Functional analysis of the intracellular survival of <i>Mycobacterium avium</i> subsp. <i>paratuberculosis</i> in THP-1 cells using CRISPR interference

Johne's disease, caused by <i>Mycobacterium avium</i> subsp. <i>paratuberculosis</i> (MAP) is a worldwide issue in the dairy industry and has a possible connection to Crohn's disease (CD) in humans. Despite its potential contribution to the etiology of CD, there have been few studies focusing on the virulence of MAP against human macrophages. In the current study, we investigated MAP virulence along with intracellular survival in human THP-1 macrophages using functional analysis of MAP CRISPR interference (CRISPRi) mutants at the knockdown of genes associated with mycobacterial virulence. The identified potential genes represent novel candidate classes that could be necessary for MAP virulence by exploring intracellular survival during host infection and could provide novel insights for future studies on the utilization of CRISPRi.