Formyl-methionyl-leucyl-phenylalanine (FMLP) does not impair ciliary beat frequency in chronic airflow limitation (CAL)

The pathogenesis of CAL is poorly understood. Bacterial products are present in the bronchial tree of many patients and susceptibility to these products may contribute to a vicious cycle by which recurrent infection slows mucociliary clearance (MCC), accelerates lung damage and predisposes to further infection. The bacterial oligopeptide FMLP causes bronchoconstriction in some non-asthmatic patients with CAL. It has been suggested that FMLP may thus contribute to the progression of CAL but its effects on MCC are not known. Aim: To investigate the effect of FMLP on ciliary beat frequency (CBF) in CAL. (CBF is a determinant of MCC and nasal CBF is related to tracheobronchial CBF). Methods: Three groups (n=7) were studied - non-smokers (NSC) and smokers (SC) with normal lung function and patients with CAL secondary to smoking. All subjects had lung function tests. Ciliated epithelium (CE) was obtained from each subject by nasal mucosal brushing and incubated in serial dilutions of FMLP (104M, 10SM, 106M) for 30 min. CBF was measured every 6 min. Control samples of CE were incubated in serial dilutions of the diluent alone. Results were calculated as % change in CBF for FMLP-CE with respect to Diluent-CE. Results for each group were compared by analysis of variance. Results: The GAL group did not differ significantly (p<0.05) from the NSC and SC groups at any time. Conclusion: FMLP does not impair CBF, measured in vitro, in ciliated epithelium from CAL patients.