Recent studies indicate that several Toll-like receptors (TLRs) are implicated in recognizing viral structures and instigating immune responses against viral infections. The aim of this study is to examine the expression of TLRs and proinflammatory cytokines in viral skin diseases such as verruca vulgaris (VV) and molluscum contagiosum (MC). Reverse transcription-polymerase chain reaction and immunostaining of skin samples were performed to determine the expression of specific antiviral and proinflammatory cytokines as well as 5 TLRs (TLR2, 3, 4, 7, and 9). In normal human skin, TLR2, 4, and 7 mRNA was constitutively expressed, whereas little TLR3 and 9 mRNA was detected. Compared to normal skin (NS), TLR3 and 9 mRNA was clearly expressed in VV and MC specimens. Likewise, immunohistochemistry indicated that keratinocytes in NS constitutively expressed TLR2, 4, and 7; however, TLR3 was rarely detected and TLR9 was only weakly expressed, whereas 5 TLRs were all strongly expressed on the epidermal keratinocytes of VV and MC lesions. In addition, the mRNA expression of IFN-beta and TNF-alpha was upregulated in the VV and MC samples. Immunohistochemistry indicated that IFN-beta and TNF-alpha were predominately localized in the granular layer in the VV lesions and adjacent to the MC bodies. Our results indicated that VV and MC skin lesions expressed TLR3 and 9 in addition to IFN-beta and TNF-alpha. These viral-induced proinflammatory cytokines may play a pivotal role in cutaneous innate immune responses.
Cytokines/metabolism ; *Gene Expression Regulation ; Humans ; Immunohistochemistry/methods ; Inflammation ; Interferon-beta/biosynthesis ; Keratinocytes/cytology ; Models, Biological ; Molluscum Contagiosum/*metabolism ; Toll-Like Receptor 3/biosynthesis ; Toll-Like Receptor 9/biosynthesis ; Toll-Like Receptors/*biosynthesis ; Tumor Necrosis Factor-alpha/biosynthesis ; Warts/*metabolism

OBJECTIVETo investigate the effects of tumor necrosis factor alpha (TNF alpha) and interferon gamma (IFN gamma) on the expression of pattern recognition receptors (PRRs) on the surface of mouse alveolar macrophages.

METHODSAlveolar macrophages from mouse were cultured in DMEM supplemented with 10% (V/V) endotoxin-free calf serum. After the alveolar macrophages were stimulated with TNF alpha and IFN gamma (concentration, 20 ng/ml) for 3 h, 6 h and 12 h, the expression of PRRs, including cluster of differentiation 14 (CD14), scavenger receptor (SR), toll-like receptor 4 (TLR4), TLR2 and TLR9 mRNA and proteins were examined by RT-PCR and immunohistochemistry.

RESULTSThe expressions of CD14, TLR2 and TLR9 receptors, which were related with cellular activation, were up-regulated by the stimulation of TNF alpha and IFN gamma (P < 0.05), while SR, which was related with cellular defense action, was down-regulated (P < 0.05). Although the expression of TLR4 was up-regulated, there was no statistical significance (P > 0.05).

CONCLUSIONSThe cytokines such as TNF alpha and IFN gamma could also produce feedback regulation on the expression of PRRs at the levels of genes and proteins. Such regulation on the PRRs expression would be significant for further amplification of inflammation cascade and eventually leading to uncontrolled inflammation.

Animals ; Cells, Cultured ; Interferon-gamma ; pharmacology ; Lipopolysaccharide Receptors ; biosynthesis ; genetics ; Macrophages, Alveolar ; metabolism ; Mice ; RNA, Messenger ; genetics ; Receptors, Pattern Recognition ; biosynthesis ; Toll-Like Receptor 2 ; biosynthesis ; genetics ; Toll-Like Receptor 4 ; biosynthesis ; genetics ; Toll-Like Receptor 9 ; biosynthesis ; genetics ; Tumor Necrosis Factor-alpha ; pharmacology

OBJECTIVE: To determine the role of Toll-like receptor 9 (TLR9) in synthetic oligodeoxynucleotides (ODN) containing unmethylated CpG dinucleotides (CpG-ODN)-induced species-specific immune responses. METHODS: CpG-ODN was co-cultured with peripheral blood mononuclear cells (PBMC) of humans, macaques and mice. The IFN-alpha in the supernatant was measured by ELISA. The reverse transcription PCR was used to analyze the expression levels of TLR9 mRNA in PBMC. RESULTS: CpG-ODN induced high amounts of IFN-alpha in human PBMC, but had no effect on macaques and mice. The expression of TLR9 mRNA was observed in all human PBMC, and the levels of TLR9 mRNA were significantly up-regulated with the stimulation of CpG-ODN. We did not observe any expression of TLR9 mRNA in PBMC in macaques. CONCLUSION TLR9 underlies the molecular foundation of CpG-ODN-induced species specificity.
Animals ; Humans ; Interferon-alpha ; biosynthesis ; Leukocytes, Mononuclear ; cytology ; immunology ; metabolism ; Macaca mulatta ; Mice ; Oligodeoxyribonucleotides ; pharmacology ; Species Specificity ; Toll-Like Receptor 9 ; biosynthesis ; genetics

