WorldWideScience

Sample records for tenella derived tlr

  1. A new adenovirus based vaccine vector expressing an Eimeria tenella derived TLR agonist improves cellular immune responses to an antigenic target.

    Directory of Open Access Journals (Sweden)

    Daniel M Appledorn

    2010-03-01

    Full Text Available Adenoviral based vectors remain promising vaccine platforms for use against numerous pathogens, including HIV. Recent vaccine trials utilizing Adenovirus based vaccines expressing HIV antigens confirmed induction of cellular immune responses, but these responses failed to prevent HIV infections in vaccinees. This illustrates the need to develop vaccine formulations capable of generating more potent T-cell responses to HIV antigens, such as HIV-Gag, since robust immune responses to this antigen correlate with improved outcomes in long-term non-progressor HIV infected individuals.In this study we designed a novel vaccine strategy utilizing an Ad-based vector expressing a potent TLR agonist derived from Eimeria tenella as an adjuvant to improve immune responses from a [E1-]Ad-based HIV-Gag vaccine. Our results confirm that expression of rEA elicits significantly increased TLR mediated innate immune responses as measured by the influx of plasma cytokines and chemokines, and activation of innate immune responding cells. Furthermore, our data show that the quantity and quality of HIV-Gag specific CD8(+ and CD8(- T-cell responses were significantly improved when coupled with rEA expression. These responses also correlated with a significantly increased number of HIV-Gag derived epitopes being recognized by host T cells. Finally, functional assays confirmed that rEA expression significantly improved antigen specific CTL responses, in vivo. Moreover, we show that these improved responses were dependent upon improved TLR pathway interactions.The data presented in this study illustrate the potential utility of Ad-based vectors expressing TLR agonists to improve clinical outcomes dependent upon induction of robust, antigen specific immune responses.

  2. An Eimeria vaccine candidate based on Eimeria tenella immune mapped protein 1 and the TLR-5 agonist Salmonella typhimurium FliC flagellin

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Guangwen; Qin, Mei [National Animal Protozoa Laboratory and College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); Liu, Xianyong [National Animal Protozoa Laboratory and College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); Key Laboratory of Zoonosis, China Ministry of Agriculture and College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); Suo, Jingxia; Tang, Xinming; Tao, Geru [National Animal Protozoa Laboratory and College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); Han, Qian [Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061 (United States); Suo, Xun [National Animal Protozoa Laboratory and College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); Key Laboratory of Zoonosis, China Ministry of Agriculture and College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); Wu, Wenxue, E-mail: labboard@126.com [National Animal Protozoa Laboratory and College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China); Key Laboratory of Zoonosis, China Ministry of Agriculture and College of Veterinary Medicine, China Agricultural University, Beijing 100193 (China)

    2013-10-25

    Highlights: •We found a new protective protein – (IMPI) in Eimeria tenella. •EtIMP1-flagellin fusion protein is an effective immunogen against Eimeria infection. •Flagellin can be as an apicomplexan parasite vaccine adjuvant in chickens. -- Abstract: Immune mapped protein-1 (IMP1) is a new protective protein in apicomplexan parasites, and exits in Eimeria tenella. But its structure and immunogenicity in E. tenella are still unknown. In this study, IMPI in E. tenella was predicted to be a membrane protein. To evaluate immunogenicity of IMPI in E. tenella, a chimeric subunit vaccine consisting of E. tenella IMP1 (EtIMP1) and a molecular adjuvant (a truncated flagellin, FliC) was constructed and over-expressed in Escherichia coli and its efficacy against E. tenella infection was evaluated. Three-week-old AA broiler chickens were vaccinated with the recombinant EtIMP1-truncated FliC without adjuvant or EtIMP1 with Freund’s Complete Adjuvant. Immunization of chickens with the recombinant EtIMP1-truncated FliC fusion protein resulted in stronger cellular immune responses than immunization with only recombinant EtIMP1 with adjuvant. The clinical effect of the EtIMP1-truncated FliC without adjuvant was also greater than that of the EtIMP1 with adjuvant, which was evidenced by the differences between the two groups in body weight gain, oocyst output and caecal lesions of E. tenella-challenged chickens. The results suggested that the EtIMP1-flagellin fusion protein can be used as an effective immunogen in the development of subunit vaccines against Eimeria infection. This is the first demonstration of antigen-specific protective immunity against avian coccidiosis using a recombinant flagellin as an apicomplexan parasite vaccine adjuvant in chickens.

  3. An Eimeria vaccine candidate based on Eimeria tenella immune mapped protein 1 and the TLR-5 agonist Salmonella typhimurium FliC flagellin

    International Nuclear Information System (INIS)

    Yin, Guangwen; Qin, Mei; Liu, Xianyong; Suo, Jingxia; Tang, Xinming; Tao, Geru; Han, Qian; Suo, Xun; Wu, Wenxue

    2013-01-01

    Highlights: •We found a new protective protein – (IMPI) in Eimeria tenella. •EtIMP1-flagellin fusion protein is an effective immunogen against Eimeria infection. •Flagellin can be as an apicomplexan parasite vaccine adjuvant in chickens. -- Abstract: Immune mapped protein-1 (IMP1) is a new protective protein in apicomplexan parasites, and exits in Eimeria tenella. But its structure and immunogenicity in E. tenella are still unknown. In this study, IMPI in E. tenella was predicted to be a membrane protein. To evaluate immunogenicity of IMPI in E. tenella, a chimeric subunit vaccine consisting of E. tenella IMP1 (EtIMP1) and a molecular adjuvant (a truncated flagellin, FliC) was constructed and over-expressed in Escherichia coli and its efficacy against E. tenella infection was evaluated. Three-week-old AA broiler chickens were vaccinated with the recombinant EtIMP1-truncated FliC without adjuvant or EtIMP1 with Freund’s Complete Adjuvant. Immunization of chickens with the recombinant EtIMP1-truncated FliC fusion protein resulted in stronger cellular immune responses than immunization with only recombinant EtIMP1 with adjuvant. The clinical effect of the EtIMP1-truncated FliC without adjuvant was also greater than that of the EtIMP1 with adjuvant, which was evidenced by the differences between the two groups in body weight gain, oocyst output and caecal lesions of E. tenella-challenged chickens. The results suggested that the EtIMP1-flagellin fusion protein can be used as an effective immunogen in the development of subunit vaccines against Eimeria infection. This is the first demonstration of antigen-specific protective immunity against avian coccidiosis using a recombinant flagellin as an apicomplexan parasite vaccine adjuvant in chickens

  4. Induction of Protective Immunity against Eimeria tenella, Eimeria maxima, and Eimeria acervulina Infections Using Dendritic Cell-Derived Exosomes

    Science.gov (United States)

    Gallego, Margarita; Lee, Sung Hyen; Lillehoj, Hyun Soon; Quilez, Joaquin; Lillehoj, Erik P.; Sánchez-Acedo, Caridad

    2012-01-01

    This study describes a novel immunization strategy against avian coccidiosis using exosomes derived from Eimeria parasite antigen (Ag)-loaded dendritic cells (DCs). Chicken intestinal DCs were isolated and pulsed in vitro with a mixture of sporozoite-extracted Ags from Eimeria tenella, E. maxima, and E. acervulina, and the cell-derived exosomes were isolated. Chickens were nonimmunized or immunized intramuscularly with exosomes and subsequently noninfected or coinfected with E. tenella, E. maxima, and E. acervulina oocysts. Immune parameters compared among the nonimmunized/noninfected, nonimmunized/infected, and immunized/infected groups were the numbers of cells secreting Th1 cytokines, Th2 cytokines, interleukin-16 (IL-16), and Ag-reactive antibodies in vitro and in vivo readouts of protective immunity against Eimeria infection. Cecal tonsils, Peyer's patches, and spleens of immunized and infected chickens had increased numbers of cells secreting the IL-16 and the Th1 cytokines IL-2 and gamma interferon, greater Ag-stimulated proliferative responses, and higher numbers of Ag-reactive IgG- and IgA-producing cells following in vitro stimulation with the sporozoite Ags compared with the nonimmunized/noninfected and nonimmunized/infected controls. In contrast, the numbers of cells secreting the Th2 cytokines IL-4 and IL-10 were diminished in immunized and infected chickens compared with the nonimmunized/noninfected and the nonimmunized/infected controls. Chickens immunized with Ag-loaded exosomes and infected in vivo with Eimeria oocysts had increased body weight gains, reduced feed conversion ratios, diminished fecal oocyst shedding, lessened intestinal lesion scores, and reduced mortality compared with the nonimmunized/infected controls. These results suggest that successful field vaccination against avian coccidiosis using exosomes derived from DCs incubated with Ags isolated from Eimeria species may be possible. PMID:22354026

  5. Pam2 lipopeptides systemically increase myeloid-derived suppressor cells through TLR2 signaling

    Energy Technology Data Exchange (ETDEWEB)

    Maruyama, Akira; Shime, Hiroaki, E-mail: shime@med.hokudai.ac.jp; Takeda, Yohei; Azuma, Masahiro; Matsumoto, Misako; Seya, Tsukasa, E-mail: seya-tu@pop.med.hokudai.ac.jp

    2015-02-13

    Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells that exhibit potent immunosuppressive activity. They are increased in tumor-bearing hosts and contribute to tumor development. Toll-like receptors (TLRs) on MDSCs may modulate the tumor-supporting properties of MDSCs through pattern-recognition. Pam2 lipopeptides represented by Pam2CSK4 serve as a TLR2 agonist to exert anti-tumor function by dendritic cell (DC)-priming that leads to NK cell activation and cytotoxic T cell proliferation. On the other hand, TLR2 enhances tumor cell progression/invasion by activating tumor-infiltrating macrophages. How MDSCs respond to TLR2 agonists has not yet been determined. In this study, we found intravenous administration of Pam2CSK4 systemically up-regulated the frequency of MDSCs in EG7 tumor-bearing mice. The frequency of tumor-infiltrating MDSCs was accordingly increased in response to Pam2CSK4. MDSCs were not increased by Pam2CSK4 stimuli in TLR2 knockout (KO) mice. Adoptive transfer experiments using CFSE-labeled MDSCs revealed that the TLR2-positive MDSCs survived long in tumor-bearing mice in response to Pam2CSK4 treatment. Since the increased MDSC population sustained immune-suppressive properties, our study suggests that Pam2CSK4-triggered TLR2 activation enhances the MDSC potential and suppress antitumor immune response in tumor microenvironment. - Highlights: • Pam2CSK4 administration induces systemic accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • TLR2 is essential for Pam2CSK4-induced accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • Pam2CSK4 supports survival of CD11b{sup +}Gr1{sup +} MDSCs in vivo.

  6. A Novel Interaction Between the TLR7 and a Colchicine Derivative Revealed Through a Computational and Experimental Study

    Directory of Open Access Journals (Sweden)

    Francesco Gentile

    2018-02-01

    Full Text Available The Toll-Like Receptor 7 (TLR7 is an endosomal membrane receptor involved in the innate immune system response. Its best-known small molecule activators are imidazoquinoline derivatives such as imiquimod (R-837 and resiquimod (R-848. Recently, an interaction between R-837 and the colchicine binding site of tubulin was reported. To investigate the possibility of an interaction between structural analogues of colchicine and the TLR7, a recent computational model for the dimeric form of the TLR7 receptor was used to determine a possible interaction with a colchicine derivative called CR42-24, active as a tubulin polymerization inhibitor. The estimated values of the binding energy of this molecule with respect to the TLR7 receptor were comparable to the energies of known binders as reported in a previous study. The binding to the TLR7 was further assessed by introducing genetic transformations in the TLR7 gene in cancer cell lines and exposing them to the compound. A negative shift of the IC50 value in terms of cell growth was observed in cell lines carrying the mutated TLR7 gene. The reported study suggests a possible interaction between TLR7 and a colchicine derivative, which can be explored for rational design of new drugs acting on this receptor by using a colchicine scaffold for additional modifications.

  7. Lipopolysaccharide induces proliferation and osteogenic differentiation of adipose-derived mesenchymal stromal cells in vitro via TLR4 activation

    Energy Technology Data Exchange (ETDEWEB)

    Herzmann, Nicole; Salamon, Achim [Department of Cell Biology, University Medicine Rostock, Schillingallee 69, D-18057 Rostock (Germany); Fiedler, Tomas [Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, Schillingallee 70, D-18057 Rostock (Germany); Peters, Kirsten, E-mail: kirsten.peters@med.uni-rostock.de [Department of Cell Biology, University Medicine Rostock, Schillingallee 69, D-18057 Rostock (Germany)

    2017-01-01

    Multipotent mesenchymal stromal cells (MSC) are capable of multi-lineage differentiation and support regenerative processes. In bacterial infections, resident MSC can come intocontact with and need to react to bacterial components. Lipopolysaccharide (LPS), a typical structure of Gram-negative bacteria, increases the proliferation and osteogenic differentiation of MSC. LPS is usually recognized by the toll-like receptor (TLR) 4 and induces pro-inflammatory reactions in numerous cell types. In this study, we quantified the protein expression of TLR4 and CD14 on adipose-derived MSC (adMSC) in osteogenic differentiation and investigated the effect of TLR4 activation by LPS on NF-κB activation, proliferation and osteogenic differentiation of adMSC. We found that TLR4 is expressed on adMSC whereas CD14 is not, and that osteogenic differentiation induced an increase of the amount of TLR4 protein whereas LPS stimulation did not. Moreover, we could show that NF-κB activation via TLR4 occurs upon LPS treatment. Furthermore, we were able to show that competitive inhibition of TLR4 completely abolished the stimulatory effect of LPS on the proliferation and osteogenic differentiation of adMSC. In addition, the inhibition of TLR4 leads to the complete absence of osteogenic differentiation of adMSC, even when osteogenically stimulated. Thus, we conclude that LPS induces proliferation and osteogenic differentiation of adMSC in vitro through the activation of TLR4 and that the TLR4 receptor seems to play a role during osteogenic differentiation of adMSC.

  8. Microglial-derived miRNA let-7 and HMGB1 contribute to ethanol-induced neurotoxicity via TLR7.

    Science.gov (United States)

    Coleman, Leon G; Zou, Jian; Crews, Fulton T

    2017-01-25

    Toll-like receptor (TLR) signaling is emerging as an important component of neurodegeneration. TLR7 senses viral RNA and certain endogenous miRNAs to initiate innate immune responses leading to neurodegeneration. Alcoholism is associated with hippocampal degeneration, with preclinical studies linking ethanol-induced neurodegeneration with central innate immune induction and TLR activation. The endogenous miRNA let-7b binds TLR7 to cause neurodegeneration. TLR7 and other immune markers were assessed in postmortem human hippocampal tissue that was obtained from the New South Wales Tissue Bank. Rat hippocampal-entorhinal cortex (HEC) slice culture was used to assess specific effects of ethanol on TLR7, let-7b, and microvesicles. We report here that hippocampal tissue from postmortem human alcoholic brains shows increased expression of TLR7 and increased microglial activation. Using HEC slice culture, we found that ethanol induces TLR7 and let-7b expression. Ethanol caused TLR7-associated neuroimmune gene induction and initiated the release let-7b in microvesicles (MVs), enhancing TLR7-mediated neurotoxicity. Further, ethanol increased let-7b binding to the danger signaling molecule high mobility group box-1 (HMGB1) in MVs, while reducing let-7 binding to classical chaperone protein argonaute (Ago2). Flow cytometric analysis of MVs from HEC media and analysis of MVs from brain cell culture lines found that microglia were the primary source of let-7b and HMGB1-containing MVs. Our results identify that ethanol induces neuroimmune pathology involving the release of let-7b/HMGB1 complexes in microglia-derived microvesicles. This contributes to hippocampal neurodegeneration and may play a role in the pathology of alcoholism.

  9. Eimeria tenella: host specificity in gallinaceous birds.

    Science.gov (United States)

    Vetterling, J M

    1976-02-01

    Eight species representing 8 genera of gallinaceous birds were used: Alectoris graeca; Colinus virginianus; Coturnix coturnix; Gallus gallus; Meleagris gallopavo; Numidia meleagris; Pavo cristatus; Phasianus colchicus. Three week-old birds were dosed with sporulated oocysts of Eimeria tenella Beltsville strain. At 4, 24, 48, 72, 96, 120 and 144, and 168 hr after inoculation, 1-3 infected birds and uninoculated controls of each species were killed by cardiac exsanguination. Pieces of intestines were fixed and examined for stages of E. tenella as stained paraffin sections or indirect fluorescent antibody preparations. Oocyst counts were made in droppings collected for the first 6 days of the patent period. Sporozoites were found in the lamina propria of some birds of 5 species at 4 hr postinoculation, but no stages were found thereafter except in the breeds of G. gallus and A. gracea. At 144 and 168 hr postinoculation, a few macrogametes were found in the ceca of 2 A. gracea, but no oocysts were found in the feces. No statistical difference was found between the number of oocysts produced/bird in the breeds of G. gallus examined. It is evident from these observations the E. tenella did not complete its life cycle in several close phylogenetic relatives of G. gallus, even though in other studies this parasite was found to complete its life cycle in cell cultures derived from the same birds.

  10. Impaired intrinsic immunity to HSV-1 in human iPSC-derived TLR3-deficient CNS cells

    Science.gov (United States)

    Lafaille, Fabien G; Pessach, Itai M.; Zhang, Shen-Ying; Ciancanelli, Michael J.; Herman, Melina; Abhyankar, Avinash; Ying, Shui-Wang; Keros, Sotirios; Goldstein, Peter A.; Mostoslavsky, Gustavo; Ordovas-Montanes, Jose; Jouanguy, Emmanuelle; Plancoulaine, Sabine; Tu, Edmund; Elkabetz, Yechiel; Al-Muhsen, Saleh; Tardieu, Marc; Schlaeger, Thorsten M.; Daley, George Q.; Abel, Laurent; Casanova, Jean-Laurent; Studer, Lorenz; Notarangelo, Luigi D.

    2012-01-01

    In the course of primary infection with herpes simplex virus 1 (HSV-1), children with inborn errors of TLR3 immunity are prone to HSV-1 encephalitis (HSE) 1–3. We tested the hypothesis that the pathogenesis of HSE involves non hematopoietic central nervous system (CNS)-resident cells. We derived induced pluripotent stem cells (iPSCs) from the dermal fibroblasts of TLR3- and UNC-93B-deficient patients and from controls. These iPSCs were differentiated into highly purified populations of neural stem cells (NSCs), neurons, astrocytes and oligodendrocytes. The induction of IFN-β and/or IFN-γ1 in response to poly(I:C) stimulation was dependent on TLR3 and UNC-93B in all cells tested. However, the induction of IFN-β and IFN-γ1 in response to HSV-1 infection was impaired selectively in UNC-93B-deficient neurons and oligodendrocytes. These cells were also much more susceptible to HSV-1 infection than control cells, whereas UNC-93B-deficient NSCs and astrocytes were not. TLR3-deficient neurons were also found to be susceptible to HSV-1 infection. The rescue of UNC-93B- and TLR3-deficient cells with the corresponding wild-type allele demonstrated that the genetic defect was the cause of the poly(I:C) and HSV-1 phenotypes. The viral infection phenotype was further rescued by treatment with exogenous IFN-α/β, but not IFN-γ1.Thus, impaired TLR3- and UNC-93B-dependent IFN-α/β intrinsic immunity to HSV-1 in the CNS, in neurons and oligodendrocytes in particular, may underlie the pathogenesis of HSE in children with TLR3 pathway deficiencies. PMID:23103873

  11. The rhoptry proteome of Eimeria tenella sporozoites

    KAUST Repository

    Oakes, Richard D.; Kurian, Dominic; Bromley, Elizabeth V.; Ward, Chris; Lal, Kalpana; Blake, Damer P.; Reid, Adam James; Pain, Arnab; Sinden, Robert E.; Wastling, Jonathan M.; Tomley, F. M. M Fiona

    2013-01-01

    Proteins derived from the rhoptry secretory organelles are crucial for the invasion and survival of apicomplexan parasites within host cells. The rhoptries are club-shaped organelles that contain two distinct subpopulations of proteins that localise to separate compartments of the organelle. Proteins from the neck region (rhoptry neck proteins, RON) are secreted early in invasion and a subset of these is critical for the formation and function of the moving junction between parasite and host membranes. Proteins from the bulb compartment (rhoptry protein, ROP) are released later, into the nascent parasitophorous vacuole where they have a role in modifying the vacuolar environment, and into the host cell where they act as key determinants of virulence through their ability to interact with host cell signalling pathways, causing an array of downstream effects. In this paper we present the results of an extensive proteomics analysis of the rhoptry organelles from the coccidian parasite, Eimeria tenella, which is a highly pathogenic parasite of the domestic chicken causing severe caecal coccidiosis. Several different classes of rhoptry protein have been identified. First are the RON proteins that have varying degrees of similarity to proteins of Toxoplasma gondii and Neospora caninum. For some RON families, E. tenella expresses more than one gene product and many of the individual RON proteins are differentially expressed between the sporozoite and merozoite developmental stages. The E. tenella sporozoite rhoptry expresses only a limited repertoire of proteins with homology to known ROP proteins from other coccidia, including just two secreted ROP kinases, both of which appear to be equipped for catalytic activity. Finally, a large number of hitherto undescribed proteins that map to the sporozoite rhoptry are identified, many of which have orthologous proteins encoded within the genomes of T. gondii and N. caninum. © 2012 .

  12. The rhoptry proteome of Eimeria tenella sporozoites

    KAUST Repository

    Oakes, Richard D.

    2013-02-01

    Proteins derived from the rhoptry secretory organelles are crucial for the invasion and survival of apicomplexan parasites within host cells. The rhoptries are club-shaped organelles that contain two distinct subpopulations of proteins that localise to separate compartments of the organelle. Proteins from the neck region (rhoptry neck proteins, RON) are secreted early in invasion and a subset of these is critical for the formation and function of the moving junction between parasite and host membranes. Proteins from the bulb compartment (rhoptry protein, ROP) are released later, into the nascent parasitophorous vacuole where they have a role in modifying the vacuolar environment, and into the host cell where they act as key determinants of virulence through their ability to interact with host cell signalling pathways, causing an array of downstream effects. In this paper we present the results of an extensive proteomics analysis of the rhoptry organelles from the coccidian parasite, Eimeria tenella, which is a highly pathogenic parasite of the domestic chicken causing severe caecal coccidiosis. Several different classes of rhoptry protein have been identified. First are the RON proteins that have varying degrees of similarity to proteins of Toxoplasma gondii and Neospora caninum. For some RON families, E. tenella expresses more than one gene product and many of the individual RON proteins are differentially expressed between the sporozoite and merozoite developmental stages. The E. tenella sporozoite rhoptry expresses only a limited repertoire of proteins with homology to known ROP proteins from other coccidia, including just two secreted ROP kinases, both of which appear to be equipped for catalytic activity. Finally, a large number of hitherto undescribed proteins that map to the sporozoite rhoptry are identified, many of which have orthologous proteins encoded within the genomes of T. gondii and N. caninum. © 2012 .

  13. Immunogenic Eimeria tenella glycosylphosphatidylinositol-anchored surface antigens (SAGs induce inflammatory responses in avian macrophages.

    Directory of Open Access Journals (Sweden)

    Yock-Ping Chow

    Full Text Available At least 19 glycosylphosphatidylinositol (GPI-anchored surface antigens (SAGs are expressed specifically by second-generation merozoites of Eimeria tenella, but the ability of these proteins to stimulate immune responses in the chicken is unknown.Ten SAGs, belonging to two previously defined multigene families (A and B, were expressed as soluble recombinant (r fusion proteins in E. coli. Chicken macrophages were treated with purified rSAGs and changes in macrophage nitrite production, and in mRNA expression profiles of inducible nitric oxide synthase (iNOS and of a panel of cytokines were measured. Treatment with rSAGs 4, 5, and 12 induced high levels of macrophage nitric oxide production and IL-1β mRNA transcription that may contribute to the inflammatory response observed during E. tenella infection. Concomitantly, treatment with rSAGs 4, 5 and 12 suppressed the expression of IL-12 and IFN-γ and elevated that of IL-10, suggesting that during infection these molecules may specifically impair the development of cellular mediated immunity.In summary, some E. tenella SAGs appear to differentially modulate chicken innate and humoral immune responses and those derived from multigene family A (especially rSAG 12 may be more strongly linked with E. tenella pathogenicity associated with the endogenous second generation stages.

  14. Attenuation of LPS-induced inflammation by ICT, a derivate of icariin, via inhibition of the CD14/TLR4 signaling pathway in human monocytes.

    Science.gov (United States)

    Wu, Jinfeng; Zhou, Junmin; Chen, Xianghong; Fortenbery, Nicole; Eksioglu, Erika A; Wei, Sheng; Dong, Jingcheng

    2012-01-01

    To evaluate the anti-inflammatory potential of ICT in LPS stimulated human innate immune cells. 3, 5, 7-Trihydroxy-4'-methoxy-8-(3-hydroxy-3- methylbutyl)-flavone (ICT) is a novel derivative of icariin, the major active ingredient of Herba Epimedii, an herb used in traditional Chinese medicine. We previously demonstrated its anti-inflammatory potential in a murine macrophage cell line as well as in mouse models. We measured TNF-α production by ELISA, TLR4/CD14 expression by flow cytometry, and NF-κB and MAPK activation by western blot all in LPS-stimulated PBMC, human monocytes, or THP-1 cells after treatment with ICT. ICT inhibited LPS-induced TNF-α production in THP-1 cells, PBMCs and human monocytes in a dose-dependent manner. ICT treatment resulted in down-regulation of the expression of CD14/TLR4 and attenuated NF-κB and MAPK activation induced by LPS. We illustrate the anti-inflammatory property of ICT in human immune cells, especially in monocytes. These effects were mediated, at least partially, via inhibition of the CD14/TLR4 signaling pathway. Copyright © 2011 Elsevier B.V. All rights reserved.

  15. Evaluation of the antigenicity and immunogenicity of Eimeria tenella ...

    African Journals Online (AJOL)

    Background: The development of vaccine to control coccidiosis caused by Eimeria tenella (E. tenella) in chickens is intensifying because of the increasing threat of drug resistance to anticoccidial agents. It is important, therefore, to develop a reliable standard method for the assessment of vaccine afficacy particularly ...

  16. Inhibition of TLR2 signaling by small molecule inhibitors targeting a pocket within the TLR2 TIR domain

    Science.gov (United States)

    Mistry, Pragnesh; Laird, Michelle H. W.; Schwarz, Ryan S.; Greene, Shannon; Dyson, Tristan; Snyder, Greg A.; Xiao, Tsan Sam; Chauhan, Jay; Fletcher, Steven; Toshchakov, Vladimir Y.; MacKerell, Alexander D.; Vogel, Stefanie N.

    2015-01-01

    Toll-like receptor (TLR) signaling is initiated by dimerization of intracellular Toll/IL-1 receptor resistance (TIR) domains. For all TLRs except TLR3, recruitment of the adapter, myeloid differentiation primary response gene 88 (MyD88), to TLR TIR domains results in downstream signaling culminating in proinflammatory cytokine production. Therefore, blocking TLR TIR dimerization may ameliorate TLR2-mediated hyperinflammatory states. The BB loop within the TLR TIR domain is critical for mediating certain protein–protein interactions. Examination of the human TLR2 TIR domain crystal structure revealed a pocket adjacent to the highly conserved P681 and G682 BB loop residues. Using computer-aided drug design (CADD), we sought to identify a small molecule inhibitor(s) that would fit within this pocket and potentially disrupt TLR2 signaling. In silico screening identified 149 compounds and 20 US Food and Drug Administration-approved drugs based on their predicted ability to bind in the BB loop pocket. These compounds were screened in HEK293T-TLR2 transfectants for the ability to inhibit TLR2-mediated IL-8 mRNA. C16H15NO4 (C29) was identified as a potential TLR2 inhibitor. C29, and its derivative, ortho-vanillin (o-vanillin), inhibited TLR2/1 and TLR2/6 signaling induced by synthetic and bacterial TLR2 agonists in human HEK-TLR2 and THP-1 cells, but only TLR2/1 signaling in murine macrophages. C29 failed to inhibit signaling induced by other TLR agonists and TNF-α. Mutagenesis of BB loop pocket residues revealed an indispensable role for TLR2/1, but not TLR2/6, signaling, suggesting divergent roles. Mice treated with o-vanillin exhibited reduced TLR2-induced inflammation. Our data provide proof of principle that targeting the BB loop pocket is an effective approach for identification of TLR2 signaling inhibitors. PMID:25870276

  17. Ekstrak Sambiloto Menurunkan Patogenesitas Ookista Eimeria Tenella

    Directory of Open Access Journals (Sweden)

    Yulia Yellita

    2012-11-01

    Full Text Available Eimeria tenella is one of the nine of Eimeria species, a pathogenic intraseluler protozoa causing aviancoccidiosis. Infection was initiated by the ingestion of sporulated oocysts. The aim of this study was toinvestigate the effect of E. tenella oocyst incubation in methanol extract of Andrographis paniculata beforeinfection in broiler performance. This research used 115 broiler DOC (CP 707 devided into five groups,each group consisted of 23 broilers. The infection with 1x105 oocyst were done at the 14th day old of chicken.The 1st group was placebo (KN, while the 2nd group was infected with unincubated oocyst (KP, and theother three groups i.e. : 3rd, 4th, 5th were infected with incubated oocyst in A. paniculata extract for 2, 4, and6 hours, respectively. The number of oocysts in feces were counted on day 5th to 14th post-infection, theheterophile and macrophages were counted from caecum histology preparation, by slaughtered threechickens of each of groups on the day 0,3,6.9, and 14 post infection, and accretion body weight wasmeasured by weighing chickens per week to five-week old chickens. The results of this study indicated thatthe incubation period the sporulated oocyst in the extract of A.paniculata for six hours before infection,reduced the number of oocysts production in the feces, the number of inflammatory cells (macrophages andheterophile in the cecum, and increases body weight (gain. In conclusion A.paniculata extract decreasedthe pathogenisity of E.tenella oocyst, so the extract of A.paniculata has good potential as anticoccidia. Itis high likely that A. paniculata extract has a potential to be anticoccidia.

  18. TLR9 is required for MAPK/NF-κB activation but does not cooperate with TLR2 or TLR6 to induce host resistance to Brucella abortus.

    Science.gov (United States)

    Gomes, Marco Túlio; Campos, Priscila Carneiro; Pereira, Guilherme de Sousa; Bartholomeu, Daniella Castanheira; Splitter, Gary; Oliveira, Sergio Costa

    2016-05-01

    Brucella abortus is a Gram-negative intracellular bacterial pathogen that causes a zoonosis of worldwide occurrence, leading to undulant fever in humans and abortion in domestic animals. B. abortus is recognized by several pattern-recognition receptors triggering pathways during the host innate immune response. Therefore, here, we determined the cooperative role of TLR9 with TLR2 or TLR6 receptors in sensing Brucella Furthermore, we deciphered the host innate immune response against B. abortus or its DNA, emphasizing the role of TLR9-MAPK/NF-κB signaling pathways in the production of proinflammatory cytokines. TLR9 is required for the initial host control of B. abortus, but this TLR was dispensable after 6 wk of infection. The susceptibility of TLR9(-/-)-infected animals to Brucella paralleled with lower levels of IFN-γ produced by mouse splenocytes stimulated with this pathogen compared with wild-type cells. However, no apparent cooperative interplay was observed between TLR2-TLR9 or TLR6-TLR9 receptors to control infection. Moreover, B. abortus or its DNA induced activation of MAPK/NF-κB pathways and production of IL-12 and TNF-α by macrophages partially dependent on TLR9 but completely dependent on MyD88. In addition, B. abortus-derived CpG oligonucleotides required TLR9 to promote IL-12 and TNF-α production by macrophages. By confocal microscopy, we demonstrated that TLR9 redistributed and colocalized with lysosomal-associated membrane protein-1 upon Brucella infection. Thus, B. abortus induced TLR9 traffic, leading to cell signaling activation and IL-12 and TNF-α production. Although TLR9 recognized Brucella CpG motifs, our results suggest a new pathway of B. abortus DNA-activating macrophages independent of TLR9. © Society for Leukocyte Biology.

  19. Neuron-derived IgG protects dopaminergic neurons from insult by 6-OHDA and activates microglia through the FcγR I and TLR4 pathways.

