Cystic fibrosis serum does not inhibit human ciliary beat frequency

The effect of cystic fibrosis (CF) serum on human respiratory tract ciliary beat frequency (CBF) was studied to investigate the possible relevance of CF-serum-induced disruption of rabbit tracheal ciliary motility to human disease. Nasal ciliated epithelium from patients with CF and from normal subjects was incubated at 37 degrees C in CF serum, in normal human serum (NHS), or in nutrient medium. CBF was measured photometrically at time intervals up to 3 h. The effect of CF serum on human trachea and of CF serum, NHS, and rabbit serum on rabbit tracheal CBF was also studied. Mean CBF for all the normal and CF nasal cilia incubated in CF serum, NHS, or nutrient medium was not significantly different and did not fall during 3 h. Human tracheal CBF did not fall during 3 h. The CBF for rabbit trachea in rabbit serum did not slow and rabbit trachea in NHS slowed after 150 min. Rabbit trachea in CF serum beat more slowly than all the other groups (p less than 0.001) progressing to ciliostasis between 45 and 150 min. We conclude that human respiratory tract ciliary motility, as measured by CBF in vitro, is unaffected by factors in CF serum that impair rabbit tracheal ciliary activity.