title: Relationship between sugar chain structure and biological activity of recombinant human erythropoietin produced in Chinese hamster ovary cells.
abstract: Two forms of erythropoietin, EPO-bi and EPO-tetra, with different biological activities were isolated from the culture medium of a recombinant Chinese hamster ovary cell line, B8-300, into which the human erythropoietin gene had been introduced. EPO-bi, an unusual form, showed only one-seventh the in vivo activity and 3 times higher in vitro activity of the previously described recombinant human EPO (standard EPO). In contrast, EPO-tetra showed both in vivo and in vitro activities comparable to those of the standard EPO. EPO-bi, EPO-tetra, and the standard EPO had the same amino acid composition and immunoreactivity. However, structural analyses of their N-linked sugar chains revealed that EPO-bi contains the biantennary complex type as the major sugar chain, while EPO-tetra and the standard EPO contain the tetraantennary complex type as the major sugar chain. From examination of various preparations of recombinant human EPO, we found a positive correlation between the in vivo activity of EPO and the ratio of tetraantennary to biantennary oligosaccharides. These results suggest that higher branching of the N-linked sugar chains is essential for effective expression of in vivo biological activity of EPO.
authors: Pharmaceutical Laboratory, Kirin Brewery, Gunma, Japan.
authors: M
authors: M
authors: Takeuchi
authors: N
authors: N
authors: Inoue
authors: T W
authors: TW
authors: Strickland
authors: M
authors: M
authors: Kubota
authors: M
authors: M
authors: Wada
authors: R
authors: R
authors: Shimizu
authors: S
authors: S
authors: Hoshi
authors: H
authors: H
authors: Kozutsumi
authors: S
authors: S
authors: Takasaki
authors: A
authors: A
authors: Kobata
mesh_terms: D000818:Animals; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D004921:Erythropoietin / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology*; D005260:Female; D005796:Genes; D006801:Humans; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000302:isolation & purification*; D010053:Ovary; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000494:pharmacology; D014162:Transfection
chemical_list: D009844:Oligosaccharides; D011994:Recombinant Proteins; D004921:Erythropoietin