    Science.gov (United States)

    Zhang, Jie; Niu, Na; Wang, Mingyu; McNutt, Michael A; Zhang, Donghong; Zhang, Baogang; Lu, Shijun; Liu, Yuqing; Liu, Zhihui

    2013-08-01

    Oxidative and immune attacks from the environment or microglia have been implicated in the loss of dopaminergic neurons of Parkinson's disease. The role of IgG which is an important immunologic molecule in the process of Parkinson's disease has been unclear. Evidence suggests that IgG can be produced by neurons in addition to its traditionally recognized source B lymphocytes, but its function in neurons is poorly understood. In this study, extensive expression of neuron-derived IgG was demonstrated in dopaminergic neurons of human and rat mesencephalon. With an in vitro Parkinson's disease model, we found that neuron-derived IgG can improve the survival and reduce apoptosis of dopaminergic neurons induced by 6-hydroxydopamine toxicity, and also depress the release of NO from microglia triggered by 6-hydroxydopamine. Expression of TNF-α and IL-10 in microglia was elevated to protective levels by neuron-derived IgG at a physiologic level via the FcγR I and TLR4 pathways and microglial activation could be attenuated by IgG blocking. All these data suggested that neuron-derived IgG may exert a self-protective function by activating microglia properly, and IgG may be involved in maintaining immunity homeostasis in the central nervous system and serve as an active factor under pathological conditions such as Parkinson's disease. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  20. Coagulin-L ameliorates TLR4 induced oxidative damage and immune response by regulating mitochondria and NOX-derived ROS

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Sukka Santosh [Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Chauhan, Parul [Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Maurya, Preeti [Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Academy of Scientific and Innovative Research, New Delhi 110025 (India); Saini, Deepika [Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Yadav, Prem Prakash, E-mail: pp_yadav@cdri.res.in [Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India); Barthwal, Manoj Kumar, E-mail: manojbarthwal@cdri.res.in [Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow 226031 (India)

    2016-10-15

    Withanolides possess diverse biological and pharmacological activity but their immunomodulatory function is less realized. Hence, coagulin-L, a withanolide isolated from Withania coagulans Dunal has been studied for such an effect in human and murine cells, and mice model. Coagulin-L (1, 3, 10 μM) exhibited immunomodulatory effect by suppressing TLR4 induced immune mediators such as cytokines (GMCSF, IFNα, IFNγ, IL-1α, IL-1Rα, IL-1β, IL-2, IL-2R, IL-4, IL-5, IL-6, IL-7, IL-10, IL-12 (p40/p70), IL-13, IL-15, IL-17), chemokines (IL-8/CXCL8, MIG/CXCL9, IP-10/CXCL10, KC, MCP-1/CCL2, MIP-1α/CCL3, MIP-1β/CCL4, RANTES/CCL5, eotaxin/CCL11), growth factors (FGF-basic, VEGF), nitric oxide and intracellular superoxide. Mechanistically, coagulin-L abrogated LPS induced total and mitochondrial ROS generation, NOX2, NOX4 mRNA expression, IRAK and MAPK (p38, JNK, ERK) activation. Coagulin-L also attenuated IκBα degradation, which prevented NFκB downstream iNOS expression and pro-inflammatory cytokine release. Furthermore, coagulin-L (10, 25, 50 mg/kg, p.o.), undermined the LPS (10 mg/kg, i.p.) induced endotoxemia response in mice as evinced from diminished cytokine release, nitric oxide, aortic p38 MAPK activation and endothelial tissue impairment besides suppressing NOX2 and NOX4 expression in liver and aorta. Moreover, coagulin-L also alleviated the ROS mediated oxidative damage which was assessed through protein carbonyl, lipid hydroperoxide, 8-isoprostane and 8-hydroxy-2-deoxyguanosine quantification. To extend, coagulin-L also suppressed carrageenan-induced paw edema and thioglycollate-induced peritonitis in mice. Therefore, coagulin-L can be of therapeutic importance in pathological conditions induced by oxidative damage. - Highlights: • Coagulin-L demonstrates immunomodulatory effects in vivo and in vitro by modulating ROS. • Coagulin-L modulates TH1/TH2/TH17 immunokines. • Coagulin-L exerts immunomodulatory effect by regulating TLR4-IRAK- ROS

  1. Immunomodulatory properties of Alternanthera tenella Colla aqueous extracts in mice

    Directory of Open Access Journals (Sweden)

    R.N.M. Guerra

    2003-09-01

    Full Text Available Plants from the genus Alternanthera are thought to possess antimicrobial and antiviral properties. In Brazilian folk medicine, the aqueous extract of A. tenella Colla is used for its anti-inflammatory activity. The present study investigated the immunomodulatory property of A. tenella extract by evaluating the antibody production in male albino Swiss mice weighing 20-25 g (10 per group. The animals received standard laboratory diet and water ad libitum. The effect of A. tenella extract (5 and 50 mg/kg, ip was evaluated in mice immunized with sheep red blood cells (SRBC 10%, ip as T-dependent antigen, or in mice stimulated with mitogens (10 µg, Escherichia coli lipopolysaccharide, LPS, ip. The same doses (5 and 50 mg/kg, ip of A. tenella extract were also tested for antitumor activity, using the Ehrlich ascites carcinoma as model. The results showed that 50 mg/kg A. tenella extract ip significantly enhanced IgM (64% and IgG2a (50% antibody production in mice treated with LPS mitogen. The same dose had no effect on IgM-specific response, whereas the 5 mg/kg treatment caused a statiscally significant reduction of anti-SRBC IgM-specific antibodies (82%. The aqueous extract of A. tenella (50 mg/kg increased the life span (from 16 ± 1 to 25 ± 1 days and decreased the number of viable tumor cells (59% in mice with Ehrlich ascites carcinoma. The present findings are significant for the development of alternative, inexpensive and perhaps even safer strategies for cancer treatment.

  2. Association of TLR1, TLR2, TLR4, TLR6, and TIRAP polymorphisms with disease susceptibility.

    Science.gov (United States)

    Noreen, Mamoona; Arshad, Muhammad

    2015-06-01

    Toll like receptors (TLRs) play a crucial role in regulation of innate as well as adaptive immunity. TLRs recognize a distinct but limited repertoire of conserved microbial products. Ligand binding to TLRs activates the signaling cascade and results in activation of multiple inflammatory genes. Variation in this immune response is under genetic control. Polymorphisms in genes associated with inflammatory pathway especially influence the outcome of diseases. TLR2 makes heterodimer with TLR1 or TLR6 and recognizes a wide variety of microbial ligands. In this review, we summarize studies of polymorphisms in genes encoding TLR1, TLR2, TLR4, TLR6, and most polymorphic adaptor protein, Mal/TIRAP, revealing their effect on susceptibility to diseases.

  3. Microglia Induce Neurotoxic IL-17+ γδ T Cells Dependent on TLR2, TLR4, and TLR9 Activation.

    Directory of Open Access Journals (Sweden)

    Katja Derkow

    Full Text Available Interleukin-17 (IL-17 acts as a key regulator in central nervous system (CNS inflammation. γδ T cells are an important innate source of IL-17. Both IL-17+ γδ T cells and microglia, the major resident immune cells of the brain, are involved in various CNS disorders such as multiple sclerosis and stroke. Also, activation of Toll-like receptor (TLR signaling pathways contributes to CNS damage. However, the mechanisms underlying the regulation and interaction of these cellular and molecular components remain unclear.In this study, we investigated the crosstalk between γδ T cells and microglia activated by TLRs in the context of neuronal damage. To this end, co-cultures of IL-17+ γδ T cells, neurons, and microglia were analyzed by immunocytochemistry, flow cytometry, ELISA and multiplex immunoassays.We report here that IL-17+ γδ T cells but not naïve γδ T cells induce a dose- and time-dependent decrease of neuronal viability in vitro. While direct stimulation of γδ T cells with various TLR ligands did not result in up-regulation of CD69, CD25, or in IL-17 secretion, supernatants of microglia stimulated by ligands specific for TLR2, TLR4, TLR7, or TLR9 induced activation of γδ T cells through IL-1β and IL-23, as indicated by up-regulation of CD69 and CD25 and by secretion of vast amounts of IL-17. This effect was dependent on the TLR adaptor myeloid differentiation primary response gene 88 (MyD88 expressed by both γδ T cells and microglia, but did not require the expression of TLRs by γδ T cells. Similarly to cytokine-primed IL-17+ γδ T cells, IL-17+ γδ T cells induced by supernatants derived from TLR-activated microglia also caused neurotoxicity in vitro. While these neurotoxic effects required stimulation of TLR2, TLR4, or TLR9 in microglia, neuronal injury mediated by bone marrow-derived macrophages did not require TLR signaling. Neurotoxicity mediated by IL-17+ γδ T cells required a direct cell-cell contact between T

  4. Distinct dictation of Japanese encephalitis virus-induced neuroinflammation and lethality via triggering TLR3 and TLR4 signal pathways.

    Directory of Open Access Journals (Sweden)

    Young Woo Han

    2014-09-01

    Full Text Available Japanese encephalitis (JE is major emerging neurologic disease caused by JE virus. To date, the impact of TLR molecules on JE progression has not been addressed. Here, we determined whether each TLR modulates JE, using several TLR-deficient mouse strains (TLR2, TLR3, TLR4, TLR7, TLR9. Surprisingly, among the tested TLR-deficient mice there were contrasting results in TLR3(-/- and TLR4(-/- mice, i.e. TLR3(-/- mice were highly susceptible to JE, whereas TLR4(-/- mice showed enhanced resistance to JE. TLR3 ablation induced severe CNS inflammation characterized by early infiltration of inflammatory CD11b(+Ly-6Chigh monocytes along with profoundly increased viral burden, proinflammatory cytokine/chemokine expression as well as BBB permeability. In contrast, TLR4(-/- mice showed mild CNS inflammation manifested by reduced viral burden, leukocyte infiltration and proinflammatory cytokine expression. Interestingly, TLR4 ablation provided potent in vivo systemic type I IFN innate response, as well as ex vivo type I IFN production associated with strong induction of antiviral PRRs (RIG-I, MDA5, transcription factors (IRF-3, IRF-7, and IFN-dependent (PKR, Oas1, Mx and independent ISGs (ISG49, ISG54, ISG56 by alternative activation of IRF3 and NF-κB in myeloid-derived DCs and macrophages, as compared to TLR3(-/- myeloid-derived cells which were more permissive to viral replication through impaired type I IFN innate response. TLR4 ablation also appeared to mount an enhanced type I IFN innate and humoral, CD4(+ and CD8(+ T cell responses, which were mediated by altered immune cell populations (increased number of plasmacytoid DCs and NK cells, reduced CD11b(+Ly-6C(high monocytes and CD4(+Foxp3(+ Treg number in lymphoid tissue. Thus, potent type I IFN innate and adaptive immune responses in the absence of TLR4 were closely coupled with reduced JE lethality. Collectively, these results suggest that a balanced triggering of TLR signal array by viral components

  5. TLR9 ligation in pancreatic stellate cells promotes tumorigenesis.

    Science.gov (United States)

    Zambirinis, Constantinos P; Levie, Elliot; Nguy, Susanna; Avanzi, Antonina; Barilla, Rocky; Xu, Yijie; Seifert, Lena; Daley, Donnele; Greco, Stephanie H; Deutsch, Michael; Jonnadula, Saikiran; Torres-Hernandez, Alejandro; Tippens, Daniel; Pushalkar, Smruti; Eisenthal, Andrew; Saxena, Deepak; Ahn, Jiyoung; Hajdu, Cristina; Engle, Dannielle D; Tuveson, David; Miller, George

    2015-11-16

    Modulation of Toll-like receptor (TLR) signaling can have protective or protumorigenic effects on oncogenesis depending on the cancer subtype and on specific inflammatory elements within the tumor milieu. We found that TLR9 is widely expressed early during the course of pancreatic transformation and that TLR9 ligands are ubiquitous within the tumor microenvironment. TLR9 ligation markedly accelerates oncogenesis, whereas TLR9 deletion is protective. We show that TLR9 activation has distinct effects on the epithelial, inflammatory, and fibrogenic cellular subsets in pancreatic carcinoma and plays a central role in cross talk between these compartments. Specifically, TLR9 activation can induce proinflammatory signaling in transformed epithelial cells, but does not elicit oncogene expression or cancer cell proliferation. Conversely, TLR9 ligation induces pancreatic stellate cells (PSCs) to become fibrogenic and secrete chemokines that promote epithelial cell proliferation. TLR9-activated PSCs mediate their protumorigenic effects on the epithelial compartment via CCL11. Additionally, TLR9 has immune-suppressive effects in the tumor microenvironment (TME) via induction of regulatory T cell recruitment and myeloid-derived suppressor cell proliferation. Collectively, our work shows that TLR9 has protumorigenic effects in pancreatic carcinoma which are distinct from its influence in extrapancreatic malignancies and from the mechanistic effects of other TLRs on pancreatic oncogenesis. © 2015 Zambirinis et al.

  6. Identification and characterization of secreted proteins in Eimeria tenella

    Science.gov (United States)

    Ramlee, Intan Azlinda; Firdaus-Raih, Mohd; Wan, Kiew-Lian

    2015-09-01

    Eimeria tenella is a protozoan parasite that causes coccidiosis, an economically important disease in the poultry industry. The characterization of proteins that are secreted by parasites have been shown to play important roles in parasite invasion and are considered to be potential control agents. In this study, 775 proteins potentially secreted by E. tenella were identified. These proteins were further filtered to remove mitochondrial proteins. Out of 763 putative secreted proteins, 259 proteins possess transmembrane domains while another 150 proteins have GPI (Glycosylphosphatidylinositol) anchors. Homology search revealed that 315 and 448 proteins have matches with known and hypothetical proteins in the database, respectively. Within this data set, previously characterized secretory proteins such as micronemes, rhoptry kinases and dense granules were detected.

  7. Activated human neonatal CD8+ T cells are subject to immunomodulation by direct TLR2 or TLR5 stimulation.

    LENUS (Irish Health Repository)

    McCarron, Mark

    2012-02-01

    In conditions of optimal priming, the neonate possesses competency to mount quantitatively adult-like responses. Vaccine formulations containing sufficiently potent adjuvants may overcome the neonate\\'s natural tendency for immunosuppression and provoke a similarly robust immune response. TLR expression on T cells represents the possibility of directly enhancing T cell immunity. We examined the ex vivo responsiveness of highly purified human cord blood-derived CD8(+) T cells to direct TLR ligation by a repertoire of TLR agonists. In concert with TCR stimulation, only Pam(3)Cys (palmitoyl-3-Cys-Ser-(Lys)(4)) and flagellin monomers significantly enhanced proliferation, CD25(+) expression, IL-2, IFN-gamma, TNF-alpha, and intracellular granzyme B expression. TLR2 and TLR5 mRNA was detected in the CD8(+) T cells. Blocking studies confirmed that the increase in IFN-gamma production was by the direct triggering of surface TLR2 or TLR5. The simultaneous exposure of CD8(+) T cells to both TLR agonists had an additive effect on IFN-gamma production. These data suggest that a combination of the two TLR ligands would be a potent T cell adjuvant. This may represent a new approach to TLR agonist-based adjuvant design for future human neonatal vaccination strategies requiring a CD8(+) component.

  8. Immunoproteomic analysis of proteins from unsporulated Oocysts of Eimeria tenella in MALDI TOF/TOF tandem mass spectrometry

    Science.gov (United States)

    Immunoproteomic approaches were conducted to identify antigenic proteins from the total proteins of unsporulated oocysts of Eimeria tenella (E. tenella). Approximately 101 protein spots were recognized by chicken sera infected experimentally with E. tenella. Fourty-six spots of unsporulated oocysts ...

  9. Vaccination with Eimeria tenella elongation factor-1α recombinant protein induces protective immunity against E. tenella and E. maxima infections.

    Science.gov (United States)

    Lin, Rui-Qing; Lillehoj, Hyun S; Lee, Seung Kyoo; Oh, Sungtaek; Panebra, Alfredo; Lillehoj, Erik P

    2017-08-30

    Avian coccidiosis is caused by multiple species of the apicomplexan protozoan, Eimeria, and is one of the most economically devastating enteric diseases for the poultry industry worldwide. Host immunity to Eimeria infection, however, is relatively species-specific. The ability to immunize chickens against different species of Eimeria using a single vaccine will have a major beneficial impact on commercial poultry production. In this paper, we describe the molecular cloning, purification, and vaccination efficacy of a novel Eimeria vaccine candidate, elongation factor-1α (EF-1α). One day-old broiler chickens were given two subcutaneous immunizations one week apart with E. coli-expressed E. tenella recombinant (r)EF-1α protein and evaluated for protection against challenge infection with E. tenella or E. maxima. rEF-1α-vaccinated chickens exhibited increased body weight gains, decreased fecal oocyst output, and greater serum anti-EF-1α antibody levels following challenge infection with either E. tenella or E. maxima compared with unimmunized controls. Vaccination with EF-1α may represent a new approach to inducing cross-protective immunity against avian coccidiosis in the field. Published by Elsevier B.V.

  10. Ekstrak Sambiloto (Andrographis paniculata Menurunkan Jumlah Skizon, Mikrogamet, Makrogamet, dan Oosista Eimeria tenella (EXTRACT OF ANDROGRAPHIS PANICULATA DECREASED SCHIZONTS, MICROGAMETES, MACROGAMETES AND OOCYSTS NUMBER OF EIMERIA TENELLA

    Directory of Open Access Journals (Sweden)

    UMI CAHYANINGSIH

    2013-07-01

    Full Text Available The aim of this research was to observe the effect of ethanol extract of Andrographis paniculata givenin grading doses to the schizonts, microgamete, macrogamete, and oocytes counts of Eimeria tenella inchicken caecum. A total of ninety day old broiler chicks were used in the study. At two weeks old the broilerswere divided into six groups. Each group consisted of 15 broilers, the 6 groups were: (i negative control(broilers did not receive any treatment; (ii positive control (each animal were infected with 104 E. tenellaoocytes; (iii medicine control (each animal were infected with 104 E. tenella oocytes and coccidiostat; (ivA1 (each animal were infected with 104 E. tenella oocytes and paniculata extract 90 mg/kg body weight; (vA2 (each animal were infected with 104 E. tenella oocytes and paniculata extract 180 mg/kg body weight;and (vi A3 (each animal were infected with 104 E. tenella oocytes and paniculata extract 360 mg/kg bodyweight. At day 6, 9, 13, 16, and 22 post infection three broilers from each group were sacrificed and theirceca were collected for histopathological examination. The results showed that paniculata extract at dose90 mg/kg body weight and 180 mg/kg body weight was able to decrease the numbers of shizont, microgamete,macrogamete, and oocytes of E. tenella in the chicken caecum.

  11. Generation of anti-TLR2 intrabody mediating inhibition of macrophage surface TLR2 expression and TLR2-driven cell activation

    Directory of Open Access Journals (Sweden)

    Lindenmaier Werner

    2010-04-01

    Full Text Available Abstract Background Toll-like receptor (TLR 2 is a component of the innate immune system and senses specific pathogen associated molecular patterns (PAMPs of both microbial and viral origin. Cell activation via TLR2 and other pattern recognition receptors (PRRs contributes to sepsis pathology and chronic inflammation both relying on overamplification of an immune response. Intracellular antibodies expressed and retained inside the endoplasmatic reticulum (ER-intrabodies are applied to block translocation of secreted and cell surface molecules from the ER to the cell surface resulting in functional inhibition of the target protein. Here we describe generation and application of a functional anti-TLR2 ER intrabody (αT2ib which was generated from an antagonistic monoclonal antibody (mAb towards human and murine TLR2 (T2.5 to inhibit the function of TLR2. αT2ib is a scFv fragment comprising the variable domain of the heavy chain and the variable domain of the light chain of mAb T2.5 linked together by a synthetic (Gly4Ser3 amino acid sequence. Results Coexpression of αT2ib and mouse TLR2 in HEK293 cells led to efficient retention and accumulation of TLR2 inside the ER compartment. Co-immunoprecipitation of human TLR2 with αT2ib indicated interaction of αT2ib with its cognate antigen within cells. αT2ib inhibited NF-κB driven reporter gene activation via TLR2 but not through TLR3, TLR4, or TLR9 if coexpressed in HEK293 cells. Co-transfection of human TLR2 with increasing amounts of the expression plasmid encoding αT2ib into HEK293 cells demonstrated high efficiency of the TLR2-αT2ib interaction. The αT2ib open reading frame was integrated into an adenoviral cosmid vector for production of recombinant adenovirus (AdV-αT2ib. Transduction with AdVαT2ib specifically inhibited TLR2 surface expression of murine RAW264.7 and primary macrophages derived from bone marrow (BMM. Furthermore, TLR2 activation dependent TNFα mRNA accumulation, as well

  12. Generation of anti-TLR2 intrabody mediating inhibition of macrophage surface TLR2 expression and TLR2-driven cell activation.

    Science.gov (United States)

    Kirschning, Carsten J; Dreher, Stefan; Maass, Björn; Fichte, Sylvia; Schade, Jutta; Köster, Mario; Noack, Andreas; Lindenmaier, Werner; Wagner, Hermann; Böldicke, Thomas

    2010-04-13

    Toll-like receptor (TLR) 2 is a component of the innate immune system and senses specific pathogen associated molecular patterns (PAMPs) of both microbial and viral origin. Cell activation via TLR2 and other pattern recognition receptors (PRRs) contributes to sepsis pathology and chronic inflammation both relying on overamplification of an immune response. Intracellular antibodies expressed and retained inside the endoplasmatic reticulum (ER-intrabodies) are applied to block translocation of secreted and cell surface molecules from the ER to the cell surface resulting in functional inhibition of the target protein. Here we describe generation and application of a functional anti-TLR2 ER intrabody (alphaT2ib) which was generated from an antagonistic monoclonal antibody (mAb) towards human and murine TLR2 (T2.5) to inhibit the function of TLR2. alphaT2ib is a scFv fragment comprising the variable domain of the heavy chain and the variable domain of the light chain of mAb T2.5 linked together by a synthetic (Gly4Ser)3 amino acid sequence. Coexpression of alphaT2ib and mouse TLR2 in HEK293 cells led to efficient retention and accumulation of TLR2 inside the ER compartment. Co-immunoprecipitation of human TLR2 with alphaT2ib indicated interaction of alphaT2ib with its cognate antigen within cells. alphaT2ib inhibited NF-kappaB driven reporter gene activation via TLR2 but not through TLR3, TLR4, or TLR9 if coexpressed in HEK293 cells. Co-transfection of human TLR2 with increasing amounts of the expression plasmid encoding alphaT2ib into HEK293 cells demonstrated high efficiency of the TLR2-alphaT2ib interaction. The alphaT2ib open reading frame was integrated into an adenoviral cosmid vector for production of recombinant adenovirus (AdV)-alphaT2ib. Transduction with AdValphaT2ib specifically inhibited TLR2 surface expression of murine RAW264.7 and primary macrophages derived from bone marrow (BMM). Furthermore, TLR2 activation dependent TNFalpha mRNA accumulation, as

  13. Dioscorin isolated from Dioscorea alata activates TLR4-signaling pathways and induces cytokine expression in macrophages.

    Science.gov (United States)

    Fu, Shu-Ling; Hsu, Ya-Hui; Lee, Pei-Yeh; Hou, Wen-Chi; Hung, Ling-Chien; Lin, Chao-Hsiung; Chen, Chiu-Ming; Huang, Yu-Jing

    2006-01-06

    The Toll-like receptor 4 (TLR4)-signaling pathway is crucial for activating both innate and adaptive immunity. TLR4 is a promising molecular target for immune-modulating drugs, and TLR4 agonists are of therapeutic potential for treating immune diseases and cancers. Several medicinal herb-derived components have recently been reported to act via TLR4-dependent pathways, suggesting that medicinal plants are potential resources for identifying TLR4 activators. We have applied a screening procedure to systematically identify herbal constituents that activate TLR4. To exclude possible LPS contamination in these plant-derived components, a LPS inhibitor, polymyxin B, was added during screening. One of the plant components we identified from the screening was dioscorin, the glycoprotein isolated from Dioscorea alata. It induced TLR4-downstream cytokine expression in bone marrow cells isolated from TLR4-functional C3H/HeN mice but not from TLR4-defective C3H/HeJ mice. Dioscorin also stimulated multiple signaling molecules (NF-kappaB, ERK, JNK, and p38) and induced the expression of cytokines (TNF-alpha, IL-1beta, and IL-6) in murine RAW 264.7 macrophages. Furthermore, the ERK, p38, JNK, and NF-kappaB-mediated pathways are all involved in dioscorin-mediated TNF-alpha production. In summary, our results demonstrate that dioscorin is a novel TLR4 activator and induces macrophage activation via typical TLR4-signaling pathways.

  14. The effects of Ostertagia occidentalis somatic antigens on ovine TLR2 and TLR4 expression

    Directory of Open Access Journals (Sweden)

    Hassan BORJI

    2015-10-01

    Full Text Available Background: Recognition of helminth-derived pathogen associated molecular patterns (PAMPs by pattern recognition receptors (PRRs, including toll like recep­tors (TLRs is the first step towards initiating anti–helminth immune re­sponses.Methods: Using somatic antigens of Ostertagia occidentalis, an important abomasal parasite of ruminants, the expression of ovine TLR2 and TLR4 in peripheral blood mononuclear cells (PBMCs was analyzed by real-time quatitative reverse-transcrip­tion polymerase chain reaction (qRT-PCR. Somatic antigens of O. occidentalis were prepared to stimulate ovine PBMCs in a time and dose dependent manner.Results: A high expression of TLR2 and TLR4 was observed in PBMCs cultured with somatic antigens of the parasites specially when PBMCs were cultured with 100 µg/ml of somatic antigens and incubated for 2h. Up-regulation of TLR2 expres­sion was more pronounced and evident in our study.Conclsusion: Somatic antigens of O. occidentalis have immunostimulatory and domi­nant role on peripheral immune cells. This study provide for the first time evidence of induction of TLRs in ovine PBMCs by somatic antigen of O. occidentalis

  15. Eimeria tenella: in vitro development in irradiated bovine kidney cells

    Energy Technology Data Exchange (ETDEWEB)

    Crane, M.St.J.; Schmatz, D.M.; Stevens, S.; Habbersett, M.C.; Murray, P.K. (Merck Sharp and Dohme Research Labs., Rahway, NJ (USA))

    1984-06-01

    The initial infection and first-generation development of Eimeria tenella was quantified using a cloned MDBK (Madin-Darby Bovine Kidney) cell line, irradiated with gamma radiation prior to infection, as the host cell. Irradiated cell cultures were found to be more susceptible to infection and had a greater capacity to support parasite development than non-irradiated cultures. It was suggested that the larger proportion of cells in the G/sub 2/ phase of the cell cycle, the larger individual cell size and the inhibition of cell division in the irradiated cultures were all factors contributing to the increased susceptibility to infection and capacity to support parasite growth and development. The application of this technique (host cell irradiation) to the cultivation of other intracellular, protozoan parasites is discussed.

  16. Eimeria tenella: in vitro development in irradiated bovine kidney cells

    International Nuclear Information System (INIS)

    Crane, M. St.J.; Schmatz, D.M.; Stevens, S.; Habbersett, M.C.; Murray, P.K.

    1984-01-01

    The initial infection and first-generation development of Eimeria tenella was quantified using a cloned MDBK (Madin-Darby Bovine Kidney) cell line, irradiated with gamma radiation prior to infection, as the host cell. Irradiated cell cultures were found to be more susceptible to infection and had a greater capacity to support parasite development than non-irradiated cultures. It was suggested that the larger proportion of cells in the G 2 phase of the cell cycle, the larger individual cell size and the inhibition of cell division in the irradiated cultures were all factors contributing to the increased susceptibility to infection and capacity to support parasite growth and development. The application of this technique (host cell irradiation) to the cultivation of other intracellular, protozoan parasites is discussed. (author)

  17. Attenuate Eimeria Tenella parasite by gamma radiation in chicken vaccination

    International Nuclear Information System (INIS)

    El-atar, M.A.

    1998-01-01

    Mature occysts of eimeria tenella were attenuated by different doses of gamma radiation. The vitality, pathogenicity and immunogenicity of these occysts were examined by infecting one day old broiler chicks. The study revealed that the irradiated occysts lost pathogenicity by increasing radiation dose. To examine the immunogenicity of irradiated occysts, chickens were challenged 28 days post immunogenic infection. It was shown that the irradiated occycts kept their immunogenicity but this ability decreased when the irradiation dose was increased. Also, the number of vaccination doses as well as the level of irradiation were studied. Occysts irradiated with 15, 18, 20 Krad were used to vaccinate one-day old broiler chicks for one or two times, and seven-day old chicks for three times. High level of protection was observed as shown by disappeaeance of clinical signs or mortality in most vaccinated groups

  18. Differing susceptibilities of Eimeria acervulina, Eimeria maxima, and Eimeria tenella oocysts to desiccation.

    Science.gov (United States)

    Jenkins, Mark C; Parker, Carolyn; O'Brien, Celia; Miska, Katarzyna; Fetterer, Raymond

    2013-10-01

    Outbreaks of avian coccidiosis may occur when susceptible chickens are raised on litter containing viable Eimeria oocysts. The purpose of this study was to compare the relative sensitivities of Eimeria acervulina, Eimeria maxima, and Eimeria tenella oocysts to dessication. Sporulated E. acervulina, E. maxima, or E. tenella oocysts were incorporated into gelatin beads and incubated at 32 C for 0, 1, 2, or 3 days. In vitro oocyst excystation rates were measured for each combination of Eimeria species and incubation time. Day-old broiler chicks were allowed to ingest the oocysts-containing beads, and total oocyst production was measured from days 5-8 post-inoculation. Although no effect on excystation was observed, E. maxima oocysts displayed greater resistance to drying compared to E. acervulina and E. tenella oocysts. Eimeria acervulina oocyst production decreased 100-fold after 1-2 days incubation. Eimeria tenella oocysts were slightly more resistant to drying in that a 100-fold decrease in oocyst production was delayed until 2 days. For both E. acervulina and E. tenella , very few oocysts were observed after 3 days incubation. Eimeria maxima oocyst production remained high at all time points. Subsequent studies revealed E. maxima oocyst production was ablated only after 5 days incubation. These findings may explain in part the observed prevalence of E. maxima in litter from commercial poultry operations.

  19. Effects of artemisinin in broiler chickens challenged with Eimeria acervulina, E. maxima and E. tenella in battery trials.

    Science.gov (United States)

    Pop, Loredana; Györke, Adriana; Tǎbǎran, Alexandru Flaviu; Dumitrache, Mirabela Oana; Kalmár, Zsuzsa; Magdaş, Cristian; Mircean, Viorica; Zagon, Diana; Balea, Anamaria; Cozma, Vasile

    2015-12-15

    Four experiments were conceived in order to test the efficacy of artemisinin, a sesquiterpene lactone derived from Artemisia annua, in single experimental infection of broiler chickens with Eimeria acervulina (1 × 10(5) oocysts), Eimeria maxima (5 × 10(4) oocysts) or Eimeria tenella (1 × 10(4) oocysts), and mixed infection with all 3 species (3.2 × 10(4) Eimeria spp. oocysts). For each experiment, three different dosages of artemisinin (5, 50 and 500 ppm) were compared with a negative control (uninfected, unmedicated), a positive control (infected, unmedicated) and a classical anticoccidial (monensin). The weight gain (WG), feed conversion ratio (FCR), oocysts shedded per gram of feces (OPG), lesion score, oocysts sporulation rates and mortality rate were recorded in all groups. The dosage of 5 ppm of artemisinin improved the WG and FCR for the chickens infected with E. acervulina. The OPG was significantly decreased in all the groups medicated with artemisinin and challenged with a mixed infection (p ≤ 0.01). The lesion score of the chickens challenged with Eimeria was reduced by different concentrations of artemisinin, depending on the species involved, but this compound did not have a positive effect on the lesions caused by E. acervulina. Histopathological analysis revealed superficial erosions of the intestinal mucosa, mixt. mononuclear and heterophilic inflammatory infiltrate in the lamina propria and intralesional presence of various developmental stages of parasite in groups infected with Eimeria spp.The sporulation rate of E. acervulina and E. maxima oocysts was significantly affected by 500 ppm of artemisinin, whilst the dosage of 5 ppm affected the sporulation of E. tenella oocysts. These data suggest that artemisinin is not effective against single eimerian infections but could be used as an alternative in mixed coccidiosis, especially if its effect on the oocysts sporulation would be fully investigated. Copyright © 2015 Elsevier B.V. All rights

  20. Molecular Characterization and Immune Protection of a New Conserved Hypothetical Protein of Eimeria tenella.

    Directory of Open Access Journals (Sweden)

    Qi Zhai

    Full Text Available The genome sequences of Eimeria tenella have been sequenced, but >70% of these genes are currently categorized as having an unknown function or annotated as conserved hypothetical proteins, and few of them have been studied. In the present study, a conserved hypothetical protein gene of E. tenella, designated EtCHP559, was cloned using rapid amplification of cDNA 5'-ends (5'RACE based on the expressed sequence tag (EST. The 1746-bp full-length cDNA of EtCHP559 contained a 1224-bp open reading frame (ORF that encoded a 407-amino acid polypeptide with the predicted molecular weight of 46.04 kDa. Real-time quantitative PCR analysis revealed that EtCHP559 was expressed at higher levels in sporozoites than in the other developmental stages (unsporulated oocysts, sporulated oocysts and second generation merozoites. The ORF was inserted into pCold-TF to produce recombinant EtCHP559. Using western blotting, the recombinant protein was successfully recognized by rabbit serum against E. tenella sporozoites. Immunolocalization by using EtCHP559 antibody showed that EtCHP559 was mainly distributed on the parasite surface in free sporozoites and became concentrated in the anterior region after sporozoites were incubated in complete medium. The EtCHP559 became uniformly dispersed in immature and mature schizonts. Inhibition of EtCHP559 function using anti-rEtCHP559 polyclonal antibody reduced the ability of E. tenella sporozoites to invade host cells by >70%. Animal challenge experiments demonstrated that the recombinant EtCHP559 significantly increased the average body weight gain, reduced the oocyst outputs, alleviated cecal lesions of the infected chickens, and resulted in anticoccidial index >160 against E. tenella. These results suggest that EtCHP559 plays an important role in sporozoite invasion and could be an effective candidate for the development of a new vaccine against E. tenella.

