TGFbeta type II-type III receptor fusions

Abstract

Certain embodiments are directed to novel heterotrimeric fusions in which the ectodomain of the TGF-β type II receptor (TβP?II) is coupled to the N- and C-terminal ends of the endoglin-domain of the TGF-β type III receptor (TpRIIIE). Certain embodiments are directed to novel heterotrimeric polypeptides in which the ectodomain of the TGF-β type II receptor (TI3RII) is coupled to the N- and C-terminal ends of the endoglin-domain (E domain) of the TGF-β type III receptor (TI3RIII). This trimeric receptor, known as RER, can bind all three TGF-β isoforms with sub-nanomolar affinity and is effective at neutralizing signaling induced by all three TGF-β isoforms, but not other ligands of the TGF-β superfamily, such as activins, growth and differentiation factors (GDFs), and bone morphonogenetic proteins (BMPs).

The invention claimed is: 
     
       1. A TGFβ-binding heterotrimeric fusion protein wherein the fusion protein has an amino acid sequence that is 90% identical to SEQ ID NO: 2. 
     
     
       2. The fusion protein of  claim 1 , further comprising an amino terminal signal sequence. 
     
     
       3. The fusion protein of  claim 1 , further comprising an amino terminal or carboxy terminal tag. 
     
     
       4. The fusion protein of  claim 3 , wherein the tag is a carboxy terminal hexa-histidine. 
     
     
       5. A method of treating a condition related to increased expression TGFβ comprising administering an effective amount of the fusion protein of  claim 1  to subject in thereof. 
     
     
       6. The method of  claim 5 , wherein the condition is a hyperproliferative disorder. 
     
     
       7. The method of  claim 6 , wherein the hyperproliferative disorder is cancer. 
     
     
       8. The method of  claim 5 , wherein the condition is fibrosis. 
     
     
       9. A heterotrimeric fusion protein wherein the fusion protein has the amino acid sequence of SEQ ID NO:2. 
     
     
       10. The fusion protein of  claim 9 , further comprising an amino terminal signal sequence. 
     
     
       11. The fusion protein of  claim 9 , further comprising an amino terminal or carboxy terminal tag. 
     
     
       12. The fusion protein of  claim 11 , wherein the tag is a carboxy terminal hexa-Histidine. 
     
     
       13. A fusion protein comprising, in the N-terminal to C-terminal direction:
 (i) a first portion having an amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO: 3;   (ii) a second portion having an amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO: 4; and   (iii) a third portion having an amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO: 5.   
     
     
       14. The fusion protein of claim 13, wherein the first portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 3. 
     
     
       15. The fusion protein of claim 13, wherein the second portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 4. 
     
     
       16. The fusion protein of claim 13, wherein the third portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 5. 
     
     
       17. The fusion protein of claim 13, wherein the first portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 3, the second portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 4, and the third portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 5. 
     
     
       18. The fusion protein of claim 13, wherein the first portion has the amino acid sequence of SEQ ID NO: 3. 
     
     
       19. The fusion protein of claim 13, wherein the second portion has the amino acid sequence of SEQ ID NO: 4. 
     
     
       20. The fusion protein of claim 13, wherein the third portion has the amino acid sequence of SEQ ID NO: 5. 
     
     
       21. The fusion protein of claim 13, wherein the first portion has the amino acid sequence of SEQ ID NO: 3, the second portion has the amino acid sequence of SEQ ID NO: 4, and the third portion has the amino acid sequence of SEQ ID NO: 5. 
     
     
       22. The fusion protein of claim 13, wherein either or both of (i) the first portion and the second portion, and (ii) the second portion and the third portion are joined to one another by way of a polypeptide linker. 
     
     
       23. The fusion protein of claim 13, further comprising an amino terminal or carboxy terminal tag. 
     
     
       24. A nucleic acid encoding the fusion protein of claim 13. 
     
     
       25. The nucleic acid of claim 24, wherein the first portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 3. 
     
     
       26. The nucleic acid of claim 24, wherein the second portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 4. 
     
     
       27. The nucleic acid of claim 24, wherein the third portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 5. 
     
     
       28. The nucleic acid of claim 24, wherein the first portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 3, the second portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 4, and the third portion has an amino acid sequence that is at least 95% identical to the amino acid sequence of SEQ ID NO: 5. 
     
     
       29. The nucleic acid of claim 24, wherein the first portion has the amino acid sequence of SEQ ID NO: 3. 
     
     
       30. The nucleic acid of claim 24, wherein the second portion has the amino acid sequence of SEQ ID NO: 4. 
     
     
       31. The nucleic acid of claim 24, wherein the third portion has the amino acid sequence of SEQ ID NO: 5. 
     
     
       32. The nucleic acid of claim 24, wherein the first portion has the amino acid sequence of SEQ ID NO: 3, the second portion has the amino acid sequence of SEQ ID NO: 4, and the third portion has the amino acid sequence of SEQ ID NO: 5. 
     
     
       33. The nucleic acid of claim 24, wherein either or both of (i) the first portion and the second portion, and (ii) the second portion and the third portion are joined to one another by way of a polypeptide linker. 
     
     
       34. The nucleic acid of claim 24, wherein the fusion protein further comprises an amino terminal or carboxy terminal tag. 
     
     
       35. A vector comprising the nucleic acid of claim 24. 
     
     
       36. A host cell comprising the nucleic acid of claim 24. 
     
     
       37. A host cell comprising the vector of claim 35. 
     
     
       38. A method of producing the fusion protein of claim 13, the method comprising contacting a host cell with a nucleic acid encoding the fusion protein and subsequently isolating the fusion protein from the host cell. 
     
     
       39. A pharmaceutical composition comprising the fusion protein of claim 13 and one or more pharmaceutically acceptable excipients. 
     
     
       40. The pharmaceutical composition of claim 39, wherein the composition is formulated for administration to a human subject. 
     
     
       41. The pharmaceutical composition of claim 40, wherein the composition is formulated for parenteral, subcutaneous, intravenous, intramuscular, or intraperitoneal administration to the human subject. 
     
     
       42. A method of reducing or preventing binding of TGF-β to one or more endogenous TGF-β receptors in a subject, the method comprising administering to the subject the fusion protein of claim 13. 
     
     
       43. The method of claim 42, wherein the subject is a human.