CCL2 and pulmonary fibrosis: Fibrosis-related genes include Col1a1, Acta2, Fn1, and Tgfb1 gene, and senescence-related genes composed of Cdkn2a, Tnf, Serpine1, Ccl2, Mmp10, and Mmp12 gene, all of which reflected the intensity of lung fibrosis and senescence events in lung tissue and pulmonary fibroblasts.