Genetically modified major histocompatibility complex mice
The invention provides genetically modified non-human animals that express a humanized MHC II protein (humanized MHC II α and β polypeptides), as well as embryos, cells, and tissues comprising the humanized MHC II protein. Also provided are constructs for and methods of making the genetically modified non-human animals. Methods of using the genetically modified non-human animals to study various aspects of the human immune system are provided.
1. A mouse comprising at an endogenous Major Histocompatibility Complex (MHC) II gene locus a first nucleotide sequence encoding a chimeric human/mouse MHC II α polypeptide and a second nucleotide sequence encoding a chimeric human/mouse MHC II β polypeptide,
wherein a human portion of the chimeric human/mouse MHC II α polypeptide comprises a human MHC II α2 domain and a human portion of the chimeric human/mouse MHC II β polypeptide comprises a human MHC II β2 domain,
wherein the first nucleotide sequence is expressed under regulatory control of an MHC II α promoter, and the second nucleotide sequence is expressed under regulatory control of an MHC II β promoter, and
wherein the mouse expresses the chimeric human/mouse MHC II α and β polypeptides on the surface of an antigen presenting cell of the mouse.
2. The mouse of claim 1 , wherein the chimeric human/mouse MHC II α polypeptide further comprises a human α1 domain.
3. The mouse of claim 1 , wherein the chimeric human/mouse MHC II β polypeptide further comprises a human β1 domain.
4. The mouse of claim 1 , wherein the first nucleotide sequence is expressed under regulatory control of endogenous mouse MHC II α promoter and regulatory elements, and the second nucleotide sequence is expressed under regulatory control of endogenous mouse MHC II β promoter and regulatory elements.
5. The mouse of claim 1 , wherein a mouse portion of the chimeric human/mouse MHC II α polypeptide comprises transmembrane and cytoplasmic domains of an endogenous mouse MHC II α polypeptide.
6. The mouse of claim 1 , wherein a mouse portion of the chimeric human/mouse MHC II β polypeptide comprises transmembrane and cytoplasmic domains of an endogenous mouse MHC II β polypeptide.
7. The mouse of claim 1 , wherein the human portion of the chimeric human/mouse MHC II α polypeptide is encoded by a Human Leukocyte Antigen (HLA) class II gene selected from the group consisting of any α chain gene of HLA-DR, HLA-DQ, and HLA-DP; and wherein the human portion of the chimeric human/mouse MHC β polypeptide is encoded by a HLA class II gene selected from the group consisting of any β chain gene of HLA-DR, HLA-DQ, and HLA-DP.
8. The mouse of claim 7 , wherein the human portion of the chimeric human/mouse MHC II α polypeptide is encoded by a human HLA-DRA gene and the human portion of the chimeric human/mouse MHC II β polypeptide is encoded by a human HLA-DRB1*04 gene.
9. The mouse of claim 1 , wherein the mouse portion of the chimeric human/mouse MHC II α polypeptide comprises cytoplasmic and transmembrane domains from a mouse H-2E α polypeptide, and the mouse portion of the chimeric human/mouse MHC II β polypeptide comprises cytoplasmic and transmembrane domains from a mouse H-2E β polypeptide.
10. The mouse of claim 1 , wherein the mouse does not express functional endogenous MHC II polypeptides from their endogenous mouse MHC II loci.
11. A mouse comprising at an endogenous mouse Major Histocompatibility Complex (MHC) II locus a first nucleotide sequence encoding a chimeric human/mouse MHC II α polypeptide and a second nucleotide sequence encoding a chimeric human/mouse MHC II β polypeptide,
wherein a human portion of the chimeric MHC II α polypeptide comprises a human α2 domain encoded by a human HLA-DRA gene and the human portion of the chimeric MHC II β polypeptide comprises a human β2 domain encoded by a human HLA-DRB gene,
wherein a mouse portion of the chimeric MHC II α polypeptide comprises transmembrane and cytoplasmic domains of a mouse H-2E α chain and a mouse portion of the chimeric MHC II β polypeptide comprises transmembrane and cytoplasmic domains of a mouse H-2E β chain,
wherein the first nucleotide sequence is expressed under regulatory control of an MHC II α promoter and the second nucleotide sequence is expressed under regulatory control of an MHC II β promoter,
and wherein the mouse expresses a chimeric HLA-DR/H-2E MHC II polypeptide on the surface of an antigen presenting cell of the mouse.
12. The mouse of claim 11 , wherein the extracellular domain of the α polypeptide further comprises a human α1 domain encoded by a human HLA-DRA gene.
13. The mouse of claim 11 , wherein the extracellular domain of the β polypeptide further comprises a human β1 domain encoded by a human HLA-DRB gene.
14. The mouse of claim 11 , wherein the first nucleotide sequence is expressed under regulatory control of endogenous mouse MHC II α promoter and regulatory elements, and the second nucleotide sequence is expressed under regulatory control of endogenous mouse MHC II β promoter and regulatory elements.
15. The mouse of claim 11 , wherein the mouse does not express functional endogenous MHC II polypeptides from their endogenous mouse loci.
16. The mouse of claim 11 , wherein the mouse expresses a chimeric HLA-DR4/H-2E MHC II polypeptide.