Platlet glycoprotein Ib alpha fusion polypeptides and methods of use thereof

Abstract

The present invention provides compositions and methods for treating or preventing vascular-associated disorders.

1 . A fusion polypeptide comprising a first polypeptide operably linked to a second polypeptide, wherein the first polypeptide comprises at least a region of a glycoprotein Ibα polypeptide and the second polypeptide comprises at least a region of an immunoglobulin polypeptide.  
     
     
         2 . The fusion polypeptide of  claim 1 , wherein said first polypeptide includes an extracellular portion of a membrane glycoprotein Ibα polypeptide.  
     
     
         3 . The fusion polypeptide of  claim 2 , wherein said first polypeptide binds to one or more of the polypeptides selected from the group consisting of a leukocyte integrin Mac-1 polypeptide, von Willebrand factor, thrombin and P-selectin.  
     
     
         4 . The fusion polypeptide of  claim 3 , wherein said first polypeptide is at least 85% homologous to SEQ ID NO:1.  
     
     
         5 . The fusion polypeptide of  claim 1 , wherein said polypeptide comprises SEQ ID NO:1.  
     
     
         6 . The fusion polypeptide of  claim 1 , wherein said first polypeptide is more resistant to proteolysis than a wild-type GP Ibα1 polypeptide.  
     
     
         7 . The fusion polypeptide of  claim 1 , wherein said first polypeptide binds with higher affinity to a von Willibrand factor polypeptide than a wild-type glycoprotein Ibα polypeptide binds to said von Willibrand factor polypeptide.  
     
     
         8 . The fusion polypeptide of  claim 7 , wherein said first polypeptide comprises at least one of the amino acid substitutions G233V or M239V relative to the amino acid sequence of a wild-type GPIb α polypeptide.  
     
     
         9 . The fusion polypeptide of  claim 7 , wherein said first polypeptide comprises the amino acid substitutions G233V and M239V relative to the amino acid sequence of a wild-type GPIb α1 polypeptide  
     
     
         10 . The fusion polypeptide of  claim 1 , wherein said second polypeptide comprises a region of a heavy chain immunoglobulin polypeptide.  
     
     
         11 . The fusion polypeptide of  claim 10 , wherein said second polypeptide comprises an Fc region of an immunoglobulin heavy chain.  
     
     
         12 . The fusion polypeptide of  claim 11 , herein said second polypeptide has less effector function than the effector function of a Fc region of a wild-type immunoglobulin heavy chain.  
     
     
         13 . The fusion polypeptide of  claim 12 , wherein said second polypeptide binds with low or no affinity to a Fc receptor.  
     
     
         14 . The fusion polypeptide of  claim 12 , wherein said second polypeptide binds with low or no affinity to complement protein C1q.  
     
     
         15 . The fusion polypeptide of  claim 2 , wherein said second polypeptide comprises a region of a heavy chain immunoglobulin polypeptide.  
     
     
         16 . The fusion polypeptide of  claim 15 , wherein said second polypeptide comprises an Fc region of an immunoglobulin heavy chain.  
     
     
         17 . The fusion polypeptide of  claim 15 , wherein said second polypeptide has less effector function than the effector function of a Fc region of a wild-type immunoglobulin heavy chain.  
     
     
         18 . The fusion polypeptide of  claim 17 , wherein said second polypeptide binds with low or no affinity to a Fc receptor.  
     
     
         19 . The fusion polypeptide of  claim 17 , wherein said second polypeptide binds with low or no affinity to complement protein C1q.  
     
     
         20 . The fusion polypeptide of  claim 1 , wherein said fusion polypeptide comprises the amino acid sequence of GP1b302-Ig (SEQ ID NO:1), Gp1b302/2A-Ig (SEQ ID NO:2), GP1b302/4X-Ig (SEQ ID NO:3), GP1b290 Ig (SEQ ID NO:4), GPIb290/2V-Ig (SEQ ID NO:5.) and GPIb290/1A-Ig (SEQ ID NO:6.).  
     
     
         21 . A multimeric polypeptide comprising the fusion polypeptide of  claim 1 .  
     
