title: Beneficial effect of silkworm hemolymph on a CHO cell system: Inhibition of apoptosis and increase of EPO production.
abstract: 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.
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University, Gwanak-Gu Shilim-Dong San 56-1, Seoul 151-744, Korea.
authors.forename: Shin Sik
authors.initials: SS
authors.lastname: Choi
authors.forename: Won Jong
authors.initials: WJ
authors.lastname: Rhee
authors.forename: Tai Hyun
authors.initials: TH
authors.lastname: Park
mesh_terms: D000818:Animals; D017209:Apoptosis; D012831:Bombyx; D016466:CHO Cells; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D018929:Cell Culture Techniques; D002470:Cell Survival; D006224:Cricetinae; D003470:Culture Media / Q000737:chemistry*; D016895:Culture Media, Serum-Free; D045304:Cytochromes c / Q000378:metabolism; D003593:Cytoplasm / Q000737:chemistry; D053938:DNA Fragmentation; D004921:Erythropoietin / Q000096:biosynthesis*; D005285:Fermentation; D006458:Hemolymph
chemical_list: D003470:Culture Media; D016895:Culture Media, Serum-Free; D004921:Erythropoietin; D045304:Cytochromes c; D053148:Caspase 3; D020169:Caspases