Common light chain mouse

Abstract

A genetically modified mouse is provided, wherein the mouse is incapable of rearranging and expressing an endogenous mouse immunoglobulin light chain variable sequence, wherein the mouse expresses only one or two human light chain variable domains encoded by human immunoglobulin sequences operably linked to the mouse kappa (κ) constant gene at the endogenous mouse κ locus, wherein the mouse expresses a reverse chimeric antibody having a light chain variable domain derived from one of only two human light chain variable region gene segments and a mouse κ constant domain, and a human heavy chain variable domain and a mouse heavy chain constant domain, from an endogenous mouse heavy chain locus. Bispecific epitope-binding proteins that are fully human are provided, comprising two different heavy chains that associate with an identical light chain that comprises a variable domain derived from one of two different human light chain variable region gene segments.

1 .- 21 . (canceled) 
     
     
         22 . A targeting vector comprising:
 (i) a 5′ homology arm comprising a nucleotide sequence corresponding to a genomic target sequence that is upstream to a 5′-most mouse Vκ gene segment in an unmodified endogenous mouse kappa light chain locus;   (ii) a selection marker;   (iii) a Vκ promoter sequence,   (iv) a single rearranged immunoglobulin light chain Vκ/Jκ sequence, wherein the single rearranged immunoglobulin light chain Vκ/Jκ sequence comprises a human Vκ1-39 or a human Vκ3-20; and   (v) a 3′ homology arm comprising a nucleotide sequence corresponding to a genomic target sequence that is downstream of an endogenous mouse Jκ5 gene segment in an unmodified endogenous mouse kappa light chain locus, wherein the 3′ homology arm comprises a mouse Cκ exon.   
     
     
         23 . The targeting vector of  claim 22 , wherein the single rearranged light chain Vκ/Jκ sequence is a Vκ1-39/Jκ5 sequence. 
     
     
         24 . The targeting vector of  claim 23 , wherein the Vκ1-39/Jκ5 sequence is as set forth in nucleotides 2362 through 2686 of SEQ ID NO: 1. 
     
     
         25 . The targeting vector of  claim 22 , wherein the single rearranged light chain Vκ/Jκ sequence is a Vκ3-20/Jκ1 sequence. 
     
     
         26 . The targeting vector of  claim 25 , wherein the Vκ3-20/Jκ1 sequence is as set forth in nucleotides 2373 through 2697 of SEQ ID NO: 11. 
     
     
         27 . The targeting vector of  claim 22 , wherein the Vκ promoter sequence is a Vκ3-15 promoter sequence. 
     
     
         28 . The targeting vector of  claim 22 , wherein the targeting vector further comprises a Vκ3-7 leader sequence. 
     
     
         29 . A host cell comprising:
 (a) a first nucleic acid sequence that encodes a first immunoglobulin heavy chain, the first nucleic acid sequence comprising a first human immunoglobulin heavy chain variable region sequence that was identified from a B cell of a first mouse, wherein the first mouse has been immunized with a first antigen of interest including a first epitope, wherein the first human immunoglobulin heavy chain variable region sequence encodes a first human immunoglobulin heavy chain variable domain that recognizes the first epitope, and wherein the first mouse comprises in its germline genome:
 (i) an engineered mouse immunoglobulin kappa light chain locus comprising: a Vκ promoter sequence, a single rearranged immunoglobulin light chain Vκ/Jκ sequence comprising a human Vκ1-39 or a human Vκ3-20, and a mouse Cκ sequence, and 
 (ii) human immunoglobulin variable region gene segments operably linked to a mouse immunoglobulin heavy chain constant region sequence at the endogenous heavy chain loci; and 
   (b) a second nucleic acid sequence that encodes an immunoglobulin light chain comprising a human immunoglobulin kappa light chain variable region sequence comprising the single rearranged immunoglobulin light chain Vκ/Jκ sequence, or a somatically hypermutated version thereof.   
     
     
         30 . The host cell of  claim 29 , wherein the single rearranged light chain Vκ/Jκ sequence is a Vκ1-39/Jκ5 sequence. 
     
     
         31 . The host cell of  claim 29 , wherein the single rearranged light chain Vκ/Jκ sequence is a Vκ3-20/Jκ1 sequence. 
     
     
         32 . The host cell of  claim 29 , wherein the Vκ promoter sequence is a Vκ3-15 promoter sequence. 
     
