title: [Extracellular sialidase degrades sialic acid in recombinant human erythropoietin produced by an industrial Chinese hamster ovary cell strain].
abstract: To investigate the N-glycosylation characteristics of recombinant human erythropoietin (rhEPO) produced by an industrial Chinese hamster ovary (CHO) cell line that is currently used in a large scale manufacturing process, we cultured this cell strain in static mode. The produced rhEPO in the culture supernatant was analyzed using isoelectric focusing (IEF) and Ricinus communis agglutinin-I (RCA-I) lectin precipitation. The lactate dehydrogenase (LDH) and sialidase activity in the serum-free supernatant were assayed as well. The analyses revealed that this cell strain could produce rhEPO with high sialic acid content, but during prolonged culture, cell viability decreased with time whilst the activity of sialidase present in the supernatant increased. The loss in rhEPO quality was due to a decrease in terminal sialic acid on the N-glycans, caused by sialidase degradation. The methods and findings in this paper serve as basis for further investigation of industrial production process.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
authors.forename: Yingwei
authors.initials: Y
authors.lastname: Liu
authors.forename: Xiangshan
authors.initials: X
authors.lastname: Zhou
authors.forename: Haifeng
authors.initials: H
authors.lastname: Liu
authors.forename: Zhiwei
authors.initials: Z
authors.lastname: Song
authors.forename: Yuanxing
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000818:Animals; D016466:CHO Cells / Q000378:metabolism*; D018929:Cell Culture Techniques / Q000379:methods; D006224:Cricetinae; D003412:Cricetulus; D004921:Erythropoietin / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D005818:Genetic Engineering; D006801:Humans; D019158:N-Acetylneuraminic Acid / Q000378:metabolism*; D009439:Neuraminidase / Q000378:metabolism*; D059748:Proteolysis; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism
chemical_list: D011994:Recombinant Proteins; D004921:Erythropoietin; D009439:Neuraminidase; D019158:N-Acetylneuraminic Acid