Effect of Human Macrophage Conditioned Media on TGF-β-Induced Differentiation of Lung Fibroblasts

We studied the ability of human macrophage conditioned media to inhibit differentiation of lung fibroblasts in vitro. The results showed that the conditioned medium of M-CSF-differentiated non-polarized macrophages (induced by macrophage CSF) suppressed TGF-β-induced differentiation, reduced the expression of myofibroblast markers (α-smooth muscle actin and vimentin), and decreased the contractile activity of lung myofibroblasts, while the conditioned media of dexamethasone-polarized macrophages and GM-CSF-differentiated non-polarized macrophages (differentiation stimulus is granulocyte-macrophage CSF) produced no such effects. Thus, the obtained data indicate the antifibrogenic potential of non-polarized M-CSF-differentiated macrophages.