In osteomyelitis, infections can increase the activity of MMP9 and the release of various pro-inflammatory factors such as IL1β, which in turn worsens the degree of inflammation and promotes the progression of osteomyelitis.[39] Studies have shown that MMP9 is highly expressed in neutrophils of DFU, particularly in intravascular and peripheral tissues at the skin lesions of DFU. This evidence concerns the gene MMP9 and infection.