In line with these findings, a significantly lower concentration of inflammatory cytokines that play an important pathogenic role in the development and progression of CS-induced airway inflammation (TNF-α, IL-1β, IL-12, and IFN-γ) was observed in serum samples of Exo-d-MAPPS-treated CS-exposed mice compared to CS+vehicle-treated animals (Figure 1(f); P < 0.05 for TNF-α, IL-12, and IFN-γ; P < 0.01 for IL-1β). Here, TNF is linked to inflammation.