Expression of xenogenous (human) immunoglobulins in cloned, transgenic ungulates
View Patent ↗The present invention relates to the production of a transgenic bovine which comprises a genetic modification that results in inactivation and loss of expression of its endogenous antibodies, and the expression of xenogenous antibodies, preferably human antibodies. This is effected by inactivation of the IgM heavy chain expression and, optionally, by inactivation of the Ig light chain expression, and by the further introduction of an artificial chromosome which results in the expression of non-bovine antibodies, preferably human antibodies.
1. A transgenic ungulate whose cells comprise one or more artificial chromosomes, each artificial chromosome comprising one or more xenogenous immunoglobulin heavy or light chain loci that undergo rearrangement and are expressed in B cells to produce xenogenous immunoglobulin in response to exposure to one or more antigens.
2. The transgenic ungulate of claim 1 , wherein said xenogenous immunoglobulin is human immunoglobulin.
3. The transgenic ungulate of claim 1 , wherein said immunoglobulin loci comprise both a human immunoglobulin light chain locus and a human immunoglobulin heavy chain locus.
4. The transgenic ungulate of claim 1 , wherein said one or more artificial chromosomes comprise a chromosome fragment.
5. The transgenic ungulate of claim 4 , wherein said artificial chromosome is a YAC or BAC.
6. The transgenic ungulate of claim 1 , wherein said artificial chromosome is a human artificial chromosome.
7. The transgenic ungulate of claim 6 , wherein said human artificial chromosome is a ΔHAC or ΔΔHAC.
8. The transgenic ungulate of claim 6 , wherein said human artificial chromosome is derived from one or more of human chromosome 14, human chromosome 2, and human chromosome 22.
9. The transgenic ungulate of claim 1 , wherein said ungulate is a bovine, ovine, porcine, or caprine.
10. The transgenic ungulate of claim 9 , wherein said ungulate is a porcine.
11. The transgenic ungulate of claim 1 , wherein said artificial chromosome is integrated into an endogenous chromosome of the ungulate.
12. The transgenic ungulate of claim 1 , wherein said artificial chromosome is maintained independently from the endogenous chromosomes of the ungulate.
13. An isolated ungulate somatic cell comprising one or more artificial chromosomes, each artificial chromosome comprising one or more xenogenous immunoglobulin heavy or light chain loci that undergo rearrangement and are expressed in B cells to produce xenogenous immunoglobulin in response to exposure to one or more antigens.
14. The ungulate somatic cell of claim 13 , wherein said xenogenous immunoglobulin is human immunoglobulin.
15. The ungulate somatic cell of claim 14 , wherein said immunoglobulin loci comprise both a human immunoglobulin light chain locus and a human immunoglobulin heavy chain locus.
16. The ungulate somatic cell of claim 13 , wherein said one or more artificial chromosomes comprise a chromosome fragment.
17. The ungulate somatic cell of claim 16 , wherein said artificial chromosome is a YAC or BAC.
18. The ungulate somatic cell of claim 13 , wherein said artificial chromosome is a human artificial chromosome.
19. The ungulate somatic cell of claim 18 , wherein said human artificial chromosome is a ΔHAC or ΔΔHAC.
20. The ungulate somatic cell of claim 18 , wherein said human artificial chromosome is derived from one or more of human chromosome 14, human chromosome 2, and human chromosome 22.
21. The ungulate somatic cell of claim 13 , wherein said cell is a fetal fibroblast or B-cell.
22. The ungulate somatic cell of claim 13 , wherein said ungulate is a bovine, ovine, porcine, or caprine.
23. The ungulate somatic cell of claim 13 , wherein said ungulate is a porcine.
24. The transgenic ungulate cell of claim 13 , wherein said artificial chromosome is integrated into an endogenous chromosome of the cell.
25. The transgenic ungulate cell of claim 13 , wherein said artificial chromosome is maintained independently from the endogenous chromosomes of the cell.
26. A method of producing xenogenous antibodies against one or more antigens, said method comprising the steps of:
(a) administering one or more antigens to a transgenic ungulate whose cells comprise one or more artificial chromosomes, each artificial chromosome comprising one or more xenogenous immunoglobulin heavy or light chain loci that undergo rearrangement and are expressed in B cells to produce xenogenous immunoglobulin, resulting in the production of xenogenous antibodies against said one or more antigens; and
(b) recovering said xenogenous antibodies from said ungulate.
27. A method of producing xenogenous antibodies against one or more antigens, said method comprising recovering xenogenous antibodies from a transgenic ungulate whose cells comprise one or more artificial chromosomes, each artificial chromosome comprising one or more xenogenous immunoglobulin heavy or light chain loci that undergo rearrangement and are expressed in B cells, resulting in production of xenogenous antibodies against said one or more antigens.
28. The method of claim 26 or 27 , wherein said xenogenous immunoglobulin is human immunoglobulin.
29. The method of claim 26 or 27 , wherein said immunoglobulin loci comprise both a human immunoglobulin light chain locus and a human immunoglobulin heavy chain locus.
30. The method of claim 26 or 27 , wherein said one or more artificial chromosomes comprise a chromosome fragment.
31. The method of claim 30 , wherein said artificial chromosome is a YAC or BAC.
32. The method of claim 26 or 27 , wherein said artificial chromosome is a human artificial chromosome.
33. The method of claim 32 , wherein said human artificial chromosome is a ΔHAC or ΔΔHAC.
34. The method of claim 32 , wherein said human artificial chromosome is derived from one or more of human chromosome 14, human chromosome 2, and human chromosome 22.
35. The method of claim 26 or 27 , wherein said ungulate is a bovine, ovine, porcine, or caprine.
36. The method of claim 35 , wherein said ungulate is a porcine.