ANTIBODY PRODUCING NON-HUMAN ANIMALS
Described are transgenic, non-human animals comprising a nucleic acid encoding an immunoglobulin light chain, whereby the immunoglobulin light chain is human, human-like, or humanized. The nucleic acid is provided with a means that renders it resistant to DNA rearrangements and/or somatic hypermutations. In one embodiment, the nucleic acid comprises an expression cassette for the expression of a desired molecule in cells during a certain stage of development in cells developing into mature B cells. Further provided is methods for producing an immunoglobulin from the transgenic, non-human animal.
1 . A B cell that produces an antibody that binds to a desired antigen, which B cell is isolated from a transgenic non-human animal that has been immunized with the antigen, wherein the genome of said animal comprises a transgene encoding a rearranged human immunoglobulin variable region and wherein the transgene comprises an immunoglobulin constant region or said rearranged human immunoglobulin variable region is operatively linked to an endogenous immunoglobulin constant region, and wherein the transgenic animal has produced a repertoire of antibodies that bind said antigen having the rearranged human immunoglobulin variable region encoded by the rearranged human immunoglobulin variable region comprised in said transgene.
2 . The B cell of claim 1 , wherein the transgene encoding a rearranged human immunoglobulin variable region comprises a human germline light chain V gene segment joined to a human germline light chain J gene segment, wherein there is no mutation due to said joining and wherein said immunoglobulin constant region is a light chain constant region.
3 . The B cell of claim 1 , wherein the transgene encoding a rearranged human immunoglobulin variable region comprises a human germline heavy chain V gene segment joined to a human germline heavy chain D gene segment joined to a human heavy chain J gene segment, wherein there is no mutation due to said joining and wherein said immunoglobulin constant region is a heavy chain constant region.
4 . The B cell of claim 1 wherein the transgenic animal is a mammal.
5 . The B cell of claim 1 wherein the transgenic animal is a rodent.
6 . The B cell of claim 5 wherein the transgenic animal is a mouse.
7 . The B cell of claim 1 wherein, in said antibodies, the rearranged variable region is encoded by the transgene that has not undergone somatic hypermutation.
8 . A method to obtain an antibody that binds to an antigen, the method comprising culturing the B cell of claim 1 to obtain a population of said B cells and recovering antibodies secreted by said B cells.
9 . A method to obtain an antibody that binds to an antigen, the method comprising culturing the B cell of claim 2 to obtain a population of said B cells and recovering antibodies secreted by said B cells.
10 . A method to obtain an antibody that binds to an antigen, the method comprising culturing the B cell of claim 3 to obtain a population of said B cells and recovering antibodies secreted by said B cells.
11 . A method to obtain an antibody or fragment thereof that binds to an antigen, the method comprising
(a) isolating nucleic acid comprising nucleotide sequences encoding the antibody secreted by the B cell of claim 1 ;
(b) transfecting recombinant host cells with expression system(s) for production of the antibody or fragment encoded by the nucleotide sequences contained in the nucleic acid obtained in step (a);
(c) culturing said host cells, and
(d) recovering the antibodies or fragments secreted by the host cells.
12 . Recombinant host cells that comprise nucleic acids that express nucleotide sequences encoding the antibody secreted by the B cell of claim 1 or an antigen-binding fragment thereof.
13 . A method to obtain an antibody or fragment thereof that binds to an antigen which method comprises culturing the cells of claim 12 under conditions wherein said nucleotide sequences are expressed and recovering said antibody or fragment.
14 . A method to obtain an antibody or fragment thereof that binds to an antigen, the method comprising
(a) isolating nucleic acid comprising nucleotide sequences encoding the antibody secreted by the B cell of claim 2 ;
(b) transfecting recombinant host cells with expression system(s) for production of the antibody or fragment encoded by the nucleotide sequences contained in the nucleic acid obtained in step (a);
(c) culturing said host cells, and
(d) recovering the antibodies or fragments secreted by the host cells.
15 . Recombinant host cells that comprise nucleic acids that express nucleotide sequences encoding the antibody secreted by the B cell of claim 2 or an antigen-binding fragment thereof.
16 . A method to obtain an antibody or fragment thereof that binds to an antigen which method comprises culturing the cells of claim 15 under conditions wherein said nucleotide sequences are expressed and recovering said antibody or fragment.
17 . A method to obtain an antibody or fragment thereof that binds to an antigen, the method comprising
(a) isolating nucleic acid comprising nucleotide sequences encoding the antibody secreted by the B cell of claim 3 ;
(b) transfecting recombinant host cells with expression system(s) for production of the antibody or fragment encoded by the nucleotide sequences contained in the nucleic acid obtained in step (a);
(c) culturing said host cells, and
(d) recovering the antibodies or fragments secreted by the host cells.
18 . Recombinant host cells that comprise nucleic acids that express nucleotide sequences encoding the antibody secreted by the B cell of claim 3 or an antigen-binding fragment thereof.
19 . A method to obtain an antibody or fragment thereof that binds to an antigen which method comprises culturing the cells of claim 18 under conditions wherein said nucleotide sequences are expressed and recovering said antibody or fragment.
20 . A recombinant expression system which system is a nucleic acid comprising a nucleotide sequence encoding at least a variable region of an antibody secreted by the B cell of claim 1 , operatively linked to control sequences for expression.
21 . A recombinant expression system which system is a nucleic acid comprising a nucleotide sequence encoding at least a variable region of an antibody secreted by the B cell of claim 2 , operatively linked to control sequences for expression.
22 . A recombinant expression system which system is a nucleic acid comprising a nucleotide sequence encoding at least a variable region of an antibody secreted by the B cell of claim 3 , operatively linked to control sequences for expression.