Microfluidic chip-based single-cell cloning to accelerate biologic production timelines

Cell line development (CLD) represents a critical, yet time-consuming, step in the biomanufacturing process as significant resources are devoted to the scale-up and screening of several hundreds to thousands of single-cell clones. Typically, transfected pools are fully recovered from selection and characterized for growth, productivity, and product quality to identify the best pools suitable for single-cell cloning (SCC) using limiting dilution or fluorescence-activated cell sorting (FACS). Here we report the application of the Berkeley Lights Beacon Instrument (BLI) in an early SCC process to accelerate the CLD timeline. Transfected pools were single-cell cloned when viabilities reached greater than 85% or during selection when viabilities were less than 30%. Clones isolated from these accelerated processes exhibited comparable growth, productivity, and product quality to those derived from a standard CLD process and fit into an existing manufacturing platform. With these approaches, up to a 30% reduction in the overall CLD timeline was achieved. Furthermore, early process-derived clones demonstrated equivalent long-term stability compared with standard process-derived clones over 50 population doubling levels (PDLs). Taken together, the data supported early SCC on the BLI as an attractive approach to reducing the standard CLD timeline while still identifying clones with acceptable manufacturability.