  1. Effect of dietary vitamin E on Eimeria tenella-induced oxidative ...

    African Journals Online (AJOL)

    ramezanali

    2012-05-10

    May 10, 2012 ... Full Length Research Paper. Effect of dietary ... vitamin E (p<0.05). A significant rise of plasma and erythrocyte MDA was ... biological membranes, thereby making them stable. This prevents free ... Vegetable oil. 2.00. 2.00 ..... tenella: a review of the type strain selected for genome sequencing. Avian Pathol.

  2. Dietary Curcuma longa enhances resistance against Eimeria maxima and Eimeria tenella infections in chickens

    Science.gov (United States)

    The effects of dietary supplementation with an organic extract of Curcuma longa on systemic and local immune responses to experimental Eimeria maxima and E. tenella infections were evaluated in commercial broiler chickens. Infected chickens given the C. longa-containing diet had increased body weig...

  3. TLR4 plays a crucial role in MSC-induced inhibition of NK cell function

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ying [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Liu, Jin; Liu, Yang; Qin, Yaru [Beijing Institute of Radiation Medicine, Beijing (China); Luo, Qun [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Wang, Quanli, E-mail: 13691110351@163.com [No. 307 Hospital of the Chinese People' s Liberation Army, Beijing (China); Duan, Haifeng, E-mail: duanhf0720@163.com [Beijing Institute of Radiation Medicine, Beijing (China)

    2015-08-21

    Mesenchymal stem cells (MSC) are a kind of stromal cell within the tumor microenvironment. In our research, MSC derived from acute myeloid leukemia patients' bone marrow (AML-MSC) and lung cancer tissues (LC-MSC) as well as normal bone marrow-derived MSC (BM-MSC) cultured in conditioned medium of HeLa cells were found to have higher expressions of Toll-like receptor (TLR4) mRNA compared with BM-MSC. The sorted TLR4-positive MSC (TLR4+ MSC) differed in cytokine (interleukin-6, interleukin-8, and monocyte chemoattractant protein-1) secretion from those of unsorted MSC. MSC was reported to inhibit natural killer (NK) cell proliferation and function. In this research, we confirmed that TLR4+ MSC aggravate this suppression. Furthermore, when TLR4 in the sorted cells were stimulated by LPS or following blocked by antibody, the suppression on NK cell proliferation and cytotoxicity were more intensive or recovered respectively. Compared to unsorted MSC, NKG2D receptor expression on NK cells were also inhibited by TLR4+ MSC. These findings suggest that activation of TLR4 pathway is important for TLR4+ MSC and MSC to obstruct anti-tumor immunity by inhibiting NK cell function, which may provide a potential stroma-targeted tumor therapy. - Highlights: • TLR4+ MSC inhibit NK cell proliferation in vivo and in vitro. • TLR4+ MSC inhibit NKG2D expression on NK cells and NK cell cytotoxicity. • The distinguished cytokine expression of TLR4+ MSC may contribute to the inhibition on NK cell function.

  4. Immunoproteomic analysis of the protein repertoire of unsporulated Eimeria tenella oocysts

    Directory of Open Access Journals (Sweden)

    Zhang Zhenchao

    2017-01-01

    Full Text Available The apicomplexan protozoans Eimeria spp. cause coccidioses, the most common intestinal diseases in chickens. Coccidiosis is associated with significant animal welfare issues and has a high economic impact on the poultry industry. Lack of a full understanding of immunogenic molecules and their precise functions involved in the Eimeria life cycles may limit development of effective vaccines and drug therapies. In this study, immunoproteomic approaches were used to define the antigenic protein repertoire from the total proteins of unsporulated Eimeria tenella oocysts. Approximately 101 protein spots were recognized in sera from chickens infected experimentally with E. tenella. Forty-six spots of unsporulated oocysts were excised from preparative gels and identified by matrix-assisted laser desorption ionization time-of-flight MS (MALDI-TOF-MS and MALDI-TOF/TOF-MS. For unsporulated oocysts, 13 known proteins of E. tenella and 17 homologous proteins to other apicomplexan or protozoan parasites were identified using the ‘Mascot’ server. The remaining proteins were searched against the E. tenella protein sequence database using the ‘Mascot in-house’ search engine (version 2.1 in automated mode, and 12 unknown proteins were identified. The amino acid sequences of the unknown proteins were searched using BLAST against non-redundant sequence databases (NCBI, and 9 homologous proteins in unsporulated oocyst were found homologous to proteins of other apicomplexan parasites. These findings may provide useful evidence for understanding parasite biology, pathogenesis, immunogenicity and immune evasion mechanisms of E. tenella.

  5. Identification of common immunodominant antigens of Eimeria tenella, Eimeria acervulina and Eimeria maxima by immunoproteomic analysis.

    Science.gov (United States)

    Liu, Lianrui; Huang, Xinmei; Liu, Jianhua; Li, Wenyu; Ji, Yihong; Tian, Di; Tian, Lu; Yang, Xinchao; Xu, Lixin; Yan, Ruofeng; Li, Xiangrui; Song, Xiaokai

    2017-05-23

    Clinical chicken coccidiosis is mostly caused by simultaneous infection of several Eimeria species, and host immunity against Eimeria is species-specific. It is urgent to identify common immunodominant antigen of Eimeria for developing multivalent anticoccidial vaccines. In this study, sporozoite proteins of Eimeria tenella, Eimeria acervulina and Eimeria maxima were analyzed by two-dimensional electrophoresis (2DE). Western bot analysis was performed on the yielded 2DE gel using antisera of E. tenella E. acervulina and E. maxima respectively. Next, the detected immunodominant spots were identified by comparing the data from MALDI-TOF-MS/MS with available databases. Finally, Eimeria common antigens were identified by comparing amino acid sequence between the three Eimeria species. The results showed that analysis by 2DE of sporozoite proteins detected 629, 626 and 632 protein spots from E. tenella, E. acervulina and E. maxima respectively. Western bot analysis revealed 50 (E. tenella), 64 (E. acervulina) and 57 (E. maxima) immunodominant spots from the sporozoite 2DE gels of the three Eimeria species. The immunodominant spots were identified as 33, 27 and 25 immunodominant antigens of E. tenella, E. acervulina and E. maxima respectively. Fifty-four immunodominant proteins were identified as 18 ortholog proteins among the three Eimeria species. Finally, 5 of the 18 ortholog proteins were identified as common immunodominant antigens including elongation factor 2 (EF-2), 14-3-3 protein, ubiquitin-conjugating enzyme domain-containing protein (UCE) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). In conclusion, our results not only provide Eimeria sporozoite immunodominant antigen map and additional immunodominant antigens, but also common immunodominant antigens for developing multivalent anticoccidial vaccines.

  6. TLR4 and Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Jane J. Kim

    2010-01-01

    Full Text Available Chronic inflammation is a key feature of insulin resistance and obesity. Toll-Like Receptor 4 (TLR4, involved in modulating innate immunity, is an important mediator of insulin resistance and its comorbidities. TLR4 contributes to the development of insulin resistance and inflammation through its activation by elevated exogenous ligands (e.g., dietary fatty acids and enteric lipopolysaccharide and endogenous ligands (e.g., free fatty acids which are elevated in obese states. TLR4, expressed in insulin target tissues, activates proinflammatory kinases JNK, IKK, and p38 that impair insulin signal transduction directly through inhibitory phosphorylation of insulin receptor substrate (IRS on serine residues. TLR4 activation also leads to increased transcription of pro-inflammatory genes, resulting in elevation of cytokine, chemokine, reactive oxygen species, and eicosanoid levels that promote further insulin-desensitization within the target cell itself and in other cells via paracrine and systemic effects. Increased understanding of cell type-specific TLR4-mediated effects on insulin action present the opportunity and challenge of developing related therapeutic approaches for improving insulin sensitivity while preserving innate immunity.

  7. Sensitive and specific identification by polymerase chain reaction of Eimeria tenella and Eimeria maxima, important protozoan pathogens in laboratory avian facilities.

    Science.gov (United States)

    Lee, Hyun-A; Hong, Sunhwa; Chung, Yungho; Kim, Okjin

    2011-09-01

    Eimeria tenella and Eimeria maxima are important pathogens causing intracellular protozoa infections in laboratory avian animals and are known to affect experimental results obtained from contaminated animals. This study aimed to find a fast, sensitive, and efficient protocol for the molecular identification of E. tenella and E. maxima in experimental samples using chickens as laboratory avian animals. DNA was extracted from fecal samples collected from chickens and polymerase chain reaction (PCR) analysis was employed to detect E. tenella and E. maxima from the extracted DNA. The target nucleic acid fragments were specifically amplified by PCR. Feces secreting E. tenella and E. maxima were detected by a positive PCR reaction. In this study, we were able to successfully detect E. tenella and E. maxima using the molecular diagnostic method of PCR. As such, we recommended PCR for monitoring E. tenella and E. maxima in laboratory avian facilities.

  8. Field abundance and nest structure of the ant Anoplolepis tenella associated with the African root and tuber scale in the Congo Basin

    OpenAIRE

    Fotso Kuate, A.; Tindo, M.; Hanna, R.; Kenne, M.; Goergen, G.

    2006-01-01

    Anoplolepis tenella is a ground-dwelling ant of the tropical forest zone of Central Africa. It is associated with the African root and tuber scale (ARTS), Stictococcus vayssierei Richard, an emerging cassava pest in the zone. Developing sustainable and effective methods to control ARTS requires basic knowledge of the biology of A. tenella and the nature of interactions between the two insects. A study on the nest distribution and composition of A. tenella in various vegetation types prevailin...

  9. TLR3 and TLR4 expression in healthy and diseased human endometrium

    Directory of Open Access Journals (Sweden)

    Kimmig Rainer

    2008-09-01

    Full Text Available Abstract Background Toll-like receptors (TLRs play an essential role in the innate immune system by initiating and directing immune response to pathogens. TLRs are expressed in the human endometrium and their regulation might be crucial for the pathogenesis of endometrial diseases. Methods TLR3 and TLR4 expression was investigated during the menstrual cycle and in postmenopausal endometrium considering peritoneal endometriosis, hyperplasia, and endometrial adenocarcinoma specimens (grade 1 to 3. The expression studies applied quantitative RT-PCR and immunolabelling of both proteins. Results TLR3 and TLR4 proteins were mostly localised to the glandular and luminal epithelium. In addition, TLR4 was present on endometrial dendritic cells, monocytes and macrophages. TLR3 and TLR4 mRNA levels did not show significant changes during the menstrual cycle. In patients with peritoneal endometriosis, TLR3 and TLR4 mRNA expression decreased significantly in proliferative diseased endometrium compared to controls. Interestingly, ectopic endometriotic lesions showed a significant increase of TLR3 und TLR4 mRNA expression compared to corresponding eutopic tissues, indicating a local gain of TLR expression. Endometrial hyperplasia and adenocarcinoma revealed significantly reduced receptor levels when compared with postmenopausal controls. The lowest TLR expression levels were determined in poor differentiated carcinoma (grade 3. Conclusion Our data suggest an involvement of TLR3 and TLR4 in endometrial diseases as demonstrated by altered expression levels in endometriosis and endometrial cancer.

  10. Use of Eimeria tenella radiovaccine for immunoprophylaxis in fowl against coccidiosis

    International Nuclear Information System (INIS)

    Jungmann, R.; Mielke, D.

    1989-01-01

    Studies were conducted into oral immunization of broilers, using a widely standardized coccidiosis vaccine attenuated by irradiation with 250 Gy (Eimeria tenella radiovaccine). The method was applied to 2,567 animals kept in floor pens and to another 21,620 animals under production conditions. Profound immunity was thus built up to last from three weeks after vaccination to slaughter maturity. Immunized chickens challenged with E. tenella develope no clinical infection, whereas the non-immunized ones showed an intensive haemorrhagic enteritis with 88% of lethality. The total output of coccidiaoocysts of immunized chickens decreased to more than 95% compared to the non-immunized ones. These results were reproducible in six different experimental groups. (author)

  11. Quantitative proteomic studies in resistance mechanisms of Eimeria tenella against polyether ionophores.

    Science.gov (United States)

    Thabet, Ahmed; Honscha, Walther; Daugschies, Arwid; Bangoura, Berit

    2017-05-01

    Polyether ionophores are widely used to treat and control coccidiosis in chickens. Widespread use of anticoccidials resulted in worldwide resistance. Mechanisms of resistance development and expansion are complex and poorly understood. Relative proteomic quantification using LC-MS/MS was used to compare sensitive reference strains (Ref-1, Ref-2) with putatively resistant and moderately sensitive field strains (FS-R, FS-mS) of Eimeria tenella after isotopic labelling with tandem mass tags (TMT). Ninety-seven proteins were identified, and 25 of them were regulated. Actin was significantly upregulated in resistant strains in comparison with their sensitive counterparts. On the other hand, microneme protein (MIC4) was downregulated in resistant strains. Optimization of labelling E. tenella sporozoites by TMT might identify further proteins that play a role in the obvious complex mechanism leading to resistance against Monensin.

  12. Molecular Characterization and Analysis of a Novel Protein Disulfide Isomerase-Like Protein of Eimeria tenella

    OpenAIRE

    Han, Hongyu; Dong, Hui; Zhu, Shunhai; Zhao, Qiping; Jiang, Lianlian; Wang, Yange; Li, Liujia; Wu, Youlin; Huang, Bing

    2014-01-01

    Protein disulfide isomerase (PDI) and PDI-like proteins are members of the thioredoxin superfamily. They contain thioredoxin-like domains and catalyze the physiological oxidation, reduction and isomerization of protein disulfide bonds, which are involved in cell function and development in prokaryotes and eukaryotes. In this study, EtPDIL, a novel PDI-like gene of Eimeria tenella, was cloned using rapid amplification of cDNA ends (RACE) according to the expressed sequence tag (EST). The EtPDI...

  13. Assessment of humoral immunity to Eimeria tenella sporozoites in chickens by ELISA

    Directory of Open Access Journals (Sweden)

    S. Saravanan

    2014-07-01

    Full Text Available Aim: To assess the humoral immune response of Eimeria tenella sporozoites in broiler chickens by a developed enzyme linked immunosorbent assay (ELISA and the efficacy in terms of bodyweight, lesion score and oocysts excretion in immunized broilers. Materials and Methods: Purified live E. tenella sporozoites were administered subcutaneously in neck region of broiler chickens in the early life (first week at different concentrations. The potency of the sporozoite vaccine as assessed by IgG levels and the performance in immunized broilers as assessed by body weight, lesion score and oocysts excretion in faeces after challenge with 10, 000 live E. tenella oocysts at 49 days of age were evaluated. Results: The chickens of group (T4 immunized with 20 µg of antigen on day 6 showed an increase in IgG levels (0.161±0.004 two weeks post immunization (PI peaking (0.399± 0.016 at 5 weeks PI. The mean weekly weight gain (g after challenge, at 56 days of age was high in T4 (148±4.751 g with a low mean lesion score (2.5±0.22 and mean oocyst output (x103 oocytes per gram (OPG in faeces (100.3± 45.72 when compared to unimmunised infected controls. Conclusion: An early but partial immune response against caecal coccidiosis could be achieved by immunization with E. tenella specific sporozoites in chickens of less than a week old. Moreover, the performance of immunized chickens as indicated by weight gain, lesion score and oocyst output was found to be superior to the unimmunized infected controls.

  14. Anticoccidial activity of hydrochloric acid (HCl against Eimeria tenella in broiler chickens

    Directory of Open Access Journals (Sweden)

    Rao Z Abbas

    2011-05-01

    Full Text Available The present study was planned to evaluate the anticoccidial activity of the different concentrations of the HCl against Eimeria tenella infection in broiler chickens in comparison with the amprolium anticoccidial. For this purpose, a total of 198 chicks were placed 11 per pen with three pens per treatment. The different concentrations of HCl (1000ppm, 2000ppm and 3000ppm and amproilum (at the dose rate of 125ppm were given to the experimental groups in drinking water from 10 to 19th days of age. One group was kept as infected non medicated control and one as non infected non medicated control. At the 12th day of age, all the groups were inoculated orally with 75,000 sporulated oocysts except non infected non medicated control. Anticoccidial activity was evaluated on the basis of performance (weight gain, feed conversion ratio and pathogenic (oocyst score, lesion score and mortality %age parameters. Among HCl medicated groups, the maximum anticoccidial effect was seen in the group medicated with 1000ppm HCl followed by 2000ppm and 3000ppm HCl medicated groups. Amprolium and 1000ppm HCl were almost equivalent in suppressing the negative performance and pathogenic effects associated with coccidiosis (Eimeria tenella challenge. In summary, the lower doses of HCl have the potential to be used as alternative to chemotherapeutic drugs for Eimeria tenella control. It is therefore suggested that further studies should be carried out to determine the possible minimum safe levels of HCl with least toxic effects to be used as anticoccidial.

  15. Anti-coccidial activity of the ethanol extract of Tribulus terrestris fruits on Eimeria tenella

    Science.gov (United States)

    Hong, Sunhwa; Moon, Mi-Na; Im, Eun-Kyung; Won, Jum-Soon; Yoo, Ji-Hyun

    2018-01-01

    Anti-coccidial effects of the fruits of Tribulus terrestris (Tribuli fructus) ethanol extract (TTE) were studied with animal experiment following per oral administration with Eimeria (E.) tenella. This experiment was performed on the 3-day-old chicks (n=30). The animals were divided with 3 groups; TFE 15mg per animal+infected (n=10), TTE untreated+infected (n=10) and non-infected control (n=10). Animals were administrated with or without TTE during 1 week, and then inoculated with E. tenella. The anti-coccidial activity were evaluated with oocysts shedding numbers in stools, body weights changes and food intake changes. The TTE-inoclated animals revealed significantly decreased stool oocysts numbers (P<0.05) when compared to the TTE untreated animals. Also, TTE-treated animals showed more increased body weight gains (P<0.05) than the TTE untreated animals. These results demonstrate that TTE produce anticoccidial activities against E. tenella. TTE could be a promising treatment for the coccidiosis. PMID:29628976

  16. Anti-coccidial activity of the ethanol extract of Tribulus terrestris fruits on Eimeria tenella.

    Science.gov (United States)

    Hong, Sunhwa; Moon, Mi-Na; Im, Eun-Kyung; Won, Jum-Soon; Yoo, Ji-Hyun; Kim, Okjin

    2018-03-01

    Anti-coccidial effects of the fruits of Tribulus terrestris (Tribuli fructus) ethanol extract (TTE) were studied with animal experiment following per oral administration with Eimeria ( E .) tenella . This experiment was performed on the 3-day-old chicks (n=30). The animals were divided with 3 groups; TFE 15mg per animal+infected (n=10), TTE untreated+infected (n=10) and non-infected control (n=10). Animals were administrated with or without TTE during 1 week, and then inoculated with E. tenella . The anti-coccidial activity were evaluated with oocysts shedding numbers in stools, body weights changes and food intake changes. The TTE-inoclated animals revealed significantly decreased stool oocysts numbers ( P <0.05) when compared to the TTE untreated animals. Also, TTE-treated animals showed more increased body weight gains ( P <0.05) than the TTE untreated animals. These results demonstrate that TTE produce anticoccidial activities against E. tenella . TTE could be a promising treatment for the coccidiosis.

  17. Monitoring of local CD8 β-expressing cell populations during Eimeria tenella infection of naïve and immune chickens

    DEFF Research Database (Denmark)

    Wattrang, Eva; Thebo, Per; Lunden, Anna

    2016-01-01

    The purpose of this study was to monitor abundance and activation of local CD8β-expressing T-cell populations during Eimeria tenella infections of naïve chickens and chickens immune by previous infections. Chickens were infected with E. tenella up to three times. Caecal T-cell receptor (TCR) γ...

  18. Innate immune receptors in human airway smooth muscle cells: activation by TLR1/2, TLR3, TLR4, TLR7 and NOD1 agonists.

    Directory of Open Access Journals (Sweden)

    Anne Månsson Kvarnhammar

    Full Text Available BACKGROUND: Pattern-recognition receptors (PRRs, including Toll-like receptors (TLRs, NOD-like receptors (NLRs and RIG-I-like receptors (RLRs, recognize microbial components and trigger a host defense response. Respiratory tract infections are common causes of asthma exacerbations, suggesting a role for PRRs in this process. The present study aimed to examine the expression and function of PRRs on human airway smooth muscle cells (HASMCs. METHODS: Expression of TLR, NLR and RLR mRNA and proteins was determined using real-time RT-PCR, flow cytometry and immunocytochemistry. The functional responses to ligand stimulation were investigated in terms of cytokine and chemokine release, cell surface marker expression, proliferation and proteins regulating the contractile state. RESULTS: HASMCs expressed functional TLR2, TLR3, TLR4, TLR7 and NOD1. Stimulation with the corresponding agonists Pam3CSK4, poly(I:C, LPS, R-837 and iE-DAP, respectively, induced IL-6, IL-8 and GM-CSF release and up-regulation of ICAM-1 and HLA-DR, while poly(I:C also affected the release of eotaxin and RANTES. The proliferative response was slightly increased by LPS. Stimulation, most prominently with poly(I:C, down-regulated myosin light chain kinase and cysteinyl leukotriene 1 receptor expression and up-regulated β2-adrenoceptor expression. No effects were seen for agonist to TLR2/6, TLR5, TLR8, TLR9, NOD2 or RIG-I/MDA-5. CONCLUSION: Activation of TLR2, TLR3, TLR4, TLR7 and NOD1 favors a synthetic phenotype, characterized by an increased ability to release inflammatory mediators, acquire immunomodulatory properties by recruiting and interacting with other cells, and reduce the contractile state. The PRRs might therefore be of therapeutic use in the management of asthma and infection-induced disease exacerbations.

  19. Ontogenia do fruto em desenvolvimento de Alternanthera tenella Colla e Amaranthus blitum Linnaeus (Amaranthaceae Ontogeny of fruits of Alternanthera tenella Colla and Amaranthus blitum Linnaeus (Amaranthaceae

    Directory of Open Access Journals (Sweden)

    Vanessa de Carvalho Harthman

    2012-09-01

    Full Text Available Alternanthera tenella Colla e Amaranthus blitum Linnaeus são espécies invasoras que ocorrem em culturas e terrenos baldios na região de Maringá, Paraná. O trabalho teve por objetivo a análise morfoanatômica dos frutos em desenvolvimento e estruturas não pericárpicas dessas duas espécies, com a finalidade de contribuir com informações estruturais para identificação das espécies, classificação dos frutos e investigações ecológicas. Flores e frutos foram coletados no campus da Universidade Estadual de Maringá, fixados em Glutaraldeído, secionados em micrótomo de rotação e corados com a azul de Toluidina. As bractéolas e perigônio são persistentes nos frutos e têm estrutura diferente nas duas espécies. O aquênio de Alternanthera tenella mantém o mesmo número de estratos celulares que o ovário, que sofrem colapso na fase madura, exceto o mesocarpo interno que se mantém com espessamento parietal em U e cristais. O utrículo de Amaranthus blitum é semelhante ao ovário em número de camadas celulares e apresenta aerênquima quando maduro. As sementes maduras são exotestais, com mesotesta e endotesta colapsadas, e embrião curvo. Nesse estudo, foram registrados alguns caracteres estruturais dos perigônios e dos frutos que são potencialmente significativos para caracterização e separação das espécies, ao contrário das sementes que são muito semelhantes.Alternanthera tenella Colla and Amaranthus blitum Linnaeus are weeds that occur in crops and uncultivated areas in the Maringá region of Paraná. In this study, a morphoanatomical analysis of fruit development and the pericarp of A. tenella and A. blitum was made in order to contribute structural information for species identification, fruit classification, and ecological investigations. Flowers and fruits were collected at the campus of the State University of Maringá, Paraná, fixed in glutaraldehyde, sectioned with a rotary microtome and stained with

  20. TLR4 activates NF-κB in human ovarian granulosa tumor cells

    International Nuclear Information System (INIS)

    Woods, Dori C.; White, Yvonne A.R.; Dau, Caroline; Johnson, A.L.

    2011-01-01

    Highlights: → TLR4 is expressed in human ovarian granulosa tumor cells. → Acting through TLR4, LPS and HSP60 induce a NFκB signaling cascade in human ovarian granulosa tumor cells. → NFκB activation or inhibition did not alter chemosensitivity to TRAIL or cisplatin. -- Abstract: Previous studies have demonstrated expression of Toll-like receptors (TLRs) in the surface epithelium of normal ovaries (OSE) and in epithelial ovarian tumors. Most notably, OSE-derived cancers express TLR4, which activates the nuclear factor-kappa B (NF-κB) signaling cascade as a mediator of inflammatory response. Currently, there is considerable interest in elucidating the role of TLR-mediated signaling in cancers. Nevertheless, the expression of TLRs in granulosa cell tumors (GCTs) of the ovary, and the extent to which GCT expression of TLRs may influence cell-signaling pathways and/or modulate the efficacy of chemotherapeutics, has yet to be determined. In the present study, human GCT lines (COV434 and KGN) were utilized to evaluate expression of functional TLR4. TLR4 is expressed in GCT cell lines and ligation of TLR4 with bacterial lipopolysaccharide (LPS) led to IκB degradation and activation of NF-κB. NF-κB activation was confirmed by nuclear localization of NF-κB p65 following treatment with LPS and the naturally occurring ligand, HSP60. Notably, immunoneutralization of TLR4 blocked nuclear localization, and inhibition of NF-κB signaling attenuated LPS-induced TNFα plus increased doubling time in both cell lines. Contradictory to reports using human OSE cell lines, inhibition of NF-κB signaling failed to sensitize GCT lines to TRAIL or cisplatin. In summary, findings herein are the first to demonstrate a functional TLR-signaling pathway specifically in GCTs, and indicate that in contrast to OSE-derived cancers, inhibition of NF-κB does not sensitize GCTs to TRAIL or cisplatin.

  1. Mucolipin 1 positively regulates TLR7 responses in dendritic cells by facilitating RNA transportation to lysosomes.

    Science.gov (United States)

    Li, Xiaobing; Saitoh, Shin-Ichiroh; Shibata, Takuma; Tanimura, Natsuko; Fukui, Ryutaro; Miyake, Kensuke

    2015-02-01

    Toll-like receptor 7 (TLR7) and TLR9 sense microbial single-stranded RNA (ssRNA) and ssDNA in endolysosomes. Nucleic acid (NA)-sensing in endolysosomes is thought to be important for avoiding TLR7/9 responses to self-derived NAs. Aberrant self-derived NA transportation to endolysosomes predisposes to autoimmune diseases. To restrict NA-sensing in endolysosomes, TLR7/9 trafficking is tightly controlled by a multiple transmembrane protein Unc93B1. In contrast to TLR7/9 trafficking, little is known about a mechanism underlying NA transportation. We here show that Mucolipin 1 (Mcoln1), a member of the transient receptor potential (TRP) cation channel gene family, has an important role in ssRNA trafficking into lysosomes. Mcoln1(-/-) dendritic cells (DCs) showed impaired TLR7 responses to ssRNA. A mucolipin agonist specifically enhanced TLR7 responses to ssRNAs. The channel activity of Mcoln1 is activated by a phospholipid phosphatidylinositol (3,5) bisphosphate (PtdIns(3,5)P2), which is generated by a class III lipid kinase PIKfyve. A PIKfyve inhibitor completely inhibited TLR7 responses to ssRNA in DCs. Confocal analyses showed that ssRNA transportation to lysosomes in DCs was impaired by PIKfyve inhibitor as well as by the lack of Mcoln1. Transportation of TLR9 ligands was also impaired by the PIKfyve inhibitor. These results demonstrate that the PtdIns(3,5)P2-Mcoln1 axis has an important role in ssRNA transportation into lysosomes in DCs. © The Japanese Society for Immunology. 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. TLR-4 polymorphisms and leukocyte TLR-4 expression in febrile UTI and renal scarring.

    Science.gov (United States)

    Bayram, Meral Torun; Soylu, Alper; Ateş, Halil; Kızıldağ, Sefa; Kavukçu, Salih

    2013-09-01

    In this study, we aimed to determine the relation of TLR-4 Asp299Gly and Thr399Ile polymorphisms and monocyte/neutrophil TLR-4 expression to febrile urinary tract infection (UTI) and renal scar development in children. The study was performed in children with a history of febrile UTI. Patients with and without renal scarring were classified as group 1 and group 2, respectively, while the control cases in our previous study were used as the control group (group 3). All three groups were compared for the rate of TLR-4 Asp299Gly and Thr399Ile polymorphisms, and for basal and lipopolysaccharide-stimulated monocyte/neutrophil TLR-4 expression levels. There were 168 patients (86 in group 1, 82 in group 2) and 120 control cases. Monocyte/neutrophil TLR-4 expression levels were similar in groups 1 and 2. However, both groups had lower TLR-4 expression than group 3. The rate of TLR-4 Asp299Gly polymorphism was not different in all groups. TLR-4 Thr399Ile polymorphism was higher in groups 1 and 2 than in group 3 (14.0, 12.2, and 2.0 %, respectively), while group 1 and group 2 were not different. Furthermore, monocyte TLR-4 expression level was lower in those having TLR-4 Thr399Ile polymorphism than in those without this polymorphism. Patients with febrile UTI had more frequent TLR-4 Thr399Ile polymorphism and lower monocyte/neutrophil TLR-4 expression. These findings indicate that children carrying TLR-4 Thr399Ile polymorphism and/or having low level of monocyte/neutrophil TLR-4 expression have a tendency to develop febrile UTI. However, we could not show the association of TLR-4 polymorphisms and of TLR-4 expression level to renal scarring.

  3. Profil Saraf Nitrergik Sekum Ayam Pedaging yang Diinfeksi Eimeria tenella (THE PROFILE OF NEORAL NITRERGIC IN THE COECUM OF BROILER INFECTED WITH Emeria tenella

    Directory of Open Access Journals (Sweden)

    Amelia Hana

    2016-01-01

    Full Text Available Neurotransmitter found in the enteric nervous system that plays an important role in a variety ofenteropathies, including inflammatory bowel disease. Alteration of nitrergic neurons has been reported to bedependent on the manner by which inflammation is caused. This study was performed to determine theprofile of neural nitrergic with Nicotinamide Adenine Dinucleotide Phosphate-diaphorase (NADPH-dstaining in the cecum of broiler infected by Eimeria tenella (E. tenella. Thirty six health free of coccidiosisbroiler one-day old chickens (DOC used in this study. All of broiler adapted for 7 days with food and drinkgiven ad libitum then divided into three groups, each group consisted of 12 broilers. The 1st group wascontrol only given orally 1.0 ml of distilled water/ heads , while 2nd group was infected with a single dose of5x103 oocysts/ head orally, and 3rd group was infected with a single dose of 2x104 oocysts/ head orally. Onday 7 post infection, all of chickens were fasted for 12 hours then were euthanized and cecum was taken.Lesion score of cecum was assessed. Furthermore, tissue of the coecum was prepared for hisochemicalusing NADPH-d staining to determine morphology, and morhometric of nitrergic neurons. The resultshown that cecum lesion score of group I is 0, group II is +2, group III is +3. Neuron density in the cecum ofgroup I is 2794.96+4.65 neuron/cm2, group II is 4930.36+63.73 neuron/cm2 and group III is 7892.31+44.97 neuron/cm2. Neuron density of group II and III increased signifcantly (p<001 than group I. Nitrergic neurondesity of group III increased significantly (p<0.05 than that of group II. It was concluded that the infectionof E.tenella led to increase the number of neutrl mienteric nitrergic of the cecum. The higher lesion score ofcecum led to increase the number of mienteric nitrergic neuron.

