In order to investigate the pathogenic roles of oxidative stress and inflammation in the development of PF, the expression of key components of signaling cascades of oxidative stress and inflammation, including antioxidative factors such as Nrf2, Ho-1, and Nox family numbers and the key molecules of TLR/MyD88 signaling cascade, were examined in the lungs of BLM-induced PF mice by immunoblotting and immunofluorescence (IF) assays (Figure 1). This evidence concerns the gene HMOX1 and pemphigus foliaceus.