Method for manufacturing glycoproteins having human-type glycosylation

1. A method of manufacturing a glycoprotein having a sugar chain, comprising a step in which a transformed plant cell is produced by introducing to a plant cell a gene encoding a mammalian β 1,4-galactosyltransferase enzyme and a gene of an exogenous glycoprotein, and a step in which the produced transformed plant cell is cultivated.

2. The method according to claim 1 , wherein the β1,4-galactosyltransfease enzyme is an enzyme which transfers a galactose residue to a non-reducing terminal acetylglucosamine residue.

3. The method according to claim 1 , wherein the glycoprotein sugar chain comprises a core sugar chain and an outer sugar chain, wherein the core sugar chain comprises a plurality of mannose and acetylglucosamine residues, and wherein the outer sugar chain contains a terminal sugar portion with a non-reducing terminal galactose.

4. The method according to claim 3 , wherein the outer sugar chain has a straight chain configuration.

5. The method according to claim 3 , wherein the outer sugar chain has a branched configuration.

6. The method according to claim 5 , wherein the branched sugar chain portion has a mono-, bi-, tri, or tetra-configuration.

7. The method according to claim 1 , wherein the mammalian β1,4-galactosyltransferase is a human β1,4-galactosyltransferase.

8. A transformed plant cell having a sugar chain adding mechanism comprising a mammalian β1,4-galactosyltransferase enzyme which transfers a galactose residue to a non-reducing terminal acetylglucosamine residue, wherein the sugar chain adding mechanism adds a sugar chain containing a core sugar chain and an outer sugar chain, wherein the core sugar chain comprise a plurality of mannose and acetylglucosamine residues, and wherein the outer sugar chain contains a terminal sugar chain portion with a non-reducing terminal galactose.

9. The transformed plant cell according to claim 8 , wherein the plant cell is further transformed with a gene of a second enzyme.

10. The transformed plant cell according to claim 9 , wherein the second enzyme is selected from the group consisting of Mannosidase I, Mannosidase II, and N-acetylylycosaminyltransferase I (GlcNAc I).

11. A transformed plant regenerated from the plant cell of claim 8 .

12. A method of manufacturing a glycoprotein, which method includes introducing into a plant cell a gene encoding a β1,4-galactosyltransferase of human origin and further introducing a gene encoding an exogenous glycoprotein selected from the group consisting of enzymes, hormones, cytokines, antibodies, vaccines, receptors and serum proteins, the glycoprotein produced including a core sugar chain including a plurality of mannose and acetylglucosamine residues, and an outer sugar chain containing a terminal sugar chain portion with a non-reducing terminal galactose.

13. The method according to claim 12 , which method further includes introducing a gene encoding a second enzyme.

14. The method according to claim 13 , wherein the second enzyme is selected from the group consisting of Mannosidase I, Mannosidase II, and N-acetylglycosaminyltransferase I (GlcNAc I).

15. The method according to claim 12 , wherein the exogenous glycoprotein encoded by the introduced gene is an enzyme selected from the group consisting of horseradish peroxidase, kinase, glucocerebrosidase, α-galactosidase, tissue-type plasminogen activator (TPA), and 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase.

16. The method according to claim 12 , wherein the exogenous glycoprotein encoded by the introduced gene is a hormone or cytokine selected from the group consisting of enkephalin, interferon-alpha, granulocyte-macrophage colony stimulating factor (GM-CSF), granulocyte colony stimulating factor (G-CSF), chorion stimulating hormone, interleukin-2, interferon-beta, interferon-gamma, erythropoietin, vascular endothelial growth factor, human choriogonadotropin (HCG), leuteinizing hormone (LH), thyroid stimulating hormone (TSH), prolactin, and ovary stimulating hormone.

17. The method according to claim 12 , wherein the exogenous glycoprotein encoded by the introduced gene is an antibody selected from immunoglobulin G (IgG) or single chain variable region antibody fragments (scFV).

18. The method according to claim 12 , wherein the plant cell is from a plant selected from the group consisting of plants in the families of Solanaceae, Poaeae, Brassicaceae, Rosaceae, Leguminosae, Curcurbitaceae, Lamiaceae, Liliaceae, Chenopodiaceae, and Umbelliferae.

19. The method according to claim 18 , wherein the plant cell is from a plant selected from the group consisting of tobacco, tomato, potato, rice, maize, radish, soybean, peas, alfalfa, and spinach.