  4. Stable Toll-Like Receptor 10 Knockdown in THP-1 Cells Reduces TLR-Ligand-Induced Proinflammatory Cytokine Expression

    Directory of Open Access Journals (Sweden)

    Hai Van Le

    2016-06-01

    Full Text Available Toll-like receptor 10 (TLR10 is the only orphan receptor whose natural ligand and function are unknown among the 10 human TLRs. In this study, to test whether TLR10 recognizes some known TLR ligands, we established a stable TLR10 knockdown human monocytic cell line THP-1 using TLR10 short hairpin RNA lentiviral particle and puromycin selection. Among 60 TLR10 knockdown clones that were derived from each single transduced cell, six clones were randomly selected, and then one of those clones, named E7, was chosen for the functional study. E7 exhibited approximately 50% inhibition of TLR10 mRNA and protein expression. Of all the TLRs, only the expression of TLR10 changed significantly in this cell line. Additionally, phorbol 12-myristate 13-acetate-induced macrophage differentiation of TLR10 knockdown cells was not affected in the knockdown cells. When exposed to TLR ligands, such as synthetic diacylated lipoprotein (FSL-1, lipopolysaccharide (LPS, and flagellin, significant induction of proinflammatory cytokine gene expression including Interleukin-8 (IL-8, Interleukin-1 beta (IL-1β, Tumor necrosis factor-alpha (TNF-α and Chemokine (C–C Motif Ligand 20 (CCL20 expression, was found in the control THP-1 cells, whereas the TLR10 knockdown cells exhibited a significant reduction in the expression of IL-8, IL-1β, and CCL20. TNF-α was the only cytokine for which the expression did not decrease in the TLR10 knockdown cells from that measured in the control cells. Analysis of putative binding sites for transcription factors using a binding-site-prediction program revealed that the TNF-α promoter does not have putative binding sites for AP-1 or c-Jun, comprising a major transcription factor along with NF-κB for TLR signaling. Our results suggest that TLR10 is involved in the recognition of FSL-1, LPS, and flagellin and TLR-ligand-induced expression of TNF-α does not depend on TLR10.

  5. Stable Toll-Like Receptor 10 Knockdown in THP-1 Cells Reduces TLR-Ligand-Induced Proinflammatory Cytokine Expression.

    Science.gov (United States)

    Le, Hai Van; Kim, Jae Young

    2016-06-01

    Toll-like receptor 10 (TLR10) is the only orphan receptor whose natural ligand and function are unknown among the 10 human TLRs. In this study, to test whether TLR10 recognizes some known TLR ligands, we established a stable TLR10 knockdown human monocytic cell line THP-1 using TLR10 short hairpin RNA lentiviral particle and puromycin selection. Among 60 TLR10 knockdown clones that were derived from each single transduced cell, six clones were randomly selected, and then one of those clones, named E7, was chosen for the functional study. E7 exhibited approximately 50% inhibition of TLR10 mRNA and protein expression. Of all the TLRs, only the expression of TLR10 changed significantly in this cell line. Additionally, phorbol 12-myristate 13-acetate-induced macrophage differentiation of TLR10 knockdown cells was not affected in the knockdown cells. When exposed to TLR ligands, such as synthetic diacylated lipoprotein (FSL-1), lipopolysaccharide (LPS), and flagellin, significant induction of proinflammatory cytokine gene expression including Interleukin-8 (IL-8), Interleukin-1 beta (IL-1β), Tumor necrosis factor-alpha (TNF-α) and Chemokine (C-C Motif) Ligand 20 (CCL20) expression, was found in the control THP-1 cells, whereas the TLR10 knockdown cells exhibited a significant reduction in the expression of IL-8, IL-1β, and CCL20. TNF-α was the only cytokine for which the expression did not decrease in the TLR10 knockdown cells from that measured in the control cells. Analysis of putative binding sites for transcription factors using a binding-site-prediction program revealed that the TNF-α promoter does not have putative binding sites for AP-1 or c-Jun, comprising a major transcription factor along with NF-κB for TLR signaling. Our results suggest that TLR10 is involved in the recognition of FSL-1, LPS, and flagellin and TLR-ligand-induced expression of TNF-α does not depend on TLR10.

  6. DMPD: TLR ignores methylated RNA? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16111629 TLR ignores methylated RNA? Ishii KJ, Akira S. Immunity. 2005 Aug;23(2):11...1-3. (.png) (.svg) (.html) (.csml) Show TLR ignores methylated RNA? PubmedID 16111629 Title TLR ignores methylated

  7. Structure Based Modeling of Small Molecules Binding to the TLR7 by Atomistic Level Simulations

    Directory of Open Access Journals (Sweden)

    Francesco Gentile

    2015-05-01

    Full Text Available Toll-Like Receptors (TLR are a large family of proteins involved in the immune system response. Both the activation and the inhibition of these receptors can have positive effects on several diseases, including viral pathologies and cancer, therefore prompting the development of new compounds. In order to provide new indications for the design of Toll-Like Receptor 7 (TLR7-targeting drugs, the mechanism of interaction between the TLR7 and two important classes of agonists (imidazoquinoline and adenine derivatives was investigated through docking and Molecular Dynamics simulations. To perform the computational analysis, a new model for the dimeric form of the receptors was necessary and therefore created. Qualitative and quantitative differences between agonists and inactive compounds were determined. The in silico results were compared with previous experimental observations and employed to define the ligand binding mechanism of TLR7.

  8. Study on the immunogenic ability of Eimeria tenella oocytes following treatment with gamma rays

    International Nuclear Information System (INIS)

    Penev, P.; Stafanova, M.

    1975-01-01

    Studied was the immunizing capacity of Eimeria tenella oocytes, treated with gamma rays at the rate of 6000 R, in 10- and 20-day-old chickens. The oocytes sporulated after treatment. Applied at the rate of 50,000 R they showed lower virulence and were capable of inducing resistance to reinfection with non-irradiated oocytes at rates that were three times as much. Following reinfection some birds manifested subclinical coccidiosis but survived. This showed that the immunization with oocytes that had been irradiated with 6,000 R had its peculiar aspects. (author)

  9. Cell Surface Trafficking of TLR1 Is Differentially Regulated by the Chaperones PRAT4A and PRAT4B*

    Science.gov (United States)

    Hart, Bryan E.; Tapping, Richard I.

    2012-01-01

    The subcellular localization of Toll-like receptors (TLRs) is critical to their ability to function as innate immune sensors of microbial infection. We previously reported that an I602S polymorphism of human TLR1 is associated with aberrant trafficking of the receptor to the cell surface, loss of responses to TLR1 agonists, and differential susceptibility to diseases caused by pathogenic mycobacteria. Through an extensive analysis of receptor deletion and point mutants we have discovered that position 602 resides within a short 6 amino acid cytoplasmic region that is required for TLR1 surface expression. This short trafficking motif, in conjunction with the adjacent transmembrane domain, is sufficient to direct TLR1 to the cell surface. A serine at position 602 interrupts this trafficking motif and prevents cell surface expression of TLR1. Additionally, we have found that ER-resident TLR chaperones, PRAT4A and PRAT4B, act as positive and negative regulators of TLR1 surface trafficking, respectively. Importantly, either over-expression of PRAT4A or knock-down of PRAT4B rescues cell surface expression of the TLR1 602S variant. We also report that IFN-γ treatment of primary human monocytes derived from homozygous 602S individuals rescues TLR1 cell surface trafficking and cellular responses to soluble agonists. This event appears to be mediated by PRAT4A whose expression is strongly induced in human monocytes by IFN-γ. Collectively, these results provide a mechanism for the differential trafficking of TLR1 I602S variants, and highlight the distinct roles for PRAT4A and PRAT4B in the regulation of TLR1 surface expression. PMID:22447933

  10. Genomic evidence of gene duplication and adaptive evolution of Toll like receptors (TLR2 and TLR4) in reptiles.

    Science.gov (United States)

    Shang, Shuai; Zhong, Huaming; Wu, Xiaoyang; Wei, Qinguo; Zhang, Huanxin; Chen, Jun; Chen, Yao; Tang, Xuexi; Zhang, Honghai

    2018-04-01

    Toll-like receptors (TLRs) encoded by the TLR multigene family play an important role in initial pathogen recognition in vertebrates. Among the TLRs, TLR2 and TLR4 may be of particular importance to reptiles. In order to study the evolutionary patterns and structural characteristics of TLRs, we explored the available genomes of several representative members of reptiles. 25 TLR2 genes and 19 TLR4 genes from reptiles were obtained in this study. Phylogenetic results showed that the TLR2 gene duplication occurred in several species. Evolutionary analysis by at least two methods identified 30 and 13 common positively selected codons in TLR2 and TLR4, respectively. Most positively selected sites of TLR2 and TLR4 were located in the Leucine-rich repeat (LRRs). Branch model analysis showed that TLR2 genes were under different evolutionary forces in reptiles, while the TLR4 genes showed no significant selection pressure. The different evolutionary adaptation of TLR2 and TLR4 among the reptiles might be due to their different function in recognizing bacteria. Overall, we explored the structure and evolution of TLR2 and TLR4 genes in reptiles for the first time. Our study revealed valuable information regarding TLR2 and TLR4 in reptiles, and provided novel insights into the conservation concern of natural populations. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. EVALUATION OF THE ANTIGENICITY AND IMMUNOGENICITY OF Eimeria tenella BY REPRODUCTIVE INDEX AND HISTOPATHOLOGICAL CHANGES OF CECAL COCCIDIOSIS VIRULENT LIVE VACCINE IN BROILER CHICKENS.

    Science.gov (United States)

    Suprihati, Endang; Yunus, Muchammad

    2018-01-01

    The development of vaccine to control coccidiosis caused by Eimeria tenella ( E. tenella ) in chickens is intensifying because of the increasing threat of drug resistance to anticoccidial agents. It is important, therefore, to develop a reliable standard method for the assessment of vaccine afficacy particularly antigenicity and immunogenicity become crucial. Evaluation of E. tenella antigenicity and immunogenicity to some low doses can be reflected by reproductive index and histopathological changes. The complete random design of research was used in this study. Sixty of two weeks old broilers were divided into four groups and each group composed 15 replications. The group 1 was chicken group without virulent E. tenella oocyst inoculation. The group 2, 3 and group 4 were chicken group inoculated with virulent E. tenella oocyst at doses of 1.0 x 10 2 , 2.0 x 10 2 , 3.0 x 10 2 , respectively. Then all chicken groups were challenged with E. tenella oocyst at doses of 1.0 x 10 3 . Observation of research that represented antigenicity and immunogenicity was clinical sign, reproductive index, histopathological changes. On virulent E. tenella inoculation step, some clinical signs such as appetite, weakness, and diarrhea were very slight on all chicken groups. While on challenge test step, there were no clinical signs of all chicken groups except the group 1. For the reproductive index of virulent E. tenella inoculation step, there were no significantly differences in all chicken groups except the group 1. As reproductive index, the same result pattern was seen for histopathological changes. The low number virulent E. tenella had low reproductive index and few histopathological changes effect that represents a promising strategy to prevent cecal coccidiosis in chickens.

  12. Potassium 4-(hydroxymethyl)-benzenosulfonate: a novel metabolite isolated from the marine red alga Bostrychia tenella (Rhodomelaceae, ceramiales); 4-(Hidroximetil)-Benzenossulfonato de potassio: metabolito inedito isolado da alga marinha Bostrychia tenella (Rhodomelaceae, ceramiales)

    Energy Technology Data Exchange (ETDEWEB)

    Felicio, Rafael de; Debonsi, Hosana Maria [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas. Dept. de Fisica e Quimica]. E-mail: hosana@fcfrp.usp.br; Yokoya, Nair Sumie [Instituto de Botanica de Sao Paulo, SP (Brazil). Secao de Ficologia

    2008-07-01

    Chemical investigation of the dichloromethane/methanol extract of the marine alga Bostrychia tenella has led to the isolation of two aromatic compounds, the new sulfate metabolite potassium 4-(hydroxymethyl)-benzenosulfonate (1) and the compound 1-methoxyphenethyl alcohol (2), described previously as a synthetic product. Their structures were determined by spectroscopic methods including NMR, MS, IR and by comparison with literature data. (author)

  13. Rationally Designed TLR4 Ligands for Vaccine Adjuvant Discovery

    Directory of Open Access Journals (Sweden)

    Kelsey A. Gregg

    2017-05-01

    Full Text Available Adjuvant properties of bacterial cell wall components like MPLA (monophosphoryl lipid A are well described and have gained FDA approval for use in vaccines such as Cervarix. MPLA is the product of chemically modified lipooligosaccharide (LOS, altered to diminish toxic proinflammatory effects while retaining adequate immunogenicity. Despite the virtually unlimited number of potential sources among bacterial strains, the number of useable compounds within this promising class of adjuvants are few. We have developed bacterial enzymatic combinatorial chemistry (BECC as a method to generate rationally designed, functionally diverse lipid A. BECC removes endogenous or introduces exogenous lipid A-modifying enzymes to bacteria, effectively reprogramming the lipid A biosynthetic pathway. In this study, BECC is applied within an avirulent strain of Yersinia pestis to develop structurally distinct LOS molecules that elicit differential Toll-like receptor 4 (TLR4 activation. Using reporter cell lines that measure NF-κB activation, BECC-derived molecules were screened for the ability to induce a lower proinflammatory response than Escherichia coli LOS. Their structures exhibit varied, dose-dependent, TLR4-driven NF-κB activation with both human and mouse TLR4 complexes. Additional cytokine secretion screening identified molecules that induce levels of tumor necrosis factor alpha (TNF-α and interleukin-8 (IL-8 comparable to the levels induced by phosphorylated hexa-acyl disaccharide (PHAD. The lead candidates demonstrated potent immunostimulation in mouse splenocytes, human primary blood mononuclear cells (PBMCs, and human monocyte-derived dendritic cells (DCs. This newly described system allows directed programming of lipid A synthesis and has the potential to generate a diverse array of TLR4 agonist candidates.

  14. Consumption of Bifidobacterium animalis subsp. lactis BB-12 in yogurt reduced expression of TLR-2 on peripheral blood-derived monocytes and pro-inflammatory cytokine secretion in young adults.

    Science.gov (United States)

    Meng, Huicui; Ba, Zhaoyong; Lee, Yujin; Peng, Jiayu; Lin, Junli; Fleming, Jennifer A; Furumoto, Emily J; Roberts, Robert F; Kris-Etherton, Penny M; Rogers, Connie J

    2017-03-01

    Probiotic bacteria modulate immune parameters and inflammatory outcomes. Emerging evidence demonstrates that the matrix used to deliver probiotics may influence the efficacy of probiotic interventions in vivo. The aims of the current study were to evaluate (1) the effect of one species, Bifidobacterium animalis subsp. lactis BB-12 at a dose of log10 ± 0.5 CFUs/day on immune responses in a randomized, partially blinded, 4-period crossover, free-living study, and (2) whether the immune response to BB-12 differed depending on the delivery matrix. Healthy adults (n = 30) aged 18-40 years were recruited and received four treatments in a random order: (A) yogurt smoothie alone; smoothie with BB-12 added (B) before or (C) after yogurt fermentation, or (D) BB-12 given in capsule form. At baseline and after each 4-week treatment, peripheral blood mononuclear cells (PBMCs) were isolated, and functional and phenotypic marker expression was assessed. BB-12 interacted with peripheral myeloid cells via Toll-like receptor 2 (TLR-2). The percentage of CD14 + HLA-DR + cells in peripheral blood was increased in male participants by all yogurt-containing treatments compared to baseline (p = 0.0356). Participants who consumed yogurt smoothie with BB-12 added post-fermentation had significantly lower expression of TLR-2 on CD14 + HLA-DR + cells (p = 0.0186) and reduction in TNF-α secretion from BB-12- (p = 0.0490) or LPS-stimulated (p = 0.0387) PBMCs compared to baseline. These findings not only demonstrate a potential anti-inflammatory effect of BB-12 in healthy adults, but also indicate that the delivery matrix influences the immunomodulatory properties of BB-12.

  15. Enhanced Dendritic Cell-Mediated Antigen-Specific CD4+ T Cell Responses: IFN-Gamma Aids TLR Stimulation

    Directory of Open Access Journals (Sweden)

    Kuo-Ching Sheng

    2013-01-01

    Full Text Available Phenotypic maturation and T cell stimulation are two functional attributes of DCs critical for immune induction. The combination of antigens, including those from cancer, with Toll-like receptor (TLR ligands induces far superior cellular immune responses compared to antigen alone. In this study, IFN-gamma treatment of bone marrow-derived DC, followed by incubation with the TLR2, TLR4, or TLR9 agonists, enhanced DC activation compared to TLR ligation alone. Most notably, the upregulation of CD40 with LPS stimulation and CD86 with CpG stimulation was observed in in vitro cultures. Similarly, IFN-gamma coinjected with TLR ligands was able to promote DC activation in vivo, with DCs migrating from the site of immunization to the popliteal lymph nodes demonstrating increased expression of CD80 and CD86. The heightened DC activation translated to a drastic increase in T cell stimulatory capacity in both antigen independent and antigen dependent fashions. This is the first time that IFN-gamma has been shown to have a combined effect with TLR ligation to enhance DC activation and function. The results demonstrate the novel use of IFN-gamma together with TLR agonists to enhance antigen-specific T cell responses, for applications in the development of enhanced vaccines and drug targets against diseases including cancer.

  16. Nonbilayer Phospholipid Arrangements Are Toll-Like Receptor-2/6 and TLR-4 Agonists and Trigger Inflammation in a Mouse Model Resembling Human Lupus

    Directory of Open Access Journals (Sweden)

    Carlos Wong-Baeza

    2015-01-01

    Full Text Available Systemic lupus erythematosus is characterized by dysregulated activation of T and B cells and autoantibodies to nuclear antigens and, in some cases, lipid antigens. Liposomes with nonbilayer phospholipid arrangements induce a disease resembling human lupus in mice, including IgM and IgG antibodies against nonbilayer phospholipid arrangements. As the effect of these liposomes on the innate immune response is unknown and innate immune system activation is necessary for efficient antibody formation, we evaluated the effect of these liposomes on Toll-like receptor (TLR signaling, cytokine production, proinflammatory gene expression, and T, NKT, dendritic, and B cells. Liposomes induce TLR-4- and, to a lesser extent, TLR-2/TLR-6-dependent signaling in TLR-expressing human embryonic kidney (HEK cells and bone marrow-derived macrophages. Mice with the lupus-like disease had increased serum concentrations of proinflammatory cytokines, C3a and C5a; they also had more TLR-4-expressing splenocytes, a higher expression of genes associated with TRIF-dependent TLR-4-signaling and complement activation, and a lower expression of apoptosis-related genes, compared to healthy mice. The percentage of NKT and the percentage and activation of dendritic and B2 cells were also increased. Thus, TLR-4 and TLR-2/TLR-6 activation by nonbilayer phospholipid arrangements triggers an inflammatory response that could contribute to autoantibody production and the generation of a lupus-like disease in mice.

  17. Effects of Mushroom and Herb Polysaccharides on Cellular and Humoral Immune Responses of Eimeria tenella-Infected Chickens

    NARCIS (Netherlands)

    Guo, F.C.; Kwakkel, R.P.; Williams, B.A.; Parmentier, H.K.; Li, W.K.; Yang, Z.Q.; Verstegen, M.W.A.

    2004-01-01

    We investigated the effects of polysaccharide extracts from 2 mushrooms, Lentinus edodes (LenE) and Tremella fuciformis (TreE), and an herb, Astragalus membranaceus (AstE), on cellular and humoral immune responses of Eimeria tenella-infected chickens. A total of 150 broiler chicks were assigned to 5

  18. Coccidiosis Immunization: Effects of Mushroom and Herb Polysaccharides on Immune Responses of Chickens Infected with Eimeria Tenella

    NARCIS (Netherlands)

    Guo, F.C.; Kwakkel, R.P.; Williams, B.A.; Suo, X.; Li, W.K.; Verstegen, M.W.A.

    2005-01-01

    An experiment was conducted to investigate the effects of polysaccharide extracts (E) of two mushrooms, Lentinus edodes (LenE) and Tremella fuciformis (TreE), and an herb, Astragalus membranaceus (AstE), on the immune responses of chickens infected with Eimeria tenella. A total of 180 broiler

  19. Location of RAD51-like protein during meiotic prophase in Eimeria tenella.

    Science.gov (United States)

    Del Cacho, Emilio; Gallego, Margarita; Pagés, Marc; Barbero, José Luís; Monteagudo, Luís; Sánchez-Acedo, Caridad

    2011-05-31

    This study focuses on reporting events in Eimeria tenella oocysts from early to late prophase I in terms of RAD51 protein in association with the synaptonemal complex formed between homologous chromosomes. The aim of the study was the sequential localization of RAD51 protein, which is involved in the repair of double-strand breaks (DSBs) on the eimerian chromosomes as they synapse and desynapse. Structural Maintenance of Chromosome protein SMC3, which plays a role in synaptonemal complex formation, was labeled to identify initiation and progress of chromosome synapsis and desynapsis in parallel with the appearance and disappearance of RAD51 foci. Antibodies directed against RAD51 and cohesin subunit SMC3 proteins were labeled with either fluorescence or colloidal gold to visualize RAD51 protein foci and synaptonemal complexes. RAD51 protein localization during prophase I was studied on meiotic chromosomes spreads obtained from oocysts at different points in time after the start of sporulation. The present findings showed that foci detected with the antibody directed against RAD51 protein first appeared at the pre-leptotene stage before homologous chromosomes began pairing. Subsequently, the foci were detected in association with the lateral elements at the precise sites where synapsis were in progress. These findings lead us to suggest that in E. tenella, homologous chromosome pairing was a DSB-dependent mechanism and reinforced the participation of RAD51 protein in meiotic homology search, alignment and pairing of chromosomes. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Anticoccidial efficacy testing: In vitro Eimeria tenella assays as replacement for animal experiments.

    Science.gov (United States)

    Thabet, Ahmed; Zhang, Runhui; Alnassan, Alaa-Aldin; Daugschies, Arwid; Bangoura, Berit

    2017-01-15

    Availability of an accurate in vitro assay is a crucial demand to determine sensitivity of Eimeria spp. field strains toward anticoccidials routinely. In this study we tested in vitro models of Eimeria tenella using various polyether ionophores (monensin, salinomycin, maduramicin, and lasalocid) and toltrazuril. Minimum inhibitory concentrations (MIC 95 , MIC 50/95 ) for the tested anticoccidials were defined based on a susceptible reference (Houghton strain), Ref-1. In vitro sporozoite invasion inhibition assay (SIA) and reproduction inhibition assay (RIA) were applied on sensitive laboratory (Ref-1 and Ref-2) and field (FS-1, FS-2, and FS-3) strains to calculate percent of inhibition under exposure of these strains to the various anticoccidials (%I SIA and%I RIA, respectively). The in vitro data were related to oocyst excretion, lesion scores, performance, and global resistance indices (GI) assessed in experimentally infected chickens. Polyether ionophores applied in the RIA were highly effective at MIC 95 against Ref-1 and Ref-2 (%I RIA ≥95%). In contrast, all tested field strains displayed reduced to low efficacy (%I RIA animal model (p89%) against all strains used in this study. However, adjusted GI (GI adj ) for toltrazuril-treated groups exhibited differences between reference and field strains which might indicate varying sensitivity. RIA is a suitable in vitro tool to detect sensitivity of E. tenella towards polyether ionophores, and may thus help to reduce, replace, or refine use of animal experimentation for in vivo sensitivity assays. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Evaluation of plasma chemistry and haematological studies on chickens infected with Eimeria tenella and E acervulina.

    Science.gov (United States)

    Fukata, T; Komba, Y; Sasai, K; Baba, E; Arakawa, A

    1997-07-12

    Plasma chemistry and haematological studies were conducted on chickens with coccidiosis. Male White Leghorn chickens, of two weeks old, were inoculated with 5 x 10(4) Eimeria tenella sporulated oocysts or with 1 x 10(6) E acervulina sporulated oocysts. Blood samples were taken four, seven and 11 days after inoculation. A wet chemistry system was applied to measure the plasma activities of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma glutamyltransferase, creatine kinase, amylase and lactate dehydrogenase and the concentrations of creatine, total bilirubin, urate, total cholesterol, total protein, albumin, glucose and triglycerides. A dry chemistry system was applied to measure sodium, potassium, chloride and calcium. The number of red blood cells and packed cell volume were determined by a micro cell counter and blood pH was measured with a blood gas analyser. The erythrocyte count, packed cell volume, sodium and chloride levels in the chickens infected with E tenella were significantly (P < 0.05) lower than those of the uninfected controls. The significant decrease in blood pH of the chickens infected with E acervulina suggests malabsorption associated with duodenal lesions induced by the infection.

  2. Retinal astrocytes pretreated with NOD2 and TLR2 ligands activate uveitogenic T cells.

    Directory of Open Access Journals (Sweden)

    Guomin Jiang

    Full Text Available On entering the tissues, infiltrating autoreactive T cells must be reactivated locally to gain pathogenic activity. We have previously reported that, when activated by Toll-like receptor 3 (TLR3 and TLR4 ligands, retinal astrocytes (RACs are able to function as antigen-presenting cells to re-activate uveitogenic T cells and allow responder T cells to induce uveitis in mice. In the present study, we found that, although the triggering of TLR2 or nucleotide-binding oligomerization domain receptor 2 (NOD2 alone did not activate RACs, their combined triggering induced RACs with the phenotypes required to efficiently re-activate interphotoreceptor retinoid-binding protein (IRBP-specific T cells. The synergistic effect of TLR2 and NOD2 ligands on RAC activation might be explained by the observations that bacterial lipoprotein (BLP, a TLR2 ligand was able to upregulate NOD2 expression and the combination of BLP and muramyldipeptide (MDP, a NOD2 ligand enhanced the expression of RICK (Rip2, the signaling molecule of NOD2. Moreover, the synergistic effect of MDP and BLP on RACs was lost when the RACs were derived from NOD2 knockout mice or were pre-treated with Rip2 antagonist. Thus, our data suggest that exogenous or endogenous molecules acting on both TLR2 and NOD2 on RACs might have an enhancing effect on susceptibility to autoimmune uveitis.

  3. Regulation of intestinal immune responses through TLR activation: implications for pro- and prebiotics

    Directory of Open Access Journals (Sweden)

    Sander eDe Kivit

    2014-02-01

    Full Text Available The intestinal mucosa is constantly facing a high load of antigens including bacterial antigens derived from the microbiota and food. Despite this, the immune cells present in the gastrointestinal tract do not initiate a pro-inflammatory immune response. Toll-like receptors (TLRs are pattern recognition receptors expressed by various cells in the gastrointestinal tract, including intestinal epithelial cells (IEC and resident immune cells in the lamina propria. Many diseases, including chronic intestinal inflammation (e.g. inflammatory bowel disease, irritable bowel syndrome (IBS, allergic gastroenteritis (e.g. eosinophilic gastroenteritis and allergic IBS and infections are nowadays associated with a deregulated microbiota. The microbiota may directly interact with TLR. In addition, differences in intestinal TLR expression in health and disease may suggest that TLR play an essential role in disease pathogenesis and may be novel targets for therapy. TLR signaling in the gut is involved in either maintaining intestinal homeostasis or the induction of an inflammatory response. This mini review provides an overview of the current knowledge regarding the contribution of intestinal epithelial TLR signaling in both tolerance induction or promoting intestinal inflammation, with a focus on food allergy. We will also highlight a potential role of the microbiota in regulating gut immune responses, especially through TLR activation.

  4. Telomere-mediated chromosomal instability triggers TLR4 induced inflammation and death in mice.

    Directory of Open Access Journals (Sweden)

    Rabindra N Bhattacharjee

    Full Text Available BACKGROUND: Telomeres are essential to maintain chromosomal stability. Cells derived from mice lacking telomerase RNA component (mTERC-/- mice display elevated telomere-mediated chromosome instability. Age-dependent telomere shortening and associated chromosome instability reduce the capacity to respond to cellular stress occurring during inflammation and cancer. Inflammation is one of the important risk factors in cancer progression. Controlled innate immune responses mediated by Toll-like receptors (TLR are required for host defense against infection. Our aim was to understand the role of chromosome/genome instability in the initiation and maintenance of inflammation. METHODOLOGY/PRINCIPAL FINDINGS: We examined the function of TLR4 in telomerase deficient mTERC-/- mice harbouring chromosome instability which did not develop any overt immunological disorder in pathogen-free condition or any form of cancers at this stage. Chromosome instability was measured in metaphase spreads prepared from wildtype (mTERC+/+, mTERC+/- and mTERC-/- mouse splenocytes. Peritoneal and/or bone marrow-derived macrophages were used to examine the responses of TLR4 by their ability to produce inflammatory mediators TNFalpha and IL6. Our results demonstrate that TLR4 is highly up-regulated in the immune cells derived from telomerase-null (mTERC-/- mice and lipopolysaccharide, a natural ligand for TLR4 stabilises NF-kappaB binding to its promoter by down-regulating ATF-3 in mTERC-/- macrophages. CONCLUSIONS/SIGNIFICANCE: Our findings implied that background chromosome instability in the cellular level stabilises the action of TLR4-induced NF-kappaB action and sensitises cells to produce excess pro-inflammatory mediators. Chromosome/genomic instability data raises optimism for controlling inflammation by non-toxic TLR antagonists among high-risk groups.

  5. A Role for TLR4 in Clostridium difficile Infection and the Recognition of Surface Layer Proteins.

    LENUS (Irish Health Repository)

    Ryan, Anthony

    2011-06-01

    Clostridium difficile is the etiological agent of antibiotic-associated diarrhoea (AAD) and pseudomembranous colitis in humans. The role of the surface layer proteins (SLPs) in this disease has not yet been fully explored. The aim of this study was to investigate a role for SLPs in the recognition of C. difficile and the subsequent activation of the immune system. Bone marrow derived dendritic cells (DCs) exposed to SLPs were assessed for production of inflammatory cytokines, expression of cell surface markers and their ability to generate T helper (Th) cell responses. DCs isolated from C3H\\/HeN and C3H\\/HeJ mice were used in order to examine whether SLPs are recognised by TLR4. The role of TLR4 in infection was examined in TLR4-deficient mice. SLPs induced maturation of DCs characterised by production of IL-12, TNFα and IL-10 and expression of MHC class II, CD40, CD80 and CD86. Furthermore, SLP-activated DCs generated Th cells producing IFNγ and IL-17. SLPs were unable to activate DCs isolated from TLR4-mutant C3H\\/HeJ mice and failed to induce a subsequent Th cell response. TLR4(-\\/-) and Myd88(-\\/-), but not TRIF(-\\/-) mice were more susceptible than wild-type mice to C. difficile infection. Furthermore, SLPs activated NFκB, but not IRF3, downstream of TLR4. Our results indicate that SLPs isolated from C. difficile can activate innate and adaptive immunity and that these effects are mediated by TLR4, with TLR4 having a functional role in experimental C. difficile infection. This suggests an important role for SLPs in the recognition of C. difficile by the immune system.

  6. Induction of protective immunity against Eimeria tenella, Eimeria necatrix, Eimeria maxima and Eimeria acervulina infections using multivalent epitope DNA vaccines.

