Animal tissue with carbohydrate antigens compatible for human transplantation

• US 7,126,039 B2
• Filed: 03/21/2002
• Issued: 10/24/2006
• Est. Priority Date: 03/21/2001
• Status: Active Grant

• Current Assignee: Geron Corporation
• Original Assignee: Geron Corporation
• Inventors: Clark, A. John, Denning, Chris, Schiff, J. Michael
• Primary Examiner(s): Crouch, Deborah
• Application Number:
  US10/105,963
• Publication Number:
  US 20030068818A1
• Time in Patent Office: 1,678 Days
• Field of Search: 800/24, 800/25, 800 14- 18, 435/1.1, 435/325, 435/354, 435/352
• US Class Current: 800/17
• CPC Class Codes: A01K 2217/075 inducing loss of function, i.e. knock out
• CPC Class Codes: A01K 2227/105 Murine
• CPC Class Codes: A01K 2267/02 Animal zootechnically ameliorated
• CPC Class Codes: A01K 2267/025 Animal producing cells or organs for transplantation
• CPC Class Codes: A01K 67/0271 Chimeric vertebrates, e.g. comprising exogenous cells
• CPC Class Codes: A01K 67/0276 Knock-out vertebrates
• CPC Class Codes: A61K 2035/122 for inducing tolerance or supression of immune responses
• CPC Class Codes: C12N 15/8509 for producing genetically modified animals, e.g. transgenic
• CPC Class Codes: C12N 15/873 Techniques for producing new embryos, e.g. nuclear transfer, manipulation of totipotent cells or production of chimeric embryos
• CPC Class Codes: C12N 2517/02 Cells from transgenic animals
• CPC Class Codes: C12N 2517/04 Cells produced using nuclear transfer
• CPC Class Codes: C12N 2517/10 Conditioning of cells for in vitro fecondation or nuclear transfer
• CPC Class Codes: C12N 2800/108 episomal vectors
• CPC Class Codes: C12N 2800/30 Vector systems comprising sequences for excision in presence of a recombinase, e.g. loxP or FRT
• CPC Class Codes: C12N 9/1051 Hexosyltransferases (2.4.1)
• CPC Class Codes: C12N 9/1276 RNA-directed DNA polymerase (2.7.7.49), i.e. reverse transcriptase or telomerase

Abstract

This disclosure provides a system for generating animal tissue with carbohydrate antigens that are compatible for transplantation into human patients. The tissue is inactivated homozygously for expression of α(1,3)galactosyltransferase, and comprises a transgene for α(1,2)fucosyltransferase. As a result, cell-surface N-acetyl lactosamine is not converted to the Galα(1,3)Gal xenoantigen. Instead, it is converted to Fucα(1,2)Gal, which is H substance, a self-antigen in humans. The tissue may also contain A or B-transferase, which will cause H substance to be converted into other ABO blood group antigens for compatibility with patients of the same blood type. This invention improves transplant compatibility of the xenograft tissue by lessening the risk of reactions resulting from xenoantigen and unconverted N-acetyl lactosamine acceptor determinants.

Claims

1. A transgenic pig whose genome comprises a homozygous inactivation of the α

1,3GT gene, and wherein said genome further comprises a DNA sequence encoding α

1,2FT, operably linked to a promoter and expressed wherein cells, tissue, or organs of said pig exhibit reduced hyperacute rejection.

2. The pig of claim 1, wherein at least part of the DNA sequence of the α

1,3GT gene are replaced with the DNA sequence encoding α

1,2FT.

3. The pig of claim 1, wherein the DNA sequence encoding α

1,2FT is placed under the control of an endogenous α

1,3GT gene promoter.

4. The pig of claim 1, wherein the genome further comprises a DNA sequence encoding a blood group A- or B-transferase.

5. An isolated porcine cell whose genome comprises a homozygous inactivation of the α

1,3GT gene, and wherein said genome further comprises a DNA sequence encoding α

1,2FT, operably linked to a promoter and expressed wherein said cell exhibits reduced hyperacute rejection.

6. The cell of claim 5, wherein at least part of the DNA sequence of the α

1,3GT gene is replaced with the DNA sequence encoding α

1,2FT.

7. The cell of claim 6, wherein the DNA sequence encoding α

1,2FT is placed under the control of an endogenous α

1,3GT gene promoter.

8. The cell of claim 6, wherein the genome further comprises a DNA sequence encoding a blood group A- or B-transferase.

9. Isolated porcine tissue comprising a porcine cell whose genome comprises a homozygous inactivation of the α

1,3GT gene, and wherein said genome further comprises a DNA sequence encoding α

1,2FT, operably linked to a promoter and expressed wherein said tissue exhibits reduced hyperacute rejection.

10. The tissue of claim 9, wherein at least part of the DNA sequence of the α

1,3GT gene is replaced with the DNA sequence encoding α

1,2FT.

11. The tissue of claim 9, wherein the DNA sequence encoding α

1,2FT is placed under the control of an endogenous α

1,3GT gene promoter.

12. The tissue of claim 9, wherein the genome further comprises a DNA sequence encoding a blood group A- or B-transferase.

13. The tissue of claim 9, wherein the tissue is lung tissue, kidney tissue, liver tissue, cardiac tissue, pancreatic tissue, or ocular tissue.

14. A method for making the tissue of claim 9 comprising:

a) obtaining a porcine fibroblast cell whose genome comprises a homozygous inactivation of the α

1,3GT gene, and wherein said genome further comprises a DNA sequence encoding α

1,2FT operably linked to a promoter;

b) transferring the nucleus of the cell to an enucleated porcine oocyte to produce an embryo;

c) engrafting the embryo into the uterus of a host pig;

d) obtaining a cloned pig from the engrafted embryo; and

e) harvesting the tissue from the cloned pig or its progeny.

15. A method for making the tissue of claim 9 comprising:

a) obtaining a telomerized porcine cell whose genome comprises a homozygous inactivation of the α

1,3GT gene, and wherein said genome further comprises a DNA sequence encoding α

1,2FT operably linked to a promoter;

b) transferring the nucleus of the cell to an enucleated porcine oocyte to produce an embryo;

c) engrafting the embryo into the uterus of a host pig;

d) obtaining a cloned pig from the engrafted embryo; and

e) harvesting the tissue from the cloned pig or its progeny.