Sequential adaptation to serum-free medium for Vero cells cultivation on ultraviolet/ozone (UVO) treated microcarrier

Abstract

The adoption of serum-free media (SFM) in cell culture has gained prominence as an alternative to serum-supplemented media (SSM) owing to concerns regarding serum variability and quality assurance. Vero cells, widely utilized in viral vaccine production for their susceptibility to various viruses, were the focus of this study. Our primary objective was to adapt Vero cells from SSM to SFM and subsequently upscale the culture from T-flasks to spinner vessels using ultraviolet/ozone (UVO) treated polystyrene (PS) and polycaprolactone (PCL) microcarriers. Cell counting was conducted via haemocytometer and inverted phase microscopy. The results indicated that SFM-adapted Vero cells achieved higher maximum cell concentrations compared to those cultured in SSM, along with a shorter doubling time. However, during cultivation in spinner vessels, Vero cells exhibited lower maximum cell concentrations compared to T-flask cultures, attributed to factors such as cell inoculum size and microcarrier hydrophilicity. This study highlights the successful adaptation of Vero cells to SFM and the potential benefits in terms of cell density and growth kinetics. Furthermore, it sheds light on the challenges encountered during culture upscale, offering valuable insights for optimizing future large-scale production processes. The findings contribute to the advancement of serum-free cell culture systems and their applicability in the production of viral vaccines.