Optimal conditions for the toxoiding of pertussis toxin with 1-ethyl-3(3-dimethylaminopropyl) carbodiimide · HCl

Abstract

The optimal conditions for toxoiding a pertussis toxin (PT) preparation with 1‐ethyl‐3(3‐dimethylaminopropyl) carbodiimide · HCl (EDAC) were determined. The prime factor affecting the toxoiding of PT was the EDAC to protein ratio. A ratio of 40–80 : 1 EDAC to protein by weight was optimal for abolishing the acute toxicity, histamine‐sensitising and leucocytosis‐promoting activities associated with PT, whilst maintaining the antigenicity of the vaccine antigens. An EDAC‐toxoid also manifested no late histamine‐sensitising activity. Duration of exposure to EDAC, temperature and pH value of the reaction were found not be be critical for toxoiding. The data indicated that the use of EDAC for toxoiding PT in a B. pertussis extract is a simple and reproducible procedure and should be considered as a method for the production of acellular pertussis vaccines.

Conjugation of capsular polysaccharide to α-haemolysin from Staphylococcus aureus as a glycoprotein antigen

“…Glutaraldehyde was supposed to be such a toxoiding reagent. More recently, carbodiimide was shown to be also effective, but a high carbodiimide-protein ratio was required to abolish pertussis toxin toxicity [14].…”