MMP9 and Granuloma: Consistent with these findings by using various MMP inhibitors, MMP‐9‐deficient mice also showed a reduction in macrophage recruitment to the lungs and developed comparatively smaller granulomas.21 Similarly, Volkman and colleagues discovered the molecular mechanisms that Mtb uses to induce granuloma formation.118 They showed that the 6‐kDa early secreted antigenic target (ESAT‐6) induces MMP‐9 in epithelial cells adjacent to infected macrophages.