TGFB1 and pemphigus foliaceus: Chang et al. (2017) reported extensive lung fibrotic injury in histological investigation and enhanced content of hydroxyproline, collagen types I and III in rat lung tissue exposed to nano-nickel oxide (NiO, 0.015, 0.06, and 0.24 mg/kg; 6 weeks). This study suggested that PF induction by NiO-NPs may be related to TGF-β1 activation. Carbon black nanoparticles (5 mg/m3 and 30 mg/m3; 14, 28, and 90 days) also induced PF in rats, which might be linked with persistent lung inflammation through NLRP3 inflammasome activation (Zhou et al., 2020).