Vaccination with recombinant NetB toxin partially protects broiler chickens from necrotic enteritis.

NetB toxin from Clostridium perfringens is a major virulence factor in necrotic enteritis in poultry. In this study the efficacy of NetB as a vaccine antigen to protect chickens from necrotic enteritis was examined. Broiler chickens were immunized subcutaneously with purified recombinant NetB (rNetB), formalin treated bacterin and cell free toxoid with or without rNetB supplementation.

Porcine interleukin-3 enhances DNA vaccination against classical swine fever.

DNA vectors can be used to deliver vaccine antigens that stimulate effective protective immunity in mice, but in larger, outbred animal species, the protective efficacy is lower or large doses of DNA are required. These data demonstrate that porcine interleukin-3 (IL-3) when delivered to pigs by DNA vector or in low doses as recombinant protein, can enhance antibody responses to classical swine fever virus antigen expressed from co-delivered DNA, and improve the protective efficacy of the DNA vaccine. The effect was further enhanced when IL-3 was expressed as a fusion protein with the potyvirus coat protein.