    Science.gov (United States)

    Song, Xiaokai; Ren, Zhe; Yan, Ruofeng; Xu, Lixin; Li, Xiangrui

    2015-06-04

    Avian coccidiosis is mostly caused by mixed infection of several Eimeria species under natural conditions and immunity to avian coccidiosis is largely dependent on T-cell immune response. In this study, 14 T-cell epitope fragments from eight antigens of Eimeria tenella (E. tenella), Eimeria necatrix (E. necatrix), Eimeria maxima (E. maxima) and Eimeria acervulina (E. acervulina) were ligated with pVAX1 producing 14 monovalent DNA vaccines, respectively. Protective immunity of the monovalent DNA vaccines was assessed by in vivo challenge experiments and then four most protective fragments of each species were chosen to construct multivalent epitope DNA vaccines with or without chicken IL-2 as genetic adjuvant. Protective efficacies of the epitope DNA vaccines on chickens against E. tenella, E. necatrix, E. maxima and E. acervulina were evaluated. The results showed that the constructed multivalent epitope DNA vaccines significantly increased body weight gain, alleviated enteric lesions and reduced oocyst output of the infected birds. Especially, the multivalent epitope DNA vaccines of pVAX1-NA4-1-TA4-1-LDH-2-EMCDPK-1 and pVAX1-NA4-1-TA4-1-LDH-2-EMCDPK-1-IL-2 not only significantly increased body weight gain, alleviated enteric lesions and reduced oocyst output of the infected birds, but also resulted in anti-coccidial index (ACI) more than 170 against E. tenella, E. necatrix, E. maxima and E. acervulina, which indicated they could induce protective immunity against E. tenella, E. necatrix, E. maxima and E. acervulina. Our findings suggest the constructed multivalent epitope DNA vaccines are the potential candidate multivalent vaccines against mixed infection of Eimeria. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Association analysis identifies TLR7 and TLR8 as novel risk genes in asthma and related disorders

    DEFF Research Database (Denmark)

    Møller-Larsen, Steffen; Nyegaard, Mette; Haagerup, Annette

    2008-01-01

    the TLR7 and TLR8 genes. METHODS: We investigated the involvement of TLR7 and TLR8 in the aetiology of asthma and related disorders by a family based association analysis of two independently ascertained family samples comprising 540 and 424 individuals from 135 and 100 families, respectively. Ten...

  8. Molecular characterization and analysis of a novel protein disulfide isomerase-like protein of Eimeria tenella.

    Science.gov (United States)

    Han, Hongyu; Dong, Hui; Zhu, Shunhai; Zhao, Qiping; Jiang, Lianlian; Wang, Yange; Li, Liujia; Wu, Youlin; Huang, Bing

    2014-01-01

    Protein disulfide isomerase (PDI) and PDI-like proteins are members of the thioredoxin superfamily. They contain thioredoxin-like domains and catalyze the physiological oxidation, reduction and isomerization of protein disulfide bonds, which are involved in cell function and development in prokaryotes and eukaryotes. In this study, EtPDIL, a novel PDI-like gene of Eimeria tenella, was cloned using rapid amplification of cDNA ends (RACE) according to the expressed sequence tag (EST). The EtPDIL cDNA contained 1129 nucleotides encoding 216 amino acids. The deduced EtPDIL protein belonged to thioredoxin-like superfamily and had a single predicted thioredoxin domain with a non-classical thioredoxin-like motif (SXXC). BLAST analysis showed that the EtPDIL protein was 55-59% identical to PDI-like proteins of other apicomplexan parasites. The transcript and protein levels of EtPDIL at different development stages were investigated by real-time quantitative PCR and western blot. The messenger RNA and protein levels of EtPDIL were higher in sporulated oocysts than in unsporulated oocysts, sporozoites or merozoites. Protein expression was barely detectable in unsporulated oocysts. Western blots showed that rabbit antiserum against recombinant EtPDIL recognized only a native 24 kDa protein from parasites. Immunolocalization with EtPDIL antibody showed that EtPDIL had a disperse distribution in the cytoplasm of whole sporozoites and merozoites. After sporozoites were incubated in complete medium, EtPDIL protein concentrated at the anterior of the sporozoites and appeared on the surface of parasites. Specific staining was more intense and mainly located on the parasite surface after merozoites released from mature schizonts invaded DF-1 cells. After development of parasites in DF-1 cells, staining intensified in trophozoites, immature schizonts and mature schizonts. Antibody inhibition of EtPDIL function reduced the ability of E. tenella to invade DF-1 cells. These results

  9. Insights into the genome structure and copy-number variation of Eimeria tenella

    Directory of Open Access Journals (Sweden)

    Lim Lik-Sin

    2012-08-01

    Full Text Available Abstract Background Eimeria is a genus of parasites in the same phylum (Apicomplexa as human parasites such as Toxoplasma, Cryptosporidium and the malaria parasite Plasmodium. As an apicomplexan whose life-cycle involves a single host, Eimeria is a convenient model for understanding this group of organisms. Although the genomes of the Apicomplexa are diverse, that of Eimeria is unique in being composed of large alternating blocks of sequence with very different characteristics - an arrangement seen in no other organism. This arrangement has impeded efforts to fully sequence the genome of Eimeria, which remains the last of the major apicomplexans to be fully analyzed. In order to increase the value of the genome sequence data and aid in the effort to gain a better understanding of the Eimeria tenella genome, we constructed a whole genome map for the parasite. Results A total of 1245 contigs representing 70.0% of the whole genome assembly sequences (Wellcome Trust Sanger Institute were selected and subjected to marker selection. Subsequently, 2482 HAPPY markers were developed and typed. Of these, 795 were considered as usable markers, and utilized in the construction of a HAPPY map. Markers developed from chromosomally-assigned genes were then integrated into the HAPPY map and this aided the assignment of a number of linkage groups to their respective chromosomes. BAC-end sequences and contigs from whole genome sequencing were also integrated to improve and validate the HAPPY map. This resulted in an integrated HAPPY map consisting of 60 linkage groups that covers approximately half of the estimated 60 Mb genome. Further analysis suggests that the segmental organization first seen in Chromosome 1 is present throughout the genome, with repeat-poor (P regions alternating with repeat-rich (R regions. Evidence of copy-number variation between strains was also uncovered. Conclusions This paper describes the application of a whole genome mapping

  10. Molecular characterization and analysis of a novel protein disulfide isomerase-like protein of Eimeria tenella.

    Directory of Open Access Journals (Sweden)

    Hongyu Han

    Full Text Available Protein disulfide isomerase (PDI and PDI-like proteins are members of the thioredoxin superfamily. They contain thioredoxin-like domains and catalyze the physiological oxidation, reduction and isomerization of protein disulfide bonds, which are involved in cell function and development in prokaryotes and eukaryotes. In this study, EtPDIL, a novel PDI-like gene of Eimeria tenella, was cloned using rapid amplification of cDNA ends (RACE according to the expressed sequence tag (EST. The EtPDIL cDNA contained 1129 nucleotides encoding 216 amino acids. The deduced EtPDIL protein belonged to thioredoxin-like superfamily and had a single predicted thioredoxin domain with a non-classical thioredoxin-like motif (SXXC. BLAST analysis showed that the EtPDIL protein was 55-59% identical to PDI-like proteins of other apicomplexan parasites. The transcript and protein levels of EtPDIL at different development stages were investigated by real-time quantitative PCR and western blot. The messenger RNA and protein levels of EtPDIL were higher in sporulated oocysts than in unsporulated oocysts, sporozoites or merozoites. Protein expression was barely detectable in unsporulated oocysts. Western blots showed that rabbit antiserum against recombinant EtPDIL recognized only a native 24 kDa protein from parasites. Immunolocalization with EtPDIL antibody showed that EtPDIL had a disperse distribution in the cytoplasm of whole sporozoites and merozoites. After sporozoites were incubated in complete medium, EtPDIL protein concentrated at the anterior of the sporozoites and appeared on the surface of parasites. Specific staining was more intense and mainly located on the parasite surface after merozoites released from mature schizonts invaded DF-1 cells. After development of parasites in DF-1 cells, staining intensified in trophozoites, immature schizonts and mature schizonts. Antibody inhibition of EtPDIL function reduced the ability of E. tenella to invade DF-1 cells

  11. Streptococci Engage TLR13 on Myeloid Cells in a Site-Specific Fashion.

    Science.gov (United States)

    Kolter, Julia; Feuerstein, Reinhild; Spoeri, Evelyne; Gharun, Kourosh; Elling, Roland; Trieu-Cuot, Patrick; Goldmann, Tobias; Waskow, Claudia; Chen, Zhijian J; Kirschning, Carsten J; Deshmukh, Sachin D; Henneke, Philipp

    2016-03-15

    Streptococci are common human colonizers with a species-specific mucocutaneous distribution. At the same time, they are among the most important and most virulent invasive bacterial pathogens. Thus, site-specific cellular innate immunity, which is predominantly executed by resident and invading myeloid cells, has to be adapted with respect to streptococcal sensing, handling, and response. In this article, we show that TLR13 is the critical mouse macrophage (MΦ) receptor in the response to group B Streptococcus, both in bone marrow-derived MΦs and in mature tissue MΦs, such as those residing in the lamina propria of the colon and the dermis, as well as in microglia. In contrast, TLR13 and its chaperone UNC-93B are dispensable for a potent cytokine response of blood monocytes to group B Streptococcus, although monocytes serve as the key progenitors of intestinal and dermal MΦs. Furthermore, a specific role for TLR13 with respect to MΦ function is supported by the response to staphylococci, where TLR13 and UNC-93B limit the cytokine response in bone marrow-derived MΦs and microglia, but not in dermal MΦs. In summary, TLR13 is a critical and site-specific receptor in the single MΦ response to β-hemolytic streptococci. Copyright © 2016 by The American Association of Immunologists, Inc.

  12. Cholesterol Oxidase Binds TLR2 and Modulates Functional Responses of Human Macrophages

    Directory of Open Access Journals (Sweden)

    Katarzyna Bednarska

    2014-01-01

    Full Text Available Cholesterol oxidase (ChoD is considered to be an important virulence factor for Mycobacterium tuberculosis (Mtb, but its influence on macrophage activity is unknown. Here we used Nocardia erythropolis ChoD, which is very similar to the Mtb enzyme (70% identity at the amino-acid level, to evaluate the impact of bacterial ChoD on the activity of THP-1-derived macrophages in vitro. We found that ChoD decreased the surface expression of Toll-like receptor type 2 (TLR2 and complement receptor 3 (CR3 on these macrophages. Flow cytometry and confocal microscopy showed that ChoD competed with lipoteichoic acid for ligand binding sites on TLR2 but not on CR3, suggesting that ChoD signaling is mediated via TLR2. Binding of ChoD to the membrane of macrophages had diverse effects on the activity of macrophages, activating p38 mitogen activated kinase and stimulating production of a large amount of interleukin-10. Moreover, ChoD primed macrophages to enhance the production of reactive oxygen species in response to the phorbol myristate acetate, which was reduced by “switching off” TLR-derived signaling through interleukin-1 receptor-associated kinases 1 and 4 inhibition. Our study revealed that ChoD interacts directly with macrophages via TLR2 and influences the biological activity of macrophages during the development of the initial response to infection.

  13. Identification, characterization and genetic mapping of TLR7, TLR8a1 and TLR8a2 genes in rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Palti, Yniv; Gahr, Scott A.; Purcell, Maureen K.; Hadidi, Sima; Rexroad, Caird E.; Wiens, Gregory A.

    2010-01-01

    Induction of the innate immune pathways is critical for early anti-viral defense but there is limited understanding of how teleost fish recognize viral molecules and activate these pathways. In mammals, Toll-like receptors (TLR) 7 and 8 bind single-stranded RNA of viral origin and are activated by synthetic anti-viral imidazoquinoline compounds. Herein, we identify and describe the rainbow trout (Oncorhynchus mykiss) TLR7 and TLR8 gene orthologs and their mRNA expression. Two TLR7/8 loci were identified from a rainbow trout bacterial artificial chromosome (BAC) library using DNA fingerprinting and genetic linkage analyses. Direct sequencing of two representative BACs revealed intact omTLR7 and omTLR8a1 open reading frames (ORFs) located on chromosome 3 and a second locus on chromosome 22 that contains an omTLR8a2 ORF and a putative TLR7 pseudogene. We used the omTLR8a1/2 nomenclature for the two trout TLR8 genes as phylogenetic analysis revealed that they and all the other teleost TLR8 genes sequenced to date are similar to the zebrafish TLR8a, but are distinct from the zebrafish TLR8b. The duplicated trout loci exhibit conserved synteny with other fish genomes extending beyond the tandem of TLR7/8 genes. The trout TLR7 and 8a1/2 genes are composed of a single large exon similar to all other described TLR7/8 genes. The omTLR7 ORF is predicted to encode a 1049 amino acid (aa) protein with 84% similarity to the Fugu TLR7 and a conserved pattern of predicted leucine-rich repeats (LRR). The omTLR8a1 and omTLR8a2 are predicted to encode 1035- and 1034-aa proteins, respectively, and have 86% similarity to each other. omTLR8a1 is likely the ortholog of the only Atlantic salmon TLR8 gene described to date as they have 95% aa sequence similarity. The tissue expression profiles of omTLR7, omTLR8a1 and omTLR8a2 in healthy trout were highest in spleen tissue followed by anterior and then posterior kidney tissues. Rainbow trout anterior kidney leukocytes produced elevated

  14. Molecular and functional characterization of Toll-like receptor (Tlr)1 and Tlr2 in common carp (Cyprinus carpio).

    Science.gov (United States)

    Fink, Inge R; Pietretti, Danilo; Voogdt, Carlos G P; Westphal, Adrie H; Savelkoul, Huub F J; Forlenza, Maria; Wiegertjes, Geert F

    2016-09-01

    Toll-like receptors (TLRs) are fundamental components of innate immunity that play significant roles in the defence against pathogen invasion. In this study, we present the molecular characterization of the full-length coding sequence of tlr1, tlr2a and tlr2b from common carp (Cyprinus carpio). Each is encoded within a single exon and contains a conserved number of leucine-rich repeats, a transmembrane region and an intracellular TIR domain for signalling. Indeed, sequence, phylogenetic and synteny analysis of carp tlr1, tlr2a and tlr2b support that these genes are orthologues of mammalian TLR1 and TLR2. The tlr genes are expressed in various immune organs and cell types. Furthermore, the carp sequences exhibited a good three-dimensional fit with the heterodimer structure of human TLR1-TLR2, including the potential to bind to the ligand Pam3CSK4. This supports the possible formation of carp Tlr1-Tlr2 heterodimers. However, we were unable to demonstrate Tlr1/Tlr2-mediated ligand binding in transfected cell lines through NF-κB activation, despite showing the expression and co-localization of Tlr1 and Tlr2. We discuss possible limitations when studying ligand-specific activation of NF-κB after expression of Tlr1 and/or Tlr2 in human but also fish cell lines and we propose alternative future strategies for studying ligand-binding properties of fish Tlrs. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Studies on the effects of whole-body gamma irradiation on chickens infected with Eimeria tenella

    International Nuclear Information System (INIS)

    Merritt, S.V.

    1974-01-01

    Whole-body exposure of one- and three-week-old White Leghorn cockerels to 600 R gamma radiation (Cesium-137) 24 hours before oral inoculation with 500, 2500, 5000, or 50,000 Eimeria tenella oocysts produced a pattern of mortality differing markedly from nonirradiated, infected (NRI) control birds. When oocyst dosage was held constant (2500) and radiation exposure increased (250, 450, 600, 800, or 1000 R) a gradual increase in mortality rate with higher radiation dosages was observed among both one- and three-week-old birds. Birds irradiated 24 hours or more before inoculation were less able to survive infection than were those irradiated one hour before and one, two, three, or four days after inoculation. (U.S.)

  16. Expression and immunological characterisation of Eimeria tenella glycosylphosphatidylinositol-anchored surface antigen-5

    Science.gov (United States)

    Ho, Sue-Kim; Nathan, Sheila; Wan, Kiew-Lian

    2016-11-01

    Eimeria tenella is the most pathogenic of the Eimeria species that infect chickens and causes huge economic losses to the poultry industry. The glycosylphosphatidylinositol-anchored surface antigen-5 (SAG5) found on the surface of the parasite has been shown to activate the chicken's immune system. In this study, recombinant SAG5 was expressed, purified and used to investigate the immune-inducing characteristics of the molecule. Chickens were immunized with purified recombinant SAG5 and sera were subjected to Enzyme-linked Immunosorbant Assay (ELISA). Results indicated that specific antibodies against rSAG5 were produced, with IgG detected at a higher level compared to IgA and IgM. Information on the immunological responses elicited by SAG5 provides essential knowledge that will contribute towards the effort to develop more effective strategies against coccidiosis.

  17. Irradiated Eimeria brunetti, E. necatrix and E. tenella in the simultaneous immunization of chickens

    International Nuclear Information System (INIS)

    Sokolic, A.; Movsesijan, M.; Tanielian, Z.; Abu Ali, N.

    1976-01-01

    Chickens three weeks of age were immunized simultaneously against E. necatrix, E. tenella and E. brunetti receiving a single oral dose of oocysts of these Eimeria spp. irradiated at 10k rads with gamma rays delivered from a 60 Co-source. Two weeks later immunized chickens and their corresponding untreated controls were challenged with infective oocysts of the same three protozoan species. The results obtained have shown that all immunized chickens survived a heavy challenge which killed 70% of the corresponding control chickens. The results and their possible practical implication are discussed. Eimeria spp. selected for these studies were of great epidemiological and economic importance in the area of Lebanon with the most intensive poultry production. (author)

  18. In vitro evaluation of the disinfection efficacy on Eimeria tenella unsporulated oocysts isolated from broilers.

    Science.gov (United States)

    Guimarães, José S; Bogado, Alexey L Gomel; da Cunha, Thiago Cezar B; Garcia, João Luis

    2007-01-01

    The objective of this study was to evaluate in vitro the action of eight chemical principles by disinfection efficacy (DE) of Eimeria tenella oocysts. Disinfection efficacy was evaluated by either destruction or sporulation inhibition of the oocysts. Eight treatments were performed: T1 (Glutaraldehyde 42.5 g + Benzalkonium Chloride 7.5 g); T2 (Benzalkonium chloride + quaternary ammonium salt); T3 (formol 37% + Sodium Dodecylbenzene Sulfonate 12%); T4 (sodium hypochlorite 2%); T5 (Orthodichlorobenzene 60% + Xylene 30%); T6 (Polyoctyl polyamino ethyl glycine + Polyoxyethylene alkylphenol ether + Sodium Chloride); T7 (Chloramine T) and finally T8 (free iodine 2.25% + Phosphoric acid 15 g). The control test was carried out with distilled water (T9). The best DE were observed, respectively, in T3 (79.49%), T5 (75.60%) and T4 (65.56%) treatments.

  19. TLR2 and TLR9 synergistically control herpes simplex virus infection in the brain

    DEFF Research Database (Denmark)

    Sørensen, Louise N; Reinert, Line S; Malmgaard, Lene

    2008-01-01

    toward HSV-2 infection. After a systemic infection, the cytokine serum response was markedly reduced in the double knockout mice, but only partly affected in either strain of the single knockout mice. This was supported by in vitro data showing that HSV-induced cytokine expression relayed on TLR2 and TLR...... stimulate innate antiviral activities, thereby protecting against HSV infection in the brain....

  20. TLR2 and TLR9 Synergistically Control Herpes Simplex Virus Infection in the Brain

    DEFF Research Database (Denmark)

    Sørensen, Louise Nørgaard; Reinert, Line; Malmgaard, Lene

    2008-01-01

    Viruses are recognized by the innate immune system through pattern recognition receptors (PRRs). For instance, HSV virions and genomic DNA are recognized by TLR2 and TLR9, respectively. Although several viruses and viral components have been shown to stimulate cells through TLRs, only very few st...

  1. A genetic linkage map for the apicomplexan protozoan parasite Eimeria maxima and comparison with Eimeria tenella.

    Science.gov (United States)

    Blake, Damer P; Oakes, Richard; Smith, Adrian L

    2011-02-01

    Eimeria maxima is one of the seven Eimeria spp. that infect the chicken and cause the disease coccidiosis. The well characterised immunogenicity and genetic diversity associated with E. maxima promote its use in genetics-led studies on avian coccidiosis. The development of a genetic map for E. maxima, presented here based upon 647 amplified fragment length polymorphism markers typed from 22 clonal hybrid lines and assembled into 13 major linkage groups, is a major new resource for work with this parasite. Comparison with genetic maps produced for other coccidial parasites indicates relatively high levels of genetic recombination. Conversion of ∼14% of the markers representing the major linkage groups to sequence characterised amplified region markers can provide a scaffold for the assembly of future genomic sequences as well as providing a foundation for more detailed genetic maps. Comparison with the Eimeria tenella genetic map produced 10years ago has revealed a less biased marker distribution, with no more than nine markers mapped within any unresolved heritable unit. Nonetheless, preliminary bioinformatic characterisation of the three largest publicly available genomic E. maxima sequences suggest that the feature-poor/feature-rich structure which has previously been found to define the first sequenced E. tenella chromosome also defines the E. maxima genome. The significance of such a segmented genome and the apparent potential for variation in genetic recombination will be relevant to haplotype stability and the longevity of future anticoccidial strategies based upon multiple loci targeted by novel chemotherapeutic drugs or recombinant subunit vaccines. Copyright © 2010 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  2. Protection Efficacy of Multivalent Egg Yolk Immunoglobulin against Eimeria Tenella Infection in Chickens

    Directory of Open Access Journals (Sweden)

    JJ Xu

    2013-09-01

    Full Text Available Background: To control avian coccidiosis with drug-independent strategy effec­tively and safely, multivalent hyperimmune egg yolk immunoglobulin (IgY was prepared and its ability to protect against Eimeria tenella infection was evaluated.Methods: Hens were orally immunized with live oocysts of 5 species of Eimeria for six times, antibody titers in serum and yolk were monitored by indirect enzyme-linked immunosorbent assay. The specific IgY was isolated, purified and lyophi­lized. IgY powder was orally administrated as dietary supplement in newly hatched chicks at various dosages. Birds were orally challenged with 10000 sporulated oo­cysts of E. tenella at 10 days of age, weighed and killed at 8 days post challenge, and the protective effect was assessed.Results: The averge yeid of IgY was 9.2 mg/ml yolk, the antibody titer of IgY reached to 1:163840 per mg with the purity up to 98%. Chickens fed IgY resulted in reduced mortality, increased body weight gain (BWG, reduced oocyst shedding, reduced caecal lesion score and increased anti-coccidial index. In terms of BWG and caecal lesion, IgY significantly enhanced the resistance of bird at ≥ 0.05% of IgY in the diet when compared with the challenged control group (P0.05.Conclusion: Supplementing newly hatched chicks with Eimeria-specific IgY represents a promising strategy to prevent avian coccidiosis.

  3. In vitro inhibition of Eimeria tenella sporozoite invasion into host cells by probiotics.

    Science.gov (United States)

    Hessenberger, S; Schatzmayr, G; Teichmann, K

    2016-10-15

    The aim was to study the effects of probiotics isolated from the intestinal tract of livestock animals on Eimeria tenella invasion into Madin-Darby bovine kidney (MDBK) cells in vitro. E. tenella sporozoites were purified and labeled with 5(6)-carboxyfluorescein diacetate N-succinimidyl ester before seeding on cell cultures, and invasion was evaluated by fluorescence microscopy. Two protocols (A and B) were used. In protocol A, Enterococcus faecium # 589 or Lactobacillus salivarius subsp. salivarius # 505 were added together with sporozoites to MDBK cell cultures and invasion was evaluated after incubation for approximately 20h. Viable, dead, or spent culture supernatants of probiotics were tested. In protocol B, viable probiotics were incubated with MDBK cells for one hour before sporozoites were added and invasion was evaluated after two more hours of incubation. Parasite invasion of viable, dead, or spent culture supernatant of E. faecium # 589 was assessed. Using protocol A, it was shown that parasite invasion was inhibited by viable (80%) or dead (75%) E. faecium # 589. While inhibition by viable L. salivarius subsp. salivarius # 505 was not valid at the highest concentration and not significant at the other test concentrations, dead cells inhibited parasite invasion up to 45%. Spent culture supernatants of both probiotics had no influence on parasite invasion. Using protocol B, it was shown that viable Bifidobacterium animalis subsp. animalis # 503, E. faecium # 497, E. faecium # 589, L. reuteri # 514, L. salivarius subsp. salivarius # 505, and Bacillus subtilis # 588 inhibited parasite invasion into MDBK cells up to 80%. Anticoccidial activity was strain-specific for E. faecium strains, and the strongest effect was shown by E. faecium # 589. Anticoccidial effects of some of the tested probiotics have already been shown in vivo, which makes them candidates to prevent coccidiosis. These findings have now been confirmed in vitro. The used parasite invasion

  4. Extracellular vesicles modulate host-microbe responses by altering TLR2 activity and phagocytosis.

    Directory of Open Access Journals (Sweden)

    Jeroen van Bergenhenegouwen

    Full Text Available Oral delivery of Gram positive bacteria, often derived from the genera Lactobacillus or Bifidobacterium, can modulate immune function. Although the exact mechanisms remain unclear, immunomodulatory effects may be elicited through the direct interaction of these bacteria with the intestinal epithelium or resident dendritic cell (DC populations. We analyzed the immune activation properties of Lactobacilli and Bifidobacterium species and made the surprising observation that cellular responses in vitro were differentially influenced by the presence of serum, specifically the extracellular vesicle (EV fraction. In contrast to the tested Lactobacilli species, tested Bifidobacterium species induce TLR2/6 activity which is inhibited by the presence of EVs. Using specific TLR ligands, EVs were found to enhance cellular TLR2/1 and TLR4 responses while TLR2/6 responses were suppressed. No effect could be observed on cellular TLR5 responses. We determined that EVs play a role in bacterial aggregation, suggesting that EVs interact with bacterial surfaces. EVs were found to slightly enhance DC phagocytosis of Bifidobacterium breve whereas phagocytosis of Lactobacillus rhamnosus was virtually absent upon serum EV depletion. DC uptake of a non-microbial substance (dextran was not affected by the different serum fractions suggesting that EVs do not interfere with DC phagocytic capacity but rather modify the DC-microbe interaction. Depending on the microbe, combined effects of EVs on TLR activity and phagocytosis result in a differential proinflammatory DC cytokine release. Overall, these data suggest that EVs play a yet unrecognized role in host-microbe responses, not by interfering in recipient cellular responses but via attachment to, or scavenging of, microbe-associated molecular patterns. EVs can be found in any tissue or bodily fluid, therefore insights into EV-microbe interactions are important in understanding the mechanism of action of potential

  5. TLR4 activates NF-{kappa}B in human ovarian granulosa tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Woods, Dori C., E-mail: dwoods2@partners.org [Vincent Center for Reproductive Biology, Vincent Obstetrics and Gynecology Service, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114 (United States); White, Yvonne A.R. [Vincent Center for Reproductive Biology, Vincent Obstetrics and Gynecology Service, Massachusetts General Hospital/Harvard Medical School, Boston, MA 02114 (United States); Dau, Caroline [University of California, San Francisco, School of Dentistry, San Francisco, CA 94143 (United States); Johnson, A.L. [Center for Reproductive Biology and Health, The Pennsylvania State University, University Park, PA 16802 (United States)

    2011-06-17

    Highlights: {yields} TLR4 is expressed in human ovarian granulosa tumor cells. {yields} Acting through TLR4, LPS and HSP60 induce a NF{kappa}B signaling cascade in human ovarian granulosa tumor cells. {yields} NF{kappa}B activation or inhibition did not alter chemosensitivity to TRAIL or cisplatin. -- Abstract: Previous studies have demonstrated expression of Toll-like receptors (TLRs) in the surface epithelium of normal ovaries (OSE) and in epithelial ovarian tumors. Most notably, OSE-derived cancers express TLR4, which activates the nuclear factor-kappa B (NF-{kappa}B) signaling cascade as a mediator of inflammatory response. Currently, there is considerable interest in elucidating the role of TLR-mediated signaling in cancers. Nevertheless, the expression of TLRs in granulosa cell tumors (GCTs) of the ovary, and the extent to which GCT expression of TLRs may influence cell-signaling pathways and/or modulate the efficacy of chemotherapeutics, has yet to be determined. In the present study, human GCT lines (COV434 and KGN) were utilized to evaluate expression of functional TLR4. TLR4 is expressed in GCT cell lines and ligation of TLR4 with bacterial lipopolysaccharide (LPS) led to I{kappa}B degradation and activation of NF-{kappa}B. NF-{kappa}B activation was confirmed by nuclear localization of NF-{kappa}B p65 following treatment with LPS and the naturally occurring ligand, HSP60. Notably, immunoneutralization of TLR4 blocked nuclear localization, and inhibition of NF-{kappa}B signaling attenuated LPS-induced TNF{alpha} plus increased doubling time in both cell lines. Contradictory to reports using human OSE cell lines, inhibition of NF-{kappa}B signaling failed to sensitize GCT lines to TRAIL or cisplatin. In summary, findings herein are the first to demonstrate a functional TLR-signaling pathway specifically in GCTs, and indicate that in contrast to OSE-derived cancers, inhibition of NF-{kappa}B does not sensitize GCTs to TRAIL or cisplatin.

  6. Gene conversion limits divergence of mammalian TLR1 and TLR6

    Directory of Open Access Journals (Sweden)

    Dunoyer-Geindre Sylvie

    2007-08-01

    Full Text Available Abstract Background Toll-like receptors (TLR recognize pathogen-associated molecular patterns and are important mediators of the innate immune system. TLR1 and TLR6 are paralogs and located in tandem on the same chromosome in mammals. They form heterodimers with TLR2 and bind lipopeptide components of gram-positive and gram-negative bacterial cell walls. To identify conserved stretches in TLR1 and TLR6, that may be important for their function, we compared their protein sequences in nine mammalian species(Homo sapiens, Pan troglodytes, Macaca mulatta, Mus musculus, Rattus norvegicus; Erinaceus europaeus, Bos Taurus, Sus scrofa and Canis familiaris. Results The N-terminal sequences of the orthologous proteins showed greater similarity than corresponding paralog sequences. However, we identified a region of 300 amino acids towards the C-terminus of TLR1 and TLR6, where paralogs had a greater degree of sequence identity than orthologs. Preservation of DNA sequence identity of paralogs in this region was observed in all nine mammalian species investigated, and is due to independent gene conversion events. The regions having undergone gene conversion in each species are almost identical and encode the leucine-rich repeat motifs 16 to 19, the C-terminal cap motif, the transmembrane domain and most of the intracellular Toll/interleukin-1 receptor (TIR domain. Conclusion Our results show that, for a specific conserved region, divergence of TLR1 and TLR6 is limited by gene conversion, most likely because of the need for co-evolution with multiple intracellular and extracellular binding partners. Thus, gene conversion provides a mechanism for limiting the divergence of functional regions of protein paralogs, while allowing other domains to evolve diversified functions.

  7. Antibacterial, antifungal and cytotoxic activities exhibited by endophytic fungi from the Brazilian marine red alga Bostrychia tenella (Ceramiales

    Directory of Open Access Journals (Sweden)

    Rafael de Felício

    Full Text Available Abstract Marine environment is one of the most important sources regarding natural products research. Besides, marine microorganisms have been denominated as a talented natural source for discovery of new leads. Although the association of macroalgae and fungi has been described regarding ecological issues, there is a lack of studies about marine seaweed endophytic fungi. In this context, the goal of this study was to evaluate cytotoxic, antifungal and antibacterial activities of endophytic fungi isolated from the Brazilian marine seaweed Bostrychia tenella (J.V. Lamouroux J. Agardh (Ceramiales, Rhodophyta. Forty-five endophytic microorganism strains were isolated from B. tenella. Crude extracts and organic fractions of ten selected strains were obtained after growth in rice medium. Samples were evaluated for cytotoxicity, antifungal and antibacterial assays. Penicillium strains showed positive results in a diversity of assays, and other five strains were active in at least one test. In addition, cytochalasin D was isolated from Xylaria sp. This alga is composed of a microbiological potential, since its endophytic strains exhibited remarkable biological properties. Moreover, cytochalasin D isolation has confirmed chemical potential of marine endophytic strains. This is the first study in which cultured fungi isolates from the Brazilian macroalga B. tenella were evaluated concerning biological properties. Results corroborated that this species could be a pharmaceutical source from marine environment. Furthermore, Acremonium implicatum is being firstly described as marine endophyte and Xylaria sp., Trichoderma atroviride and Nigrospora oryzae as marine seaweed endophytes. Thus, this work reports the first study relating detailed isolation, cultivation and biological evaluation (cytotoxic, antifungal and antibacterial of endophytes Penicillium decaturense and P. waksmanii from the Brazilian marine red alga B. tenella. We are also reporting the

  8. Embryonated chicken eggs as an alternative model for mixed Clostridium perfringens and Eimeria tenella infection in chickens.