Toll-like receptors (TLRs) family may play important roles in inflammatory bowel disease. This study examined the expression of TLR2, TLR4 and TLR9 in the colonic tissues of patients with ulcerative colitis (UC) and explored their roles in the pathogenesis of UC. Colonic biopsies were taken from the colon of 30 patients with mild or moderate UC (at active phase) and 10 healthy controls during colonoscopy. TLR2, TLR4 and TLR9 protein expression levels were immunohistochemically detected. The mRNA expression levels of TLR2, TLR4 and TLR9 were assessed by reverse transcription polymerase chain reaction (RT-PCR). The disease activity index (DAI), colonoscopic and histologic grades and fecal microbial flora were determined. Histological examination showed that the intestinal mucous membrane of UC patients underwent acute inflammation changes. Immunohistochemistry exhibited that the expression levels of TLR2, TLR4 and TLR9 in colon epithelia and inflammatory cells were higher in UC patients than in control group (P<0.01). The mRNA expression levels of TLR2, TLR4 and TLR9 were increased in UC patients but were not detected in the normal controls. Expression levels of TLR2, TLR4 and TLR9 were positively correlated, and bore close correlation with DAI, colonoscopic and histologic grades and fecal microbial flora. An important mechanism of UC might be that abnormal activation of mucosal immunity by intestinal dysbacteriosis caused dysregulation of TLRS that mediates innate immunity.
Colitis, Ulcerative ; genetics ; metabolism ; pathology ; Colon ; metabolism ; microbiology ; Colonoscopy ; Feces ; microbiology ; Female ; Gene Expression ; Humans ; Immunohistochemistry ; Intestinal Mucosa ; metabolism ; microbiology ; Male ; Reverse Transcriptase Polymerase Chain Reaction ; Severity of Illness Index ; Toll-Like Receptor 2 ; biosynthesis ; genetics ; Toll-Like Receptor 4 ; biosynthesis ; genetics ; Toll-Like Receptor 9 ; biosynthesis ; genetics

Dendritic cells (DCs) comprise two functionally distinct subsets: plasmacytoid DCs (pDCs) and myeloid DCs (mDCs). pDCs are specialized in rapid and massive secretion of type I interferon (IFN-I) in response to nucleic acids through Toll like receptor (TLR)-7 or TLR-9. In this report, we characterized a CD56(+) DC population that express typical pDC markers including CD123 and BDCA2 but produce much less IFN-I comparing with pDCs. In addition, CD56(+) DCs cluster together with mDCs but not pDCs by genome-wide transcriptional profiling. Accordingly, CD56(+) DCs functionally resemble mDCs by producing IL-12 upon TLR4 stimulation and priming naïve T cells without prior activation. These data suggest that the CD56(+) DCs represent a novel mDC subset mixed with some pDC features. A CD4(+)CD56(+) hematological malignancy was classified as blastic plasmacytoid dendritic cell neoplasm (BPDCN) due to its expression of characteristic molecules of pDCs. However, we demonstrated that BPDCN is closer to CD56(+) DCs than pDCs by global gene-expression profiling. Thus, we propose that the CD4(+)CD56(+) neoplasm may be a tumor counterpart of CD56(+) mDCs but not pDCs.
Biomarkers ; metabolism ; CD56 Antigen ; genetics ; immunology ; Cell Lineage ; genetics ; immunology ; Dendritic Cells ; immunology ; metabolism ; pathology ; Gene Expression ; Hematologic Neoplasms ; genetics ; immunology ; pathology ; Humans ; Immunophenotyping ; Interferon Type I ; biosynthesis ; metabolism ; Interleukin-12 ; biosynthesis ; metabolism ; Interleukin-3 Receptor alpha Subunit ; genetics ; immunology ; Lectins, C-Type ; genetics ; immunology ; Membrane Glycoproteins ; genetics ; immunology ; Myeloid Cells ; immunology ; metabolism ; pathology ; Receptors, Immunologic ; genetics ; immunology ; Terminology as Topic ; Toll-Like Receptor 4 ; genetics ; immunology ; Toll-Like Receptor 7 ; genetics ; immunology ; Toll-Like Receptor 9 ; genetics ; immunology

Unmethylated CpG oligodeoxynucleotides (CpG ODNs) activate immune cells to produce immune mediators. This study demonstrates that in murine macrophage RAW 264.7 cells, CpG ODN-mediated matrix metalloproteinase-9 (MMP-9) expression is regulated at transcriptional level and requires de novo protein synthesis. Inhibition of ERK and p38 MAPK, but not JNK, results in significant decrease of CpG ODN-induced MMP-9 expression. We found that endosomal maturation inhibitors, chloroquine and bafilomycin A, block CpG ODN-induced ERK and p38 MAPK activation and the subsequent MMP-9 expression. We also observed that CpG ODN induces NF-kappa B activation and NF-kappa B is a downstream target of p38 MAPK. Taken together, our data demonstrate that CpG ODN triggers MMP-9 expression via TLR-9 dependent ERK and p38 MAPK activation followed by NF-kappa B activation.
Animals ; Cell Line ; Enzyme Activation/drug effects ; Enzyme Induction/drug effects ; Matrix Metalloproteinase 9/*biosynthesis ; Mice ; Mitogen-Activated Protein Kinase 1/antagonists & inhibitors/metabolism ; Mitogen-Activated Protein Kinase 3/antagonists & inhibitors/metabolism ; Mitogen-Activated Protein Kinases/*metabolism ; NF-kappa B/*metabolism ; Oligodeoxyribonucleotides/*pharmacology ; Signal Transduction/drug effects ; Toll-Like Receptor 9/antagonists & inhibitors/*metabolism ; p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors/metabolism