Human chondroitinase glycoprotein (CHASEGP), process for preparing the same, and pharmaceutical compositions comprising thereof

Abstract

The invention relates to the discovery of a novel Chondroitinase Glycoproteins (CHASEGPs), methods of manufacture, and potential uses in conditions where removal of chondroitin sulfates may be of therapeutic benefit. Chondroitinase Glycoproteins require both a substantial portion of the catalytic domain of the CHASEGP polypeptide and asparagine-linked glycosylation for optimal chondroitinase activity. The invention also includes carboxy-terminal deletion variants of CHASEGP that result in secreted variants of the protein to facilitate manufacture of a recombinant CHASEGP. Further described are suitable formulations of a substantially purified recombinant CHASEGP glycoprotein derived from a eukaryotic cell that generate the proper glycosylation required for its optimal activity. CHASEGP is useful for the degradation of glycosaminoglycans and chondroitin sulfate proteoglycans under clinical conditions where their removal is of therapeutic value.

1 . A substantially purified soluble mammalian chondroitinase glycoprotein (CHASEGP) polypeptide, consisting of the sequence of amino acid residues set forth in SEQ ID NO:6 or a sequence of amino acids that has at least 96% sequence identity to the polypeptide consisting of the sequence of amino acid residues set forth in SEQ ID NO:6, wherein the CHASEGP polypeptide is soluble and has chondroitinase activity. 
     
     
         2 . The glycoprotein of  claim 1 , wherein a sugar moiety is covalently attached to an asparagine residue selected from the group consisting of amino acid residues 52, 81 and 309 as set forth in SEQ ID NO:6. 
     
     
         3 . The glycoprotein of  claim 2 , wherein said sugar moiety is covalently linked to said glycoprotein through a asparagine peptide specific N-glycosidase F (PNGase) sensitive bond. 
     
     
         4 . The glycoprotein of  claim 2 , wherein said sugar moiety is of the high mannose type. 
     
     
         5 . The glycoprotein of  claim 2 , wherein said sugar moiety is of the complex type. 
     
     
         6 . The glycoprotein of  claim 2 , wherein said sugar moiety is of the hybrid type. 
     
     
         7 . The glycoprotein of  claim 2 , wherein said sugar moiety is substantially terminated with sialic acid. 
     
     
         8 . The glycoprotein of  claim 1 , wherein the CHASEGP is a human polypeptide. 
     
     
         9 . The glycoprotein of  claim 1 , wherein the polypeptide is encoded by a nucleic acid sequence as set forth in SEQ ID NO. 5. 
     
     
         10 . The glycoprotein of  claim 1 , wherein the polypeptide further comprises one or more domains selected from a polyhistidine domain, protein A domain, FLAG domain, Factor XA domain, an enterokinase domain, or a combination thereof. 
     
     
         11 . A composition comprising the CHASEGP of  claim 1  in a pharmaceutically acceptable carrier. 
     
     
         12 . A method for treating a subject suffering from an excess of CHASEGP substrate, comprising administering the glycoprotein of  claim 1  to the subject in an amount sufficient to remove said CHASEGP substrate. 
     
     
         13 . The method of  claim 12 , wherein excess CHASEGP substrate results from scar tissue. 
     
     
         14 . The method of  claim 13 , wherein the scar tissue is a glial scar resulting from spinal surgery. 
     
     
         15 . The method of  claim 13 , wherein the scar tissue is a result of surgery. 
     
     
         16 . The method of  claim 13  wherein the scar is a keloid scar. 
     
     
         17 . A method for treating a subject suffering from an excess of CHASEGP substrate associated with a herniated disk comprising administering the glycoprotein of  claim 1  to the subject in an amount sufficient to remove the CHASEGP substrate.