Compositions and Methods for Treating Elevated Secretory Activity

Abstract

Methods for treating diseases characterized by elevated secretory activity using a protease directed to a non-neuronal SNARE protein are described. The protease is produced by selective mutation of a botulinum neurotoxin light chain, and is characterized utilizing a reporting construct that includes all or part of the non-neuronal SNARE protein. Such a protease has utility in the treatment of diseases associated with hypersecretion, where the hypersecretion is mediated by a non-neuronal SNARE protein.

What is claimed is: 
     
         1 . A method of treating an individual having a disease characterized by an elevated secretory activity, comprising:
 providing a pharmaceutical comprising a synthetic peptide having a protease activity characterized by substrate specificity for a non-neuronal SNARE protein having an exosite, wherein the protease comprises a mutation of a wild-type  botulinum  toxin light chain, wherein the mutation comprises a non-native exosite recognition sequence that interacts with the exosite of the non-neuronal SNARE protein, and wherein the mutation is selected to provide improved binding between the protease and the non-neuronal SNARE protein relative to a neuronal SNARE protein that acts as a substrate for the wild-type  botulinum  toxin light chain; and   administering the pharmaceutical to the individual on a schedule effective to reduce the secretory activity.   
     
     
         2 . The method of  claim 1 , wherein the synthetic peptide comprises a targeting moiety. 
     
     
         3 . The method of  claim 2 , wherein the targeting moiety binds to cells or tissues associated with the secretory activity. 
     
     
         4 . The method of  claim 2 , wherein the targeting moiety supports binding of the synthetic peptide to a cell and transportation to the cell interior. 
     
     
         5 . The method of  claim 2 , wherein the targeting moiety is selected from the group consisting of an antibody, and antibody fragment, a receptor ligand, a pharmaceutical compound, a microparticle, and an aptamer. 
     
     
         6 . The method of  claim 1 , wherein the wild-type  botulinum  toxin light chain is selected from the group consisting of  botulinum  neurotoxin serotype A (BoNT/A) light chain,  botulinum  neurotoxin serotype B (BoNT/B) light chain,  botulinum  neurotoxin serotype C (BoNT/C) light chain,  botulinum  neurotoxin serotype D (BoNT/D) light chain,  botulinum  neurotoxin serotype E (BoNT/E) light chain,  botulinum  neurotoxin serotype F (BoNT/F) light chain, and  botulinum  neurotoxin serotype G (BoNT/G) light chain. 
     
     
         7 . The method of  claim 1 , wherein the non-native exosite recognition sequence comprises one or more mutations to sites corresponding to one or more of the group consisting of Asn136, Ser143, Glu148, Val304, Thr176, His227, Lys337, Leu256, Val258, and Lys356 of SEQ ID NO. 4. 
     
     
         8 . The method of  claim 7 , wherein the mutation of Asn 136 is selected from the group consisting of Ala, Arg, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr, and Val. 
     
     
         9 . The method of  claim 7 , wherein the mutation of Ser143 is selected from the group consisting of Asp and Glu. 
     
     
         10 . The protease of  claim 7 , wherein the mutation of Glu148 is selected from the group consisting of Met and Val. 
     
     
         11 . The method of  claim 7 , wherein the mutation of Val304 is selected from the group consisting of Asp and Glu. 
     
     
         12 . The method of  claim 7 , wherein the mutation of Thr176 is selected from the group consisting of Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Lys, Met, Phe, Pro, Ser, Trp, Tyr, and Val. 
     
     
         13 . The method of  claim 7 , wherein the mutation of His 227 is selected from the group consisting of Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, Ile, Leu, Lys, Met, Phe, Pro, Ser, Thr, Trp, Tyr, and Val. 
     
     
         14 . The method of  claim 7 , wherein the mutation of Lys337 is selected from the group consisting of Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Met, Phe, Pro, Ser, Thr, Trp, Tyr, and Val. 
     
     
         15 . The method of  claim 7 , wherein the mutation of Leu256 is selected from the group consisting of Asp, Ala, and Gly. 
     
     
         16 . The method of  claim 7 , wherein the mutation of Val258 is selected from the group consisting of Asp, Ala, and Gly. 
     
     
         17 . The method of  claim 7 , wherein the mutation of Lys356 is selected from the group consisting of Ala, Arg, Asn, Asp, Cys, Glu, Gln, Gly, His, Ile, Leu, Met, Phe, Pro, Ser, Thr, Trp, Tyr, and Val. 
     
     
         18 . The method of  claim 1 , wherein the non-neuronal SNARE protein is selected from the group consisting of SNAP-23 and SNAP-29.