Fig. 4.

Rapid pathogen-induced apoptosis in DCs requires p32 function. (A) DCs untreated, treated with siRNA against p32, or mock treated were infected with L. pneumophila ΔflaA, ΔflaA expressing AnkG, or ΔdotA. L. pneumophila were stained with a specific anti-Legionella antibody, and the nuclei of infected cells were scored using DAPI staining. Data shown are from one experiment representative of five independent experiments that yielded similar results. n = 200 MHC class II-positive DCs. (B) DCs untreated (black bars), treated with siRNA against p32 (white bars), or mock treated (gray bars) were infected with L. pneumophila ΔflaA, ΔflaA expressing AnkG, or ΔdotA. Vacuoles containing replicating bacteria at 10 h postinfection were counted. Data shown are from one representative experiment representative of five independent experiments that yielded similar results. n = 200 MHC class II-positive DCs. N.D., vacuoles containing replicating bacteria were not detectable; R.V., vacuoles containing replicating bacteria. (C) DCs treated with p32 siRNA (Right) or mock treated (Left) were infected with L. pneumophila ΔflaA or with L. pneumophila WT. Vacuoles containing replicating bacteria at 10 h postinfection were counted. Data are shown from one experiment representative of two independent experiments that yielded similar results. n = 200 MHC class II-positive DCs.