TGFB1 and idiopathic pulmonary fibrosis: Another study illustrated that CO-bound hemoglobin vesicles (CO-HbV), a type of nanotechnology-based CO donor, could mitigate IPF by suppressing NOX4 activity to reduce reactive oxygen species (ROS) and decreasing transforming growth factor-β (TGF-β) and inflammatory cytokines including TNF-α, IL-1β, and IL-6 in the lung [46] (Figure 2).