IL1R2 and cystic fibrosis: There was no difference in sIL-1R2 protein production between non-CF or CF AEC, however, sIL-1R2 was significantly induced after infection in CF AEC when compared to non-CF AEC (16.5 ± 2.1 pg/mL vs. 49.8 ± 38.1 pg/mL; p < 0.05) (Figure 4B).