    Science.gov (United States)

    Alnassan, Alaa Aldin; Shehata, Awad Ali; Kotsch, Marianne; Lendner, Matthias; Daugschies, Arwid; Bangoura, Berit

    2013-06-01

    The chorioallantoic membrane (CAM) of chicken embryo eggs is a suitable model for viral and bacterial infections. In the present study, a new approach for testing the pathogenesis and virulence of Clostridium perfringens and Eimeria tenella dual infections as a model using the CAM of embryonated chicken eggs was developed. For this purpose, 24 specific pathogen-free (SPF) embryonated chicken eggs were divided into four groups (n = 6) and designated group E, group CP, group CPE, and NC. Sporozoites of E. tenella (20,000 sporozoites) were inoculated into 10-day-old embryonated SPF chicken eggs (groups E and CPE) via allantoic sac route. At 15-day-old, eggs of groups CP and CPE were infected with 10 (4)  cfu C. perfringens via the same route. Assessment of pathogenicity was assessed using gross and histopathological lesions. Embryo mortality reached 17 % after mono-infection with C. perfringens and/or E. tenella and 50 % in the mixed-infected group. Lesions in the CAMs were most numerous and most severe in co-infected eggs (group CPE), reaching the maximum score of 3 in 50 % of the inoculated eggs (P < 0.01). In Eimeria spp.-infected eggs (group E), lesions of score were between 1 and 2. Mono-infection with C. perfringens did not lead to a significant occurrence of lesions. Histopathological investigations of the CAM revealed clusters of Gram-positive bacteria, infiltration with leukocytes, lymphocytes, and developmental stages of E. tenella in the co-infected group. These data suggest that embryonated eggs could be an in ovo model for studying the pathogenesis of mixed infection with Eimeria and C. perfringens.

  9. Evaluation of immunomodulatory and anti-inflammatory effects and phytochemical screening of Alternanthera tenella Colla (Amaranthaceae aqueous extracts

    Directory of Open Access Journals (Sweden)

    Carla de Agostino Biella

    2008-09-01

    Full Text Available Alternanthera tenella Colla extracts are used in Brazilian traditional folk medicine to treat a variety of infectious diseases as well as inflammation and fever. In this work, the immunomodulatory, anti-inflammatory and potential toxic effects of cold (CAE and hot (HAE aqueous extracts of A. tenella were investigated in vivo. In addition, we analyzed the phytochemical properties of both extracts. BALB/c mice were immunized in vivo with sheep red blood cells and concomitantly inoculated intraperitoneally (i.p. with each extract (50, 100 or 200 mg/kg. Specific antibody-producing cells were enumerated using plaque-forming cell assays (PFC and anti-SRBC IgG and IgM serum levels were measured via enzyme-linked immunosorbent assay. Body and lymphoid organ weights were determined after treatments in order to evaluate toxic effects. Carrageenan-induced paw edema was employed to investigate anti-inflammatory activity in mice inoculated i.p. with CAE or HAE (200 or 400 mg/kg. Phytochemical screening was performed using spectrometric and chromatographic approaches and revealed that CAE possessed higher tannin and flavonoid levels than HAE. PFC numbers were increased after treatment with CAE (100 mg/kg four days after immunization, as were the serum antibody titers after four and seven days, suggesting immunostimulatory activity through modulation of B lymphocyte functions. Body and organ weights did not show major changes, suggesting that extracts administered to mice did not induce significant toxicity. Both extracts had significant anti-inflammatory activity in the paw edema assay. These results suggested that aqueous extracts from A. tenella contained several chemical compounds that possess positive and/or negative modulator effects on the immune system, which appeared to correlate with tannin and flavonoid levels in those extracts. In summary, these studies provide important insight into the biological activities of A. tenella.

  10. Repurposed transcriptomic data facilitate discovery of innate immunity toll-like receptor (TLR) Genes across Lophotrochozoa.

    Science.gov (United States)

    Halanych, Kenneth M; Kocot, Kevin M

    2014-10-01

    The growing volume of genomic data from across life represents opportunities for deriving valuable biological information from data that were initially collected for another purpose. Here, we use transcriptomes collected for phylogenomic studies to search for toll-like receptor (TLR) genes in poorly sampled lophotrochozoan clades (Annelida, Mollusca, Brachiopoda, Phoronida, and Entoprocta) and one ecdysozoan clade (Priapulida). TLR genes are involved in innate immunity across animals by recognizing potential microbial infection. They have an extracellular leucine-rich repeat (LRR) domain connected to a transmembrane domain and an intracellular toll/interleukin-1 receptor (TIR) domain. Consequently, these genes are important in initiating a signaling pathway to trigger defense. We found at least one TLR ortholog in all but two taxa examined, suggesting that a broad array of lophotrochozoans may have innate immune systems similar to those observed in vertebrates and arthropods. Comparison to the SMART database confirmed the presence of both the LRR and the TIR protein motifs characteristic of TLR genes. Because we looked at only one transcriptome per species, discovery of TLR genes was limited for most taxa. However, several TRL-like genes that vary in the number and placement of LRR domains were found in phoronids. Additionally, several contigs contained LRR domains but lacked TIR domains, suggesting they were not TLRs. Many of these LRR-containing contigs had other domains (e.g., immunoglobin) and are likely involved in innate immunity. © 2014 Marine Biological Laboratory.

  11. The response of red ginger (Zinggiber officinalle var rubra) with various processing in broilers were infected by Eimeria tenella

    Science.gov (United States)

    Nasution, E. Z. J.; Tafsin, M.; Hanafi, N. D.

    2018-02-01

    Red ginger contains high antioxidants and have anti -inflamatory properties. Ginger also has the ability to treat kimiatif, antiemetic, antinausea, and antiparasitik. The aim of this experiment was identified the response of red ginger in broilers were infected by Eimeria tenella. This research used Completely Randomized Design (CRD) with 5 treatments and 4 replications. Eimeria tenella were infected by 10.000 oocysts / head and red ginger solution were aplicated with 1% concentration. The treatments consist of KP (positive control), KO (coccidiostat), K1 (red ginger powder), K2 (extracted red ginger by ethanol) and K3 (extracted red ginger by water) . The results showed that the treatment of red ginger was significant effect (PEimeria tenella. The comparison between extracted red ginger by ethanol is better than by water or in powder form to decreased. The utilization of red ginger showed the percentage of heterophile and eosinophile close to normal when compared with positive control. Assesment of caecum lesion score was not significant (P>0.05) different effect between all the treatments. It is concluded that the treatment by red ginger better than coccidiostat and positive control.

  12. Fruit and seed biometry of cambuí (Myrciaria tenella O. Berg = Biometria de fruto e semente de cambuí (Myrciaria tenella O. Berg

    Directory of Open Access Journals (Sweden)

    Ana Veruska Cruz da Silva

    2012-12-01

    Full Text Available The cambuí tree (Myrciaria tenella O. Berg is native to Brazil and its fruits are harvested by extraction for fresh consumption in the state of Sergipe (Brazil. Because of the regional importance of the species, this work aims to characterize the cambuí fruits and seeds. The fruits were harvested mature from native trees in the Reserva do Caju Experimental Field, on Itaporanga d’Ajuda (Sergipe, Brazil, belonging to Embrapa Tabuleiros Costeiros. Two hundred fruits and seeds were biometrically analyzed. In addition, we evaluated the fruit, pulp, and seed color based on RHS Color Chart. Two different skin colors were found: 1. yellow [orange - red (group 32A] with yellow pulp [yellow - orange (group 17A]; and 2. purple [violet -blue (group 93A] with red pulp [red - purple (group 60A]. The seeds have only one color, green [yellow-green (group 152A] with dark stripes [Brown (group 200C]. The fruits mean diameter was 9.23 mm.fruit-1, and average width 8.50 mm.fruit-1. The seeds mean diameter was 5.34 mm.seed-1, mean width 6.52 mm.seed-1 and thickness 5.08 mm.seed-1. The cambuí is a little red fruit. The biometry had a high variability as expected, because it is a native species without any type of management.=Resumo - O cambuí (Myrciaria tenella O. Berg é nativo do Brasil e os frutos são colhidos por extrativismo para consumo in natura no estado de Sergipe (Brasil. Por causa da importância regional da espécie, objetivou-se com este trabalho caracterizar os frutos e sementes de cambuí. Os frutos foram colhidos maduros provenientes de plantas nativas do Campo Experimental Reserva do Caju, no município de Itaporanga d’Ajuda (Sergipe, Brasil pertencente a Embrapa Tabuleiros Costeiros. Foram analisados 200 frutos e sementes biometricamente. Além disso, caracterizou-se a cor da fruta, da polpa, e da semente com base na cartela de cores RHS. Foram identificados duas cores diferentes para a fruta: 1. de cor amarela [laranja - vermelho (grupo32A

  13. Histones from Dying Renal Cells Aggravate Kidney Injury via TLR2 and TLR4

    Science.gov (United States)

    Allam, Ramanjaneyulu; Scherbaum, Christina Rebecca; Darisipudi, Murthy Narayana; Mulay, Shrikant R.; Hägele, Holger; Lichtnekert, Julia; Hagemann, Jan Henrik; Rupanagudi, Khader Valli; Ryu, Mi; Schwarzenberger, Claudia; Hohenstein, Bernd; Hugo, Christian; Uhl, Bernd; Reichel, Christoph A.; Krombach, Fritz; Monestier, Marc; Liapis, Helen; Moreth, Kristin; Schaefer, Liliana

    2012-01-01

    In AKI, dying renal cells release intracellular molecules that stimulate immune cells to secrete proinflammatory cytokines, which trigger leukocyte recruitment and renal inflammation. Whether the release of histones, specifically, from dying cells contributes to the inflammation of AKI is unknown. In this study, we found that dying tubular epithelial cells released histones into the extracellular space, which directly interacted with Toll-like receptor (TLR)-2 (TLR2) and TLR4 to induce MyD88, NF-κB, and mitogen activated protein kinase signaling. Extracellular histones also had directly toxic effects on renal endothelial cells and tubular epithelial cells in vitro. In addition, direct injection of histones into the renal arteries of mice demonstrated that histones induce leukocyte recruitment, microvascular vascular leakage, renal inflammation, and structural features of AKI in a TLR2/TLR4-dependent manner. Antihistone IgG, which neutralizes the immunostimulatory effects of histones, suppressed intrarenal inflammation, neutrophil infiltration, and tubular cell necrosis and improved excretory renal function. In summary, the release of histones from dying cells aggravates AKI via both its direct toxicity to renal cells and its proinflammatory effects. Because the induction of proinflammatory cytokines in dendritic cells requires TLR2 and TLR4, these results support the concept that renal damage triggers an innate immune response, which contributes to the pathogenesis of AKI. PMID:22677551

  14. TLR2/TLR4 activation induces Tregs and suppresses intestinal inflammation caused by Fusobacterium nucleatum in vivo.

    Directory of Open Access Journals (Sweden)

    Yin-Ping Jia

    Full Text Available Toll-like receptors (TLRs 2 and 4 play critical roles in intestinal inflammation caused by Fusobacterium nucleatum (F. nucleatum infection, but the role of TLR2/TLR4 in regulation of proinflammatory cytokines remains unknown. In this study, through microarray analysis and qRT-PCR, we showed that TLR2/TLR4 are involved in the F. nucleatum-induced inflammatory signaling pathway in Caco-2 cells, C57BL/6 mice and human clinical specimens. In TLR2-/- and TLR4-/- mice, F. nucleatum infection resulted in increased colonization of the bacteria and production of the proinflammatory cytokines IL-8, IL-1β and TNF-α. In addition, the ratio of Foxp3+ CD4+ T cells in the total CD4+ T cells in TLR2-/- and TLR4-/- mice was less than that in wild-type mice, and the ratio in hybrid mice was more than that in knockout mice, which suggested that TLR2/TLR4 mediated the number of Tregs. Furthermore, it was observed that inflammatory cytokine levels were reduced in TLR2-/- mice after Treg transfer. Thus, these data indicate that TLR2/TLR4 regulate F. nucleatum-induced inflammatory cytokines through Tregs in vivo.

  15. Modulation of endotoxicity of Shigella generalized modules for membrane antigens (GMMA) by genetic lipid A modifications: relative activation of TLR4 and TLR2 pathways in different mutants.

    Science.gov (United States)

    Rossi, Omar; Pesce, Isabella; Giannelli, Carlo; Aprea, Susanna; Caboni, Mariaelena; Citiulo, Francesco; Valentini, Sara; Ferlenghi, Ilaria; MacLennan, Calman Alexander; D'Oro, Ugo; Saul, Allan; Gerke, Christiane

    2014-09-05

    Outer membrane particles from Gram-negative bacteria are attractive vaccine candidates as they present surface antigens in their natural context. We previously developed a high yield production process for genetically derived particles, called generalized modules for membrane antigens (GMMA), from Shigella. As GMMA are derived from the outer membrane, they contain immunostimulatory components, especially lipopolysaccharide (LPS). We examined ways of reducing their reactogenicity by modifying lipid A, the endotoxic part of LPS, through deletion of late acyltransferase genes, msbB or htrB, in GMMA-producing Shigella sonnei and Shigella flexneri strains. GMMA with resulting penta-acylated lipid A from the msbB mutants showed a 600-fold reduced ability, and GMMA from the S. sonnei ΔhtrB mutant showed a 60,000-fold reduced ability compared with GMMA with wild-type lipid A to stimulate human Toll-like receptor 4 (TLR4) in a reporter cell line. In human peripheral blood mononuclear cells, GMMA with penta-acylated lipid A showed a marked reduction in induction of inflammatory cytokines (S. sonnei ΔhtrB, 800-fold; ΔmsbB mutants, 300-fold). We found that the residual activity of these GMMA is largely due to non-lipid A-related TLR2 activation. In contrast, in the S. flexneri ΔhtrB mutant, a compensatory lipid A palmitoleoylation resulted in GMMA with hexa-acylated lipid A with ∼10-fold higher activity to stimulate peripheral blood mononuclear cells than GMMA with penta-acylated lipid A, mostly due to retained TLR4 activity. Thus, for use as vaccines, GMMA will likely require lipid A penta-acylation. The results identify the relative contributions of TLR4 and TLR2 activation by GMMA, which need to be taken into consideration for GMMA vaccine development. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Postnatal TLR2 activation impairs learning and memory in adulthood.

    Science.gov (United States)

    Madar, Ravit; Rotter, Aviva; Waldman Ben-Asher, Hiba; Mughal, Mohamed R; Arumugam, Thiruma V; Wood, W H; Becker, K G; Mattson, Mark P; Okun, Eitan

    2015-08-01

    Neuroinflammation in the central nervous system is detrimental for learning and memory, as evident form epidemiological studies linking developmental defects and maternal exposure to harmful pathogens. Postnatal infections can also induce neuroinflammatory responses with long-term consequences. These inflammatory responses can lead to motor deficits and/or behavioral disabilities. Toll like receptors (TLRs) are a family of innate immune receptors best known as sensors of microbial-associated molecular patterns, and are the first responders to infection. TLR2 forms heterodimers with either TLR1 or TLR6, is activated in response to gram-positive bacterial infections, and is expressed in the brain during embryonic development. We hypothesized that early postnatal TLR2-mediated neuroinflammation would adversely affect cognitive behavior in the adult. Our data indicate that postnatal TLR2 activation affects learning and memory in adult mice in a heterodimer-dependent manner. TLR2/6 activation improved motor function and fear learning, while TLR2/1 activation impaired spatial learning and enhanced fear learning. Moreover, developmental TLR2 deficiency significantly impairs spatial learning and enhances fear learning, stressing the involvement of the TLR2 pathway in learning and memory. Analysis of the transcriptional effects of TLR2 activation reveals both common and unique transcriptional programs following heterodimer-specific TLR2 activation. These results imply that adult cognitive behavior could be influenced in part, by activation or alterations in the TLR2 pathway at birth. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Self-incompatibility of Prunus tenella and evidence that reproductively isolated species of Prunus have different SFB alleles coupled with an identical S-RNase allele.

    Science.gov (United States)

    Surbanovski, Nada; Tobutt, Kenneth R; Konstantinović, Miroslav; Maksimović, Vesna; Sargent, Daniel J; Stevanović, Vladimir; Bosković, Radovan I

    2007-05-01

    Many species of Prunus display an S-RNase-based gametophytic self-incompatibility (SI), controlled by a single highly polymorphic multigene complex termed the S-locus. This comprises tightly linked stylar- and pollen-expressed genes that determine the specificity of the SI response. We investigated SI of Prunus tenella, a wild species found in small, isolated populations on the Balkan peninsula, initially by pollination experiments and identifying stylar-expressed RNase alleles. Nine P. tenella S-RNase alleles (S(1)-S(9)) were cloned; their sequence analysis showed a very high ratio of non-synonymous to synonymous nucleotide substitutions (K(a)/K(s)) and revealed that S-RNase alleles of P. tenella, unlike those of Prunus dulcis, show positive selection in all regions except the conserved regions and that between C2 and RHV. Remarkably, S(8)-RNase, was found to be identical to S(1)-RNase from Prunus avium, a species that does not interbreed with P. tenella and, except for just one amino acid, to S(11) of P. dulcis. However, the corresponding introns and S-RNase-SFB intergenic regions showed considerable differences. Moreover, protein sequences of the pollen-expressed SFB alleles were not identical, harbouring 12 amino-acid replacements between those of P. tenella SFB(8) and P. avium SFB(1). Implications of this finding for hypotheses about the evolution of new S-specificities are discussed.

  18. Bovine TLR2 and TLR4 mediate Cryptosporidium parvum recognition in bovine intestinal epithelial cells.

    Science.gov (United States)

    Yang, Zhengtao; Fu, Yunhe; Gong, Pengtao; Zheng, Jingtong; Liu, Li; Yu, Yuqiang; Li, Jianhua; Li, He; Yang, Ju; Zhang, Xichen

    2015-08-01

    Cryptosporidium parvum (C. parvum) is an intestinal parasite that causes diarrhea in neonatal calves. It results in significant morbidity of neonatal calves and economic losses for producers worldwide. Innate resistance against C. parvum is thought to depend on engagement of pattern recognition receptors. However, the role of innate responses to C. parvum has not been elucidated in bovine. The aim of this study was to evaluate the role of TLRs in host-cell responses during C. parvum infection of cultured bovine intestinal epithelial cells. The expressions of TLRs in bovine intestinal epithelial cells were detected by qRT-PCR. To determine which, if any, TLRs may play a role in the response of bovine intestinal epithelial cells to C. parvum, the cells were stimulated with C. parvum and the expression of TLRs were tested by qRT-PCR. The expression of NF-κB was detected by western blotting. Further analyses were carried out in bovine TLRs transfected HEK293 cells and by TLRs-DN transfected bovine intestinal epithelial cells. The results showed that bovine intestinal epithelial cells expressed all known TLRs. The expression of TLR2 and TLR4 were up-regulated when bovine intestinal epithelial cells were treated with C. parvum. Meanwhile, C. parvum induced IL-8 production in TLR2 or TLR4/MD-2 transfected HEK293 cells. Moreover, C. parvum induced NF-κB activation and cytokine expression in bovine intestinal epithelial cells. The induction of NF-κB activation and cytokine expression by C. parvum were reduced in TLR2-DN and TLR4-DN transfected cells. The results showed that bovine intestinal epithelial cells expressed all known TLRs, and bovine intestinal epithelial cells recognized and responded to C. parvum via TLR2 and TLR4. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Reprogramming of murine macrophages through TLR2 confers viral resistance via TRAF3-mediated, enhanced interferon production.

    Directory of Open Access Journals (Sweden)

    Darren J Perkins

    Full Text Available The cell surface/endosomal Toll-like Receptors (TLRs are instrumental in initiating immune responses to both bacteria and viruses. With the exception of TLR2, all TLRs and cytosolic RIG-I-like receptors (RLRs with known virus-derived ligands induce type I interferons (IFNs in macrophages or dendritic cells. Herein, we report that prior ligation of TLR2, an event previously shown to induce "homo" or "hetero" tolerance, strongly "primes" macrophages for increased Type I IFN production in response to subsequent TLR/RLR signaling. This occurs by increasing activation of the transcription factor, IFN Regulatory Factor-3 (IRF-3 that, in turn, leads to enhanced induction of IFN-β, while expression of other pro-inflammatory genes are suppressed (tolerized. In vitro or in vivo "priming" of murine macrophages with TLR2 ligands increase virus-mediated IFN induction and resistance to infection. This priming effect of TLR2 is mediated by the selective upregulation of the K63 ubiquitin ligase, TRAF3. Thus, we provide a mechanistic explanation for the observed antiviral actions of MyD88-dependent TLR2 and further define the role of TRAF3 in viral innate immunity.

  20. ABEJAS VISITANTES DE Aspilia tenella (KUNTH S. F. BLAKE (ASTERACEAE: COMPORTAMIENTO DE FORRAJEO Y CARGAS POLÍNICAS BEES VISITING Aspilia tenella (KUNTH S .F. BLAKE (ASTERACEAE: FORAGING BEHAVIOR AND POLLEN LOADS

    Directory of Open Access Journals (Sweden)

    Clara Isabel Aguilar Sierra

    2008-12-01

    Full Text Available En cuatro localidades de la zona de influencia del embalse Porce II (Antioquia, Colombia, se observó el comportamiento de 23 taxones de abejas durante sus visitas a Aspilia tenella (Kunth S. F. Blake; se registró el número de individuos y el tiempo total de visita y se midieron la temperatura y la humedad relativa. Los análisis de varianza indican que hubo una relación estadísticamente significativa en cuanto a los atributos considerados para las especies de abejas y una covariación significativa con las variables ambientales. Las pruebas de rangos múltiples muestran que Trigona nigerrima es la especie con los mayores valores promedio para el número de individuos y el tiempo de visita. En el estudio de las cargas polínicas se encontraron 30 tipos polínicos, dentro de los cuales A. tenella presentó el mayor porcentaje; Piper aduncum, Miconia minuti flora, Psidium guajava, Rapanea sp., Mimosa pudica y Psychotria sp., en su orden, son otras fuentes de polen importantes para varias de las especies de abejas. El análisis de agrupamiento para las abejas capturadas permitió diferenciar dos grupos: el primero incluye a 18 especies cuyas cargas polínicas que poseían una abundancia relativa de granos de polen de A. tenella por encima de 77%; el segundo grupo estaba conformado por cinco especies de abejas que recolectaron porcentajes mayores de otros tipos polínicos: Exomalopsis sp. 1 (90,4% de M. minuti flora; Lasioglossum sp. 1 y Coelioxys aff. mexicana (77,4% y 64,1% de P. aduncum, respectivamente; Exomalopsis sp. 2 (67,1% de P. guajava y Auglochloropsis vesta (55,5% de Rapanea sp.. Trigona fulviventris y Apis mellifera presentaron los valores más altos de riqueza de tipos polínicos en las cargas de polen; ello evidencia sus nichos tróficos amplios y su comportamiento generalista de visita.We observed the behavior of 23 species of wild bees visiting Aspilia tenella (Kunth S .F. Blake in four different localities of the Porce II dam

  1. Effect of irradiation (gamma rays) on the biology of Eimeria tenella oocysts

    Energy Technology Data Exchange (ETDEWEB)

    Bajwa, R.S.; Gill, B.S.

    1977-01-01

    Effect of gamma rays on the biology of the progeny of the irradiated Eimeria tenella oocysts was investigated. The parent inoculum of sporulated oocysts was exposed to 5 to 60 kR (gamma rays). These oocysts were fed to chicks. The oocysts voided by the chicks were collected and sporulated. The sporulation rate, pathogenicity, immunogenicity and reproduction potential of these oocysts--the progeny of the irradiated oocysts--were compared with those of the unirradiated oocysts. It was observed that increase of irradiation dose caused progressive decrease in the pathogenicity of the oocyst suspension. The oocysts exposed to 30 and 40 kR produced only mild infections whereas those exposed to 50 kR and above were noninfective. No difference in pathogenicity, immunogenicity and reproduction potential of unirradiated oocysts and the oocysts progeny of the irradiated oocysts was seen. It was concluded, therefore, that the effect of irradiation was limited to the inoculum exposed to it, and was not transmissible to the progeny of the irradiated oocysts.

  2. Identification and characterization of Eimeria tenella apical membrane antigen-1 (AMA1.

    Directory of Open Access Journals (Sweden)

    Lianlian Jiang

    Full Text Available Apical membrane antigen-1 (AMA1 is a micronemal protein of apicomplexan parasites that appears to be essential during the invasion of host cells. In this study, a full-length cDNA of AMA1 was identified from Eimeria tenella (Et using expressed sequence tag and the rapid amplification of cDNA ends technique. EtAMA1 had an open reading frame of 1608 bp encoding a protein of 535 amino acids. Quantitative real-time PCR analysis revealed that EtAMA1 was expressed at higher levels in sporozoites than in the other developmental stages (unsporulated oocysts, sporulated oocysts and second-generation merozoites. The ectodomain sequence was expressed as recombinant EtAMA1 (rEtAMA1 and rabbit polyclonal antibodies raised against the rEtAMA1 recognized a 58-kDa native parasite protein by Western Blotting and had a potent inhibitory effect on parasite invasion, decreasing it by approximately 70%. Immunofluorescence analysis and immunohistochemistry analysis showed EtAMA1 might play an important role in sporozoite invasion and development.

  3. Dietary Curcuma longa enhances resistance against Eimeria maxima and Eimeria tenella infections in chickens.

    Science.gov (United States)

    Kim, Duk Kyung; Lillehoj, Hyun S; Lee, Sung Hyen; Jang, Seung I; Lillehoj, Erik P; Bravo, David

    2013-10-01

    The effects of dietary supplementation with an organic extract of Curcuma longa on systemic and local immune responses to experimental Eimeria maxima and Eimeria tenella infections were evaluated in commercial broiler chickens. Dietary supplementation with C. longa enhanced coccidiosis resistance as demonstrated by increased BW gains, reduced fecal oocyst shedding, and decreased gut lesions compared with infected birds fed a nonsupplemented control diet. The chickens fed C. longa-supplemented diet showed enhanced systemic humoral immunity, as assessed by greater levels of serum antibodies to an Eimeria microneme protein, MIC2, and enhanced cellular immunity, as measured by concanavalin A-induced spleen cell proliferation, compared with controls. At the intestinal level, genome-wide gene expression profiling by microarray hybridization identified 601 differentially expressed transcripts (287 upregulated, 314 downregulated) in gut lymphocytes of C. longa-fed chickens compared with nonsupplemented controls. Based on the known functions of the corresponding mammalian genes, the C. longa-induced intestinal transcriptome was mostly associated with genes mediating anti-inflammatory effects. Taken together, these results suggest that dietary C. longa could be used to attenuate Eimeria-induced, inflammation-mediated gut damage in commercial poultry production.

  4. Toll-like receptor 4 mediates microglial activation and production of inflammatory mediators in neonatal rat brain following hypoxia: role of TLR4 in hypoxic microglia

    Science.gov (United States)

    2013-01-01

    Background Hypoxia induces microglial activation which causes damage to the developing brain. Microglia derived inflammatory mediators may contribute to this process. Toll-like receptor 4 (TLR4) has been reported to induce microglial activation and cytokines production in brain injuries; however, its role in hypoxic injury remains uncertain. We investigate here TLR4 expression and its roles in neuroinflammation in neonatal rats following hypoxic injury. Methods One day old Wistar rats were subjected to hypoxia for 2 h. Primary cultured microglia and BV-2 cells were subjected to hypoxia for different durations. TLR4 expression in microglia was determined by RT-PCR, western blot and immunofluorescence staining. Small interfering RNA (siRNA) transfection and antibody neutralization were employed to downregulate TLR4 in BV-2 and primary culture. mRNA and protein expression of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and inducible nitric oxide synthase (iNOS) was assessed. Reactive oxygen species (ROS), nitric oxide (NO) and NF-κB levels were determined by flow cytometry, colorimetric and ELISA assays respectively. Hypoxia-inducible factor-1 alpha (HIF-1α) mRNA and protein expression was quantified and where necessary, the protein expression was depleted by antibody neutralization. In vivo inhibition of TLR4 with CLI-095 injection was carried out followed by investigation of inflammatory mediators expression via double immunofluorescence staining. Results TLR4 immunofluorescence and protein expression in the corpus callosum and cerebellum in neonatal microglia were markedly enhanced post-hypoxia. In vitro, TLR4 protein expression was significantly increased in both primary microglia and BV-2 cells post-hypoxia. TLR4 neutralization in primary cultured microglia attenuated the hypoxia-induced expression of TNF-α, IL-1β and iNOS. siRNA knockdown of TLR4 reduced hypoxia-induced upregulation of TNF-α, IL-1β, iNOS, ROS and NO in BV-2 cells. TLR4

  5. DMPD: The Troll in Toll: Mal and Tram as bridges for TLR2 and TLR4 signaling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17449723 The Troll in Toll: Mal and Tram as bridges for TLR2 and TLR4 signaling. Sh...Show The Troll in Toll: Mal and Tram as bridges for TLR2 and TLR4 signaling. PubmedID 17449723 Title The Tro...ll in Toll: Mal and Tram as bridges for TLR2 and TLR4 signaling. Authors Sheedy F

  6. Stimulants of Toll-like receptor (TLR)-2 and TLR-4 are abundant in certain minimally-processed vegetables.

    Science.gov (United States)

    Erridge, Clett

    2011-06-01

    Stimulants of the innate immune receptors Toll-like receptor (TLR)-2 and TLR4 have been shown to promote insulin resistance and atherosclerosis in animal models of these diseases. As minimally processed vegetables (MPV) can contain a relatively large bacterial load compared to other foodstuffs, we aimed to quantify the abundance of stimulants of TLR2 and TLR4 in MPV using a transfection-based bioassay calibrated with Escherichia coli LPS and the synthetic lipopeptide Pam(3)CSK(4). Of 5 classes of MPV and 3 classes of related vegetable products considered to be likely to contain a high microbial load, diced onion and bean sprouts contained the highest levels of stimulants of TLR2 (up to 18.5 μg Pam(3)CSK(4)-equivalents per g) and TLR4 (up to 11.4 μg LPS-equivalents per g). By contrast, the majority of fresh whole vegetables examined reproducibly contained minimal or undetectable levels of TLR2- or TLR4-stimulants. The accumulation of TLR-stimulants in MPVs correlated well with growth of enterobacterial spoilage organisms. In conclusion, the modern trend towards eating minimally processed vegetables rather than whole foods is likely to be associated with increased oral exposure to stimulants of TLR2 and TLR4. Copyright © 2011 Elsevier Ltd. All rights reserved.

  7. Structure-based discovery of an immunomodulatory inhibitor of TLR1-TLR2 heterodimerization from a natural product-like database.

    Science.gov (United States)

    Zhong, Zhangfeng; Liu, Li-Juan; Dong, Zhi-Qiang; Lu, Lihua; Wang, Modi; Leung, Chung-Hang; Ma, Dik-Lung; Wang, Yitao

    2015-06-30

    We report herein the identification of an immunomodulatory natural product-like compound as a direct inhibitor of TLR1-TLR2 heterodimerization. Compound suppressed TNF-α and IL-6 secretion in Pam3CSK4-induced macrophages. Moreover, compound inhibited the phagocytic activity of macrophages, presumably through modulation of TLR1-TLR2 signaling and inactivation of NF-κB. Molecular docking revealed that compound bound to the interface region of TLR1-TLR2 by forming two hydrogen bonds with residues lining the binding site. To our knowledge, compound has been only the second inhibitor overall of TLR1-TLR2 heterodimerization reported to date.

  8. Poly-thymidine oligonucleotides mediate activation of murine glial cells primarily through TLR7, not TLR8.

    Directory of Open Access Journals (Sweden)

    Min Du

    Full Text Available The functional role of murine TLR8 in the inflammatory response of the central nervous system (CNS remains unclear. Murine TLR8 does not appear to respond to human TLR7/8 agonists, due to a five amino acid deletion in the ectodomain. However, recent studies have suggested that murine TLR8 may be stimulated by alternate ligands, which include vaccinia virus DNA, phosphothioate oligodeoxynucleotides (ODNs or the combination of phosphothioate poly-thymidine oligonucleotides (pT-ODNs with TLR7/8 agonists. In the current study, we analyzed the ability of pT-ODNs to induce activation of murine glial cells in the presence or absence of TLR7/8 agonists. We found that TLR7/8 agonists induced the expression of glial cell activation markers and induced the production of multiple proinflammatory cytokines and chemokines in mixed glial cultures. In contrast, pT-ODNs alone induced only low level expression of two cytokines, CCL2 and CXCL10. The combination of pT-ODNs along with TLR7/8 agonists induced a synergistic response with substantially higher levels of proinflammatory cytokines and chemokines compared to CL075. This enhancement was not due to cellular uptake of the agonist, indicating that the pT-ODN enhancement of cytokine responses was due to effects on an intracellular process. Interestingly, this response was also not due to synergistic stimulation of both TLR7 and TLR8, as the loss of TLR7 abolished the activation of glial cells and cytokine production. Thus, pT-ODNs act in synergy with TLR7/8 agonists to induce strong TLR7-dependent cytokine production in glial cells, suggesting that the combination of pT-ODNs with TLR7 agonists may be a useful mechanism to induce pronounced glial activation in the CNS.

