Application Of Disposable Flexible Bioreactor In Animal Cell Culture

Bioreactor is an essential instrument for clinical cell therapy and bio pharmaceutical.The incidences of Parkinson’s disease, Alzheimer’s disease and multiple systematrophy and other neurodegenerative disease increased year by year, but there is alack of effective treatment. Cell repair therapy and gene therapy for the treatment ofthese diseases of the nervous system to provide new hope and new methods. Torealize the cell therapy and gene therapy for neurological diseases need plenty ofneural stem cells and virus vectors, in order to solve the bottleneck at present whichcan not scale expansion, we need to explore one optimal bioreactor to meet theamplification of neural stem cell and viral vectors.The traditional bioreactors such as spinner flask, hollow fiber membrane bioreactor,stirred tank bioreactor are hard material,no deformation,non-disposable, high risk ofcross contamination and high cost. To overcome these shortcomings, we havereported a disposable flexible triangular bioreactor, which achieved efficient oxygenin the process of Escherichia coli cultivation, and may provide a good oxygen inculturing animal cells, and promote the virus amplification. Jurkat cells are suspendedcells, like neural stem cells, can obtain a faster proliferation efficiency in highconcentration oxygen conditions. Due to the high cost of neural stem cell culture,hard to achieve, we used Jurkat cells for cultivation, to compare the cell growth andvirus multiplication. The result showed that the flexible bioreactor achieved nearly four-fold higher KLa than spinner and maximum viable cell density and virus titerwas similar between flexible bioreactor and spinner flask at matched KLa of3hr-1.The flexible bioreactor acquired three-fold higher maximal cell density than spinner,when the spinner flask working at maximum speed at75rpm and flexible bioreactor15rpm. In Conclusion: the disposable triangular pyramid bioreactor is an importantinstrument for neural stem cell suspension culture and adenovirus amplification, andprovides an important culture device for cell restrorative therapy and gene therapy ofneurolocigical disease.Objectives1. To make a study of the mechanism of the disposable flexible triangular pyramidbioreactor in suspension culture by comparing KLa, flow pattern, cell growth andvirus titer.2. To explore the optimal culture condition in this suspension bioreactor, we firstlyculture Jurkat in this disposable triangular pyramid bioreactor, to provide areliable cell model for neurosphere suspension culture.3. In order to obtain sufficient quantities of Adenovirus vectors for gene therapy ofneurological diseases，we use the disposable triangular pyramid bioreactor for293A suspension culture on microcarriers.Methods1. To investigate the differences of dissolved oxygen in the disposable flexibletriangular pyramid bioreactor, we make a comparison study of the bioreactorplaced in different heights and different sites in the CO2incubator2. To compare the oxygen transfer pattern, we observe the flow pattern of thedisposable flexible triangular bioreactor and spinner flask.3. To make a comparative study of the volumetric oxygen transfer coefficicent of thedisposable flexible triangular pyramid bioreactor and the spinner flask at the sametemperature, humidity conditions and CO2concentration.4. To evaluate the cell growth of suspension cell and293A suspension culture onmicrocarrier, and the virus titer in the disposable flexible triangular pyramidbioreactor and spinner flask at the same volumetric oxygen transfer coefficient. 5. To make a comparison study of cell growth in the disposable flexible triangularpyramid bioreactor at15rpm and spinner flask75rpm at maximum speed.Results1. There was no significant difference of dissolved oxygen in the disposable flexibletriangular pyramid bioreactor by placing at different heights and different sites inthe CO2incubator;2. Wave mediated oxygen transfer mechanism in the disposable flexible triangularbioreactor was higher efficient than convection and diffusion from air to themedium through increased and renewed gas-liquid surface by turbulent flow inthe spinner flask.3. The disposable flexible triangular pyramid bioreactor achieved nearly five-foldhigher volumetric oxygen transfer coefficient than spinner flask at the sametemperature, humidity conditions and CO2concentration;4. Under the same volumetric oxygen transfer coefficient of3hr-1, maximum viablecell density and virus titer was achieved;5. The flexible bioreactor achieveded three-fold higher maximal cell density thanspinner, when the spinner flask working at maximum speed at75rpm and flexiblebioreactor15rpm.ConclusionThe disposable flexible triangular pyramid achieved higher oxygen transfer, andhigher dissolved oxygen concentration and low fluid shear stress by wave motion.The disposable flexible bioreactor can be more efficient amplification of adenovirusvector. For the need of high oxygen concentration and suspension characteristics ofneural stem cell, the culture conditions in the triangular pyramid may be conducive toit. Therefore the disposable flexible triangular pyramid may provide one essentialcultivation device for cell restorative therapy and gene therapy of neurological disease.