BACKGROUND:In the research and application of neural stem cells,cell culture and passage are key links,which directly affect the quality of cells and experimental results.It is of great significance to find the most suitable digestive enzymes that can maintain the biological characteristics of embryonic mouse spinal cord neural stem cells and enhance their passage efficiency.OBJECTIVE:To explore the most suitable digestive enzyme for passage of neural stem cells from the spinal cord of embryonic mice.METHODS:Microscopic dissection was used to isolate and extract spinal cord tissue from E14 d embryonic mice,which was cultured in DMEM/F12 serum-free medium containing epidermal growth factor,basic fibroblast growth factor,and B27.After spherulation,Nestin and Sox2 immunofluorescence identification was performed.During neural stem cell passage and culture,single-cell suspensions were prepared using trypsin,papain,and TrypLETM Express enzyme digestion combined with blow molding.The cell dispersion and spheroidization were observed,and passage 3 cells were stained with propidium iodide to detect cell death.Cell proliferation was detected by counting the total number of cells.Immunofluorescence staining,western blot assay and RT-PCR were used to detect the expression of Olig2,Tuj1,GFAP,and NeuN at the protein and mRNA levels and to identify cell differentiation.RESULTS AND CONCLUSION:After 72 hours of culture,E14 d embryonic mouse spinal cord tissue cells could form suspended neurospheres,which could be passaged after 5-7 days.Compared with trypsin and papain,TrypLETM Express enzyme combined with blow beating method was used for passage.The cell dispersion rate was high,the activity was good,and more NeuN-and Tuj1-positive neurons differentiated.This study optimized the culture and passaging process of neural stem cells,laying a foundation for further research on stem cell transplantation therapy for spinal cord diseases.

BACKGROUND:In the research and application of neural stem cells,cell culture and passage are key links,which directly affect the quality of cells and experimental results.It is of great significance to find the most suitable digestive enzymes that can maintain the biological characteristics of embryonic mouse spinal cord neural stem cells and enhance their passage efficiency.OBJECTIVE:To explore the most suitable digestive enzyme for passage of neural stem cells from the spinal cord of embryonic mice.METHODS:Microscopic dissection was used to isolate and extract spinal cord tissue from E14 d embryonic mice,which was cultured in DMEM/F12 serum-free medium containing epidermal growth factor,basic fibroblast growth factor,and B27.After spherulation,Nestin and Sox2 immunofluorescence identification was performed.During neural stem cell passage and culture,single-cell suspensions were prepared using trypsin,papain,and TrypLETM Express enzyme digestion combined with blow molding.The cell dispersion and spheroidization were observed,and passage 3 cells were stained with propidium iodide to detect cell death.Cell proliferation was detected by counting the total number of cells.Immunofluorescence staining,western blot assay and RT-PCR were used to detect the expression of Olig2,Tuj1,GFAP,and NeuN at the protein and mRNA levels and to identify cell differentiation.RESULTS AND CONCLUSION:After 72 hours of culture,E14 d embryonic mouse spinal cord tissue cells could form suspended neurospheres,which could be passaged after 5-7 days.Compared with trypsin and papain,TrypLETM Express enzyme combined with blow beating method was used for passage.The cell dispersion rate was high,the activity was good,and more NeuN-and Tuj1-positive neurons differentiated.This study optimized the culture and passaging process of neural stem cells,laying a foundation for further research on stem cell transplantation therapy for spinal cord diseases.