Bioengineering Protocols for Neural Precursor Cell Expansion

Abstract

Neural precursor cells (NPCs) isolated from different regions of the developing or adult CNS may represent a new source of cells that may have utility in future cell replacement therapies aimed at treating neurodegenerative disorders. Moreover, these cells may have applications in a number of non-clinical areas from basic biological research to gene and drug delivery. However, their sparse concentration within the CNS means that they can only be isolated in small quantities, and thus need to be expanded to numbers that are sufficient for clinical and non-clinical applications. This chapter discusses the cell-handling protocols relevant to the expansion of murine NPCs and human NPCs in both standard tissue culture flasks (as effective means for handling the small quantities of stem cells following isolation from primary tissue) and suspension bioreactors (as highly efficient mode of culture for production of large number of cells in a standardized, controlled manner). Considering that mammalian NPCs can grow under serum-free conditions as neurospheres, or adhere to the culture flask surface, passaging protocols concerning aggregate dissociation techniques, cell sampling and inoculation procedures are described for both floating aggregates of cells and adherent cultures. Special attention is paid to important design considerations (i.e., mass transfer and culture hydrodynamics) as well as process control techniques as crucial parameters to achieve a reproducible and productive cell expansion process in suspension bioreactors.