  9. Comparative Microarray Analysis of Intestinal Lymphocytes following Eimeria acervulina, E. maxima, or E. tenella Infection in the Chicken

    Science.gov (United States)

    Kim, Duk Kyung; Lillehoj, Hyun; Min, Wongi; Kim, Chul Hong; Park, Myeong Seon; Hong, Yeong Ho; Lillehoj, Erik P.

    2011-01-01

    Relative expression levels of immune- and non-immune-related mRNAs in chicken intestinal intraepithelial lymphocytes experimentally infected with Eimeria acervulina, E. maxima, or E. tenella were measured using a 10K cDNA microarray. Based on a cutoff of >2.0-fold differential expression compared with uninfected controls, relatively equal numbers of transcripts were altered by the three Eimeria infections at 1, 2, and 3 days post-primary infection. By contrast, E. tenella elicited the greatest number of altered transcripts at 4, 5, and 6 days post-primary infection, and at all time points following secondary infection. When analyzed on the basis of up- or down-regulated transcript levels over the entire 6 day infection periods, approximately equal numbers of up-regulated transcripts were detected following E. tenella primary (1,469) and secondary (1,459) infections, with a greater number of down-regulated mRNAs following secondary (1,063) vs. primary (890) infection. On the contrary, relatively few mRNA were modulated following primary infection with E. acervulina (35 up, 160 down) or E. maxima (65 up, 148 down) compared with secondary infection (E. acervulina, 1,142 up, 1,289 down; E. maxima, 368 up, 1,349 down). With all three coccidia, biological pathway analysis identified the altered transcripts as belonging to the categories of “Disease and Disorder” and “Physiological System Development and Function”. Sixteen intracellular signaling pathways were identified from the differentially expressed transcripts following Eimeria infection, with the greatest significance observed following E. acervulina infection. Taken together, this new information will expand our understanding of host-pathogen interactions in avian coccidiosis and contribute to the development of novel disease control strategies. PMID:22140460

  10. Identification and characterisation of TLR18-21 genes in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Lee, P T; Zou, J; Holland, J W; Martin, S A M; Collet, B; Kanellos, T; Secombes, C J

    2014-12-01

    Teleost fish possess many types of toll-like receptor (TLR) some of which exist in other vertebrate groups and some that do not (ie so-called "fish-specific" TLRs). In this study, we identified in Atlantic salmon (Salmo salar) whole-genome shotgun (WGS) contigs seven TLRs that are not found in mammals, including six types of fish-specific TLRs (one TLR18, one TLR19, and four TLR20 members (two of which are putative soluble forms (s)) and one TLR21. Phylogenetic analysis revealed that teleost TLR19-21 are closely related with murine TLR11-TLR13, whilst teleost TLR18 groups with mammalian TLR1, 2, 6 and 10. A typical TLR protein domain structure was found in all these TLRs with the exception of TLR20b(s) and TLR20c(s). TLR-GFP expression plasmids transfected into SHK-1 cells showed that salmon TLR19, TLR20a and TLR20d were preferentially localised to the intracellular compartment. Real time PCR analysis suggested that salmon TLR19-TLR21 are mainly expressed in immune related organs, such as spleen, head kidney and gills, while TLR18 transcripts are more abundant in muscle. In vitro stimulation of primary head kidney cells with type I IFN, IFNγ and IL-1β had no impact on TLR expression. Infectious salmon anaemia virus (ISAV) infection, in vivo, down-regulated TLR20a, TLR20b(s), TLR20d and TLR21 in infected salmon kidney tissue. In contrast, up-regulation of TLR19 and TLR20a expression was found in posterior kidney in rainbow trout with clinical proliferative kidney disease (PKD). Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Ameliorative effect of mycofix plus 3.0 in reducing intensity of Eimeria tenella infection during aflatoxicosis in broiler chicks

    Directory of Open Access Journals (Sweden)

    A. M. Shareef

    2008-01-01

    Full Text Available One hundred and sixty male broiler chicks were fed at one day of age aflatoxin (AF at a rate of 3.5 mg/kg alone, or with groups injected with Eimeria tenella sporulated oocysts (40000 at 14 days of age. Adsorbent (Mycofix® plus 3.0 was incorporated at a rate of 0.25% in the above mentioned groups from one day of age till the end of the experiment. The study was conducted to reveal the effect of a aforementioned different diets and treatments on live body weight, feed consumption, feed conversion ratio, blood parameters (total red blood cells, hemoglobin, packed cell volume, biochemical profile of serum (alkaline phosphatase and β-carotin, liver weights, bursal and thymus indexes, caecal lesion scores and mortalities. The results indicated that AF was responsible for a significant (P<0.05 reduction. in body weigh gain (BWG, feed consumption, and an increase in feed conversion ratio. Afllatoxin was also responsible for reduction in blood parameters, β-Carotin, bursal and thymus indexes. While relative liver weight and alkaline phosphatase level were significantly (P<0.05 increased. Groups that fed AF at a rate of 3.5 mg/kg feed and exposed to sporulated oocysts of Eimeria tenella show a high significant (P<0.05 reduction in BWG, feed consumption and an increase in feed conversion ratio. Aflatoxin was also responsible for significant blood parameter, β-carotin, and also a significant (P<0.05 increase in caecal lesion scores, mortality, alkaline phosphatase level and relative liver weight, while they showed significant (P<0.05 decrease in bursal and thymus indexes in comparison with injected groups with E-tenella sporulated oocysts alone. The study approved that the groups maintained on mycofix plus 3.0 (0.25% and contaminated with aflatoxin 3.5 mg/kg, revealed a positive noticeable effects in amelioration on BWG, feed consumption and feed conversion, blood parameter, β-carotin, alkaline phosphatase level, relative liver weight, bursal and

  12. The Emerging Role of TLR and Innate Immunity in Cardiovascular Disease

    Directory of Open Access Journals (Sweden)

    Rolf Spirig

    2012-01-01

    Full Text Available Cardiovascular disease is a complex disorder involving multiple pathophysiological processes, several of which involve activation of toll-like receptors (TLRs of the innate immune system. As sentinels of innate immunity TLRs are nonclonally germline-encoded molecular pattern recognition receptors that recognize exogenous as well as tissue-derived molecular dangers signals promoting inflammation. In addition to their expression in immune cells, TLRs are found in other tissues and cell types including cardiomyocytes, endothelial and vascular smooth muscle cells. TLRs are differentially regulated in various cell types by several cardiovascular risk factors such as hypercholesterolemia, hyperlipidemia, and hyperglycemia and may represent a key mechanism linking chronic inflammation, cardiovascular disease progression, and activation of the immune system. Modulation of TLR signaling by specific TLR agonists or antagonists, alone or in combination, may be a useful therapeutic approach to treat various cardiovascular inflammatory conditions such as atherosclerosis, peripheral arterial disease, secondary microvascular complications of diabetes, autoimmune disease, and ischemia reperfusion injury. In this paper we discuss recent developments and current evidence for the role of TLR in cardiovascular disease as well as the therapeutic potential of various compounds on inhibition of TLR-mediated inflammatory responses.

  13. TLR4 and NKT cell synergy in immunotherapy against visceral leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Subir Karmakar

    Full Text Available NKT cells play an important role in autoimmune diseases, tumor surveillance, and infectious diseases, providing in most cases protection against infection. NKT cells are reactive to CD1d presented glycolipid antigens. They can modulate immune responses by promoting the secretion of type 1, type 2, or immune regulatory cytokines. Pathogen-derived signals to dendritic cells mediated via Toll like Receptors (TLR can be modulated by activated invariant Natural Killer T (iNKT cells. The terminal β-(1-4-galactose residues of glycans can modulate host responsiveness in a T helper type-1 direction via IFN-γ and TLRs. We have attempted to develop a defined immunotherapeutic, based on the cooperative action of a TLR ligand and iNKT cell using a mouse model of visceral leishmaniasis. We evaluated the anti-Leishmania immune responses and the protective efficacy of the β-(1-4-galactose terminal NKT cell ligand glycosphingophospholipid (GSPL antigen of L. donovani parasites. Our results suggest that TLR4 can function as an upstream sensor for GSPL and provoke intracellular inflammatory signaling necessary for parasite killing. Treatment with GSPL was able to induce a strong effective T cell response that contributed to effective control of acute parasite burden and led to undetectable parasite persistence in the infected animals. These studies for the first time demonstrate the interactions between a TLR ligand and iNKT cell activation in visceral leishmaniasis immunotherapeutic.

  14. In situ TLR2 and TLR4 expression in a murine model of mycetoma caused by Nocardia brasiliensis.

    Science.gov (United States)

    Millán-Chiu, Blanca Edith; Hernández-Hernández, Francisca; Pérez-Torres, Armando; Méndez-Tovar, Luis Javier; López-Martínez, Rubén

    2011-04-01

    Actinomycetoma caused by Nocardia brasiliensis is a common disease in tropical regions. This ailment is characterized by a localized chronic inflammation that mainly affects the lower limbs. Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns, inducing the production of proinflammatory mediators. The role of TLRs in the immune response against N. brasiliensis is unknown. The aim of this work was to locate and quantify in a murine model the expression of TLR2 and TLR4 in the infection site using reverse transcription-PCR and immunohistochemistry. The results showed that TLR2 expression increased in the infected tissue, whereas TLR4 expression decreased. The presence of TLR2 and TLR4 was demonstrated in different cell populations throughout the chronic infectious process. In the early stages of this process, TLR2 was expressed in neutrophils and macrophages in direct contact with the inoculum, whereas TLR4 was observed in mast cells. In the advanced stages of the infection, TLR2 was expressed in foam cells and fibroblasts and was likely associated with bacterial containment, while TLR4 was downregulated, probably resulting in an imbalance between the host immune response and the bacterial load that favoured chronic disease. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  15. Coxiella burnetii lipopolysaccharide blocks p38α-MAPK activation through the disruption of TLR-2 and TLR-4 association

    Directory of Open Access Journals (Sweden)

    Filippo eConti

    2015-01-01

    Full Text Available To survive in macrophages, Coxiella burnetii hijacks the activation pathway of macrophages. Recently, we have demonstrated that C. burnetii, via its lipopolysaccharide (LPS, avoids the activation of p38α-MAPK through an antagonistic engagement of Toll-like receptor (TLR-4. We investigated the fine-tuned mechanism leading to the absence of activation of the p38α-MAPK despite TLR-4 engagement. In macrophages challenged with Escherichia coli LPS or with the LPS from the avirulent variants of C. burnetii, TLR-4 and TLR-2 co-immunoprecipitated. This association was absent in cells challenged by the LPS of pathogenic C. burnetii. The disruption makes TLRs unable to signal during the recognition of the LPS of pathogenic C. burnetii. The disruption of TLR-2 and TLR-4 was induced by the re-organization of the macrophage cytoskeleton by C. burnetii LPS. Interestingly, blocking the actin cytoskeleton re-organization relieved the disruption of the association TLR-2/TLR-4 by pathogenic C. burnetii and rescued the p38α-MAPK activation by C. burnetii. We elucidated an unexpected mechanism allowing pathogenic C. burnetii to avoid activating macrophages by the disruption of the TLR-2 and TLR-4 association.

  16. Effects of dietary supplementation with phytonutrients on vaccine-stimulated immunity against infection with Eimeria tenella.

    Science.gov (United States)

    Lee, Sung Hyen; Lillehoj, Hyun S; Jang, Seung I; Lee, Kyung Woo; Bravo, David; Lillehoj, Erik P

    2011-09-27

    Two phytonutrient mixtures, VAC (carvacrol, cinnamaldehyde, and Capsicum oleoresin), and MC (Capsicum oleoresin and turmeric oleoresin), were evaluated for their effects on chicken immune responses following immunization with an Eimeria profilin protein. Chickens were fed with a non-supplemented diet, or with VAC- or MC-supplemented diets, immunized with profilin, and orally challenged with virulent oocysts of Eimeria tenella. Immunity against infection was evaluated by body weight, fecal oocyst shedding, profilin antibody levels, lymphocyte recall responses, cytokine expression, and lymphocyte subpopulations. Following immunization and infection, chickens fed the VAC- or MC-supplemented diets showed increased body weights, greater profilin antibody levels, and/or greater lymphocyte proliferation compared with non-supplemented controls. Prior to Eimeria infection, immunized chickens on the MC-supplemented diet showed reduced IFN-γ and IL-6 levels, but increased expression of TNFSF15, compared with non-supplemented controls. Post-infection levels of IFN-γ and IL-6 were increased, while IL-17F transcripts were decreased, with MC-supplementation. For VAC-supplemented diets, decreased IL-17F and TNFSF15 levels were observed only in infected chickens. Finally, immunized chickens fed the MC-supplemented diet exhibited increased MHC class II(+), CD4(+), CD8(+), TCR1+, or TCR2(+) T cells compared with nonsupplemented controls. Animals on the VAC-containing diet only displayed an increase in K1(+) macrophages. In conclusion, dietary supplementation with VAC or MC alters immune parameters following recombinant protein vaccination against avian coccidiosis. Published by Elsevier B.V.

  17. Activation of autoreactive B cells by endogenous TLR7 and TLR3 RNA ligands.

    Science.gov (United States)

    Green, Nathaniel M; Moody, Krishna-Sulayman; Debatis, Michelle; Marshak-Rothstein, Ann

    2012-11-16

    The key step in the activation of autoreactive B cells is the internalization of nucleic acid containing ligands and delivery of these ligands to the Toll-like Receptor (TLR) containing endolysosomal compartment. Ribonucleoproteins represent a large fraction of autoantigens in systemic autoimmune diseases. Here we demonstrate that many uridine-rich mammalian RNA sequences associated with common autoantigens effectively activate autoreactive B cells. Priming with type I IFN increased the magnitude of activation, and the range of which RNAs were stimulatory. A subset of RNAs that contain a high degree of self-complementarity also activated B cells through TLR3. For the RNA sequences that activated predominantly through TLR7, the activation is proportional to uridine-content, and more precisely defined by the frequency of specific uridine-containing motifs. These results identify parameters that define specific mammalian RNAs as ligands for TLRs.

  18. TLR receptors in laryngeal carcinoma - immunophenotypic, molecular and functional studies.

    Directory of Open Access Journals (Sweden)

    Mirosław Szczepański

    2011-04-01

    Full Text Available Toll-like receptors (TLRs have been shown to play crucial role in the recognition of unicellular pathogens. We have shown the expression of three TLRs on tumor cells of human laryngeal carcinoma by means of immunohistochemistry. In the current study we searched presence of TLR1-10 on protein and molecular level in larynx carcinoma cell lines and the impact of respective TLR ligands on TLR expression. Larynx carcinoma cell lines have been used. Cell were subjected to immunocytochemistry. RNA isolated from the cells was tested by RT-PCR. Cells were cultured in the presence of respective TLR ligands. Cells than were harvested and subjected to flow cytometry, using anti TLR1-10 Moabs. The cells were evaluated of membrane and cytoplasmic cell staining. TLR reactivity varied in individual cell lines. RT-PCR allowed to show mRNA for all TLRs tested. After short-term cell culture each cell line exhibited distinct pattern of expression of TLRs following interaction with respective ligand. Cytoplasmic TLR staining had usually higher MFI value than membrane one, but after culture with ligand it became reversed. TLRs 7 and 9 showed highest expression in the majority of tumor cells tested. In conclusion, larynx carcinoma cell lines exhibit rather universal expression of TLRs, both on protein and molecular level. Culture of TLR expressing tumor cells with ligands points out for potential reactivity of tumor cells with TLR agonists, what may have therapeutic implications.

  19. Otitis media induced by peptidoglycan-polysaccharide (PGPS) in TLR2-deficient (Tlr2(-/-)) mice for developing drug therapy.

    Science.gov (United States)

    Zhang, Xiaolin; Zheng, Tihua; Sang, Lu; Apisa, Luke; Zhao, Hongchun; Fu, Fenghua; Wang, Qingzhu; Wang, Yanfei; Zheng, Qingyin

    2015-10-01

    Toll like receptor 2 (TLR2) signaling can regulate the pathogenesis of otitis media (OM). However, the precise role of TLR2 signaling in OM has not been clarified due to the lack of an optimal animal model. Peptidoglycan-polysaccharide (PGPS) of the bacterial cell wall can induce inflammation by activating the TLR2 signaling. This study aimed at examining the pathogenic characteristics of OM induced by PGPS in Tlr2(-/-) mice, and the potential therapeutic effect of sodium aescinate (SA) in this model. Wild-type (WT) and Tlr2(-/-) mice were inoculated with streptococcal PGPS into their middle ears (MEs) and treated intravenously with vehicle or SA daily beginning at 3days prior to PGPS for 6 consecutive days. The pathologic changes of individual mice were evaluated longitudinally. In comparison with WT mice, Tlr2(-/-) mice were susceptible to PGPS-induced OM. Tlr2(-/-) mice displayed greater hearing loss, tympanic membrane damage, ME mucosal thickening, longer inflammation state, cilia and goblet cell loss. SA-treatment decreased neutrophil infiltration, modulated TLR2-related gene expression and improved ciliary organization. PGPS induced a relatively stable OM in Tlr2(-/-) mice, providing a new model for OM research. Treatment with SA mitigated the pathogenic damage in the ME and may be valuable for intervention of OM. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Polymorphisms in the Tlr4 and Tlr5 Gene Are Significantly Associated with Inflammatory Bowel Disease in German Shepherd Dogs

    Science.gov (United States)

    Kathrani, Aarti; House, Arthur; Catchpole, Brian; Murphy, Angela; German, Alex; Werling, Dirk; Allenspach, Karin

    2010-01-01

    Inflammatory bowel disease (IBD) is considered to be the most common cause of vomiting and diarrhoea in dogs, and the German shepherd dog (GSD) is particularly susceptible. The exact aetiology of IBD is unknown, however associations have been identified between specific single-nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) and human IBD. However, to date, no genetic studies have been undertaken in canine IBD. The aim of this study was to investigate whether polymorphisms in canine TLR 2, 4 and 5 genes are associated with IBD in GSDs. Mutational analysis of TLR2, TLR4 and TLR5 was performed in 10 unrelated GSDs with IBD. Four non-synonymous SNPs (T23C, G1039A, A1571T and G1807A) were identified in the TLR4 gene, and three non-synonymous SNPs (G22A, C100T and T1844C) were identified in the TLR5 gene. The non-synonymous SNPs identified in TLR4 and TLR5 were evaluated further in a case-control study using a SNaPSHOT multiplex reaction. Sequencing information from 55 unrelated GSDs with IBD were compared to a control group consisting of 61 unrelated GSDs. The G22A SNP in TLR5 was significantly associated with IBD in GSDs, whereas the remaining two SNPs were found to be significantly protective for IBD. Furthermore, the two SNPs in TLR4 (A1571T and G1807A) were in complete linkage disequilibrium, and were also significantly associated with IBD. The TLR5 risk haplotype (ACC) without the two associated TLR4 SNP alleles was significantly associated with IBD, however the presence of the two TLR4 SNP risk alleles without the TLR5 risk haplotype was not statistically associated with IBD. Our study suggests that the three TLR5 SNPs and two TLR4 SNPs; A1571T and G1807A could play a role in the pathogenesis of IBD in GSDs. Further studies are required to confirm the functional importance of these polymorphisms in the pathogenesis of this disease. PMID:21203467

  1. Polymorphisms in the TLR4 and TLR5 gene are significantly associated with inflammatory bowel disease in German shepherd dogs.

    Science.gov (United States)

    Kathrani, Aarti; House, Arthur; Catchpole, Brian; Murphy, Angela; German, Alex; Werling, Dirk; Allenspach, Karin

    2010-12-23

    Inflammatory bowel disease (IBD) is considered to be the most common cause of vomiting and diarrhoea in dogs, and the German shepherd dog (GSD) is particularly susceptible. The exact aetiology of IBD is unknown, however associations have been identified between specific single-nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) and human IBD. However, to date, no genetic studies have been undertaken in canine IBD. The aim of this study was to investigate whether polymorphisms in canine TLR 2, 4 and 5 genes are associated with IBD in GSDs. Mutational analysis of TLR2, TLR4 and TLR5 was performed in 10 unrelated GSDs with IBD. Four non-synonymous SNPs (T23C, G1039A, A1571T and G1807A) were identified in the TLR4 gene, and three non-synonymous SNPs (G22A, C100T and T1844C) were identified in the TLR5 gene. The non-synonymous SNPs identified in TLR4 and TLR5 were evaluated further in a case-control study using a SNaPSHOT multiplex reaction. Sequencing information from 55 unrelated GSDs with IBD were compared to a control group consisting of 61 unrelated GSDs. The G22A SNP in TLR5 was significantly associated with IBD in GSDs, whereas the remaining two SNPs were found to be significantly protective for IBD. Furthermore, the two SNPs in TLR4 (A1571T and G1807A) were in complete linkage disequilibrium, and were also significantly associated with IBD. The TLR5 risk haplotype (ACC) without the two associated TLR4 SNP alleles was significantly associated with IBD, however the presence of the two TLR4 SNP risk alleles without the TLR5 risk haplotype was not statistically associated with IBD. Our study suggests that the three TLR5 SNPs and two TLR4 SNPs; A1571T and G1807A could play a role in the pathogenesis of IBD in GSDs. Further studies are required to confirm the functional importance of these polymorphisms in the pathogenesis of this disease.

  2. Desert dust induces TLR signaling to trigger Th2-dominant lung allergic inflammation via a MyD88-dependent signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    He, Miao, E-mail: hemiao@mail.cmu.edu.cn [Environment and Non-communicable Disease Research Center, School of Public Health, China Medical University, Shenyang 110122 (China); Ichinose, Takamichi, E-mail: ichinose@oita-nhs.ac.jp [Department of Health Sciences, Oita University of Nursing and Health Sciences, Oita 870-1201 (Japan); Song, Yuan; Yoshida, Yasuhiro [Department of Immunology and Parasitology, School of Medicine, University of Occupational and Environmental Health, Fukuoka 807-8555 (Japan); Bekki, Kanae [Department of Environmental Health, National Institute of Public Health, Saitama 351-0197 (Japan); Arashidani, Keiichi [Department of Immunology and Parasitology, School of Medicine, University of Occupational and Environmental Health, Fukuoka 807-8555 (Japan); Yoshida, Seiichi [Department of Health Sciences, Oita University of Nursing and Health Sciences, Oita 870-1201 (Japan); Nishikawa, Masataka [Environmental Chemistry Division, National Institute for Environmental Studies, Ibaraki 305-8506 (Japan); Takano, Hirohisa [Environmental Health Division, Department of Environmental Engineering, Graduate School of Engineering, Kyoto University, Kyoto 615-8530 (Japan); Shibamoto, Takayuki [Department of Environmental Toxicology, University of California, Davis, CA 95616, USA. (United States); Sun, Guifan [Environment and Non-communicable Disease Research Center, School of Public Health, China Medical University, Shenyang 110122 (China)

    2016-04-01

    Asian sand dust (ASD) is known to exacerbate asthma, although its mechanism is not yet well understood. In this study, when the effects on inflammatory response by LPS present in ASD was investigated by measuring the gene expression of cytokines and chemokines in RAW264.7 cells treated with ASD and/or polymyxin B (PMB), the ASD effects were attenuated by PMB, but not completely. When an in vitro study was performed using bone marrow-derived macrophages (BMDMs) from WT, TLR2{sup −/−}, TLR4{sup −/−}, and MyD88{sup −/−} BALB/c mice and BMDMs from WT, TLR2{sup −/−}, TLR4{sup −/−}, TLR2/4{sup −/−}, TLR7/9{sup −/−}, and MyD88{sup −/−} C57BL/6J mice, cytokine (IL-6, IL-12) production in BMDMs was higher in ASD-stimulated TLR2{sup −/−} cells than in TLR4{sup −/−} cells, whereas it was lower or undetectable in TLR2/4{sup −/−} and MyD88{sup −/−} cells. These results suggest that ASD causes cytokine production predominantly in a TLR4/MyD88-dependent pathway. When WT and TLRs 2{sup −/−}, 4{sup −/−}, and MyD88{sup −/−} BALB/c mice were intratracheally challenged with OVA and/or ASD, ASD caused exacerbation of lung eosinophilia along with Th2 cytokine and eosinophil-relevant chemokine production. Serum OVA-specific IgE and IgG1 similar to WT was observed in TLRs 2{sup −/−}, 4{sup −/−} mice, but not in MyD88{sup −/−} mice. The Th2 responses in TLR2{sup −/−} mice were attenuated remarkably by PMB. These results indicate that ASD exacerbates lung eosinophilia in a MyD88-dependent pathway. TLRs 2 and 4 signaling may be important in the increase in lung eosinophilia. Also, the TLR4 ligand LPS and TLR2 ligand like β-glucan may be strong candidates for exacerbation of lung eosinophilia. - Highlights: • ASD enhanced Th2 response in TLR2{sup −/−}, TLR4{sup −/−} and WT mice, but not in MyD88{sup −/−}. • Th2 responses in TLR2{sup −/−} mice were attenuated by LPS inhibitor polymyxin B. • TLR2

  3. Desert dust induces TLR signaling to trigger Th2-dominant lung allergic inflammation via a MyD88-dependent signaling pathway

    International Nuclear Information System (INIS)

    He, Miao; Ichinose, Takamichi; Song, Yuan; Yoshida, Yasuhiro; Bekki, Kanae; Arashidani, Keiichi; Yoshida, Seiichi; Nishikawa, Masataka; Takano, Hirohisa; Shibamoto, Takayuki; Sun, Guifan

    2016-01-01

    Asian sand dust (ASD) is known to exacerbate asthma, although its mechanism is not yet well understood. In this study, when the effects on inflammatory response by LPS present in ASD was investigated by measuring the gene expression of cytokines and chemokines in RAW264.7 cells treated with ASD and/or polymyxin B (PMB), the ASD effects were attenuated by PMB, but not completely. When an in vitro study was performed using bone marrow-derived macrophages (BMDMs) from WT, TLR2 −/− , TLR4 −/− , and MyD88 −/− BALB/c mice and BMDMs from WT, TLR2 −/− , TLR4 −/− , TLR2/4 −/− , TLR7/9 −/− , and MyD88 −/− C57BL/6J mice, cytokine (IL-6, IL-12) production in BMDMs was higher in ASD-stimulated TLR2 −/− cells than in TLR4 −/− cells, whereas it was lower or undetectable in TLR2/4 −/− and MyD88 −/− cells. These results suggest that ASD causes cytokine production predominantly in a TLR4/MyD88-dependent pathway. When WT and TLRs 2 −/− , 4 −/− , and MyD88 −/− BALB/c mice were intratracheally challenged with OVA and/or ASD, ASD caused exacerbation of lung eosinophilia along with Th2 cytokine and eosinophil-relevant chemokine production. Serum OVA-specific IgE and IgG1 similar to WT was observed in TLRs 2 −/− , 4 −/− mice, but not in MyD88 −/− mice. The Th2 responses in TLR2 −/− mice were attenuated remarkably by PMB. These results indicate that ASD exacerbates lung eosinophilia in a MyD88-dependent pathway. TLRs 2 and 4 signaling may be important in the increase in lung eosinophilia. Also, the TLR4 ligand LPS and TLR2 ligand like β-glucan may be strong candidates for exacerbation of lung eosinophilia. - Highlights: • ASD enhanced Th2 response in TLR2 −/− , TLR4 −/− and WT mice, but not in MyD88 −/− . • Th2 responses in TLR2 −/− mice were attenuated by LPS inhibitor polymyxin B. • TLR2 and TLR4 signaling is important in allergic lung disease aggravation by ASD. • MyD88 is the key

  4. TLR-2 and TLR-4 expression in monocytes of newborns with late-onset sepsis,

    Directory of Open Access Journals (Sweden)

    Ana C.C. Redondo

    2014-09-01

    Full Text Available Objetivos: Analisar a expressão dos TLR-2 e TLR-4 em monócitos de recém-nascidos com sepse tardia. Métodos: Trata-se de um estudo prospectivo com 27 recém-nascidos a termo entre 8 e 29 dias de vida com diagnóstico clínico e laboratorial de sepse tardia dos quais dez (37% apresentaram cultura positiva. As citocinas foram determinadas por teste de CBA em sangue periférico enquanto que a expressão e MFI (mediana de intensidade de fluorescência dos TLR-2 e TLR-4 foi determinado por imunofenotipagem em monócitos de sangue periférico total através de análise pelo citômetro de fluxo BD FACSDiva. O grupo usado para comparação foi de adultos saudáveis. Resultados: Microrganismos foram identificados em 37% dos pacientes e estes juntamente com os pacientes com sepse clínica tiveram níveis elevados de citocinas pró-inflamatórias (IL-8, IL-6, IL-1β e de citocina anti-inflamatória (IL-10 corroborando o processo inflamatório/infeccioso. No monócito, a frequência de expressão do TLR-4 foi mais elevada (p = 0,01. Conclusões: Este estudo analisou a resposta imune inata no recém-nascido com sepse. Recémnascidos sépticos que dependem quase exclusivamente do sistema imune inato apresentaram pouca resposta in vivo na ativação de monócitos o que sugere uma resposta imune deficiente e maior susceptibilidade à infecção.

  5. DMPD: TLR signaling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 2007 Feb 1. (.png) (.svg) (.html) (.csml) Show TLR signaling. PubmedID 17275323 Title TLR signaling. Author...s Kawai T, Akira S. Publication Semin Immunol. 2007 Feb;19(1):24-32. Epub 2007 Feb 1. Pathway - PNG File (.png) SVG File (.svg) HTML... File (.html) CSML File (.csml) Open .csml file with CIOP

  6. TLR2 deficiency aggravates lung injury caused by mechanical ventilation

    NARCIS (Netherlands)

    Kuipers, Maria Theresa; Jongsma, Geartsje; Hegeman, Maria A; Tuip-de Boer, Anita M; Wolthuis, Esther K; Choi, Goda; Bresser, Paul; van der Poll, Tom; Schultz, Marcus J; Wieland, Catharina W

    Innate immunity pathways are found to play an important role in ventilator-induced lung injury. We analyzed pulmonary expression of Toll-like receptor 2 (TLR2) in humans and mice and determined the role of TLR2 in the pathogenesis of ventilator-induced lung injury in mice. Toll-like receptor 2 gene

  7. Analysis of TLR polymorphisms in typhoid patients and ...

    African Journals Online (AJOL)

    Ilakkia Sivaji

    2016-01-20

    Jan 20, 2016 ... implicated the genetic variations (polymorphisms) in TLR genes to influence the host susceptibility to infectious diseases. However, the available literature on TLR polymorphism and susceptibility to typhoid fever is unclear. Aim: This study aimed to investigate the polymorphism of TLRs 1, 2, 4 and 5 in ...

  8. Meat and fiber intake and interaction with pattern recognition receptors (TLR1, TLR2, TLR4, and TLR10) in relation to colorectal cancer in a Danish prospective, case-cohort study.

