As another explanation, CF isolates have significant, but broadly differing, sensitivity to AMPs such as cathelicidins29,30, which may relate to well-described changes in surface structures such as LPS or to possession of temporate phage; Pf1 was shown in isolates of Liverpool Epidemic Strain to protect against killing by LL-37 by forming inactivating aggregates30. This evidence concerns the gene ADSL and cystic fibrosis.