Molecular basis for vaccine development against the ehrlichial pathogen Anaplasma marginale

Anaplasma marginale is a tick-transmitted ehrlichial pathogen causing sever e morbidity and mortality in livestock on six continents. Development of sa fe effective vaccines would be greatly facilitated by identification of the protective immune mechanisms and by understanding how the pathogen evades immune effecters to establish persistent infection. In this article, Guy Pa lmer and colleagues review recent progress in identifying how defined epito pes induce protective immunity and the role of antigenic variation in these epitopes as a mechanism of persistence.