Supplementation of Concentrated Amino Acids for the Enhanced roduction of hCTLA4Ig in Transgenic Rice Cell Cultures

초록

Human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig) was produced and secreted when sugar was depleted in transgenic plant cell cultures (Oryza sativa L.) using RAmy3D promoter. Due to the inducing property of the promoter, it was necessary to change the growth medium into sugar-free medium to produce hCTLA4Ig [1]. Since the two-stage culture is a complex process in large-scale, a fed-batch method was designed with the addition of concentrated amino acids without changing medium to induce hCTLA4Ig production in a 15-L stirred-tank bioreactor [2]. In this study, concentrated amino acid mixtures were added to induce the target protein at day 10. However, addition of concentrated amino acid did not show the same level of hCTLA4Ig as that in flask culture. Separate optimization of media for the cultures in bioreactor might be needed. Two-stage culture and fed-batch culture with concentrated amino acids showed similar results in terms of maximum cell density (41.6, 38.2 gDCW/L) and maximum hCTLA4Ig concentration (11.1, 12.4 mg/L), respectively. These results might be useful for the enhanced production of hCTLA4Ig in transgenic rice culture.