Potency against enterotoxemia of a recombinant Clostridium perfringens type D epsilon toxoid in ruminants

Abstract

Enterotoxemia, a disease that affects domestic ruminants, is caused mainly by the epsilon toxin from Clostridium perfringens type D. Its eradication is virtually impossible, control and prophylaxis are based on systematic vaccination of herds with epsilon toxoids that are efficient in inducing protective antibody production. The use of recombinant toxins is one of the most promising of these strategies. This work evaluates the potency of a Cl. perfringens type D epsilon toxoid expressed by Escherichia coli administered to goats, sheep, and cattle. The etx gene was cloned into the pET-11a plasmid of E. coli strain BL21 to produce the recombinant toxin. Rabbits (n=8), goats, sheep, and cattle (n=5 for each species) were immunized with 0.2mg of the insoluble recombinant protein fraction to evaluate vaccine potency of the epsilon toxoid studied. Antibody titers were 40, 14.3, 26, and 13.1 IU/mL in the rabbit, goat, sheep, and cattle serum pools, respectively. The epsilon toxoid produced and tested in this work is adequate for immunization of ruminants against enterotoxemia.

Recombinant Alpha, Beta, and Epsilon Toxins of Clostridium perfringens: Production Strategies and Applications as Veterinary Vaccines

“…For example, they are associated with a risk of residual toxicity due to incomplete formaldehyde inactivation and a risk of residual formaldehyde being present [18,19,20]. Furthermore, the potency of the vaccine varies from batch to batch [17,21,22]. In addition, the toxoids that are produced from the supernatant of C. perfringens cultures are not pure (i.e., other toxins and proteins are present), and this accounts for a higher degree of antigen diversity in the vaccine [23].…”

Clostridium perfringens epsilon toxin mutant Y30A-Y196A as a recombinant vaccine candidate against enterotoxemia

“…These vaccines are based on either formaldehyde treated C. perfringens type D culture filtrate or formaldehyde-inactivated recombinant wild type toxin [11,12]. These vaccine preparations have several disadvantages: (1) complete removal of free formaldehyde is required to avoid possible toxic side effects, (2) toxoiding using formaldehyde can show considerable batch to batch variation in immunogenicity of these vaccines [12], (3) inflammatory responses following vaccination can lead to reduced feed consumption [13] and (4) reversion to toxicity may occur in incompletely inactivated bacterial toxins. Therefore, there is a need to identify Etx variants with reduced toxicity relative to wild type toxin.…”

Isolation, Specification, Molecular Biology Assessment and Vaccine Development of Clostridium in Iran: A Review

“…Recently, Clostridium perfringens type D epsilon toxin gene was cloned and expressed in E. coli and its immunization response was tested in vivo. Results showed good protection against native epsilon toxin (22,23).…”