S100A9 and cystic fibrosis: EHF is intimately involved in regulating the wound response, inflammation and tissue remodelling, all of which are integral components of CF lung pathology.11, 12 For example, EHF enhances expression of S100 Calcium Binding Proteins A8 and A9 (S100A8 and S100A9), which are essential for cell motility52, 53, 54 and thus the wound response.