Design and operation of bioreactor systems for the expansion of pluripotent stem cell-derived neural stem cells

Neurodegenerative disorders, such as Parkinson´s disease, Huntington´s disease, and multiple sclerosis, affect millions of people worldwide, with devastating impact on the patients and families. A reliable method to obtain cells for replacement therapy, using ex-vivo culture techniques, would be of great value for the treatment of these conditions. This project focuses on the development of bioreactor culture systems for the large-scale expansion of neural stem cells, starting with a model line of mouse embryonic stem cell-derived neural stem cells under adherent culture conditions. Adherent conditions are an alternative to conventional culture of NS cells as aggregates and may circumvent problems associated with this system. Small scale stirred bioreactors were successfully used for mNS cell expansion, with microcarriers to support cell adhesion and proliferation, with retention of neural stem/progenitor cell markers. The system was optimized by determining the best values for parameters like stirring speed, microcarrier concentration or feeding regimen. The system here described may open a new door for applications requiring high numbers of mouse neural cells, providing an efficient way for their generation. Furthermore, the know-how obtained with this work may be applied for the development of an equivalent system for human cells, which may find clinical applications.