Crucial role of the local micro-environment in fate decision of neonatal rat NG2 progenitors.
OBJECTIVE
The fate choice of neural progenitor cells could be dictated by local cellular environment of the adult CNS. The aim of our study was to investigate the effect of hippocampal tissue on differentiation and maturation of oligodendrocyte NG2 precursor cells.


METHODS
Hippocampal slice culture was established from the brains of 7-day-old rats. NG2 precursor cells, obtained from a 12-day-old mixed primary culture of neonatal rat cerebral hemispheres, were labelled with chloromethyl-fluorescein-diacetete and seeded on the hippocampal slices. After 7-14 days in co-culture, cells were stained with neural markers.


RESULTS
NG2 cells differentiated predominantly into oligodendrocytes, presenting various stages of maturation: progenitors (NG2), pre-oligodendrocytes (O4) and finally mature GalC-positive cells. However, except for a few cells with astrocyte-specific S100b staining, a considerable number of these cells differentiated into neurons: TUJ(+) and even MAP-2(+) cells were frequently observed. Moreover, a certain population of these cells preserved proliferative properties of primary precursor cells, as revealed by Ki67 expression.


CONCLUSIONS
The neuronal micro-environment provided by the culture of hippocampal slices is potent for induction of neurogenesis from oligodendrocyte NG2(+)/PDGFRalpha(+)/CNP(+) progenitor cells and promotes their differentiation not only into macroglia but also into neurons. It also sustains their proliferative capacity. The results indicate the crucial role of the local cellular environment in fate decision of primary NG2(+) multipotent neural progenitor cells, which may affect their behaviour after transplantation into the central nervous system.
Sypecka
J
J
NeuroRepair Department, Medical Research Institute, Polish Academy of Sciences, Warsaw, Poland. joannasy@cmdik.pan.pl
Sarnowska
A
A
Domanska-Janik
K
K
D000818:Animals; D000831:Animals, Newborn; D000941:Antigens / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology; D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D018920:Coculture Techniques; D017077:Culture Media, Conditioned / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology*; D009414:Nerve Growth Factors / Q000378:metabolism; D009474:Neurons / Q000166:cytology*; D009836:Oligodendroglia / Q000166:cytology*; D009924:Organ Culture Techniques; D011509:Proteoglycans / Q000378:metabolism; D051381:Rats; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D000099216:Chondroitin Sulfate Proteoglycan 4
D000941:Antigens; D015415:Biomarkers; D017077:Culture Media, Conditioned; D009414:Nerve Growth Factors; D011509:Proteoglycans; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; D000099216:Chondroitin Sulfate Proteoglycan 4; C579158:S100b protein, rat