Re-targeted toxin conjugates

A method of designing a non-cytotoxic toxin conjugate for inhibition or reduction of exocytic fusion in a target cell, comprising:

• (a) identifying an agonist that increases exocytic fusion in said target cell;
• and
• (b) preparing an agent, said agent comprising:
• (i) a targeting moiety that binds the agent to a binding site on said target cell, said binding site undergoes endocytosis to be incorporated into an endosome within the target cell, and wherein the targeting moiety is an agonist identifiable by step (a);
• (ii) a non-cytotoxic protease or a fragment thereof, said protease or protease fragment is capable of cleaving a protein of the exocytic fusion apparatus of said target cell;
• and
• (iii) a translocation domain that translocates the protease or protease fragment from within the endosome, across the endosomal membrane, and into the cytosol of the target cell.

A method of designing a non-cytotoxic toxin conjugate for inhibition or reduction of exocytic fusion in a target cell, comprising:

• (a) identifying an agonist that increases exocytic fusion in said target cell;
• and
• (b) preparing an agent, said agent comprising:
• (i) a targeting moiety that binds the agent to a binding site on said target cell, said binding site undergoes endocytosis to be incorporated into an endosome within the target cell, and wherein the targeting moiety is an agonist identifiable by step (a);
• (ii) a DNA sequence encoding a non-cytotoxic protease or a fragment thereof, said DNA sequence is expressible in the target cell and when so expressed provides a protease or protease fragment capable of cleaving a protein of the exocytic fusion apparatus of said target cell;
• and
• (iii) a translocation domain that translocates the DNA sequence encoding the protease or protease fragment from within the endosome, across the endosomal membrane, and into the cytosol of the target cell.

A pharmaceutical composition, comprising an agent, said agent comprising:

• (a) a targeting moiety that binds the agent to a binding site on a target cell, said binding site undergoes endocytosis to be incorporated into an endosome within the target cell, and wherein the targeting moiety is an agonist that is capable of increasing exocytic fusion in the target cell;
• (b) a non-cytotoxic protease or a fragment thereof, said protease or protease fragment is capable of cleaving a protein of the exocytic fusion apparatus of said target cell;
• and
• (c) a translocation domain that translocates the protease or protease fragment from within the endosome, across the endosomal membrane, and into the cytosol of the target cell.

A pharmaceutical composition, comprising an agent, said agent comprising:

• (a) a targeting moiety that binds the agent to a binding site on a target cell, said binding site undergoes endocytosis to be incorporated into an endosome within the target cell, and wherein the targeting moiety is an agonist that is capable of increasing exocytic fusion in the target cell;
• (b) a DNA sequence encoding a non-cytotoxic protease or a fragment thereof, said DNA sequence is expressible in the target cell and when so expressed provides a protease or protease fragment capable of cleaving a protein of the exocytic fusion apparatus of said target cell;
• and
• (c) a translocation domain that translocates the protease or protease fragment from within the endosome, across the endosomal membrane, and into the cytosol of the target cell.