Soluble heterodimeric CD94/NKG2 receptors fusion proteins
Soluble versions of heterodimeric receptors, e.g., CD94/NKG2 receptors, and methods of producing and using such constructs, are described. The constructs comprise soluble fragments of, each receptor monomer, and some constructs further comprise at least one immunoglobulin Fc domain. Exemplary constructs are those wherein (1) each soluble fragment is linked to an immunoglobulin Fc domain, which are then allowed to dimerize, (2) each soluble fragment is linked to an immunoglobulin Fc domain mutated to promote forced dimerization with the correct counterpart, and (3) single-chain constructs where the monomeric receptor fragments are linked, and the C-terminal fragment is linked to an Fc domain.
1. A soluble CD94/NKG2 receptor fusion protein comprising a soluble portion of an NKG2 amino acid sequence and a soluble portion of a CD94 amino acid sequence wherein said fusion protein binds HLA-E.
2. The soluble CD94/NKG2 receptor fusion protein of claim 1 , further comprising an immunoglobulin polypeptide comprising all or part of an Fc domain or variant thereof.
3. The soluble CD94/NKG2 receptor fusion protein of claim 2 , wherein the C-terminal of the soluble portion of a CD94 amino acid sequence is linked to the N-terminal of the soluble portion of an NKG2 amino acid sequence, and the C-terminal of the soluble portion of an NKG2 amino acid sequence is linked to the immunoglobulin polypeptide.
4. The soluble CD94/NKG2 receptor fusion protein of claim 2 , wherein the C-terminal of the soluble portion of an NKG2 amino acid sequence is linked to the N-terminal of the soluble portion of a CD94 amino acid sequence, and the C-terminal of the soluble portion of a CD94 amino acid sequence is linked to the immunoglobulin polypeptide.
5. The soluble CD94/NKG2 receptor fusion protein of claim 3 , wherein the soluble portion of an NKG2 amino acid sequence and soluble portion of a CD94 amino acid sequence are linked by a peptide linker comprising glycine and serine.
6. The soluble CD94/NKG2 receptor fusion protein of claim 1 , which is a CD94/NKG2A, CD94/NKG2B, CD94/NKG2C, CD94/NKG2E, or CD94/NKG2F receptor fusion protein.
7. The soluble CD94/NKG2 receptor fusion protein of claim 6 , which is CD94/NKG2A.
8. The soluble CD94/NKG2A receptor fusion protein of claim 7 , comprising residues 99-233 of SEQ ID NO: 1.
9. The soluble CD94/NKG2 receptor fusion protein of claim 6 , which is CD94/NKG2C.
10. The soluble CD94/NKG2C receptor fusion protein of claim 9 , comprising residues 96-231 of SEQ ID NO: 3.
11. The soluble CD94/NKG2 receptor fusion protein of claim 1 , comprising residues 35-179 of SEQ ID NO: 2.
12. A soluble CD94/NKG2A receptor fusion protein comprising the sequence of any one of SEQ ID NOS: 37-39.
13. A dimer of the soluble CD94/NKG2 receptor fusion protein of claim 1 .
14. A method of producing a soluble CD94/NKG2 receptor fusion protein, comprising culturing a cell comprising a nucleic acid encoding the soluble CD94/NKG2 receptor fusion protein of claim 1 under conditions suitable for expression of the soluble CD94/NKG2 receptor fusion protein.
15. A composition comprising the soluble CD94/NKG2 receptor fusion protein of claim 1 and a pharmaceutically acceptable carrier or excipient.
16. The soluble CD94/NKG2 receptor fusion protein of claim 4 , wherein the soluble portion of an NKG2 amino acid sequence and soluble portion of a CD94 amino acid sequence are linked by a peptide linker comprising glycine and serine.
17. A dimer of the soluble CD94/NKG2 receptor fusion protein of claim 7 .
18. A dimer of the soluble CD94/NKG2 receptor fusion protein of claim 8 .
19. A composition comprising the soluble CD94/NKG2 receptor fusion protein of claim 12 and a pharmaceutically acceptable carrier or excipient.
20. A method of producing a soluble CD94/NKG2 receptor fusion protein, comprising culturing a cell comprising a nucleic acid encoding the soluble CD94/NKG2 receptor fusion protein of claim 12 under conditions suitable for expression of the soluble CD94/NKG2 receptor fusion protein.