Non-human animals having a humanized signal-regulatory protein gene
Genetically modified non-human animals and methods and compositions for making and using the same are provided, wherein the genetic modification comprises a humanization of an endogenous signal-regulatory protein gene, in particular a humanization of a SIRPα gene. Genetically modified mice are described, including mice that express a human or humanized SIRPα protein from an endogenous SIRPα locus.
1. A mouse whose genome comprises a replacement of exons 2, 3and 4 of a mouse SIRPα gene at an endogenous mouse SIRPα locus with exons 2, 3 and 4 of a human SIRPα gene to form a humanized SIRPα gene, wherein said humanized SIRPα gene is operably linked to a mouse SIRPα promoter at said endogenous mouse SIRPα locus, and expresses in said mouse a humanized SIRPα protein comprising an extracellular portion of the human SIRPα protein encoded by said human SIRPα gene and an intracellular portion of the mouse SIRPα protein encoded by said mouse SIRPα gene.
2. The mouse of claim 1 , wherein said humanized SIRPα protein is expressed on the cell surface in said mouse and supports the engraftment of human CD34+ hematopoietic stem cells.
3. The mouse of claim 1 , wherein the mouse does not express a mouse SIRPα protein.
4. The mouse of claim 1 , wherein the humanized SIRPα gene comprises exons 1, 5, 6, 7 and 8 of said mouse SIRPα gene.
5. The mouse of claim 4 , wherein said human SIRPα protein comprises the amino acid sequence as set forth in SEQ ID NO: 4.
6. The mouse of claim 5 , wherein the extracellular portion of said human SIRPα protein comprises amino acid residues 28-362 of said human SIRPα protein.
7. The mouse of claim 4 , wherein said humanized SIRPα protein is expressed on the cell surface in said mouse and supports the engraftment of human CD34+ hematopoietic stem cells.
8. The mouse of claim 4 , wherein the mouse does not express a mouse SIRPα protein.
9. The mouse of claim 1 , wherein said human SIRPα protein comprises the amino acid sequence as set forth in SEQ ID NO:4.
10. The mouse of claim 9 , wherein the extracellular portion of said human SIRPα protein comprises amino acid residues 28-362 of said human SIRPα protein.
11. The mouse of claim 9 , wherein the mouse does not express a mouse SIRPα protein.
12. An isolated mouse cell or tissue whose genome comprises a replacement of exons 2, 3 and 4 of a mouse SIRPα gene at an endogenous mouse SIRPα locus with exons 2, 3 and 4 of a human SIRPα gene to form a humanized SIRPα gene, wherein said humanized SIRPα gene is operably linked to a mouse SIRPα promoter at said endogenous mouse SIRPα locus, and expresses in said mouse cell or tissue a humanized SIRPα protein comprising an extracellular portion of the human SIRPα protein encoded by said human SIRPα gene and an intracellular portion of the mouse SIRPα protein encoded by said mouse SIRPα gene.
13. The isolated cell or tissue of claim 12 , wherein the humanized SIRPα gene comprises exons 1, 5, 6, 7 and 8 of said mouse SIRPα gene.
14. The isolated cell or tissue of claim 12 , wherein the cell or tissue does not express a mouse SIRPα protein.
15. The isolated cell or tissue of claim 12 , wherein the cell or tissue is an embryonic stem cell.
16. A mouse embryo generated from the embryonic stem cell of claim 15 .