Humoral response in mice immunized with outer membrane proteins of Shigella flexneri

Intraperitoneal immunization of mice with outer membrane proteins (OMP) of Sh. flexneri induced in the animals a synthesis of specific antibodies. Their level determined by ELISA test was found to be relatively low in the sera of animals immunized with a single dose (10 micrograms) of OMP; it was markedly higher in mice immunized with two doses of OMP, and very high after three fold immunization. The specific antibodies maintained in the animals for 8-16 weeks after immunization. Anti-OMP sera given to normal mice by intraperitoneal route protected them not only against challenge with homologous Shigella but also against Proteus and Escherichia.