In infection-triggered exacerbations, bacterial proapoptotic peptides (e.g., corisin) promote mitochondrial ROS accumulation and membrane destabilization in AECs, suppressing the levels of the antiapoptotic factors baculoviral IAP repeat-containing (BIRC) 5, BIRC7, and B-cell lymphoma 2 (BCL2), while upregulating those of caspase-3/Apaf-1 (D'Alessandro-Gabazza et al., 2020). Here, CASP3 is linked to infection.