We are looking into scale up of BHK cell cultures from shake flasks to a Wave and experience sluggish growth of the cells in the bioreactor. Do you have recommendations for optimizing the culture conditions?

Answer

When transferring a clone to a new cultivation system, it is important to make the most out of the characterization data generated in the previous one. E.g. what is the optimum seeding concentration, are the cells very sensitive to the cultivation pH, what is the limiting nutrient in the cultivation medium used, how long can the exponential growth phase be maintained, what is the maximum cell concentration reached etc.
As mentioned in an earlier question, it is beneficial for cell adaptation to any bioreactor to inoculate at relatively high cell concentrations and put special emphasis on equilibrating the bioreactor (T, pH, DO) before cell transfer.
A parallel culture in the previously established cultivation system using the same inoculum and cultivation medium should be run. This will facilitate the decision if lack of cell growth or recombinant protein production is to be attributed to the inoculum quality, the cultivation medium or the bioreactor.