title: Effect of cell-density on in-vitro dopaminergic differentiation of mesencephalic precursor cells.
abstract: Neural precursor cells isolated from early embryonic mesencephalon are in-vitro expanded and differentiated toward dopamine neurons. However, conditions for controlled conversion of the precursors into dopamine neurons largely remained to be determined. We here examined the effects of plating cell density and duration of in-vitro cell expansion on the precursors-derived dopamine differentiation. The yield of dopamine neurons from cultured mesencephalic precursors was greater when the cells were initially plated at higher density. Soluble factors secreted from the precursors appeared to be responsible for the cell density effect. We further demonstrated that the dopamine differentiation potential of the precursors was lost after a long-term cell expansion. Therefore, in order to attain high percentage of dopamine neuron population in mesencephalic precursor cultures, cultures need to be seeded at high cell density and to be expanded for a short period of time.
authors.affiliation: Department of Biochemistry, College of Medicine, Hanyang University, Seoul 133-791, Korea.
authors.forename: Ji-Yun
authors.initials: JY
authors.lastname: Ko
authors.forename: Ji-Yeon
authors.initials: JY
authors.lastname: Lee
authors.forename: Chang-Hwan
authors.initials: CH
authors.lastname: Park
authors.forename: Sang-Hun
authors.initials: SH
authors.lastname: Lee
mesh_terms: D000818:Animals; D015153:Blotting, Western / Q000379:methods; D001921:Brain / Q000166:cytology / Q000187:drug effects / Q000201:enzymology; D002452:Cell Count / Q000379:methods; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods; D017077:Culture Media, Conditioned / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D004622:Embryo, Mammalian; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007150:Immunohistochemistry / Q000379:methods; D008636:Mesencephalon / Q000166:cytology*; D009281:Naphthalenes / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism*; D010082:Oxepins / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013234:Stem Cells / Q000502:physiology*; D013997:Time Factors; D014404:Tubulin / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
chemical_list: C461941:1-phenyl-1,4-epoxy-1H,4H-naphtho(1,8-de)(1,2)dioxepin; D017077:Culture Media, Conditioned; D005904:Glial Fibrillary Acidic Protein; D009281:Naphthalenes; D010082:Oxepins; D012333:RNA, Messenger; D014404:Tubulin; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine