Application of an Endothelial Cell Culture Assay for the Detection of Neutralizing Anti-Clostridium Perfringens Beta-Toxin Antibodies in a Porcine Vaccination Trial
Institute of Animal Pathology, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland
IDT Biologika GmbH, Business Unit Animal Health, Research and Development, 06861 Dessau-Rosslau, Germany
Veterinary Public Health Institute, Vetsuisse Faculty, University of Bern, 3012 Bern, Switzerland
Author to whom correspondence should be addressed.
Toxins 2019, 11(4), 225; https://doi.org/10.3390/toxins11040225
Received: 4 March 2019 / Revised: 8 April 2019 / Accepted: 9 April 2019 / Published: 15 April 2019
(This article belongs to the Collection Clostridium difficile/Clostridium sordellii and Clostridium perfringens Toxins)
Background: Beta-toxin (CPB) is the major virulence factor of Clostridium perfringens type C, causing hemorrhagic enteritis in newborn pigs but also other animals and humans. Vaccines containing inactivated CPB are known to induce protective antibody titers in sow colostrum and neutralization of the CPB activity is thought to be essential for protective immunity in newborn piglets. However, no method is available to quantify the neutralizing effect of vaccine-induced antibody titers in pigs. (2) Methods: We developed a novel assay for the quantification of neutralizing anti-CPB antibodies. Sera and colostrum of sows immunized with a commercial C. perfringens type A and C vaccine was used to determine neutralizing effects on CPB induced cytotoxicity in endothelial cells. Antibody titers of sows and their piglets were determined and compared to results obtained by an ELISA. (3) Results: Vaccinated sows developed neutralizing antibodies against CPB in serum and colostrum. Multiparous sows developed higher serum and colostrum antibody titers after booster vaccinations than uniparous sows. The antibody titers of sows and those of their piglets correlated highly. Piglets from vaccinated sows were protected against intraperitoneal challenge with C. perfringens type C supernatant. (4) Conclusions: The test based on primary porcine endothelial cells quantifies neutralizing antibody activity in serum and colostrum of vaccinated sows and could be used to reduce and refine animal experimentation during vaccine development.