the transcription of the mRNAs of ALB and AFP which was the special mark of mature hepatocyte and liver stem cell, respectively, was not found. All the mRNAs could not be found in freshly isolated umbilical cord blood-derived CD34+ cells. All the cells induced in vitro could not release ALB, and not help the detoxification of ICG which was the fundamental function of mature liver cells. These results were the same in the control group. The hepatic synthesis ability of all the induced cells increased by comparison to the fresh ones.


CONCLUSIONS
Though some mRNAs of proteins which are transcribed in hepatocytes can be found in the induced cells, umbilical cord blood-derived CD34+ cells could not be transdifferentiated into hepatocyte-like cells through cytokines in vitro.
Chen
Yiqi
Y
State Key Lab of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, P.R.China.
Cai
Haibo
H
Tan
Wensong
W
D018952:Antigens, CD34; D018929:Cell Culture Techniques / Q000379:methods; D002454:Cell Differentiation; D002469:Cell Separation / Q000379:methods; D002478:Cells, Cultured; D005312:Fetal Blood / Q000166:cytology*; D022781:Hepatocytes / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D009000:Monocytes / Q000166:cytology*; D012333:RNA, Messenger / Q000235:genetics; D013234:Stem Cells
D018952:Antigens, CD34; D012333:RNA, Messenger