The effect of human eosinophils on cultured human nasal epithelial cell activity and the influence of nedocromil sodium in vitro.

Although there is increasing evidence of a pathogenic role for eosinophils in the airway epithelium, there is little direct evidence which demonstrates that eosinophils influence epithelial cell activity in humans. We have cultured human nasal epithelial cells in vitro and studied the effect of isolated human eosinophils on the ciliary beat frequency (CBF) and cell membrane integrity of these cells after incubation in the absence or presence of 0.1 microM phorbol 12-myristate 13-acetate (PMA) or 0.1 mg/ml opsonized latex beads and the absence or presence of 10(-5) M nedocromil sodium. CBF was monitored by an analogue contrast-enhancement technique, and cell damage was assessed by release of 51Cr from the cells. Cell cultures were also assessed for the percentage of eosinophil cationic protein (ECP) released into the medium at the end of incubation. Neither 0.1 microM PMA, 0.1 mg/ml opsonized latex beads, 10(-5) M nedocromil sodium, nor eosinophils alone altered the CBF of the epithelial cells. PMA-stimulated eosinophils, however, attenuated the CBF significantly, from 10.2 +/- 0.3 to 8.8 +/- 0.4 Hz (P less than 0.05) after 15 h of incubation. Similarly, opsonized latex bead-stimulated eosinophils led to a significant attenuation of CBF from 9.2 +/- 0.3 to 8.4 +/- 0.3 Hz (P less than 0.05), 6.9 +/- 0.5 Hz (P less than 0.001), and 7.5 +/- 0.3 Hz (P less than 0.001) after 2, 15, and 24 h of incubation, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)