Human umbilical cord blood-derived cells differentiate into hepatocyte-like cells in the Fas-mediated liver injury model.
Human umbilical cord blood (HUCB) contains stem/progenitor cells, which can differentiate into a variety of cell types. In this study, we investigated whether HUCB cells differentiate into hepatocytes in vitro and in vivo. We also examined whether CD34 could be the selection marker of stem cells for hepatocytes. HUCB cells were obtained from normal full-term deliveries, and CD34(+/-) cells were further separated. For in vitro study, HUCB cells were cultured for 4 wk, and expressions of liver-specific genes were examined. For the in vivo study, nonobese diabetic/severe combined immunodeficient mice were subjected to liver injury by a Fas ligand-carried adenoviral vector or only radiated. Mice were treated simultaneously with or without cell transplantation of HUCB, CD34(+), or CD34(-) cells. After 4 wk, human-specific gene/protein expression was examined. In the in vitro study, human liver-specific genes were positive after 7 days of culture. The immunofluorescent study showed positive staining of alpha-fetoprotein, cytokeratin 19, and albumin in round-shaped cells. In the in vivo study, immunohistochemical analysis showed human albumin-positive, hepatocyte-specific antigen-positive cells in mouse livers of the Fas ligand/transplantation group. Fluorescence in situ hybridization analysis using the human Y chromosome also showed positive signals. However, no difference between transplanted cell types was detected. In contrast, immunopositive cells were not detected in the irradiated/transplantation group. The RT-PCR result also showed human hepatocyte-specific gene expressions only in the Fas ligand/transplantation group. HUCB cells differentiated into hepatocyte-like cells in the mouse liver, and liver injury was essential during this process. The differences between CD34(+) and CD34(-) cells were not observed in human hepatocyte-specific expression.
Nonome
Kazunobu
K
Laboratory of Transplantation Immunology, National Research Institute for Child Health and Development, Setagaya-ku, Tokyo 157-8535, Japan.
Li
Xiao-Kang
XK
Takahara
Terumi
T
Kitazawa
Yusuke
Y
Funeshima
Naoko
N
Yata
Yutaka
Y
Xue
Feng
F
Kanayama
Masami
M
Shinno
Eiji
E
Kuwae
Chieko
C
Saito
Shigeru
S
Watanabe
Akiharu
A
Sugiyama
Toshiro
T
D000818:Animals; D018952:Antigens, CD34 / Q000032:analysis; D002454:Cell Differentiation; D002478:Cells, Cultured; D053222:Fas Ligand Protein; D005260:Female; D005312:Fetal Blood / Q000166:cytology*; D005434:Flow Cytometry; D005974:Glutamate-Ammonia Ligase / Q000096:biosynthesis; D022781:Hepatocytes / Q000166:cytology*; D006801:Humans; D007150:Immunohistochemistry; D008099:Liver / Q000293:injuries*; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012709:Serum Albumin / Q000096:biosynthesis; D013234:Stem Cells / Q000378:metabolism; D014168:Transferrin / Q000096:biosynthesis; D048069:Tumor Necrosis Factors / Q000096:biosynthesis; D000509:alpha-Fetoproteins / Q000096:biosynthesis
D018952:Antigens, CD34; C505661:FASLG protein, human; D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D008562:Membrane Glycoproteins; D012709:Serum Albumin; D014168:Transferrin; D048069:Tumor Necrosis Factors; D000509:alpha-Fetoproteins; D005974:Glutamate-Ammonia Ligase