Ditina, M.A., Meringova, L.F., Leontyeva, G.F., Grabovskaya, K.B., Yang, A., Shen, Z., Suvorov, A.N.

Comparative study of experimental conjugated and combined vaccines against group B streptococci

Research Institute of Experimental Medicine, Saint-Petersburg, Russia; Beijing Children’s Hospital, China

Immunogenic properties of recombinant protein ScaAB mixed with polypeptide P6 as well as conjugate of the former with capsular polysaccharide type III (PSIII) were assessed. Protein-polysaccharide conjugate was synthesized by reductive amination method. Immunogenicity was studied on the mouse model using aluminium hydroxide as adjuvant. Antibody titers in antisera were measured by immunoenzyme assay. Functional activity of antibodies was evaluated by opsonophagocytic test. Immunization with ScaAB-PSIII conjugate resulted in increased immune response to both ScaAB and polysaccharide. Administration of ScaAB and P6 proteins mixture compared to their separated administration led to increased of antibody titer and prolonged circulation of specific antibodies. Injection of studied vaccines increased opsonizing activity of antisera compared to immunization with uncombined components.
Zh. Mikrobiol. (Moscow), 2009, No. 1, P. 37—41