Vaccine and Infectious Disease Organization -
International Vaccine Centre

Johne’s disease in cattle – pathogenesis and control of Mycobacterium avium subspecies paratuberculosis

Project Team: Scott Napper, Philip Griebel, Andrew Potter, T. Facciuolo

Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent of Johne’s Disease and may be linked to Crohn’s Disease in humans. Although infected animals can clear the organism, MAP has the ability to subvert the immune system by hiding in ileal macrophage. This results in persistently infected animals that shed the organism into the environment.

Research is aimed at improving the understanding of MAP pathogenesis. Genomic and proteomic functional studies will examine the interaction between MAP and ileal Peyer’s Patch macrophages in isolated cells and whole animals. Kinome analysis will analyze macrophage signaling pathways.

These studies will form a basis for studying the effect of immunomodulatory compounds on macrophages which are designed to determine if the activation of specific pathways can overcome the suppressive effect of MAP. This will offer new targets for therapeutics and vaccines. A reverse vaccinology approach will be used to develop vaccine candidates for Johne’s disease and bovine tuberculosis.