Characterization and evaluation of a novel polylactic acid-made bioreactor for large-scale adherent cell expansion

Abstract Efficient large-scale expansion of adherent mammalian cells is essential for the production of recombinant proteins, viral vectors, and vaccines. Conventional multilayer flasks rely on scale-out approaches, require extensive manual handling, and lack monitoring process control compared to bioreactors. Here, we evaluate the CellScrew®, a dynamic 2D culture system available in three sizes ranging from 851 to 10,197 cm 2 , in which cell culture surfaces are continuously rotated, generating controlled hydrodynamic conditions that enhance mass transfer while reducing material consumption. Hydrodynamic conditions and oxygen transfer were characterized, with k L a values up to 6.69 ± 0.10 h −1 . In this context, we assessed cell attachment, proliferation, metabolism, and harvest performance using human embryonic kidney 293 (HEK-293), murine melanoma (B16-F10), and murine colon carcinoma (CT-26 WT) cells, which serve as established model systems for biotherapeutic manufacturing applications such as viral vectors and vaccine production. The system supported cell densities up to 7.7 × 10E5 cells per cm 2 (HEK-293), 8.7 × 10E4 cells per cm 2 (B16-F10), and 1.1 × 10E5 cells per cm 2 (CT-26 WT) with viabilities above 92%, comparable to multilayer flasks. Glucose consumption and lactate accumulation indicated stable metabolic activity. Mechanical harvesting enabled recovery efficiencies exceeding 89% while reducing detachment reagent usage by 67%. Overall, these results suggest that the CellScrew® can support robust adherent cell expansion with potential improvements in process efficiency and reduced resource consumption, indicating that it may represent a scalable and potentially more sustainable alternative to traditional multilayer platforms. Key points • CellScrew® reaches up to 0.77 ± 0.14 × 10E6 cells per cm 2 (cell-line dependent). • Harvest efficiency with 67% less detachment reagent use. • High oxygen transfer (kLa up to 6.69 ± 0.10 h−1) enables efficient culture.