ABSTRACT
The breadth and applicability of nanoparticles as vaccine delivery tools offer unique opportunities to researchers in developing safe and effective vaccines against intracellular pathogens. Surviving within difficult environments presents a major challenge, but in return, an intracellular lifestyle provides a pathogen with refuge from many antibiotics and components of the host immune system. C. burnetii is unique among intracellular bacterial pathogens as its replicative niche has properties of a phagolysosome, a typically microbicidal compartment. Pathogens are initially recognized by the innate immune system through pattern-recognition receptors on the surface of host immune cells, which recognize unique pathogen-associated molecular patterns. When an individual is exposed to a pathogen, an immune response consisting of humoral and cellular constituents is activated. The role of antibody in vaccine-induced protection has been documented in multiple studies over the years starting with work by Abinanti and Marmion, which demonstrated that a mixture of antibodies and C. burnetii was not infectious in susceptible animals.
