Effect of Inoculum Size and Age on hCTLA4Ig Production in Tansgenic Rice Cell Cultures

초록

Recombinant human cytotoxic T-lymphocyte antigen 4-immunoglobulin (hCTLA4Ig) was produced by sugar starvation using RAmy3D promoter in transgenic rice cell suspension cultures. Generally, the initial inoculum density affects cell growth in plant cell suspension cultures. Under minimum inoculum density, cell growth dose not proceed. The inoculum age is one of the most critical factors for enhanced production of protein since it influences the specific productivity of cells. Production of hCTLA4Ig was started by changing the growth medium into sugar-depleting medium. In this study, it was confirmed that the state of cells, inoculum size and age influenced protein production. In order to evaluate the effects on cell viability and productivity during production stage, the inoculum ages were set at day 2, 4, 6 and 8, and the inoculum size at 1, 2, 3, 4 and 5 gFCW, respectively. As a result, the highest cell viability and protein production were achieved at day 4 in early exponential phase. In conclusion, the productivity of hCTLA4Ig could be enhanced by the optimization of the inoculum size and age of plant cell suspension cultures.