MMP9 and COVID-19: The IHC analysis showed increased expression for caspase-1 (p=0.0010), ICAM (p<0.0001), CD163 (p=0.0021), IL-1β (p<0.0001), IL-4 (p<0.0001), IL-6 (p<0.0001), MMP-9 (p=0.0002), TNF-α (p<0.0001), TGF-β (p=0.0063), type 1 collagen (p<0.0001) and type 3 collagen (p<0.0001) in the COVID-19 patients compared to the control.