IL17A and cystic fibrosis: In our study here, the cells isolated from the lungs of the BCG-L91 group showed significantly greater expansion in the percentage of multifunctional Th1 cells (IFN-γ+TNF-α+) (L91: p ≤ 0.005, ST-CF: p ≤ 0.005) and Th17 cells (IL-17+IFN-γ+) (L91: p ≤ 0.005, ST-CF: p ≤ 0.05) following in vitro stimulation with either L91 or ST-CF, compared to the BCG group (Fig. 2c–f).