Genetically modified major histocompatibility complex animals
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
(a) at a first endogenous major histocompatibility complex (MHC) II gene locus a first and second nucleotide sequence, each respectively encoding a first chimeric human/mouse MHC II α polypeptide and a first chimeric human/mouse MHC II β polypeptide, and each respectively expressed under regulatory control of endogenous MHC II α and β promoters at the first endogenous MHC II gene locus,
wherein the first chimeric human/mouse MHC II α polypeptide comprises α1 and α2 extracellular domains of an α polypeptide of a first human MHC II complex and transmembrane and cytoplasmic domains of an α polypeptide of a first endogenous mouse MHC II complex,
wherein the first chimeric human/mouse MHC II β polypeptide comprises β1 and β2 extracellular domains of a β polypeptide of the first human MHC II complex and transmembrane and cytoplasmic domains of a β polypeptide of the first endogenous mouse MHC II complex, and
(b) at a second endogenous MHC II locus a third and fourth nucleotide sequence, each respectively encoding a second chimeric human/mouse MHC II α polypeptide and a second chimeric human/mouse MHC II β polypeptide, and each respectively expressed under regulatory control of endogenous MHC II α and β promoters at the second endogenous MHC II gene locus,
wherein the second chimeric human/mouse MHC II α polypeptide comprises α1 and α2 extracellular domains of an α polypeptide of a second human MHC II complex and transmembrane and cytoplasmic domains of an α polypeptide of a second endogenous mouse MHC II complex,
wherein the second chimeric human/mouse MHC II beta polypeptide comprises β1 and β2 extracellular domains of a β polypeptide of the second human MHC II complex and transmembrane and cytoplasmic domains of a β polypeptide of the second endogenous mouse MHC II complex, and
wherein the mouse expresses the first chimeric human/mouse MHC II α and β polypeptides as a first chimeric human/mouse MHC II complex and the second chimeric human/mouse MHC II α and β polypeptides as a second chimeric human/mouse MHC II complex on the surface of an antigen presenting cell.
2. 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 at the first endogenous MHC II locus,
wherein the second nucleotide sequence is expressed under regulatory control of endogenous mouse MHC II β promoter and regulatory elements at the first endogenous MHC II locus,
wherein the third nucleotide sequence is expressed under regulatory control of endogenous mouse MHC II α promoter and regulatory elements at the second MHC II locus, and
wherein the fourth nucleotide sequence is expressed under regulatory control of endogenous mouse MHC II β promoter and regulatory elements at the second endogenous MHC II locus.
3. The mouse of claim 1 , wherein the first and/or the second human MHC II complex is a human leukocyte antigen (HLA) class II protein selected from the group consisting of HLA-DR, HLA-DQ, and HLA-DP.
4. The mouse of claim 3 , wherein the first human MHC II complex is a human HLA-DR protein.
5. The mouse of claim 4 , wherein the first human MHC II complex is a human HLA-DR2 or a human HLA-DR4 protein.
6. The mouse of claim 4 , wherein the second human MHC complex is a human HLA-DQ protein.
7. The mouse of claim 6 , wherein the second human MHC complex is a human HLA-DQ2 or a human HLA-DQ8 protein.
8. The mouse of claim 1 , wherein the mouse does not express, on the surface of the antigen presenting cell, endogenous MHC II polypeptides from endogenous mouse MHC II loci.
9. The mouse of claim 1 , wherein the antigen presenting cell is a dendritic cell, macrophage, or CD19 + B cell.
10. The mouse of claim 1 , wherein the first and/or the second human MHC II complex is a human leukocyte antigen (HLA) class II protein selected from the group consisting of HLA-DR4, HLA-DR2, HLA-DQ2, and HLA-DQ8.
11. The mouse of claim 1 , wherein the first and/or the second endogenous mouse MHC II complex is selected the group consisting of from H-2A and H-2E.
12. The mouse of claim 1 , wherein the first and/or the second chimeric MHC II complex is selected from the group consisting of HLA-DR4/H-2E, HLA-DR2/H-2E, HLA-DQ2/H-2A, and HLA-DQ8/H-2A.
13. The mouse of claim 1 , wherein the first and second human MHC II complexes are different.