RRC ID 47509
Author Inoue R, Nagino T, Hoshino G, Ushida K.
Title Nucleic acids of Enterococcus faecalis strain EC-12 are potent Toll-like receptor 7 and 9 ligands inducing interleukin-12 production from murine splenocytes and murine macrophage cell line J774.1.
Journal FEMS Immunol Med Microbiol
Abstract In experiment 1 of this study, the interleukin-12 (IL-12)-inducing ability of six Enterococcus strains was evaluated in comparison with that of five Lactobacillus strains using murine splenocytes. At the same time, the involvement of Toll-like receptor (TLR) ligands in IL-12-inducing ability was assessed using splenocytes from TLR2-, TLR4- and MyD88-deficient mice. Most Enterococcus strains, especially Enterococcus faecalis strain EC-12, exerted higher IL-12-inducing ability compared with the Lactobacillus strains evaluated. Almost the same amount of IL-12 protein was produced by all lactic acid bacteria strains in splenocytes from TLR2- and TLR4-deficient mice, whereas splenocytes from MyD88-deficient mice showed no IL-12 production against all bacteria evaluated. In experiment 2, the role of TLR7, 8 and 9 ligands of E. faecalis strain EC-12 in the induction of IL-12 production was evaluated using murine macrophage cell line J774.1. A drastic decrease in IL-12-inducing ability was observed when heat-killed E. faecalis strain EC-12 was treated with nuclease, particularly RNase. In addition, less than one-tenth of IL-12 was produced by heat-killed E. faecalis strain EC-12 when both TLR7 and 9 were antagonized. These facts indicate that the nucleic acids of E. faecalis strain EC-12, particularly its RNA, are the potent TLR7 and 9 ligands that induce IL-12 production from antigen-presenting cells.
Volume 61(1)
Pages 94-102
Published 2011-2-1
DOI 10.1111/j.1574-695X.2010.00752.x
PMID 21073545
MeSH Animals Antigen-Presenting Cells / immunology Cell Line DNA, Bacterial / immunology Enterococcus faecalis / genetics* Interleukin-12 / immunology* Ligands* Mice Mice, Inbred C57BL Mice, Knockout Myeloid Differentiation Factor 88 / immunology Nucleic Acids / immunology* RNA, Bacterial / immunology Signal Transduction / immunology Spleen / immunology* Toll-Like Receptors / immunology*
Times Cited 16
General Microbes JCM 8714 JCM 8727 JCM 1132 JCM 1134 JCM 5344 JCM 1149