Non-human transgenic mammal for the constant region of the class a human immunoglobulin heavy chain and applications thereof

• US 8,629,317 B2
• Filed: 10/21/2004
• Issued: 01/14/2014
• Est. Priority Date: 10/24/2003
• Status: Active Grant

• Current Assignee: Centre National De La Recherche Scientifique, Universite de Limoges
• Original Assignee: Centre National De La Recherche Scientifique, Universite de Limoges
• Inventors: Cogne, Michel, Sirac, Christophe, Bardel, Micael, Decourt, Catherine, Le Morvan, Caroline
• Primary Examiner(s): LI, QIAN JANICE
• Application Number:
  US10/577,061
• Publication Number:
  US 20070248601A1
• Time in Patent Office: 3,372 Days
• Field of Search: None
• US Class Current: 800/13
• CPC Class Codes: A01K 2207/15 Humanized animals
• CPC Class Codes: A01K 2217/00 Genetically modified animals
• CPC Class Codes: A01K 2227/105 Murine
• CPC Class Codes: A01K 2267/01 Animal expressing industrially exogenous proteins
• CPC Class Codes: A01K 67/0278 Knock-in vertebrates, e.g. humanised vertebrates
• CPC Class Codes: A61P 31/00 Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
• CPC Class Codes: A61P 35/00 Antineoplastic agents
• CPC Class Codes: C07K 16/18 against material from animals or humans
• CPC Class Codes: C07K 2317/21 from primates, e.g. man
• CPC Class Codes: C07K 2317/24 containing regions, domains or residues from different species, e.g. chimeric, humanized or veneered
• CPC Class Codes: C12N 15/8509 for producing genetically modified animals, e.g. transgenic
• CPC Class Codes: C12N 2800/30 Vector systems comprising sequences for excision in presence of a recombinase, e.g. loxP or FRT

Abstract

The invention relates to a non-human transgenic mammal with an IgH locus modified by replacement of the switching sequence Sμ with all or part of a transgene comprising the gene Cα of a class A human immunoglobulin, including at least the exon, coding for the CH3 domain and the membrane exon and the applications of the above for the production of humanized class IgA antibodies.

Claims

1. A transgenic mouse, wherein an endogenous IgH locus comprises replacement of its switch sequence Sμ

with a transgene consisting essentially of a human class A immunoglobulin heavy chain constant region gene Cα

or a segment of said Cα

gene comprising at least an exon encoding the CH3 domain and a membrane exon, wherein said transgenic mouse produces chimeric immunoglobulins A whose heavy chains comprise a mouse variable region and a human constant region or a segment thereof comprising at least the CH3 domain, and wherein said transgenic mouse produces no mouse immunoglobulins M.

2. The transgenic mouse of claim 1, which is homozygous for said modified IgH locus.

3. The transgenic mouse of claim 1, wherein said transgene consists of the entire Cα

gene.

4. The transgenic mouse of claim 1, wherein said transgene consists of the segment of the Cα

gene comprising the exon encoding the CH3 domain and the membrane exon.

5. The transgenic mouse of claim 1, wherein said Cα

gene is the Cα

1 gene.

6. The transgenic mouse of claim 1, which further comprises another transgene encoding a human immunoglobulin light chain.

7. The transgenic mouse of claim 6, wherein said light chain is a kappa light chain.

8. The transgenic mouse of claim 6, wherein said transgene which encodes a human immunoglobulin kappa light chain, further comprises the intronic activator Eμ

upstream of a DNA sequence encoding said human immunoglobulin kappa light chain and the palindrome hs3a/hs1,2/hs3b downstream of said DNA sequence.

9. The transgenic mouse of claim 8, wherein said transgene is under the control of the promoter of the human immunoglobulin heavy chain.

10. The transgenic mouse of claim 6, which is dizygous for said transgene.

11. The transgenic mouse of claim 6, further comprising an inactivated endogenous immunoglobulin kappa light chain locus.

12. The transgenic mouse of claim 11, which is homozygous for said inactivated endogenous immunoglobulin kappa light chain locus.

13. The transgenic mouse of claim 1, further comprising an inactivated endogenous J chain gene.

14. The transgenic mouse of claim 13, which is homozygous for said inactivated endogenous J chain gene.

15. The transgenic mouse of claim 13, which further comprises another transgene encoding a human immunoglobulin J chain gene.

16. The transgenic mouse of claim 1, wherein said:

a) endogenous mouse IgH locus comprises the replacement of its switch sequence Sμ

with the entire human class A immunoglobulin heavy chain constant region gene Cα

1, and

b) which transgenic mouse further comprises a human kappa light chain transgene comprising a Vκ

I gene rearranged with a Jκ

5 gene, a Jκ

-Cκ

intron and a Cκ

gene, under the transcriptional control of the human heavy chain promoter (pVH), the intronic activator Eμ

upstream of said promoter of and the palindrome hs3a/hs1,2/hs3b downstream of said Cκ

gene.

22. A method for preparing humanized class IgA antibodies or fragments thereof, which comprises at least the following steps:

a) immunizing the transgenic mouse of claim 1, and

b) producing humanized class IgA antibodies or fragments of the antibodies from serum secretions or B lymphocytes of said transgenic mouse sacrificed beforehand.

17. A homologous recombination targeting vector, which comprises a human class A immunoglobulin heavy chain constant region gene Cα

or a segment of said Cα

gene comprising at least an exon encoding the CH3 domain and a membrane exon, flanked by the sequences SEQ ID NO;

7 and SEQ ID NO;

8.

18. The targeting vector of claim 17, which comprises a cassette for expressing a selection marker, adjacent to said Cα

gene or to a segment of said gene.

19. The targeting vector of claim 18, wherein said expression cassette is flanked by site-specific recombination sequences.

20. The targeting vector of claim 19 wherein said sequences are LoxP sequences of Cre recombinase.

21. A mouse embryonic cell, which is modified with the targeting vector of claim 17.