Animal models and therapeutic molecules
The invention discloses methods for the generation of chimaeric human-nonhuman antibodies and chimaeric antibody chains, antibodies and antibody chains so produced, and derivatives thereof including fully humanised antibodies; compositions comprising the disclosed antibodies, antibody chains and derivatives, as well as cells, non-human mammals and vectors, suitable for use in the disclosed methods.
1. A transgenic mouse having a genome comprising a homozygous recombinant immunoglobulin light chain (IgL) locus,
said locus comprising unrearranged human V region light chain gene segments comprising the functional V and J gene segments from Vλ2-18 to Cλ7 of a human λ light chain locus, wherein said unrearranged human V region light chain gene segments are positioned
(i) at an endogenous mouse immunoglobulin light chain locus comprising an endogenous enhancer and
(ii) upstream of a constant region,
said recombinant light chain locus being functional to rearrange to express an immunoglobulin light chain comprising a human V region,
wherein said recombinant immunoglobulin light chain locus comprises human Vλ and Jλ gene segments,
wherein said mouse comprises splenic B cells expressing immunoglobulin light chains comprising λ variable regions,
wherein a plurality of said immunoglobulin light chains comprises a plurality of human λ variable regions,
wherein said mouse comprises immunoglobulin gamma antibody comprising λ variable regions, and wherein the mouse expresses more immunoglobulin light chain comprising a human Vλ region than immunoglobulin light chain comprising a mouse Vλ region,
wherein said mouse exhibits usage of human Jλ gene segments in splenic B cells that is typical of the usage of J λ segments in splenic B cells of humans, or wherein said mouse exhibits usage of human V λ gene segments in splenic B cells typical of the usage of Vλ gene segments in splenic B cells of humans or both.
2. The mouse of claim 1 , wherein at least 60, 80, 84, 85, 90, 95, 96, 97, 98, or 99%, or 100% of immunoglobulin light chains expressed by said mouse comprise human V regions derived from recombination of human Vλ and Jλ gene segments.
3. The mouse of claim 1 , said immunoglobulin λ light chains comprise a repertoire of human λ variable regions.
4. The mouse of claim 1 , wherein said unrearranged human V region light chain gene segments comprise a 3′ human V segment which is positioned within 100 kb of said endogenous light chain locus enhancer.
5. The mouse of claim 1 , wherein said endogenous enhancer comprises a λ enhancer.
6. The mouse of claim 5 , wherein said endogenous enhancer is in germline order relative to an endogenous constant region.
7. The mouse of claim 1 , wherein said endogenous enhancer comprises a κ enhancer.
8. The mouse of claim 7 , wherein said endogenous enhancer comprises an iEκ sequence enhancer or a 3′ Eκ sequence enhancer, or both.
9. The mouse of claim 1 , wherein the genome comprises endogenous V light chain DNA comprising endogenous Vλ chain DNA.
10. The mouse of claim 1 , wherein the genome comprises endogenous V light chain DNA comprising endogenous V κ chain DNA.
11. The mouse of claim 1 , wherein the unrearranged human V light chain gene segment is positioned upstream to a lambda light chain constant region.
12. The mouse of claim 1 , wherein at least 80% of the immunoglobulin light chains that comprise λ variable regions expressed in said mouse comprise human λ variable regions.
13. The mouse of claim 1 said mouse being functional to produce progeny.
14. The mouse of claim 1 , wherein said human Vλ gene segments and Jλ gene segments are positioned upstream of an endogenous constant κ region, wherein said mouse does not comprise endogenous κ immunoglobulin light chain wherein said mouse comprises B cells which comprise immunoglobulin comprising human λ variable region to immunoglobulin comprising mouse λ variable region at a ratio of 80:15.
15. The mouse of claim 14 , wherein said genome as a whole retains endogenous light chain V region DNA.
16. The mouse of claim 14 , wherein 84% of light chains of total splenic B cells grouped as B220/CD45R positive of said mouse comprise human λ variable regions.
17. The mouse of claim 14 , wherein said genome comprises an endogenous λ light chain locus functional to express endogenous λ light chain.
18. The mouse of claim 1 , wherein said human Vλ gene segments and Jλ gene segments are positioned upstream of an λ constant region, and wherein said mouse does not comprise immunoglobulin comprising an endogenous κ immunoglobulin light chain,
wherein B cells of said mouse comprise immunoglobulin comprising human λ variable region relative to immunoglobulin comprising mouse λ variable region at a ratio of 93:5,
wherein in said mouse, the ratio of splenic mature and immature B cells of said mouse are typical of the ratio of splenic mature and immature B cells of a mouse comprising a genome nonfunctional to encode endogenous kappa immunoglobulin light chain.
19. The mouse of claim 18 , wherein 93% of total splenic B cells grouped as B220/CD45R positive of said mouse comprise human λ variable regions.
20. The mouse of claim 1 , wherein said immunoglobulin gamma comprising human Vλ regions comprises antigen specific human Vλ.
21. The mouse of claim 1 , wherein said human Vλ segments and Jλ segments are positioned upstream to a κ constant region.
22. The mouse of claim 1 , wherein said unrearranged human V light chain gene segments are operatively associated with said endogenous enhancer at said endogenous light chain locus.
23. The mouse of claim 1 , wherein said mouse comprises splenic B cells which express said IgG.