Ogenes (Fig. 4B; Fig. S4A). By contrast, in THP1 cells, which can recognize bacDNA and bacRNA, form I IFN induction did not seem to be influenced byPLOS One particular | www.plosone.orgRIGI Detects RNA of Listeria in NonImmune CellsFigure 3. Recognition of bacterial RNA or DNA varies for distinctive cell types. A: THP1 and A549 cells have been transfected with double stranded triphosphorylated RNA (3PdsRNA), poly(dAdT), bacterial DNA (bacDNA), plasmid DNA (pDNA) or double stranded 84 mer DNA oligonucleotides (dsODN); B: THP1, A549, HepG2 and Colo205 cells were transfected with L. monocytogenes RNA, L. monocytogenes DNA or 3PdsRNA. Variety I IFN (THP1, A549, Colo205) or CXCL10 (HepG2) production was analyzed 24 hours soon after stimulation. The relative induction of your indicated cytokine is depicted as percentage of induction by transfected L. monocytogenes (L.M.) RNA. C, D, E and F: THP1, A549, HepG2 and Colo205 cells were infected with wt and hly L. monocytogenes in the indicated MOI. Form I IFN (THP1, A549, Colo205) or CXCL10 production (HepG2) was analyzed 24 hours immediately after stimulation. Error bars represent s.d. doi:ten.1371/journal.pone.0062872.gnot raise a type I IFN response upon transfection of bacDNA, despite a robust response to poly(dAdT), indicating the absence of functional STINGdependent recognition pathways. The latter getting also excludes an involvement from the pol III/RIGI dependent pathway of bacDNA detection as suggested by Chu et al. [24] but corroborates information of Monroe et al. [59] for L. pneumophila bacterial DNA, which was shown not to trigger the pol III/RIGI dependent pathway. Regardless of translocation of bacRNA into the cytosol, RNAi of RIGI or MAVS in monocytic cells (THP1) didn’t impair type I IFN induction throughout infection with L. monocytogenes. This suggests a redundant role of RIGI regarding variety I IFN induction inmonocytes through L. monocytogenes infection, as shown for L. pneumophila [59]. The minor contribution of your RIGI/MAVS pathway in monocytic cells may perhaps be due to a dominance in concentration or impact of other stimuli released by L. monocytogenes, like bacDNA or the recently found mediator cyclic diadenosine monophosphate (cdiAMP) [34]. By contrast, induction of type I IFN during L. monocytogenes infection of epithelial cells was practically completely abolished by RNAimediated knockdown of RIGI or MAVS, implicating that neither DNA nor cdiAMP plays a part for L. monocytogenes mediated sort I IFN induction in these cells. With each other, we conclude that RIGI plays a major function inside the L.4-Iodopyridine Order monocytogenesPLOS 1 | www.494767-19-0 site plosone.PMID:23907521 orgRIGI Detects RNA of Listeria in NonImmune CellsFigure 4. Knockdown of RIGI abrogates L. monocytogenesinduced form I IFN induction in epithelial but not in monocytic cells. A: Murine BMDCs have been transfected with indicated stimuli. One particular out of two experiments is shown. Murine IFNa secretion was analyzed 24 hours immediately after stimulation. Error bars represent SEM. B: A549 cells had been transfected with siRNA against RIGI, MAVS or Luciferase (handle). Cells had been then infected with L. monocytogenes or transfected with L. monocytogenes RNA (L.m. RNA), L. monocytogenes DNA (L.m. RNA) or 3PdsRNA 48 hours soon after knockdown. Form I IFN production was analyzed 24 hours soon after stimulation. B) THP1 cells were electroporated with control siRNA or siRNAs against MAVS or STING. 72 hours following electroporation, THP1 cells were infected with hly or wt L. monocytogenes at indicated MOI or transfected with plasmid DNA (pDNA) or RIGI ligand (3P.
