MMP2 and idiopathic interstitial pneumonia: The HSV-1 infected primary cultures from IPF patients showed lower expression levels of MMP2 compared to the infected primary cultures from healthy donors with ratio of the means 0.01 (p = 0.132) (Table 3), as well as for CCL19 with ratio of the means 0.0001 (p = 0.246) and CCL21 with ratio of the means 10−8 (p = 0.001).