Vaccines Using Clostridium perfringens Sporulation Proteins Reduce Necrotic Enteritis in Chickens

Clostridium perfringens is the prevalent enteric pathogen in humans and animals including chickens, and it remains largely elusive on the mechanism of C. perfringens-induced enteritis because of limited animal models available. In this study, we investigated the role of C. perfringens sporulation proteins as vaccine candidates in chickens to reduce necrotic enteritis (NE). C. perfringens soluble proteins of vegetative cells (CP-super1 and CP-super2) and spores (CP-spor-super1 and CP-spor-super2) were prepared, and cell and chicken experiments were conducted. We found that deoxycholic acid reduced C. perfringens invasion and sporulation using the Eimeria maxima and C. perfringens co-infection necrotic enteritis (NE) model. C. perfringens enterotoxin (CPE) was detected in the CP-spor-super1&2. CP-spor-super1 or 2 induced cell death in mouse epithelial CMT-93 and macrophage Raw 264.7 cells. CP-spor-super1 or 2 also induced inflammatory gene expression and necrosis in the Raw cells. Birds immunized with CP-spor-super1 or 2 were resistant to C. perfringens-induced severe clinical NE on histopathology and body weight gain loss. CP-spor-super1 vaccine reduced NE-induced proinflammatory Ifnγ gene expression as well as C. perfringens luminal colonization and tissue invasion in the small intestine. Together, this study showed that CP-spor-super vaccines reduced NE histopathology and productivity loss.