IFNG and pulmonary fibrosis: As a result the list of leukocytes (neutrophils, lymphocytes, macrophages, eosinophils) and secreted cytokines and growth factors (TGF-β, PDGF, TNF-α, IFN-γ, IL-17, IL-1, IL-13...) involved in the progression of pulmonary fibrosis is extensive [5].