an assessment of antigen immobilization methods onto the mesoporous silica nanoparticles on the vaccine efficacy against necrotic enteritis

Aim and background: necrotic enteritis (ne) is caused by some pathogenic strains of clostridium perfringens (c.p). due to the multifactorial nature of this disease and the unknown exact mechanism of pathogenesis, no effective commercial vaccine has been developed yet. based on many types of research, nanoparticles significantly improve the efficiency of vaccines due to their ability to control the release of antigen, antigen protection and its targeted delivery. thus, in this project, for the first time, mesoporous silica nanoparticles (msnps) were considered as an adjuvant and delivery vehicle for vaccine development against ne. the chimeric antigen, consisting of two main toxins, alpha and netb, was immobilized onto the msnps using covalent conjugation or physical adsorption methods. and the efficiency of two formulations was compared in protective immunity induction in chicken.methods: 1.protein expression and ni-nta purification, 2.msnps synthesis via template removal and functionalization by edc or succinate anhydride, 3.immobilization of fusion protein using covalent conjugation or physical adsorption methods, 4.chicken immunization and challenge test.results and discussion: both msnp-based formulations induced humoral immunity significantly; but the best one was conjugated vaccine and the least intestinal lesions was observed in chickens immunized with conjugated vaccine orally. it is probably due to the greater stability of the protein onto the nanoparticle surface in the harsh environment of the digestive tract.conclusion: antigen conjugated onto the nanoparticle surface significantly reduced intestinal lesions, and development of nanoparticle-based vaccines is a promising platform for control of ne.