Because of the MOMC’s homing ability, MOMC/PER reached directly to the lungs, the DiR fluorescence intensity in the lungs was respectively 3.5- and 0.5-fold greater than that in the liver in the MOMC/PER-DiR and MOMC-DiR groups, as shown in Fig. 5E. Additionally, the MOMC/PER can release the PER NPs retargeting the injured AEC II after responding to the matrix metalloproteinase-2 (MMP-2) in IPF tissues. Here, MMP2 is linked to idiopathic pulmonary fibrosis.