Choi Shin Sik, Rhee Won Jong, Park Tai Hyun
School of Chemical and Biological Engineering, Seoul National University, Gwanak-Gu Shilim-Dong San 56-1, Seoul 151-744, Korea.
Biotechnol Bioeng. 2005 Sep 30;91(7):793-800. doi: 10.1002/bit.20550.
To produce erythropoietin (EPO), Chinese hamster ovary (CHO) cells were first cultured in a medium containing FBS (growth medium) and then in a serum-free medium containing sodium butyrate (production medium). Sodium butyrate increases recombinant protein production, but also induces apoptosis, which reduces cell viability and productivity. In a previous study, we found that silkworm hemolymph (SH), an insect serum, inhibits the apoptosis of insect and mammalian cells. To overcome sodium butyrate-induced apoptosis, we added SH to growth medium. This pretreatment with SH inhibited the sodium butyrate-induced apoptosis of CHO cells and consequently increased their longevity and their ability to produce EPO. As a result, the volumetric productivity of EPO was increased five-fold. SH was found to inhibit cytochrome c release from mitochondria into the cytosol, and prevented the activation of caspase-3 and other subsequent caspase reactions.
为了生产促红细胞生成素（EPO），首先将中国仓鼠卵巢（CHO）细胞在含有胎牛血清的培养基（生长培养基）中培养，然后在含有丁酸钠的无血清培养基（生产培养基）中培养。丁酸钠可增加重组蛋白的产量，但也会诱导细胞凋亡，从而降低细胞活力和生产力。在先前的一项研究中，我们发现昆虫血清家蚕血淋巴（SH）可抑制昆虫和哺乳动物细胞的凋亡。为了克服丁酸钠诱导的细胞凋亡，我们在生长培养基中添加了SH。这种用SH进行的预处理抑制了丁酸钠诱导的CHO细胞凋亡，从而延长了它们的寿命并提高了它们产生EPO的能力。结果，EPO的体积生产力提高了五倍。研究发现，SH可抑制细胞色素c从线粒体释放到细胞质中，并阻止caspase-3的激活以及随后的其他caspase反应。
