Figure 4: F. novicida and mutant strains replication in A549 lung epithelial cells. Bacterial localization was determined by immunofluorescence staining with a fluorescently labeled antibody against F. novicida LPS (green). Nuclei were stained with DAPI (blue). Images shown are F. novicida (U112) (A), ΔiglC (B), Δtul4 (C), ΔmglA(D) and Δ58kDa (E). Panels A through E were merged to DIC images. 400X. Representative images are from 24 hrs of replication.