Conditions for tumor-free and dopamine neuron-enriched grafts after transplanting human ES cell-derived neural precursor cells.
We have previously demonstrated derivation of neural precursor (NP) cells of a midbrain-type from human embryonic stem (hES) cells to yield an enriched population of dopamine (DA) neurons. These hES-derived NPs can be expanded in vitro through multiple passages without altering their DA neurogenic potential. Here, we studied two aspects of these hES-NP cells that are critical issues in cell therapeutic approaches for Parkinson's disease (PD): cell survival and tumorigenic potential. Neuroepithelial rosettes, a potentially tumorigenic structure, disappeared during hES-NP cell expansion in vitro. Although a minor population of cells positive for Oct3/4, a marker specific for undifferentiated hES cells, persisted in culture during hES-NP cell expansion, they could be completely eliminated by subculturing hES-NPs under differentiation-inducing conditions. Consistently, no tumors/teratomas are formed in rats grafted with multipassaged hES-NPs. However, extensively expanded hES-NP cells easily underwent cell death during differentiation in vitro and after transplantation in vivo. Transgenic expression of Bcl-XL and sonic hedgehog (SHH) completely overcame the cell survival problems without increasing tumor formation. These findings indicate that hES-NP cell expansion in conjunction with Bcl-XL+SHH transgene expression may provide a renewable and safe source of DA neurons for transplantation in PD.
Ko
Ji-Yun
JY
Department of Biochemistry and Molecular Biology, College of Medicine, Hanyang University, Seoul 133-791, Korea.
Lee
Hyun-Seob
HS
Park
Chang-Hwan
CH
Koh
Hyun-Chul
HC
Lee
Yong-Sung
YS
Lee
Sang-Hun
SH
D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D000242:Cyclic AMP / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000187:drug effects; D005260:Female; D005822:Genetic Vectors / Q000235:genetics; D051100:Glial Cell Line-Derived Neurotrophic Factor / Q000494:pharmacology; D053823:Hedgehog Proteins / Q000235:genetics / Q000502:physiology; D006801:Humans; D007150:Immunohistochemistry; D009474:Neurons / Q000166:cytology* / Q000187:drug effects; D016133:Polymerase Chain Reaction; D051381:Rats; D017207:Rats, Sprague-Dawley; D012190:Retroviridae / Q000235:genetics; D051020:bcl-X Protein / Q000235:genetics / Q000502:physiology
D019208:Brain-Derived Neurotrophic Factor; D051100:Glial Cell Line-Derived Neurotrophic Factor; D053823:Hedgehog Proteins; D051020:bcl-X Protein; D000242:Cyclic AMP; D004298:Dopamine