Overview of Johne's disease immunology

Johne's disease or paratuberculosis is one of the most economically important diseases of the livestock. Most of the economic losses associated with paratuberculosis are related to decreased milk production, reduced fertility and higher rates of culling. Understanding the immunology of the disease is very important for better understanding of the interplay between the host and the causative agent, Mycobacterium avium subsp. paratuberculosis (MAP). After uptake of MAP by macrophages residing in host's intestinal tissue, two possible scenarios may emerge; MAP may be destroyed or may establish persistent infection within the macrophages. If MAP persists in the infected macrophage, it continuously modulates adaptive immune responses of the animal. In this short review we describe the host-pathogen interactions in Johne's disease and highlights potential protective mechanisms in order for future design of more effective diagnostic method and vaccine.