Specific interleukin-15 (IL-15) antagonist polypeptide and uses thereof for the treatment of inflammatory and auto-immune diseases
The present invention relates to specific interleukin-15 (IL-15) antagonist polypeptides and uses thereof for the treatment of inflammatory and auto-immune diseases. In particular, the present invention relates to a specific interleukin-15 (IL-15) antagonist polypeptide comprising i) a IL15-Ralpha sushi-containing polypeptide comprising an amino acid sequence having at least 80% of identity with the amino acid sequence of SEQ ID NO:1 ii) a linker and iii) an IL-polypeptide comprising the amino acid sequence having at least at least 80% of identity with the amino acid sequence of SEQ ID NO:4 provided that the glutamine (Q) residue at position 108 is mutated.
1. A polypeptide comprising the polypeptide of SEQ ID NO:5 or SEQ ID NO:6, having
an IL15-Ralpha sushi-containing polypeptide,
a linker, and
an IL-15 polypeptide wherein the residue at position 108 in the IL-15 polypeptide is not a glutamine (Q).
2. The polypeptide of claim 1 , which is fused to an immunoglobulin domain.
3. The polypeptide of claim 2 , wherein the immunoglobulin domain is an immunoglobulin constant domain (Fc region).
4. A pharmaceutical composition comprising the polypeptide of claim 1 .