Nonalcoholic steatohepatitis (NASH) is the most common liver disease in industrialized countries. NASH is a progressive disease that can lead to cirrhosis, cancer, and death, and there are currently no approved therapies. The development of NASH in animal models requires intact TLR9, but how the TLR9 pathway is activated in NASH is not clear. Our objectives in this study were to identify NASH-a...

TLRs expressed by a variety of cells, including epithelial cells, B cells, and dendritic cells, are important initiators of the immune response following stimulation with various microbial products. Several of the TLRs require the adaptor protein, MyD88, which is an important mediator for the immune response following Toxoplasma gondii infection. Previously, TLR9-mediated innate immune response...

Toll-like receptor 9 (TLR9) recognizes microbial DNA. We show here that TLR9 protein is expressed in human breast cancer cells and clinical breast cancer samples. Stimulation of TLR9-expressing breast cancer cells with the TLR9 agonistic CpG oligonucleotides (1-10 mumol/L) dramatically increased their in vitro invasion in both Matrigel assays and three-dimensional collagen cultures. Similar eff...

TLR signaling is essential to innate immunity against microbial invaders and must be tightly controlled. We have previously shown that TLR9 undergoes proteolytic cleavage processing by lysosomal proteases to generate two distinct fragments. The C-terminal cleavage product plays a critical role in activating TLR9 signaling; however, the precise role of the N-terminal fragment, which remains in l...

The human toll like receptor 9 (TLR9) detects differences between microbial and host DNA, based on unmethylated deoxycytidyl deoxyguanosine dinucleotide (CpG) motifs, leading to activation of both innate and adaptive immune mechanisms. The synthetic TLR9 agonist, CpG-ODN, can substitute for microbial DNA in these responses, and is in clinical trials as an immunomodulatory agent in diseases as d...

Diabetogenic CD8(+) T cells are primed in the pancreatic lymph nodes (PLNs) by dendritic cells (DCs) carrying islet cell Ags. TLR signaling modifies DC function. The goal of this study was to determine the effect of TLR9 signaling on diabetogenic CD8(+) T cell activation and the course of type 1 diabetes. We explored the effects of CpG oligonucleotide, TLR9 antagonists, and genetic TLR9 deficie...

In its vertebrate host, Leishmania encounters cells that express TLRs. Using genetically resistant C57BL/6 mice deficient in either TLR2, 4, or 9, we show in this study that only TLR9-deficient mice are more susceptible to infection with Leishmania major. TLR9-deficient mice resolved their lesions and controlled parasites growth with much lower efficiency than wild-type C57BL/6 mice. The absenc...

To investigate the correlation between TLR9 and cytokine secretion in SLE diagnosis and treatment. A total of 66 cases (39 SLE and 27 healthy donors) were enrolled in this study. The CD20+ labeled B cells were isolated from SLE patients. TLR9 mRNA expression from SLE tissues and B cells was detected using RT-PCR. The cytokine secretion in B cells were measured using ELISA. Correlation between T...

Intestinal Peyer's patch (PP) regulatory CD21+ B cells (B(regs)) suppress TLR9-induced innate immune responses. However, it is not known whether TLR9 activation is regulated in PP B(regs). Here, we investigated the responses of PP B(regs) to stimulation with the TLR9 agonist CpG oligodeoxynucleotides (ODN). We observed that PP CD21+ B(regs) express high levels of TLR9 mRNA, but fail to prolifer...