Fusion proteins targeting tumour associated macrophages for treating cancer

Abstract

The present invention relates to cancer immunotherapy. In particular, provided herein are fusion proteins for targeting tumor associated macrophages with immunostimulatory agents.

We claim: 
     
         1 . A fusion protein for targeting of tumor-associated macrophages comprising:
 i) a targeting unit that specifically binds to a protein selected from the group consisting of CD206, FOLR2, LGMN, CD204, CD163, and CD301; and   ii) an IL-15 polypeptide.   
     
     
         2 . The fusion protein of  claim 1 , wherein the targeting unit is an antigen binding protein that specifically binds to said CD206. 
     
     
         3 . The fusion protein of  claim 1 , wherein the targeting unit is an antigen binding protein that specifically binds to FOLR2. 
     
     
         4 . The fusion protein of  claim 1 , wherein said antigen binding protein is selected from the group consisting of an immunoglobulin single variable domain and a single chain variable fragment (scFv). 
     
     
         5 . The fusion protein of  claim 3 , wherein said immunoglobulin single variable domain is a nanobody. 
     
     
         6 . The fusion protein of  claim 5 , wherein said nanobody binds to CD206. 
     
     
         7 . The fusion protein of  claim 5 , wherein said nanobody binds to FOLR2. 
     
     
         8 . The fusion protein of  claim 1 , wherein the targeting unit and the IL-15 polypeptide are connected by a linker. 
     
     
         9 . A nucleic acid encoding the fusion protein of  claim 1 . 
     
     
         10 . A host cell comprising the nucleic acid of  claim 9 . 
     
     
         11 . A method of inducing a cancer specific immune response, comprising:
 administering the fusion protein of  claim 1  to a subject diagnosed with cancer under conditions such that said subject generates or amplifies an immune response to cancer cells in said subject.