Fig. 3

Mean fluorescence intensity (MFI) of reactive oxygen species (ROS) produced by PMNs isolated from controls (n = 16) and periodontitis subjects (n = 19). a Non-stimulated ROS production was calculated and expressed as mean ± SD. b Stimulated ROS production produced by cPMNs when incubated with phorbol myristate acetate (+PMA) or F. nucleatum (+F.nuc). c Stimulated ROS production produced by oPMNs when incubated with phorbol myristate acetate (+PMA) or F. nucleatum (+F.nuc). Ratios were labeled as fold increase and were calculated for the stimulated ROS samples (MFI of the PMA-stimulated or F.n.-stimulated samples, divided by the MFI of the non-stimulated ROS samples). ^#Comparisons oPMN versus cPMN within subjects, Paired T-test, ^#P < 0.001. ^γComparisons to corresponding non-stimulated samples (panel a), Student’s T-test, all ^γP < 0.05