S100A8 and cystic fibrosis: In contrast, similar studies of 20 day-old Bc-CF lungs, which do not progress to the inflammatory lung disease phenotype, maintained under identical conditions showed no significant increase in S100A8 expression (p ≤ 0.5), although expression of S100A9 was significantly elevated (p ≤ 0.001) in a manner similar to that of the B6-CF samples (Fig. 1B).