Background and Purpose:
Tetanus neurotoxin has many potential therapeutic applications, due to
its ability to increase localised muscle tone when injected directly
into a muscle. It is a closely related molecule to botulinum neurotoxin
(most commonly known as Botox), which has been widely used to release
muscle tension for therapeutic and cosmetic applications. However,
tetanus toxin has been relegated to the “maybe pile” for protein
therapeutics — as most of the population is vaccinated, leading to
highly effective antibody-mediated protection against the toxin. The
potential for tetanus-based therapeutics remains substantial if the
problem of pre-existing immunity can be resolved.
Experimental Approach: A well-established murine model of
localised muscular contraction was utilised. We administered functional
tetanus toxin combined with an immunogenic, but functionally inactive,
decoy molecule.
Key Results: Incorporation of the decoy molecule greatly
reduces the dose of active toxin required to induce a localised increase
in muscle tone in mice vaccinated with the human toxoid vaccine.