# Advances in Clostridial Neurotoxins: Passage of the Intestinal Barrier and Targeting of Specific Neuronal Cells

## TL;DR

This paper explores how clostridial neurotoxins pass through the intestinal barrier and target specific neurons, offering insights for disease prevention and therapeutic development.

## Contribution

The paper provides new structural and functional insights into BoNT and TeNT receptors, aiding in the development of prevention and treatment strategies.

## Key findings

- BoNTs associate with protective proteins that help them survive and pass through the intestinal barrier.
- TeNT enters motor neurons and is transported retrograde to target inhibitory interneurons in the central nervous system.
- Understanding toxin receptors improves knowledge of toxin trafficking and entry into neuronal cells.

## Abstract

Clostridial neurotoxins, botulinum neurotoxins (BoNTs), and tetanus neurotoxin (TeNT) are potent toxins responsible for severe diseases, botulism and tetanus, respectively. BoNTs associate with non-toxic proteins (non-toxic non-hemagglutinin, hemagglutinins, and OrfXs), which protect BoNTs against acidic pH and protease degradation and facilitate BoNT passage through the intestinal barrier. TeNT enters motor neurons and undergoes a retrograde axonal transport until the target inhibitory interneurons in the central nervous system. BoNTs and TeNT recognize specific cell surface receptors which consist of complex sets of protein(s)-glycan-gangliosides and determine specific cell entry pathways. Recent data on structural and functional investigations of BoNT and TeNT receptors bring a better understanding of toxin trafficking in the host and entry into target neuronal cells, which is useful for the development of updated strategies of prevention and treatment of the corresponding diseases. Since clostridial neurotoxins, notably BoNTs, are important therapeutic tools, detailed knowledge of their activity opens the way of the development of engineered molecules for specific clinical applications.