Abstract: The present invention discloses methods for producing and/or propagating virus particles, such as influenza virus particles, that are present in a virus isolate obtained from an infected subject by contacting a host cell with a virus particle and culturing the cell under conditions conducive to propagation of the virus particle. The invention also provides a method for selective propagation of a set of virus particles, such as influenza virus particles present in an influenza isolate, which have an affinity for receptors comprising a specific glycosylation residue.

Abstract: The invention provides compositions comprising one or more isoforms of an erythropoietin (EPO) comprising glycans linked thereto, characterized in that said glycans comprise LewisX structures and on average at least 6 sialic acid moieties per EPO molecule.

Abstract: Methods for producing and/or propagating virus particles that are present in a virus isolate obtained from an infected subject by contacting a host cell with a virus particle and culturing the cell under conditions conducive to propagation of the virus particle are disclosed. A method for selective propagation of a set of virus particles which have an affinity for receptors comprising a specific glycosylation residue are further disclosed. Immortalized human embryonic retina cells comprising a nucleic acid sequence encoding an adenoviral E1A protein integrated into the genome of the cells and a nucleic acid sequence encoding an enzyme involved in post-translational modification of proteins, wherein said nucleic acid sequence encoding the enzyme involved in post-translational modification of proteins is under control of a heterologous promoter are further disclosed.

Abstract: Described are methods for identifying, selecting, and obtaining mammalian cells capable of producing proteinaceous molecules having predetermined post-translational modifications, wherein the post-translational modifications are brought about by the mammalian cell in which the proteinaceous molecule is expressed. Preferably, the predetermined post-translational modifications include glycosylation. Also described are methods for obtaining and producing proteinaceous molecules, using mammalian cells obtainable by a method of the present invention. Preferably, the proteinaceous molecules include erythropoietin (EPO), since EPO's effect depends heavily on its glycosylation pattern. Mammalian cells that have been obtained on the basis of their ability to produce proteins and/or post-translational modifications that are indicative for a predetermined post-translational modification that is desired are also provided.

Abstract: The invention discloses a process for recombinant production of blood coagulation Factor VIII in an immortalized human embryonic retina cell, said cell expressing at least an adenoviral E1A protein and comprising a nucleic acid sequence encoding said Factor VIII, said nucleic acid sequence being under control of a heterologous promoter, said process comprising culturing said cell and expressing the Factor VIII in said cell, and harvesting the expressed Factor VIII. Cells that can be used in the process of the invention are also provided.

Abstract: The invention provides a method for producing at least one polypeptide of interest in a eukaryotic cell, the method comprising: providing a eukaryotic cell comprising nucleic acid encoding the polypeptide of interest; culturing the cell in a suitable medium; and harvesting the at least one polypeptide of interest from the eukaryotic cell, from the suitable medium, or from both the eukaryotic cell and the suitable medium, wherein the eukaryotic cell is a permanent amniocytic cell comprising a nucleic acid sequence encoding adenoviral E1A and E1B proteins. The invention also provides a eukaryotic cell comprising nucleic acid encoding a polypeptide of interest under control of a heterologous promoter, the eukaryotic cell not comprising a structural adenoviral protein, wherein the eukaryotic cell is a permanent amniotic cell comprising a nucleic acid sequence encoding adenoviral E1A and E1B proteins.

Abstract: Described are methods for identifying, selecting, and obtaining mammalian cells capable of producing proteinaceous molecules having predetermined post-translational modifications, wherein the post-translational modifications are brought about by the mammalian cell in which the proteinaceous molecule is expressed. Preferably, the predetermined post-translational modifications include glycosylation. Also described are methods for obtaining and producing proteinaceous molecules, using mammalian cells obtainable by a method of the present invention. Preferably, the proteinaceous molecules includes erythropoietin (EPO), since EPO's effect depends heavily on its glycosylation pattern. Mammalian cells that have been obtained on the basis of their ability to produce proteins and/or post-translational modifications that are indicative for a predetermined post-translational modification that is desired are also provided.

Abstract: Methods for producing and/or propagating virus particles that are present in a virus isolate obtained from an infected subject by contacting a host cell with a virus particle and culturing the cell under conditions conducive to propagation of the virus particle are disclosed. A method for selective propagation of a set of virus particles which have an affinity for receptors comprising a specific glycosylation residue are further disclosed. Immortalized human embryonic retina cells comprising a nucleic acid sequence encoding an adenoviral E1A protein integrated into the genome of the cells and a nucleic acid sequence encoding an enzyme involved in post-translational modification of proteins, wherein said nucleic acid sequence encoding the enzyme involved in post-translational modification of proteins is under control of a heterologous promoter are further disclosed.

Abstract: The present invention discloses methods for producing and/or propagating virus particles, such as influenza virus particles, that are present in a virus isolate obtained from an infected subject by contacting a host cell with a virus particle and culturing the cell under conditions conducive to propagation of the virus particle. The invention also provides a method for selective propagation of a set of virus particles, such as influenza virus particles present in an influenza isolate, which have an affinity for receptors comprising a specific glycosylation residue.