Genetic detoxification of bacterial toxins: A new approach to vaccine development

R Rappuoli, G Douce, G Dougan, and M Pizza 

 For preventing a variety of different bacterial infectious diseases, toxoids or chemically  detoxified bacterial toxins, have been successfully used as vaccines. Superior to the classical  toxoids both in safety and in immunogenicity, genetically inactivated toxins should replace the  classical toxoids in vaccines. For the innovative approaches to vaccination, genetically  inactivated toxins represent a novel class of immunogens with unique properties.  

https://pubmed.ncbi.nlm.nih.gov/7580303/