As immunohistochemical staining demonstrated, MMP2 and MMP9 expression in atherosclerotic lesions was substantially decreased in mice treated with Ad‐Nkx2‐5, compared to Ad‐EV‐treated controls, and Ad‐shNkx2‐5 infection significant increased the levels of MMP2 and MMP9 (Figure 4A and 4B). The gene discussed is MMP9; the disease is infection.