Figure 1.

Periodontal pathogen outer membrane vesicles (OMVs) bind THP-1 cell subsets. Cell binding assays were performed with THP-1 cell suspensions of monocytes and monolayers of M(naïve) and M(IFNγ) macrophages incubated with PKH26-labeled Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia OMVs at three OMV to cell ratios (10:1, 50:1, and 100:1). Cells were incubated for 60 min, washed, and OMV binding determined by flow cytometry. Results are expressed as the percentage of THP-1 cells with at least one bound OMV (A,C,E) or the mean fluorescence intensity (MFI) of each sample (B,D,F), which indicates the quantity of OMVs bound per cell. Data are represented as mean ± SEM of three replicates. *represents a result significantly higher (p < 0.05) than the fluorescence of untreated cells.