Tear lipocalin muteins binding IL-4 r alpha
The present invention relates to novel muteins derived from human tear lipocalin, which bind to IL 4 receptor alpha. The sequences of the muteins comprise particular combinations of amino acids. In particular a mutated amino acid residue is present at any one or more of the sequence positions 27, 28 30, 31, 33, 53, 57, 61, 64, 66, 80, 83, 104-106 and 108 of the linear polypeptide sequence of the mature human tear lipocalin. A mutated amino acid residue is also present at any 2 or more of the sequence positions 26, 32, 34, 55, 56, 58 and 63 of the linear polypeptide sequence of the mature human tear lipocalin. The invention also provides a corresponding nucleic acid molecule encoding such a mutein and a method for producing such a mutein and its encoding nucleic acid molecule.
1. A mutein of human tear lipocalin having binding affinity to interleukin (IL)-4 receptor alpha, wherein the mutein has at least 90% identity to an amino acid sequence set forth in SEQ ID NO: 6.
2. The mutein of claim 1 , wherein the mutein has at least 95% identity to an amino acid sequence set forth in SEQ ID NO: 6.
3. The mutein of claim 1 , wherein the mutein has at least 98% identity to an amino acid sequence set forth in SEQ ID NO: 6.
4. The mutein of claim 1 , wherein the mutein has at least 99% identity to an amino acid sequence set forth in SEQ ID NO: 6.
5. The mutein of claim 4 , wherein the mutein binds to human IL-4 receptor alpha with a dissociation constant (K D ) of below 0.1 nM.
6. The mutein of claim 4 , wherein the mutein binds to human IL-4 receptor alpha with a dissociation constant (K D ) of below 0.05 nM.
7. The mutein of claim 4 , wherein the mutein binds to human IL-4 receptor alpha with a dissociation constant (K D ) of below 0.03 nM.
8. The mutein of claim 4 , wherein the mutein is an IL-4 antagonist and/or an IL-13 antagonist.
9. The mutein of claim 4 , wherein the mutein inhibits IL-4 and/or IL-13 induced cell proliferation.
10. The mutein of claim 4 , wherein the mutein inhibits IL-4 induced TF-1 cell proliferation with an IC 50 of about 5 nM or lower.
11. The mutein of claim 4 , wherein the mutein inhibits IL-13 induced TF-1 cell proliferation with an IC 50 value of about 10 nM or lower.
12. A fusion protein comprising the mutein of claim 4 .
13. A nucleic acid molecule comprising a nucleotide sequence encoding the mutein of claim 4 .
14. A host cell containing the nucleic acid molecule of claim 4 .
15. A pharmaceutical or a diagnostic composition comprising the mutein of claim 4 .