     
         22 . The multimeric polypeptide of  claim 21 , wherein said multimeric polypeptide is a dimer.  
     
     
         23 . A DNA molecule encoding the fusion polypeptide of  claim 1 .  
     
     
         24 . A vector comprising the DNA of  claim 21 .  
     
     
         25 . A cell comprising the vector of  claim 22 .  
     
     
         26 . A method for expressing glycoprotein Ibα polypeptide-immunoglobulin fusion polypeptide, the method comprising culturing the cell of  claim 25  under conditions that result in expression of said glycoprotein Ibα polypeptide-immunoglobulin fusion polypeptide.  
     
     
         27 . A pharmaceutical composition comprising the fusion polypeptide of  claim 1 .  
     
     
         28 . A pharmaceutical composition comprising the nucleic acid of  claim 23 .  
     
     
         29 . A method of inhibiting adherence of a blood cell to a biological tissue in a biological system, the method comprising adding to said biological system the fusion polypeptide of  claim 1  in an amount sufficient to inhibit adherence of said blood cell to said biological tissue.  
     
     
         30 . The method of  claim 29 , wherein said biological system is an in vitro system.  
     
     
         31 . The method of  claim 29 , wherein said biological system is an ex vivo system.  
     
     
         32 . The method of  claim 29 , wherein said biological system is an in vivo system.  
     
     
         33 . The method of  claim 29 , wherein said blood cell is a platelet.  
     
     
         34 . The method of  claim 33 , wherein said platelet express glycoprotein Ib α, P-selectin or thrombin.  
     
     
         35 . The method of  claim 29 , wherein said blood cell is a leukocyte.  
     
     
         36 . The method of  claim 35 , wherein said leukocyte express Mac-1 or a selectin ligand.  
     
     
         37 . The method of  claim 29 , wherein said biological tissue is complexed with von Willibrand Factor or thrombin, glycoprotein Ib α, or P-selectin.  
     
     
         38 . A method of inhibiting adherence of a protein to a biological tissue in a biological system, the method comprising adding to said biological system the fusion polypeptide of  claim 1  in an amount sufficient to inhibit adherence of said protein to said biological tissue.  
     
     
         39 . The method of  claim 38 , wherein said biological system is an in vitro system.  
     
     
         40 . The method of  claim 38 , wherein said biological system is an ex vivo system.  
     
     
         41 . The method of  claim 38 , wherein said biological system is an in vivo system.  
     
     
         42 . The method of  claim 38 , wherein said protein is membrane associated.  
     
     
         43 . The method of  claim 42 , wherein said protein is glycoprotein Ibα, P-selectin, von Willibrand Factor or thrombin.  
     
     
         44 . The method of  claim 38 , wherein said protein is in solution.  
     
     
         45 . The method of  claim 44 , wherein said protein is von Willibrand Factor or thrombin.  
     
     
         46 . The method of  claim 38 , wherein said biological tissue is complexed with a protein selected from the group consisting of glycoprotein Ibα, Mac-1, P-selectin, von Willibrand Factor and thrombin.  
     
     
         47 . A method of treating a disorder associated with platelet activation in a subject, the method comprising administering to a subject in need thereof the fusion polypeptide of  claim 1 .  
     
     
         48 . The method of  claim 47 , wherein said disorder is associated with thrombotic disease.  
     
     
         49 . The method of  claim 47 , wherein said disorder is ischemic heart disease, angina, acute myocardial infarction, stroke, venous thrombosis, atherosclerosis, or arterial thrombosis.  
     
     
         50 . The method of  claim 47 , wherein said disorder is angina.  
     
     
         51 . The method of  claim 50 , wherein said angina is unstable angina.  
     
     
         52 . The method of  claim 47 , wherein said subject is a human.  
     
     
         53 . The method of  claim 47 , further comprising administering to said subject a compound selected from the group consisting of acetylsalicylic acid, heparin, a glycoprotein IIb/IIIa antagonist, clopidogrel, a P-selectin antagonist, a thrombin inhibitor and a thrombolytic enzyme.