Cells in which activity of the protein involved in transportation of GDP-fucose is reduced or lost
View Patent ↗A cell in which the activity of a protein relating to transport of an intracellular sugar nucleotide, GDP-fucose, to the Golgi body is more decreased or deleted than its parent cell; a process for producing an antibody composition using the cell; a transgenic non-human animal or plant or the progenies thereof, in which genome is modified so as to have a decreased or deleted activity of a protein relating to transport of an intracellular sugar nucleotide, GDP-fucose, to the Golgi body; a process for producing an antibody composition from the animal or plant; and a medicament comprising the antibody composition.
1. A process for producing an antibody composition comprising:
culturing a transformed mammalian cell into which a gene encoding an antibody molecule has been introduced and in which the activity of a GDP-fucose transporter of the transformed cell is deleted by a genomic gene disruption technique which comprises targeting a gene encoding a GDP-fucose transporter, wherein the gene encoding the GDP-fucose transporter is a DNA comprising the nucleotide sequence of SEQ ID NO:1, in a medium to produce the antibody in the culture; and
recovering a composition comprising the antibody from the culture.
2. A process for producing an antibody composition comprising:
culturing an antibody producing mammalian cell in which the activity of a GDP-fucose transporter of the cell is deleted by a genomic gene disruption technique which comprises targeting a gene encoding a GDP-fucose transporter, wherein the gene encoding the GDP-fucose transporter is a DNA comprising the nucleotide sequence of SEQ ID NO:1, in a medium to produce the antibody in the culture; and recovering and purifying a composition comprising the antibody from the culture.
3. The process according to claim 1 or 2 , wherein the antibody composition has a higher antibody-dependent cell-mediated cytotoxic activity than an antibody composition produced by its parent cell.
4. The process according to claim 3 , wherein the antibody composition having a higher antibody-dependent cell-mediated cytotoxic activity has a higher ratio of a sugar chain in which fucose is not bound to N-acetylglucosamine in the reducing end in the sugar chain among total complex N-glycoside-linked sugar chains bound to the Fc region in the antibody composition than an antibody composition produced by the parent cell.
5. The process of claim 4 , wherein the sugar chain in which fucose is not bound is a sugar chain in which 1-position of the fucose is not bound to 6-position of N-acetylglucosamine in the reducing end through α-bond in a complex N-glycoside-linked sugar chain.
6. The process of claim 1 or 2 , wherein the cell is resistant to a lectin which recognizes a sugar chain in which 1-position of fucose is bound to 6-position of N-acetylglucosamine in the reducing end through α-bond in a complex N-glycoside-linked sugar chain.
7. The process of claim 6 , wherein the cell is resistant to at least one lectin selected from the group consisting of the following (a) to (d):
(a) a Lens culinaris lectin
(b) a Pisum sativum lectin
(c) a Vicia faba lectin
(d) a Aleuria aurantia lectin.
8. The process according to claim 1 or 2 , wherein the antibody molecule is selected from the group consisting of the following (a) to (d):
(a) a human antibody;
(b) a humanized antibody;
(c) an antibody fragment comprising the Fc region of (a) or (b);
(d) a fusion protein comprising the Fc region of (a) or (b).
9. The process according to claim 1 or 2 , wherein the antibody molecule belongs to an IgG class.
10. A process for producing an antibody composition comprising culturing a transformed mammalian cell into which a gene encoding an antibody molecule has been introduced and in which the activity of a GDP-fucose transporter of the transformed cell is deleted by a genomic gene disruption technique which comprises targeting a gene encoding a GDP-fucose transporter, wherein the GDP-fucose transporter is a protein comprising the amino acid sequence of SEQ ID NO:2, in a medium to produce the antibody in the culture; and recovering a composition comprising the antibody from the culture.
11. A process for producing an antibody composition comprising:
culturing an antibody producing mammalian cell in which the activity of a GDP-fucose transporter of the cell is deleted by a genomic gene disruption technique which comprises targeting a gene encoding a GDP-fucose transporter, wherein the GDP-fucose transporter is a protein comprising the amino acid sequence of SEQ ID NO:2, in a medium to form and accumulate the antibody in the culture; and
recovering an antibody composition comprising the antibody from the culture.
12. The process according to claim 10 or 11 , wherein the antibody composition has a higher antibody-dependent cell-mediated cytotoxic activity than an antibody composition produced by its parent cell.
13. The process according to claim 12 , wherein the antibody composition having a higher antibody-dependent cell-mediated cytotoxic activity has a higher ratio of a sugar chain in which fucose is not bound to N-acetylglucosamine in the reducing end in the sugar chain among total complex N-glycoside-linked sugar chains bound to the Fc region in the antibody composition than an antibody composition produced by the parent cell.
14. The process of claim 13 , wherein the sugar chain in which fucose is not bound is a sugar chain in which 1-position of the fucose is not bound to 6-position of N-acetylglucosamine in the reducing end through α-bond in a complex N-glycoside-linked sugar chain.
15. The process of claim 12 or 11 , wherein the cell is resistant to a lectin which recognizes a sugar chain in which 1-position of fucose is bound to 6-position of N-acetylglucosamine in the reducing end through α-bond in a complex N-glycoside-linked sugar chain.
16. The process of claim 15 , wherein the cell is resistant to at least one lectin selected from the group consisting of the following (a) to (d):
(a) a Lens culinaris lectin
(b) a Pisum sativum lectin
(c) a Vicia faba lectin
(d) a Aleuria aurantia lectin.
17. The process according to claim 10 or 11 , wherein the antibody molecule is selected from the group consisting of the following (a) to (d):
(a) a human antibody;
(b) a humanized antibody;
(c) an antibody fragment comprising the Fc region of (a) or (b);
(d) a fusion protein comprising the Fc region of (a) or (b).
18. The process according to claim 10 or 11 wherein the antibody molecule belongs to an IgG class.