Activation of Type III Interferon Genes by Pathogenic Bacteria in Infected Epithelial Cells and Mouse Placenta (original) (raw)
Figure 2
Induction of IFN-III genes by different bacterial species in epithelial cells.
A. LoVo intestinal cells infected with S. enterica at multiplicity of infection (MOI) of 20 for the indicated time, were lysed and processed for quantification of intracellular bacterial by counting colony-forming units (CFU) on agar plates, or for total cellular RNA extraction and quantification of IFN gene expression, as described for L. monocytogenes in Figure 1A. Values from three independent experiments are expressed as mean ± S.D. of the fold change relative to uninfected control cell values at the beginning of the experiment. B. LoVo cells, uninfected or infected for 18 h with different bacterial species, were processed for quantification of bacterial load and mRNA. Quantification of internalized bacteria: data are means ± S.D. of CFU for 105 cells (n = 3) at the indicated MOI, except for C. trachomatis, for which the percentage of infected cells (n = 4) were determined by flow cytometry after antibody labelling (see text). IFN-λ1 and IFN-λ2 transcript levels were determined by qRT-PCR and normalized to GAPDH transcript levels. Values are expressed as mean ± S.D. of the fold change relative to that in uninfected cells (n = 3 to 5). C. Quantification of IFN-λ1/λ3 and IL-8 production were done by ELISA, using culture supernatants of LoVo cells infected for 28 h with the indicated bacterium at a MOI of 50. Experiments were done in triplicates and reproduced once. D. Quantification of IFN-λ mRNAs in A549 lung epithelial cells infected with _GFP_-expressing M. tuberculosis (n = 4). The percentage of infected cells were determined by flow cytometry (see text).