IRF3 and infection: When weakly virulent Mycobacterium tuberculosis infects macrophages, it can activate IRF3 and IRF7, resulting in increased IFN-I production and thus controlling the infection, while strongly virulent M. tuberculosis inhibits IRF7 expression and produces cytokine storm due to its ability to activate Oasl1, a negative regulator of IFN-I, which ultimately leads to cell death of macrophage, indicating the inhibitory role of IRF7 in M. tuberculosis infection (39).