In the bleomycin-induced mice model of pulmonary fibrosis, myeloid PTEN-deficient mice exhibited the enhanced TGF-β1 activation and collagen deposition, decreased number of macrophages and T cells, and aberrant macrophage polarization with augmentation of various proinflammatory cytokines such as IL-6 and TNF-α. This evidence concerns the gene PTEN and pulmonary fibrosis.