Step-up/step-down perfusion approach for increased mAb 520C9 production by a hybridoma cell line

Abstract

The hybridoma cell line, HB-8696, produces a monoclonal antibody, 520C9 (mouse IgG(1)) that recognizes the breast cancer oncoprotein, c-erbB2. The effect of perfusion rate (volume of fresh feed/working volume of reactor/day) on cell growth and mAb production was investigated but perfusion at a constant rate and at an arbitrarily increased rate could not maintain exponential cell growth or a higher specific mAb production rate. An optimum step-up/step-down perfusion strategy is therefore proposed for maintaining a steady state production phase at high cell density for ten days. The optimum step-up perfusion could achieve fast cell growth by avoiding any nutrient limited condition and the following optimum step-down perfusion could potentially maintain high live cell density and reduced product dilution as well. The maximum viable cell achieved under optimum perfusion strategy was 2.3 × 10(7) cells/ml which was 19-fold higher than in optimum batch culture. The mAb yield and volumetric productivity were significantly improved to 52 and 50 mg/l day compared to 25 and 3.8 mg/l day in optimum batch, respectively, and could be maintained for up to ten days.

Simulating gas-liquid mass transfer in a spin filter bioreactor

“…This problem is increased in high cell density bioreactors due to oxygen transfer rate limitations affecting cell growth and productivity. Such limitations are common in perfusion cell cultures leading to anoxic process, cellular damage and therefore loss of cell viability [1].…”

“…The spin-filter device minimizes the loss of cells through the bioreactor harvest. Consequently biomass productivity is increased substantially compared to batch or fed batch mode [1]. However oxygen requirements are proportional to cell density causing mass transfer limitations.…”