Interleukin-2 muteins for the expansion of T-regulatory cells
Provided herein are IL-2 muteins and IL-2 mutein Fc-fusion molecules that preferentially expand and activate T regulatory cells and are amenable to large scale production. Also provided herein are variant human IgG1 Fc molecules lacking or with highly reduced effector function and high stability despite lacking glycosylation at N297. Also, provided herein are linker peptides that are glycosylated when expressed in mammalian cells.
1. An Fc-fusion protein comprising a Fc region and a human interleukin-2 (IL-2) mutein, wherein the mutein comprises a V91K substitution and an amino acid sequence having at least 95% identity to the amino acid sequence of SEQ ID NO:1, and further wherein the Fc region comprises a substitution at N297, using Eu numbering scheme, and an amino acid sequence having at least 95% identity to the amino acid sequence of SEQ ID NO:3, wherein said Fc-fusion protein preferentially stimulates T regulatory cells.
2. The Fc-fusion protein of claim 1 , wherein the Fc is a human IgG Fc.
3. The Fc-fusion protein of claim 2 , wherein the human IgG Fc is a human IgG1 Fc.
4. The Fc-fusion protein of claim 1 , wherein the substitution at N297 is N297G.
5. The Fc-fusion protein of claim 2 , comprising a substitution or deletion of the C-terminal lysine of said human IgG Fc.
6. The Fc-fusion protein of claim 5 , wherein the C-terminal lysine of said human IgG Fc is deleted.
7. The Fc-fusion protein of claim 1 , wherein a linker connects the Fc region and human IL-2 mutein of said protein.
8. The Fc-fusion protein of claim 7 , wherein the linker is GGGGS (SEQ ID NO: 5), GGNGT (SEQ ID NO: 6), or YGNGT (SEQ ID NO: 7).
9. The Fc-fusion protein of claim 8 , wherein the linker is GGGGS (SEQ ID NO: 5).
10. The Fc-fusion protein of claim 1 , wherein said Fc-fusion protein comprises an Fc dimer.
11. The Fc-fusion protein of claim 10 , wherein said Fc-fusion protein comprises two IL-2 muteins.
12. The Fc-fusion protein of claim 10 , wherein said Fc-fusion protein comprises a single IL-2 mutein.
13. The Fc-fusion protein of claim 1 , wherein the amino acid sequence of said Fc-fusion protein comprises the amino acid sequence of SEQ ID NO:17 or SEQ ID NO:18.
14. The Fc-fusion protein of claim 13 , wherein the amino acid sequence of said Fc-fusion protein consists of the amino acid sequence of SEQ ID NO:17 or SEQ ID NO:18.
15. The Fc-fusion protein of claim 1 , wherein the human IL-2 mutein further comprises a substitution at position 125.
16. The Fc-fusion protein of claim 15 , wherein the substitution at position 125 is to an alanine residue.
17. The Fc-fusion protein of claim 15 , wherein the substitution at position 125 is to a serine residue.
18. The Fc-fusion protein of claim 15 , wherein the Fc is a human IgG Fc.
19. The Fc-fusion protein of claim 15 , wherein the human IgG Fc is a human IgG1 Fc.
20. The Fc-fusion protein of claim 18 , comprising a substitution or deletion of the C-terminal lysine of said human IgG Fc.
21. The Fc-fusion protein of claim 20 , wherein the C-terminal lysine of said human IgG Fc is deleted.
22. The Fc-fusion protein of claim 15 , wherein a linker connects the Fc region and human IL-2 mutein of said protein.
23. The Fc-fusion protein of claim 22 , wherein the linker is GGGGS (SEQ ID NO: 5), GGNGT (SEQ ID NO: 6), or YGNGT (SEQ ID NO: 7).
24. The Fc-fusion protein of claim 23 , wherein the linker is GGGGS (SEQ ID NO: 5).
25. The Fc-fusion protein of claim 15 , wherein said Fc-fusion protein comprises an Fc dimer.
26. The Fc-fusion protein of claim 25 , wherein said Fc-fusion protein comprises two IL-2 muteins.
27. The Fc-fusion protein of claim 25 , wherein said Fc-fusion protein comprises a single IL-2 mutein.