In the present study, using immunofluorescence, we confirmed the strong upregulation of α-SMA expression in the BLM group, whereas the expression levels of α-SMA in lung tissue decreased significantly in the BLM + HYAP group, suggesting that the proliferation and differentiation of fibroblasts were significantly inhibited by treatment with HYAP via ISI. The gene discussed is ACTA1; the disease is Bloom syndrome.