Role of Matrix Metalloproteinases and Their Inhibitor in the Development of Early Pulmonary Fibrosis in Mice Infected with Influenza A/H5N1 A/GOOSE/Krasnoozerskoye/627/05 Virus

High levels of macrophages and fi broblasts expressing MMP-2, MMP-9, and MMP-10 against the background of progressing early fi brosis of the lungs (manifesting in an increase in volume density of type I, III, IV, and VI collagens) were found in C57Bl/6 mice infected with infl uenza A/H5N1 A/goose/Krasnoozerskoye/627/05 virus. Progressing fi brosis of the lungs in infected mice was associated with imbalance of collagen synthesis and degradation processes conjugated with high levels of macrophages and fi broblasts expressing TIMP-2.