Fig. 8. NETs inhibits surface-active properties of pulmonary surfactant, and SP-D mitigates the inhibitory effect of NETs on surfactant.

Surface activity is assessed by the isotherms obtained from the CBS, thermostated at 37 °C. Representative isotherms from each group of samples are shown. Surfactant films were formed upon injection of a suspension of surfactant (20 mg/mL) with or without NETs, in the absence or presence of SP-D (0.67% w/w with respect to phospholipid). The upper set of isotherms show IA to the air-water interface of a bubble over a 5-min period. The lower set of isotherms illustrates dynamic compression-expansion cycling (at 20 cycles/min) for cycles 1, 10 and 20. The detail parameters are enlisted in Supplementary Table 1.