Hypoxia enhances proliferation of mouse embryonic stem cell-derived neural stem cells

• Published in: Biotechnology and bioengineering Vol. 106; no. 2; pp. 260 - 270
• Main Authors: Rodrigues, Carlos A.V, Diogo, Maria Margarida, da Silva, Cláudia Lobato, Cabral, Joaquim M.S
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.06.2010; Wiley; Wiley Subscription Services, Inc
• Subjects: Animals; Biological and medical sciences; Biotechnology; Brain; Cell culture; Cell Culture Techniques - methods; Cell Differentiation; Cell Hypoxia - physiology; Cell Line; Embryonic Stem Cells - cytology; Embryonic Stem Cells - metabolism; expansion; Fundamental and applied biological sciences. Psychology; Hypoxia; Mice; monolayer; neural stem cells; Neurons - cytology; Neurons - physiology; Oxygen; Oxygen - metabolism; Rodents; Stem cells; Tissue Engineering - methods; Monolayer; Vertebrata; Mammalia; Mouse; Embryonic cell; neural stem cells; Stem cell; Rodentia; Hypoxia; expansion
• ISSN: 0006-3592; 1097-0290
• DOI: 10.1002/bit.22648

Neural stem (NS) cells can provide a source of material with potential applications for neural drug testing, developmental studies, or novel treatments for neurodegenerative diseases. Herein, the ex vivo expansion of a model system of mouse embryonic stem (mES) cell-derived NS cells was characterized and optimized, cells being cultivated under adherent conditions. Culture was first optimized in terms of initial cell plating density and oxygen concentration, known to strongly influence brain-derived NS cells. To this end, the growth of cells cultured under hypoxic (2%, 5%, and 10% O₂) and normoxic (20% O₂) conditions was compared. The results showed that 2-5% oxygen, without affecting multipotency, led to fold increase values in total cell number about twice higher than observed under 20% oxygen (20-fold vs. 10-fold, respectively) this effect being more pronounced when cells were plated at low density. With an optimal cell density of 10⁴ cells/cm², the maximum growth rates were 1.9 day⁻¹ under hypoxia versus 1.7 day⁻¹ under normoxia. Cell division kinetics analysis by flow cytometry based on PKH67 tracking showed that when cultured in hypoxia, cells are at least one divisional generation ahead compared to normoxia. In terms of cell cycle, a larger population in a quiescent G₀ phase was observed in normoxic conditions. The optimization of NS cell culture performed here represents an important step toward the generation of a large number of neural cells from a reduced initial population, envisaging the potential application of these cells in multiple settings. Biotechnol. Bioeng. 2010;106: 260-270.