title: Analysis of the N-glycans of recombinant human Factor IX purified from transgenic pig milk.
abstract: Glycosylation of recombinant proteins is of particular importance because it can play significant roles in the clinical properties of the glycoprotein. In this work, the N-glycan structures of recombinant human Factor IX (tg-FIX) produced in the transgenic pig mammary gland were determined. The majority of the N-glycans of transgenic pig-derived Factor IX (tg-FIX) are complex, bi-antennary with one or two terminal N-acetylneuraminic acid (Neu5Ac) moieties. We also found that the N-glycan structures of tg-FIX produced in the porcine mammary epithelial cells differed with respect to N-glycans from glycoproteins produced in other porcine tissues. tg-FIX contains no detectable Neu5Gc, the sialic acid commonly found in porcine glycoproteins produced in other tissues. Additionally, we were unable to detect glycans in tg-FIX that have a terminal Galalpha(1,3)Gal disaccharide sequence, which is strongly antigenic in humans. The N-glycan structures of tg-FIX are also compared to the published N-glycan structures of recombinant human glycoproteins produced in other transgenic animal species. While tg-FIX contains only complex structures, antithrombin III (goat), C1 inhibitor (rabbit), and lactoferrin (cow) have both high mannose and complex structures. Collectively, these data represent a beginning point for the future investigation of species-specific and tissue/cell-specific differences in N-glycan structures among animals used for transgenic animal bioreactors.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, USA.
authors.forename: Geun-Cheol
authors.initials: GC
authors.lastname: Gil
authors.forename: William H
authors.initials: WH
authors.lastname: Velander
authors.forename: Kevin E
authors.initials: KE
authors.lastname: Van Cott
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D000990:Antithrombin III / Q000737:chemistry; D002417:Cattle; D050718:Complement C1 Inhibitor Protein / Q000737:chemistry; D005164:Factor IX / Q000096:biosynthesis / Q000737:chemistry*; D005260:Female; D006031:Glycosylation; D006041:Goats; D006801:Humans; D007781:Lactoferrin / Q000737:chemistry; D008321:Mammary Glands, Animal / Q000378:metabolism; D008892:Milk / Q000737:chemistry*; D019158:N-Acetylneuraminic Acid / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry*; D011247:Pregnancy; D011817:Rabbits; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D013045:Species Specificity; D034421:Sus scrofa
chemical_list: D050718:Complement C1 Inhibitor Protein; D011134:Polysaccharides; D011994:Recombinant Proteins; D000990:Antithrombin III; D005164:Factor IX; D007781:Lactoferrin; D019158:N-Acetylneuraminic Acid