Patents by Inventor Dirk J. E. Opstelten

Dirk J. E. Opstelten has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Methods to obtain recombinant proteins with increased sialylation from cells that express adenovirus E1A protein, and proteins obtained thereby
    Patent number: 8524477
    Abstract: Provided are compositions comprising one or more isoforms of an erythropoietin (“EPO”) comprising glycans linked thereto, wherein the glycans have Lewis x structures and on average at least six sialic acid moieties per EPO molecule. Further provided are methods for obtaining a composition comprising one or more isoforms of EPO comprising glycans linked thereto, wherein the glycans comprise on average at least six sialic acids per EPO molecule and from zero to two Lewis x structures, the method comprising: a) providing a eukaryotic cell containing a nucleic acid sequence encoding an adenoviral E1A protein in expressible format and a nucleic acid encoding EPO in expressible format, wherein the cell further contains a nucleic acid sequence encoding a sialyltransferase, e.g.
    Type: Grant
    Filed: November 23, 2009
    Date of Patent: September 3, 2013
    Assignee: Crucell Holland B.V.
    Inventor: Dirk J. E. Opstelten
  • Methods of producing erythropoietin isoforms comprising Lewis-X structures and high sialic acid content and compositions of the same
    Patent number: 7833753
    Abstract: Disclosed are immortalized human embryonic retina cells, having a nucleic acid sequence encoding an adenoviral E1A protein integrated into the genome of the cells, and further comprising a nucleic acid sequence encoding an enzyme involved in post-translational modification of proteins, such as a sialyltransferase, wherein the nucleic acid sequence encoding the enzyme involved in post-translational modification of proteins is under control of a heterologous promoter. Methods for producing recombinant proteins from such cells and obtaining such recombinant proteins having increased sialylation are provided as are novel compositions of isoforms of erythropoietin.
    Type: Grant
    Filed: June 20, 2007
    Date of Patent: November 16, 2010
    Assignee: Crucell Holland B.V.
    Inventors: Dirk J. E. Opstelten, Alphonsus G. C. M. UytdeHaag
  • Methods to obtain recombinant proteins with increased sialylation from cells that express adenovirus E1A protein, and proteins obtained thereby
    Patent number: 7642078
    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.
    Type: Grant
    Filed: December 28, 2005
    Date of Patent: January 5, 2010
    Assignee: Crucell Holland B.V.
    Inventor: Dirk J. E. Opstelten
  • Compositions of erythropoietin isoforms comprising Lewis-X structures and high sialic acid content
    Patent number: 7297680
    Abstract: Disclosed are immortalized human embryonic retina cells, having a nucleic acid sequence encoding an adenoviral E1A protein integrated into the genome of the cells, and further comprising a nucleic acid sequence encoding an enzyme involved in post-translational modification of proteins, such as a sialyltransferase, wherein said nucleic acid sequence encoding the enzyme involved in post-translational modification of proteins is under control of a heterologous promoter. Methods for producing recombinant proteins from such cells and obtaining such recombinant proteins having increased sialylation are provided as are novel compositions of isoforms of erythropoietin.
    Type: Grant
    Filed: April 8, 2005
    Date of Patent: November 20, 2007
    Assignee: Crucell Holland B.V.
    Inventors: Dirk J. E. Opstelten, Alphonsus G. C. M. UytdeHaag