Targeted delivery of a SNARE protease to sensory neurons using a single chain antibody (scFv) against the extracellular domain of P2X3 inhibits the release of a pain mediator

The P2X purinoceptor 3 (P2X3) is predominantly expressed on nociceptive sensory neurons and plays a crucial role in signaling leading to chronic inflammatory pain and some features of neuropathic pain. Thus, it provides a potential target for pain therapeutics.Botulinum toxin type A (BoNT/A) effectively relieves certain types of pain through inhibiting the neuronal release of pain peptides. Recombinant single-chain variable fragment, scFv, was generated against the extracellular domain of P2X3, using phage display technology. The genes encoding the scFv and BoNT/A without N-terminal binding domain (LC-HN-HCN/A) were ligated and expressed in E. coli as an activated di-chain form. The purified protein bound and entered P2X3-containing sensory neurons, cleaved synaptosomal-associated protein 25, and inhibited the release of a pain peptide. This novel fusion protein LC-HN-HCN/A-MH7C has potential clinical applications in the treatment of chronic inflammatory and sympathetically maintained neuropathic pain.
Source: BJ Structure - Category: Biochemistry Authors: Tags: BJ Biomolecules Source Type: research