Gene Therapy Based on Fragment C of Tetanus Toxin in ALS: A Promising Neuroprotective Strategy for the Bench to the Bedside Approach

In particular, ALS belongs to the group of motor neuron diseases, involving the loss of cortex, brainstem, and spinal cord motor neurons that result in muscle paralysis [1]. Motor neurons, which are localized in the brain, brainstem and spinal cord, behave as a crucial links between the nervous system and the voluntary muscles of the body, as they let synaptic signals travel from upper motor neurons in the brain to lower motor neurons in the spinal cord and finally to muscles. In accordance with the revised El Escorial criteria [2], both the upper motor neu‐ rons and the lower motor neurons degenerate or die in ALS, and as a consequence the com‐ munication between neuron and muscle is lost, prompting the progressive muscle weakening and the appearance of fasciculations. In the later stages of the disease, patients become para‐ lyzed although the disease usually does not impair a person's mind or intelligence.