Establishment of a semi-continuous scale-down clone screening model for intensified perfusion culture.

Purpose: Perfusion cultures have been extensively used in the biotechnology industry to achieve high yields of recombinant products, especially those with stability issue. The WuXiUP™ platform represents a novel intensified perfusion that can achieve ultra-high productivity. This study describes a representative scale-down 24-deep well plate (24-DWP) cell culture model for intensified perfusion clone screening.

Methods: Clonal cell lines were expanded and evaluated in 24-DWP semi-continuous culture. Cell were sampled and counted daily with the aid of an automated liquid handler and high-throughput cell counter. To mimic perfusion culture, 24-DWP plates were spun down and resuspended with fresh medium daily. Top clones were ranked based on growth profiles and productivities. The best performing clones were evaluated on bioreactors.

Results: The selected clones achieved volumetric productivity (Pv) up to 5 g/L/day when expressing a monoclonal antibody, with the accumulative harvest Pv exceeding 60 g/L in a 21-day cell culture. Product quality attributes of clones cultured in 24-DWP were comparable with those from bioreactors. A high seeding strategy further shortened the clone screening timeline.

Conclusion: In this study, a 24-DWP semi-continuous scale-down model was successfully developed to screen for cell lines suitable for intensified perfusion culture.