Patent ID: 7674470

Claim:
An antigenic composition comprising a single chain polypeptide comprising first and second domains, wherein: said first domain is a clostridial neurotoxin light chain or a variant thereof, or a fragment of said light chain or variant wherein said variant or fragment has a common antigenic cross-reactivity to said clostridial neurotoxin light chain; and said second domain is a clostridial neurotoxin heavy chain H N portion or a variant thereof, or a fragment of said heavy chain H N portion or variant wherein said variant or fragment has a common antigenic cross-reactivity to said clostridial neurotoxin heavy chain H N portion; and wherein said second domain is capable of (i) translocating the polypeptide into a cell or (ii) increasing the solubility of the polypeptide compared to the solubility of the first domain on its own or (iii) both translocating the polypeptide into a cell and increasing the solubility of the polypeptide compared to the solubility of the first domain on its own; and wherein the second domain lacks a functional C-terminal part of a clostridial neurotoxin heavy chain designated H C thereby rendering the polypeptide incapable of binding to cell surface receptors that are the natural cell surface receptors to which native clostridial neurotoxin binds.