FIG. 4.

(A) C. pneumoniae (C. pneu.) reduced PDTC-derived apoptosis in Mono Mac 6 cells, which correlates with NF-κB binding activity. Mono Mac 6 cells were treated with PDTC (10⁻⁴ M) for 10 h and/or with C. pneumoniae at an MOI of 5 for 9 h as indicated. Flow cytometric analysis of apoptotic cells using annexin V-FITC is shown. Cells were incubated with annexin V-FITC in a buffer containing propidium iodide (PI) and were analyzed by flow cytometry. PI-negative cells were gated (top). For electromobility shift assay, nuclear extracts were prepared and equal amounts were reacted with ³²P-labeled DNA probe encompassing the κB motif of the mouse kappa light chain enhancer. The arrow indicates the position of the κB-specific DNA binding activity (bottom). Data are representative examples of three similar experiments. (B) Relative NF-κB binding activity of Mono Mac 6 cells, which were treated with PDTC (10⁻⁴ M) for 10 h and/or C. pneumoniae at an MOI of 5 for 9 h, obtained from densitometric analysis. Scans from EMSAs were analyzed by using the NIH Image software. The density of the NF-κB complex of the untreated cells was set as 1. P values were determined by Student's t test and are indicated by asterisks (n = 3). ∗, P < 0.05; ∗∗, P < 0.005.