Toll-like receptor 9 (TLR9) is a pattern-recognition receptor that is involved in immune signaling and plays a crucial role in cell survival through recognition of various bacterial and viral components including unmethylated CpG-DNA. TLR9 expression and function in cancer cells are not well understood. We investigated the expression of TLR9, and the function of TLR9 signaling, in hepatocellula...

Systemic lupus erythematosus is characterized by the production of autoantibodies directed against nuclear Ags, including nucleosome and DNA. TLR9 is thought to play a role in the production of these autoantibodies through the capacity of nuclear immunogenic particles to interact both with BCR and TLR9. To determine the role of TLR9 in SLE, C57BL/6-lpr/lpr-TLR9(-/-) and TLR9(+/+) mice were anal...

Toll-like receptor-9 (TLR9) is a cellular DNA sensor of the innate immune system. TLR9 is widely expressed in a number of tumors, including brain cancer; however, little is known regarding its regulation and involvement in cancer pathophysiology. The present study demonstrated that hypoxia upregulates and downregulates TLR9 expression in human brain cancer cells in vitro, in a cell-specific man...

BACKGROUND Bacterial meningitis (BM) is a severe infection mainly caused by Streptococcus pneumoniae and Neisseria meningitidis (NM). However, genetically determined susceptibility to develop severe infections by these microorganisms is variable between individuals. Toll-like receptor 9 (TLR9) recognizes bacterial DNA leading to intracellular inflammatory signaling. Single nucleotide polymorphi...

OBJECTIVES Toll-like receptor 9 (TLR9) is a pattern-associated receptor functioning in innate immunity that may be involved in the recognition of self-antigens and the production of pathogenic auto-antibodies. Therefore, we examined the expression of TLR9 in systemic lupus erythematosus (SLE) to determine whether TLR9 is involved in the production of pathogenic auto-antibodies. METHODS B cell...

Toll-like receptor-9 (TLR9) is a member of the innate immune system and recognizes bacterial and vertebrate DNA in cells. In addition to being expressed in cells of the immune system, it is widely expressed in various types of human cancer, including prostate cancer. We have previously demonstrated that synthetic TLR9 ligands induce invasion in TLR9-expressing prostate cancer cells in vitro. Ho...

Toll-like receptor 9 (TLR9) senses bacterial DNA characteristic of unmethylated CpG motifs to induce innate immune response. TLR9 is de novo expressed in podocytes of some patients with glomerular diseases, but its role in podocyte injury remains undetermined. Since TLR9 activates p38 MAPK and NFkB that are known to mediate podocyte apoptosis, we hypothesized that TLR9 induces podocyte apoptosi...

Toll-like receptor 9 (TLR9) recognizes microbial DNA in endolysosomal compartments. The ectodomain of TLR9 must be proteolytically cleaved by endosomal proteases to produce the active receptor capable of inducing an innate immune signal. We show that the cleaved TLR9 ectodomain is a monomer in solution and that DNA ligands with phosphodiester backbones induce TLR9 dimerization in a sequence-ind...

Toll-like Receptor 9 (TLR9) is an innate immune receptor recognizing microbial DNA. TLR9 is also activated by self-derived DNA, such as mitochondrial DNA, in a variety of inflammatory diseases. We show here that TLR9 activation in vivo is controlled by an anti-TLR9 monoclonal Ab (mAb). A newly established mAb, named NaR9, clearly detects endogenous TLR9 expressed in primary immune cells. The mA...

Toll-like receptor 9 (TLR9) recognizes microbial and vertebrate DNA. We previously demonstrated TLR9 expression in human breast cancer cell lines and showed that TLR9 ligands stimulate their in vitro invasion. The aim of this study was to characterize TLR9 expression in clinical breast cancer specimens. Immunohistochemical staining intensity was compared with known baseline prognostic factors a...