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Macrophage Epithelial Reprogramming Underlies Mycobacterial Granuloma Formation and Promotes Infection

ABSTRACT: Mycobacterium tuberculosis infection in humans triggers formation of granulomas, tightly organized immune cell aggregates that are the central structure of tuberculosis. Infected and uninfected macrophages interdigitate, assuming an altered, flattened appearance. Although pathologists have described these changes for over a century, the molecular and cellular programs underlying this transition are unclear. We find that mycobacterial granuloma formation is accompanied by macrophage induction of canonical epithelial molecules and structures. Using the zebrafish-Mycobacterium marinum model, we identify fundamental macrophage reprogramming events that parallel E-cadherin-dependent mesenchymal-epithelial transitions. Macrophage-specific disruption of E-cadherin function results in disordered granuloma formation, enhanced immune cell access, decreased bacterial burden and increased host survival, suggesting that the granuloma can also serve a bacteria-protective role. In humans, we find that granuloma macrophages are similarly transformed. Long considered largely through the prism of immune signaling pathways, granuloma macrophages are reprogrammed by epithelial modules that alter the trajectory of mycobacterial infection.

ORGANISM(S): Danio rerio

PROVIDER: GSE81913 | GEO | 2016/10/18

REPOSITORIES: GEO

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Macrophage Epithelial Reprogramming Underlies Mycobacterial Granuloma Formation and Promotes Infection

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