Interneuronal Transfer and Distal Action of Tetanus Toxin and Botulinum Neurotoxins A and D in Central Neurons

Cell Rep. 2016 Aug 16;16(7):1974-87. doi: 10.1016/j.celrep.2016.06.104. Epub 2016 Aug 4.


Recent reports suggest that botulinum neurotoxin (BoNT) A, which is widely used clinically to inhibit neurotransmission, can spread within networks of neurons to have distal effects, but this remains controversial. Moreover, it is not known whether other members of this toxin family are transferred between neurons. Here, we investigate the potential distal effects of BoNT/A, BoNT/D, and tetanus toxin (TeNT), using central neurons grown in microfluidic devices. Toxins acted upon the neurons that mediated initial entry, but all three toxins were also taken up, via an alternative pathway, into non-acidified organelles that mediated retrograde transport to the somato-dendritic compartment. Toxins were then released into the media, where they entered and exerted their effects upon upstream neurons. These findings directly demonstrate that these agents undergo transcytosis and interneuronal transfer in an active form, resulting in long-distance effects.

MeSH terms

  • Animals
  • Botulinum Toxins / metabolism*
  • Botulinum Toxins / toxicity
  • Botulinum Toxins, Type A / metabolism*
  • Botulinum Toxins, Type A / toxicity
  • Cell Communication
  • Fluorescent Dyes / chemistry
  • Hippocampus / cytology
  • Hippocampus / drug effects
  • Hippocampus / metabolism*
  • Lab-On-A-Chip Devices
  • Mice
  • Neurons / cytology
  • Neurons / drug effects
  • Neurons / metabolism*
  • Primary Cell Culture
  • Protein Transport
  • Rats
  • Tetanus Toxin / metabolism*
  • Tetanus Toxin / toxicity


  • Fluorescent Dyes
  • Tetanus Toxin
  • botulinum toxin type D
  • Botulinum Toxins
  • Botulinum Toxins, Type A