Phagocytosis of DVs leads to impairment of PMNs-function. (A) ROS generation was detected using the luminol-based chemiluminescence assay. Control PMNs incubated for 60 minutes in medium and subsequently challenged with S aureus mounted a vigorous response. Incubation of cells with DVs induced an initial bell-shaped response, but ROS generation upon subsequent bacterial challenge was conspicuously blunted. (B) Microscopic examination undertaken 20 minutes after S aureus challenge revealed effective phagocytic uptake of the bacteria in both cases (left: control PMNs; right: PMNs preloaded with DVs). Scale bar indicates 10 μm. (C) Assessment of bacterial killing revealed marked impairment of bactericidal activity in DV-laden cells. One representative experiment of 4 independent experiments is shown. Results are expressed as means of triplicates ± SD; *P < .001 compared with control.