Yersinia outer proteins (Yops) E, K and N are antigenic but non-protective compared to V antigen, in a murine model of bubonic plague

摘要

A model was used to test immunogenicity in Yersinia outer proteins (Yops). Immunogenicity of V antigen was compared with E, K and N in immunized mice. Solid protection was achieved by 2 doses of V as had been shown in previous experiments. It was demonstrated that Yops E, K and N were antigenic, but non-protective against relatively low challenge doses of Yersinia pestis infection. Although YopE, GST-YopK and YopN elicited strong humoral responses, it is clear from the challenge experiments, that unlike V antigen, these proteins are unable to induce sufficient protective immune responses in a murine model of bubonic plague to promote survival of the host. Compared with V antigen, Yops E, K and N may only be of limited use in a subunit vaccine forplague.