Fig. 1: SARS-CoV-2 and cystic fibrosis.

The spike protein on the virion binds to the ACE2 cell membrane protein. Cellular entry is facilitated by the TMPRSS2 and furin enzymes, one or more of which may be altered in CF. Once inside the cell, viral processing, may be influenced either by overactive inflammation and/or CF-affected cellular processes including autophagy, mitophagy, endosomal function and cellular metabolism, which may all be co-opted by COVID-19 for viral replication.