     
         33 . The host cell of  claim 29 , wherein the engineered mouse immunoglobulin kappa light chain locus further comprises a Vκ3-7 leader sequence 
     
     
         34 . The host cell of  claim 29 , further comprising a third nucleic acid sequence that encodes a second immunoglobulin heavy chain comprising a second human immunoglobulin heavy chain variable region sequence that was identified from a B cell of a second mouse, wherein the second mouse has been immunized with a second antigen of interest including a second epitope, wherein the second human immunoglobulin heavy chain variable region sequence encodes a second human immunoglobulin heavy chain variable domain that recognizes the second epitope, and wherein the second mouse comprises in its germline genome:
 (i) an engineered mouse immunoglobulin kappa light chain locus comprising: a Vκ promoter sequence, the single rearranged immunoglobulin light chain Vκ/Jκ sequence, and a mouse Cκ sequence, and   (ii) human immunoglobulin variable region gene segments operably linked to a mouse immunoglobulin heavy chain constant region sequence at the endogenous heavy chain loci; and   wherein the first and the second immunoglobulin heavy chains pair with the immunoglobulin light chain encoded by the second nucleic acid sequence.   
     
     
         35 . A method for making an antibody comprising:
 expressing in a single cell:
 (a) a first nucleic acid sequence that encodes a first immunoglobulin heavy chain, the first nucleic acid sequence comprising a first human immunoglobulin heavy chain variable region sequence that was identified from a B cell of a first mouse, and wherein the first mouse has been immunized with a first antigen of interest including a first epitope, wherein the first human immunoglobulin heavy chain variable region sequence encodes a first human immunoglobulin heavy chain variable domain that recognizes the first epitope, and wherein the first mouse comprises in its germline genome:
 (i) an engineered mouse immunoglobulin kappa light chain locus comprising: a Vκ promoter sequence, a single rearranged immunoglobulin light chain Vκ/Jκ sequence comprising a human Vκ1-39 or a human Vκ3-20, and a mouse Cκ sequence, and 
 (ii) human immunoglobulin variable region gene segments operably linked to a mouse immunoglobulin heavy chain constant region sequence at the endogenous heavy chain loci; and 
 
 (b) a second nucleic acid sequence that encodes an immunoglobulin light chain, the second nucleic acid sequence comprising a human immunoglobulin kappa light chain variable region sequence comprising the single rearranged immunoglobulin light chain Vκ/Jκ sequence, or a somatically hypermutated version thereof, 
   maintaining the cell under conditions sufficient to express the antibody; and   isolating the antibody.   
     
     
         36 . The method of  claim 35 , wherein the single rearranged light chain Vκ/Jκ sequence is a Vκ1-39/Jκ5 sequence. 
     
     
         37 . The method of  claim 35 , wherein the single rearranged light chain Vκ/Jκ sequence is a Vκ3-20/Jκ1 sequence. 
     
     
         38 . The method of  claim 35 , wherein the Vκ promoter sequence is a Vκ3-15 promoter sequence. 
     
     
         39 . The method of  claim 35 , wherein the engineered mouse immunoglobulin kappa light chain locus further comprises a Vκ3-7 leader sequence 
     
     
         40 . The method of  claim 35 , wherein the cell comprises a third nucleic acid sequence that encodes a second immunoglobulin heavy chain comprising a second human immunoglobulin heavy chain variable region sequence that was identified from a B cell of a second mouse, and wherein the second mouse has been immunized with a second antigen of interest including a second epitope, wherein the second immunoglobulin heavy chain variable region sequence encodes a second human immunoglobulin heavy chain variable domain that recognizes the second epitope, and wherein the second mouse comprises in its germline genome:
 (i) an engineered mouse immunoglobulin kappa light chain locus comprising: a Vκ promoter sequence, the single rearranged immunoglobulin light chain Vκ/Jκ sequence, and a mouse Cκ sequence, and   (ii) human immunoglobulin variable region gene segments operably linked to a mouse immunoglobulin heavy chain constant region sequence at the endogenous heavy chain loci, and   wherein the first and the second immunoglobulin heavy chains pair with the immunoglobulin light chain encoded by the second nucleic acid sequence.   
     
     
         41 . The method of  claim 40 , wherein the first and the second immunoglobulin heavy chains are fully human immunoglobulin heavy chains and the immunoglobulin light chain is a fully human immunoglobulin light chain.