The elevation of TGFβ+% and the trend to increased Th17% in patients with chronic P. aeruginosa infection is interesting, especially as in our cohort such increases are not associated with other infections including S. aureus and A. fumigatus. This suggests that the increases may be related to the persistent and highly inflammatory nature of the response to P. aeruginosa, and it is possible that these markers could be useful to monitor/predict infection, as previously suggested by Tiringer et al [14]. Here, TGFB1 is linked to infection.