Assessment of immunogenicity of alginate microparticle containing Brucella melitensis 16M oligo polysaccharide tetanus toxoid conjugate in mouse

Brucellosis is an infectious disease caused by Brucella bacteria, affecting animals and humans. It is found as an endemic disease in many parts of the world, especially in the Middle East, Central Asian, and South American countries. The objective of this study was to prepare alginate microparticle containing conjugate of Brucella melitensis 16 M oligopolysaccharide (OPS) with tetanus toxoid, and to assess its immunogenicity in mouse, in order to find a new method of confronting brucellosis. In this study, we extracted OPS from lipopolysaccharide (LPS) and conjugated it with tetanus toxoid by amidation method. Then, the obtained conjugate was condensed by gel filtration, followed by emulcification method in iso–octane organic phase to prepare alginate microparticles containing the conjugate. In our study, sera titr of antibodies IgM, IgA, IgG2a, IgG1, IgG2b, IgG3, and total IgG generated against oligopolysaccharide was performed by ELISA test. The final results, considering the obtained immunogenicity and the increased titer of antibodies IgG1 (19 times), IgG3 (19 times), IgG (15 times), and IgM (9 times) after injection of produced microparticle in mouse indicates appropriateness of the produced microparticle as a candidate vaccine. Thus, it could be concluded that alginate microparticles containing conjugates of B.melitensis 16 M oligopolysaccharide with tetanus toxoid can be proposed as a candidate anti– brucellosis vaccine. Keyword: Brucella melitensis, Microparticle, Tetanus, Alginate, Vaccine.