FIG 6.

Evaluation of the ability of huscFv1E4 to inhibit C. burnetii infection in THP-1 differentiated human macrophages by comparing infection rate and C. burnetii genomic numbers with values of PBS and IgG2a isotype control treatment at 1 day postinfection (dpi). (A) IFA staining of human macrophages infected with PBS-, IgG2a isotype-, or huscFv1E4-treated C. burnetii. Host nuclei were stained by DAPI fluorescence (blue); intracellular C. burnetii was stained with rabbit anti-Nine Mile phase II/NMI polyclonal antibodies, followed by incubation with 10 μg/ml FITC-labeled goat anti-rabbit IgG (green, FITC-labeled NMI cells). (B) C. burnetii infection rate was determined by IFA, represented as a percentage of cells containing more than 5 organisms. A total of 200 cells were counted per sample to determine the infection rate. (C) C. burnetii genomic number was determined by real-time PCR. The data presented in each group in panels B and C are the averages with standard deviations from duplicate samples. ***, P < 0.001.