To study the role of HDAC4 in asthma, the si-HDAC4-1 and si-HDAC4-2 was transduced in human bronchial epithelial cells BEAS-2B and HBE135-E6E7 (HBE) and the silencing efficiency of HDAC4 was examined by RT-qPCR and Western blot assay; since sh-HDAC4-2 showed the best silencing efficiency (Fig. 1a, b), it was packaged into lentivirus for subsequent experimentation. The gene discussed is HDAC4; the disease is asthma.