    Science.gov (United States)

    Kopp, Tine Iskov; Vogel, Ulla; Tjonneland, Anne; Andersen, Vibeke

    2018-03-01

    Meat and dietary fiber are associated with increased and decreased risk of colorectal cancer (CRC), respectively. Toll-like receptors (TLRs) regulate the intestinal immune response in a complex interplay between the mucosal epithelium and the microbiota and may therefore be important modulators of diet-induced CRC together with other inflammatory mediators. Our aim was to investigate the association between functional TLR polymorphisms and risk of CRC and the interaction with dietary factors. Additionally, interactions with previously studied polymorphisms in IL10, IL1B, PTGS2, and NFKB1 were assessed in order to examine possible biological pathways in meat-induced CRC. A nested case-cohort study of 897 CRC cases and 1689 randomly selected participants from the Danish prospective "Diet, Cancer and Health" study encompassing 57,053 persons was performed using Cox proportional hazard models and the likelihood ratio test. We found associations between polymorphisms in TLR2 (P = 0.018) and TLR4 (P = 0.044) and risk of CRC per se, interactions between intake of red and processed meat (10 g/d) and polymorphisms in TLR1 (P-interaction = 0.032) and TLR10 (P-interaction = 0.026 and 0.036), and intake of cereals (50 g/d) and TLR4 (P-interaction = 0.044) in relation to risk of CRC. Intake of red and processed meat also interacted with combinations of polymorphisms in TLR1 and TLR10 and polymorphisms in NFKB1, IL10, IL1B, and PTGS2 (P-interaction; TLR1/rs4833095 × PTGS2/rs20417 = 0.021, TLR10/rs11096955 × IL10/rs3024505 = 0.047, TLR10/rs11096955 × PTGS2/rs20417 = 0.017, TLR10/rs4129009 × NFKB1/rs28362491 = 0.027, TLR10/rs4129009 × IL1B/rs4848306 = 0.020, TLR10/rs4129009 × IL1B/rs1143623 = 0.021, TLR10/rs4129009 × PTGS2/rs20417 = 0.027), whereas intake of dietary fiber (10 g/d) interacted with combinations of polymorphisms in TLR4, IL10, and PTGS2 (P-interaction; TLR4/rs1554973 × IL10/rs3024505 = 0.0012, TLR4/rs1554973 × PTGS2/rs20417 = 0.0041, TLR4/rs1554973 × PTGS

  9. The immunogenicity of Eimeria tenella sporozoite proteins and living oocyst vaccines in broilersImunogenicidade de vacina com proteínas de esporozoítos e oocistos vivos de Eimeria tenella em frangos

    Directory of Open Access Journals (Sweden)

    Odilon Vidotto

    2012-02-01

    Full Text Available The purpose of the present study was to evaluate the immunity of broilers inoculated with sporulated oocysts and sporozoite proteins of Eimeria tenella against challenge with homologous infectives oocysts. Broiler chickens of Hubbard strain, females, coccidian-free, were kept in wire cages and inoculated on the third day (day 0. Three treatments were used: T1, the negative control; T2, received 500 sporulated oocysts by gavage; T3, positive control; T4, received 50 ?g of sporozoite protein with Quil A; and T5, received Quil A without sporozoite protein and PBS, the last two protocols were administered via nasal route on days 0, 7, and 21. On the 31st day, all groups, with the exception of T1, were challenged with homologous virulent strain of E. tenella at the dose of 8.0×104 oocysts. Immunogenicity was assessed by carotenoids, ELISA assay, histopathological analysis, oocysts count and lesion score. Antibody kinetics were measured weekly and showed a gradual increase in levels of immunoglobulin for treatment T2 and T4, reaching a peak on day 21. Based on the parameters evaluated, a total protecting immunological effect for the infectant oocysts vaccine (T2 and partial protection for the sporozoite protein vaccine (T4 against homologous virulent strain challenge were observed. O objetivo do presente estudo foi avaliar a imunidade de frangos de corte inoculados com oocistos esporulados e proteínas de esporozoítos de Eimeria tenella utilizando um desafio com oocistos esporulados homólogos. Frangos de corte da linhagem Hubbard, fêmeas, livres de coccidiose, foram mantidos em gaiolas de arame e inoculados no terceiro dia (dia 0. O delineamento experimental consistiu de cinco tratamentos com três repetições: T1- controle negativo; T2- recebeu 500 oocistos esporulados por gavagem; T3- controle positivo; T4- receberam 50 ?g de proteína de esporozoítos adicionados a Quil-A, e finalmente o T5- que recebeu apenas Quil A e PBS, os últimos dois

  10. Up-regulation of TLR2 and TLR4 in high mobility group Box1-stimulated macrophages in pulpitis patients

    Science.gov (United States)

    Mahmoudi, Javad; Sabermarouf, Babak; Baradaran, Behzad; Sadat-Hatamnezhad, Leila; Shotorbani, Siamak Sandoghchian

    2017-01-01

    Objective(s): High Mobility Group Box1 (HMGB1) is a nonhistone, DNA-binding protein that serves a crucial role in regulating gene transcription and is involved in a variety of proinflammatory, extracellular activities. The aim of this study was to explore whether HMGB1 stimulation can up-regulate the expression of Toll-like Receptor 2 (TLR2) and Toll-like Receptor 4 (TLR4) on macrophages from pulpitis and to clarify the subsequent events involving Th17 cells and Th17 cell-associated cytokine changes. Materials and Methods: Having prepared dental pulp tissues of pulpitis and healthy controls, macrophage were isolated and cultured. Macrophages were thereafter stimulated by HMGB1 time course. RT-QPCR, flowcytometer, immunofluorescence, Western blotting, and ELISA techniques were used in the present research. Results: Our results showed that the expression of TLR2 and TLR4 on macrophages stimulated with HMGB1 increased in pulpitis compared with controls (macrophages without HMGB1 stimulation) with a statistical significance (Ppulpitis increased, and NF-kB, the downstream target of TLR2 and TLR4, also showed a marked elevation after macrophages’ stimulation by HMGB1. Conclusion: The evidence from the present study suggests that the enhanced TLR2 and TLR4 pathways and Th17 cell polarization may be due to HMGB1 stimulation in pulpitis. PMID:28293399

  11. Generation of anti-TLR2 intrabody mediating inhibition of macrophage surface TLR2 expression and TLR2-driven cell activation

    OpenAIRE

    Kirschning, Carsten J; Dreher, Stefan; Maa?, Bj?rn; Fichte, Sylvia; Schade, Jutta; K?ster, Mario; Noack, Andreas; Lindenmaier, Werner; Wagner, Hermann; B?ldicke, Thomas

    2010-01-01

    Abstract Background Toll-like receptor (TLR) 2 is a component of the innate immune system and senses specific pathogen associated molecular patterns (PAMPs) of both microbial and viral origin. Cell activation via TLR2 and other pattern recognition receptors (PRRs) contributes to sepsis pathology and chronic inflammation both relying on overamplification of an immune response. Intracellular antibodies expressed and retained inside the endoplasmatic reticulum (ER-intrabodies) are applied to blo...

  12. Ursolic acid isolated from Uncaria rhynchophylla activates human dendritic cells via TLR2 and/or TLR4 and induces the production of IFN-gamma by CD4+ naïve T cells.

    Science.gov (United States)

    Jung, Tae-Young; Pham, Thanh Nhan Nguyen; Umeyama, Akemi; Shoji, Noboru; Hashimoto, Toshihiro; Lee, Je-Jung; Takei, Masao

    2010-09-25

    Ursolic acid is triterpene isolated from Uncaria rhynchophylla and is a pharmacologically active substance. The induction of dendritic cell maturation is critical for the induction of Ag-specific T-lymphocyte response and may be essential for the development of human vaccine relying on T cell immunity. In this study, we investigated that the effect of Ursolic acid on the phenotypic and functional maturation of human monocyte-derived dendritic cells in vitro. Dendritic cells harvested on day 8 were examined using functional assay. The expression levels of CD1a, CD80, CD83, CD86, HLA-DR and CCR7 on Ursolic acid-primed dendritic cells was slightly enhanced. Ursolic acid dose-dependently enhanced the T cell stimulatory capacity in an allogeneic mixed lymphocyte reaction, as measured by T cell proliferation. The production of IL-12p70 induced by Ursolic acid-primed dendritic cells was inhibited by the anti-Toll-like receptor-2 (TLR2) mAb and anti-TLR4 mAb. Moreover, Ursolic acid-primed dendritic cells expressed levels of mRNA coding for both TLR2 and TLR4. The majority of cells produced considerable interferon-gamma (IFN-gamma), but also small amounts of interleukin (IL-4)-4. Ursolic acid-primed dendritic cells have an intermediate migratory capacity towards CCL19 and CCL21. These results suggest that Ursolic acid modulates human dendritic cells function in a fashion that favors Th1 polarization via the activation of IL-12p70 dependent on TLR2 and/or TLR4, and may be used on dendritic cells-based vaccines for cancer immunotherapy. 2010 Elsevier B.V. All rights reserved.

  13. Microglia are required for astroglial toll-like receptor 4 response and for optimal TLR2 and TLR3 response

    DEFF Research Database (Denmark)

    Holm, Thomas H; Draeby, Dina; Owens, Trevor

    2012-01-01

    Within the central nervous system, astrocytes and microglia are the primary responders to endogenous ligands released upon injury and stress, as well as to infectious pathogens. Toll-like receptors (TLRs) are implicated in recognition of both types of stimulus. Whether astrocytes respond as stron......Within the central nervous system, astrocytes and microglia are the primary responders to endogenous ligands released upon injury and stress, as well as to infectious pathogens. Toll-like receptors (TLRs) are implicated in recognition of both types of stimulus. Whether astrocytes respond...... astrocytes from mixed glial cultures and measured their response to TLR agonists. Our results show that the response of astrocytes to TLR2 and TLR3 agonists is greatly enhanced by, and response to TLR4 agonists is completely dependent on, the presence of functional microglia. In the case of the TLR4 response...

  14. Activation of TLR2 and TLR6 by Dengue NS1 Protein and Its Implications in the Immunopathogenesis of Dengue Virus Infection.

    Directory of Open Access Journals (Sweden)

    Jincheng Chen

    2015-07-01

    Full Text Available Dengue virus (DV infection is the most prevalent mosquito-borne viral disease and its manifestation has been shown to be contributed in part by the host immune responses. In this study, pathogen recognition receptors, Toll-like receptor (TLR 2 and TLR6 were found to be up-regulated in DV-infected human PBMC using immunofluorescence staining, flow cytometry and Western blot analyses. Using ELISA, IL-6 and TNF-α, cytokines downstream of TLR2 and TLR6 signaling pathways were also found to be up-regulated in DV-infected PBMC. IL-6 and TNF-α production by PBMC were reduced when TLR2 and TLR6 were blocked using TLR2 and TLR6 neutralizing antibodies during DV infection. These results suggested that signaling pathways of TLR2 and TLR6 were activated during DV infection and its activation contributed to IL-6 and TNF-α production. DV NS1 protein was found to significantly increase the production of IL-6 and TNF-α when added to PBMC. The amount of IL-6 and TNF-α stimulated by DV NS1 protein was reduced when TLR2 and TLR6 were blocked, suggesting that DV NS1 protein is the viral protein responsible for the activation of TLR2 and TLR6 during DV infection. Secreted alkaline phosphatase (SEAP reporter assay was used to further confirm activation of TLR2 and TLR6 by DV NS1 protein. In addition, DV-infected and DV NS1 protein-treated TLR6-/- mice have higher survivability compared to DV-infected and DV NS1 protein-treated wild-type mice. Hence, activation of TLR6 via DV NS1 protein could potentially play an important role in the immunopathogenesis of DV infection.

  15. The attenuated inflammation of MPL is due to the lack of CD14-dependent tight dimerization of the TLR4/MD2 complex at the plasma membrane.

    Science.gov (United States)

    Tanimura, Natsuko; Saitoh, Shin-Ichiroh; Ohto, Umeharu; Akashi-Takamura, Sachiko; Fujimoto, Yukari; Fukase, Koichi; Shimizu, Toshiyuki; Miyake, Kensuke

    2014-06-01

    TLR4/MD-2 senses lipid A, activating the MyD88-signaling pathway on the plasma membrane and the TRIF-signaling pathway after CD14-mediated TLR4/MD-2 internalization into endosomes. Monophosphoryl lipid A (MPL), a detoxified derivative of lipid A, is weaker than lipid A in activating the MyD88-dependent pathway. Little is known, however, about mechanisms underlying the attenuated activation of MyD88-dependent pathways. We here show that MPL was impaired in induction of CD14-dependent TLR4/MD-2 dimerization compared with lipid A. Impaired TLR4/MD-2 dimerization decreased CD14-mediated TNFα production. In contrast, MPL was comparable to lipid A in CD14-independent MyD88-dependent TNFα production and TRIF-dependent responses including cell surface CD86 up-regulation and IFNβ induction. Although CD86 up-regulation is dependent on TRIF signaling, it was induced by TLR4/MD-2 at the plasma membrane. These results revealed that the attenuated MPL responses were due to CD14-initiated responses at the plasma membrane, but not just to responses initiated by MyD88, that is, MPL was specifically unable to induce CD14-dependent TLR4/MD-2 dimerization that selectively enhances MyD88-mediated responses at the plasma membrane. © The Japanese Society for Immunology. 2013. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Innate Immune Responses to TLR2 and TLR4 Agonists Differ between Baboons, Chimpanzees and Humans

    Science.gov (United States)

    Brinkworth, Jessica F.; Pechenkina, Ekaterina A.; Silver, Jack; Goyert, Sanna M.

    2012-01-01

    Background African catarrhine primates differ in bacterial disease susceptibility. Methods Human, chimpanzee, and baboon blood was stimulated with TLR-detected bacterial agonists and cytokine/chemokine induction assessed by real-time pcr. Results Humans and chimpanzees shared similar cytokine/chemokine responses, while baboon cytokine/chemokine induction differed. Generally, responses were agonist-independent. Conclusions These primates tend to generate species rather than agonist–specific responses to bacterial agonists. PMID:22978822

  17. A Novel Vaccine Delivery Model of the Apicomplexan Eimeria tenella Expressing Eimeria maxima Antigen Protects Chickens against Infection of the Two Parasites.

    Science.gov (United States)

    Tang, Xinming; Liu, Xianyong; Yin, Guangwen; Suo, Jingxia; Tao, Geru; Zhang, Sixin; Suo, Xun

    2017-01-01

    Vaccine delivery is critical in antigen discovery and vaccine efficacy and safety. The diversity of infectious diseases in humans and livestock has required the development of varied delivery vehicles to target different pathogens. In livestock animals, previous strategies for the development of coccidiosis vaccines have encountered several hurdles, limiting the development of multiple species vaccine formulations. Here, we describe a novel vaccine delivery system using transgenic Eimeria tenella expressing immunodominant antigens of Eimeria maxima . In this delivery system, the immune mapped protein 1 of E. maxima (EmIMP1) was delivered by the closely related species of E. tenella to the host immune system during the whole endogenous life cycle. The overexpression of the exogenous antigen did not interfere with the reproduction and immunogenicity of transgenic Eimeria . After immunization with the transgenic parasite, we detected EmIMP1's and E. maxima oocyst antigens' specific humoral and cellular immune responses. In particular, we observed partial protection of chickens immunized with transgenic E. tenella against subsequent E. maxima infections. Our results demonstrate that the transgenic Eimeria parasite is an ideal coccidia antigen delivery vehicle and represents a new type of coccidiosis vaccines. In addition, this model could potentially be used in the development of malaria live sporozoite vaccines, in which antigens from different strains can be expressed in the vaccine strain.

  18. A Novel Vaccine Delivery Model of the Apicomplexan Eimeria tenella Expressing Eimeria maxima Antigen Protects Chickens against Infection of the Two Parasites

    Science.gov (United States)

    Tang, Xinming; Liu, Xianyong; Yin, Guangwen; Suo, Jingxia; Tao, Geru; Zhang, Sixin; Suo, Xun

    2018-01-01

    Vaccine delivery is critical in antigen discovery and vaccine efficacy and safety. The diversity of infectious diseases in humans and livestock has required the development of varied delivery vehicles to target different pathogens. In livestock animals, previous strategies for the development of coccidiosis vaccines have encountered several hurdles, limiting the development of multiple species vaccine formulations. Here, we describe a novel vaccine delivery system using transgenic Eimeria tenella expressing immunodominant antigens of Eimeria maxima. In this delivery system, the immune mapped protein 1 of E. maxima (EmIMP1) was delivered by the closely related species of E. tenella to the host immune system during the whole endogenous life cycle. The overexpression of the exogenous antigen did not interfere with the reproduction and immunogenicity of transgenic Eimeria. After immunization with the transgenic parasite, we detected EmIMP1’s and E. maxima oocyst antigens’ specific humoral and cellular immune responses. In particular, we observed partial protection of chickens immunized with transgenic E. tenella against subsequent E. maxima infections. Our results demonstrate that the transgenic Eimeria parasite is an ideal coccidia antigen delivery vehicle and represents a new type of coccidiosis vaccines. In addition, this model could potentially be used in the development of malaria live sporozoite vaccines, in which antigens from different strains can be expressed in the vaccine strain. PMID:29375584

  19. Effects of TLR agonists on maturation and function of 3-day dendritic cells from AML patients in complete remission

    Directory of Open Access Journals (Sweden)

    Merk Martina

    2011-09-01

    Full Text Available Abstract Background Active dendritic cell (DC immunization protocols are rapidly gaining interest as therapeutic options in patients with acute myeloid leukemia (AML. Here we present for the first time a GMP-compliant 3-day protocol for generation of monocyte-derived DCs using different synthetic Toll-like receptor (TLR agonists in intensively pretreated patients with AML. Methods Four different maturation cocktails were compared for their impact on cell recovery, phenotype, cytokine secretion, migration, and lymphocyte activation in 20 AML patients and 25 healthy controls. Results Maturation cocktails containing the TLR7/8 agonists R848 or CL075, with and without the addition of the TLR3 agonist poly(I:C, induced DCs that had a positive costimulatory profile, secreted high levels of IL-12(p70, showed chemotaxis to CCR7 ligands, had the ability to activate NK cells, and efficiently stimulated antigen-specific CD8+ T cells. Conclusions Our results demonstrate that this approach translates into biologically improved DCs, not only in healthy controls but also in AML patients. This data supports the clinical application of TLR-matured DCs in patients with AML for activation of innate and adaptive immune responses.

  20. Microsatellite mapping of QTLs affecting resistance to coccidiosis (Eimeria tenella) in a Fayoumi x White Leghorn cross.

    Science.gov (United States)

    Pinard-van der Laan, Marie-Hélène; Bed'hom, Bertrand; Coville, Jean-Luc; Pitel, Frédérique; Feve, Katia; Leroux, Sophie; Legros, Hélène; Thomas, Aurélie; Gourichon, David; Repérant, Jean-Michel; Rault, Paul

    2009-01-20

    Avian coccidiosis is a major parasitic disease of poultry, causing severe economical loss to poultry production by affecting growth and feed efficiency of infected birds. Current control strategies using mainly drugs and more recently vaccination are showing drawbacks and alternative strategies are needed. Using genetic resistance that would limit the negative and very costly effects of the disease would be highly relevant. The purpose of this work was to detect for the first time QTL for disease resistance traits to Eimeria tenella in chicken by performing a genome scan in an F2 cross issued from a resistant Fayoumi line and a susceptible Leghorn line. The QTL analysis detected 21 chromosome-wide significant QTL for the different traits related to disease resistance (body weight growth, plasma coloration, hematocrit, rectal temperature and lesion) on 6 chromosomes. Out of these, a genome-wide very significant QTL for body weight growth was found on GGA1, five genome-wide significant QTL for body weight growth, plasma coloration and hematocrit and one for plasma coloration were found on GGA1 and GGA6, respectively. Two genome-wide suggestive QTL for plasma coloration and rectal temperature were found on GGA1 and GGA2, respectively. Other chromosme-wide significant QTL were identified on GGA2, GGA3, GGA6, GGA15 and GGA23. Parent-of-origin effects were found for QTL for body weight growth and plasma coloration on GGA1 and GGA3. Several QTL for different resistance phenotypes were identified as co-localized on the same location. Using an F2 cross from resistant and susceptible chicken lines proved to be a successful strategy to identify QTL for different resistance traits to Eimeria tenella, opening the way for further gene identification and underlying mechanisms and hopefully possibilities for new breeding strategies for resistance to coccidiosis in the chicken. From the QTL regions identified, several candidate genes and relevant pathways linked to innate immune

  1. Microsatellite mapping of QTLs affecting resistance to coccidiosis (Eimeria tenella in a Fayoumi × White Leghorn cross

    Directory of Open Access Journals (Sweden)

    Gourichon David

    2009-01-01

    Full Text Available Abstract Background Avian coccidiosis is a major parasitic disease of poultry, causing severe economical loss to poultry production by affecting growth and feed efficiency of infected birds. Current control strategies using mainly drugs and more recently vaccination are showing drawbacks and alternative strategies are needed. Using genetic resistance that would limit the negative and very costly effects of the disease would be highly relevant. The purpose of this work was to detect for the first time QTL for disease resistance traits to Eimeria tenella in chicken by performing a genome scan in an F2 cross issued from a resistant Fayoumi line and a susceptible Leghorn line. Results The QTL analysis detected 21 chromosome-wide significant QTL for the different traits related to disease resistance (body weight growth, plasma coloration, hematocrit, rectal temperature and lesion on 6 chromosomes. Out of these, a genome-wide very significant QTL for body weight growth was found on GGA1, five genome-wide significant QTL for body weight growth, plasma coloration and hematocrit and one for plasma coloration were found on GGA1 and GGA6, respectively. Two genome-wide suggestive QTL for plasma coloration and rectal temperature were found on GGA1 and GGA2, respectively. Other chromosme-wide significant QTL were identified on GGA2, GGA3, GGA6, GGA15 and GGA23. Parent-of-origin effects were found for QTL for body weight growth and plasma coloration on GGA1 and GGA3. Several QTL for different resistance phenotypes were identified as co-localized on the same location. Conclusion Using an F2 cross from resistant and susceptible chicken lines proved to be a successful strategy to identify QTL for different resistance traits to Eimeria tenella, opening the way for further gene identification and underlying mechanisms and hopefully possibilities for new breeding strategies for resistance to coccidiosis in the chicken. From the QTL regions identified, several

  2. TLR9 played a more important role than TLR2 in the combination of maltose-binding protein and BCG-induced Th1 activation.

    Science.gov (United States)

    Ni, Weihua; Wang, Fang; Liu, Guomu; Zhang, Nannan; Yuan, Hongyan; Jie, Jing; Tai, Guixiang

    2016-11-01

    Our previous study demonstrated that maltose-binding protein (MBP) combined with BCG induced synergistic mouse Th1 activation in vivo. Here, to explore the mechanism of MBP combined with BCG on Th1 activation, mouse purified CD4 + T cells were stimulated with MBP and BCG in vitro. The results showed that MBP combined with BCG synergistically increased IFN-γ production, accompanied with the upregulation of TLR2/9 expressions, suggesting that TLR2/9 were involved in the combination-induced Th1 activation. Next, TLR2 antibodies and TLR9 inhibitor were used to further analyze the effects of TLRs in Th1 activation. Results showed TLR2 antibody partly decreased MBP combined with BCG-induced IFN-γ production, MyD88 expression and IκB phosphorylation, indicating that TLR2-mediated MyD88-dependent pathway was involved in the MBP combined with BCG-induced Th1 activation. Moreover, MBP combined with BCG-induced Th1 activation was completely abrogated by TLR9 inhibitor, suggesting that TLR9-mediated MyD88-dependent pathway played a more important role than TLR2 in the combination-induced Th1 activation. Further study showed that TLR9 inhibitor downregulated TLR2 expression, suggesting that TLR9 signaling regulated TLR2 activation to favor Th1 resonse induced by MBP combined with BCG. Collectively, we demonstrated for the first time that the cross-talk of TLR2 and TLR9 triggered Th1 activation collaboratively and our findings provided valuable information about designing more effective adjuvant for cancer therapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Pathogenic strains of Acanthamoeba are recognized by TLR4 and initiated inflammatory responses in the cornea.

    Directory of Open Access Journals (Sweden)

    Hassan Alizadeh

    Full Text Available Free-living amoebae of the Acanthamoeba species are the causative agent of Acanthamoeba keratitis (AK, a sight-threatening corneal infection that causes severe pain and a characteristic ring-shaped corneal infiltrate. Innate immune responses play an important role in resistance against AK. The aim of this study is to determine if Toll-like receptors (TLRs on corneal epithelial cells are activated by Acanthamoeba, leading to initiation of inflammatory responses in the cornea. Human corneal epithelial (HCE cells constitutively expressed TLR1, TLR2, TLR3, TLR4, and TLR9 mRNA, and A. castellanii upregulated TLR4 transcription. Expression of TLR1, TLR2, TLR3, and TLR9 was unchanged when HCE cells were exposed to A. castellanii. IL-8 mRNA expression was upregulated in HCE cells exposed to A. castellanii. A. castellanii and lipopolysaccharide (LPS induced significant IL-8 production by HCE cells as measured by ELISA. The percentage of total cells positive for TLR4 was higher in A. castellanii stimulated HCE cells compared to unstimulated HCE cells. A. castellanii induced upregulation of IL-8 in TLR4 expressing human embryonic kidney (HEK-293 cells, but not TLR3 expressing HEK-293 cells. TLR4 neutralizing antibody inhibited A. castellanii-induced IL-8 by HCE and HEK-293 cells. Clinical strains but not soil strains of Acanthamoeba activated TLR4 expression in Chinese hamster corneas in vivo and in vitro. Clinical isolates but not soil isolates of Acanthamoeba induced significant (P< 0.05 CXCL2 production in Chinese hamster corneas 3 and 7 days after infection, which coincided with increased inflammatory cells in the corneas. Results suggest that pathogenic species of Acanthamoeba activate TLR4 and induce production of CXCL2 in the Chinese hamster model of AK. TLR4 may be a potential target in the development of novel treatment strategies in Acanthamoeba and other microbial infections that activate TLR4 in corneal cells.

  4. A novel CCR-2/TLR-2 triggered signaling in murine peritoneal macrophages intensifies bacterial (Staphylococcus aureus) killing by reactive oxygen species through TNF-R1.

    Science.gov (United States)

    Nandi, Ajeya; Bishayi, Biswadev

    2017-10-01

    Macrophages are remarkably versatile in their ability to recognize and respond to a wide range of stimuli by expressing a variety of surface and intracellular receptors and triggering multiple signal transduction pathways. The onset of microbial infection is primarily determined by the initial contacts made by the microbes with the host macrophages. Although there prevail a relationship between the chemokine receptor and Toll like receptors during disease, particularly TLR-2 and CCR-2 signaling interdependence on each other has not been yet investigated during acute staphylococcal infection. Thus, the present study was aimed to trace possible interaction between CCR-2 and TLR-2 in peritoneal macrophages during acute Staphylococcus aureus infection. We found that neutralization of CCR-2 attenuates TLR-2 expression and restricts S. aureus burden but TLR-2 neutralization augments CCR-2 expression in macrophages, along with compromised host-derived reactive oxygen species production. S. aureus infection to CCR-2 intact but TLR-2 neutralized macrophages triggered production of IL-1β, TNF-α, IL-6, IFN-γ, MCP-1 and expression of iNOS, TNFR-1 and GPx with concomitant decrease in IL-10 production. Further, study with NG-monomethyl-l-arginine (L-NMMA) [iNOS blocker] and buthionine sulfoximine (BSO) [GPx blocker] revealed that S. aureus infection enhanced TLR-2 expression in CCR-2 intact and TLR-2 neutralized macrophages possibly via iNOS and TNFR-1 up regulation and GPx down regulation. Overall, our data indicate that targeting CCR-2 with neutralizing antibody in the early phase of S. aureus infection could restrict excessive inflammation with less compromised bacterial killing. It certainly would be a therapeutic strategy in S. aureus induced inflammatory and infective diseases. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  5. Induction of TLR-2 and TLR-5 expression by Helicobacter pylori switches cagPAI-dependent signalling leading to the secretion of IL-8 and TNF-α.

    Directory of Open Access Journals (Sweden)

    Suneesh Kumar Pachathundikandi

    2011-05-01

    Full Text Available Helicobacter pylori is the causative agent for developing gastritis, gastric ulcer, and even gastric cancer. Virulent strains carry the cag pathogenicity island (cagPAI encoding a type-IV secretion system (T4SS for injecting the CagA protein. However, mechanisms of sensing this pathogen through Toll-like receptors (TLRs and downstream signalling pathways in the development of different pathologies are widely unclear. Here, we explored the involvement of TLR-2 and TLR-5 in THP-1 cells and HEK293 cell lines (stably transfected with TLR-2 or TLR-5 during infection with wild-type H. pylori and isogenic cagPAI mutants. H. pylori triggered enhanced TLR-2 and TLR-5 expression in THP-1, HEK293-TLR2 and HEK293-TLR5 cells, but not in the HEK293 control. In addition, IL-8 and TNF-α cytokine secretion in THP-1 cells was induced in a cagPAI-dependent manner. Furthermore, we show that HEK293 cells are not competent for the uptake of T4SS-delivered CagA, and are therefore ideally suited for studying TLR signalling in the absence of T4SS functions. HEK293 control cells, which do not induce TLR-2 and TLR-5 expression during infection, only secreted cytokines in small amounts, in agreement with T4SS functions being absent. In contrast, HEK293-TLR2 and HEK293-TLR5 cells were highly competent for inducing the secretion of IL-8 and TNF-α cytokines in a cagPAI-independent manner, suggesting that the expression of TLR-2 or TLR-5 has profoundly changed the capability to trigger pro-inflammatory signalling upon infection. Using phospho-specific antibodies and luciferase reporter assays, we further demonstrate that H. pylori induces IRAK-1 and IκB phosphorylation in a TLR-dependent manner, and this was required for activation of transcription factor NF-κB. Finally, NF-κB activation in HEK293-TLR2 and HEK293-TLR5 cells was confirmed by expressing p65-GFP which was translocated from the cytoplasm into the nucleus. These data indicate that H. pylori-induced expression

  6. Intradermally administered TLR4 agonist GLA-SE enhances the capacity of human skin DCs to activate T cells and promotes emigration of Langerhans cells

    NARCIS (Netherlands)

    Schneider, Laura P.; Schoonderwoerd, Antoinet J.; Moutaftsi, Magdalini; Howard, Randall F.; Reed, Steven G.; de Jong, Esther C.; Teunissen, Marcel B. M.

    2012-01-01

    The natural TLR4 agonist lipopolysaccharide (LPS) has notable adjuvant activity. However, it is not useful as a vaccine adjuvant due to its toxicity. Glucopyranosyl lipid A (GLA) is a synthetic derivative of the lipid A tail of LPS with limited cytotoxicity, but strong potential to induce immune

  7. Recognition of TLR2 N-Glycans: Critical Role in ArtinM Immunomodulatory Activity

    Science.gov (United States)

    da Silva, Thiago Aparecido; Ruas, Luciana Pereira; Nohara, Lilian L.; de Almeida, Igor Correia; Roque-Barreira, Maria Cristina

    2014-01-01

    TLR2 plays a critical role in the protection against Paracoccidioides brasiliensis conferred by ArtinM administration. ArtinM, a D-mannose-binding lectin from Artocarpus heterophyllus, induces IL-12 production in macrophages and dendritic cells, which accounts for the T helper1 immunity that results from ArtinM administration. We examined the direct interaction of ArtinM with TLR2using HEK293A cells transfected with TLR2, alone or in combination with TLR1 or TLR6, together with accessory proteins. Stimulation with ArtinM induced NF-κB activation and interleukin (IL)-8 production in cells transfected with TLR2, TLR2/1, or TLR2/6. Murine macrophages that were stimulated with ArtinM had augmented TLR2 mRNA expression. Furthermore, pre-incubation of unstimulated macrophages with an anti-TLR2 antibody reduced the cell labeling with ArtinM. In addition, a microplate assay revealed that ArtinM bound to TLR2 molecules that had been captured by specific antibodies from a macrophages lysate. Notably,ArtinM binding to TLR2 was selectively inhibited when the lectin was pre-incubated with mannotriose. The biological relevance of the direct interaction of ArtinM with TLR2 glycans was assessed using macrophages from TLR2-KOmice, which produced significantly lower levels of IL-12 and IL-10 in response to ArtinM than macrophages from wild-type mice. Pre-treatment of murine macrophages with pharmacological inhibitors of signaling molecules demonstrated the involvement of p38 MAPK and JNK in the IL-12 production induced by ArtinM and the involvement ofPI3K in IL-10 production. Thus, ArtinM interacts directly with TLR2 or TLR2 heterodimers in a carbohydrate recognition-dependent manner and functions as a TLR2 agonist with immunomodulatory properties. PMID:24892697

  8. Recognition of TLR2 N-glycans: critical role in ArtinM immunomodulatory activity.

    Directory of Open Access Journals (Sweden)

    Vania Sammartino Mariano

    Full Text Available TLR2 plays a critical role in the protection against Paracoccidioides brasiliensis conferred by ArtinM administration. ArtinM, a D-mannose-binding lectin from Artocarpus heterophyllus, induces IL-12 production in macrophages and dendritic cells, which accounts for the T helper1 immunity that results from ArtinM administration. We examined the direct interaction of ArtinM with TLR2using HEK293A cells transfected with TLR2, alone or in combination with TLR1 or TLR6, together with accessory proteins. Stimulation with ArtinM induced NF-κB activation and interleukin (IL-8 production in cells transfected with TLR2, TLR2/1, or TLR2/6. Murine macrophages that were stimulated with ArtinM had augmented TLR2 mRNA expression. Furthermore, pre-incubation of unstimulated macrophages with an anti-TLR2 antibody reduced the cell labeling with ArtinM. In addition, a microplate assay revealed that ArtinM bound to TLR2 molecules that had been captured by specific antibodies from a macrophages lysate. Notably,ArtinM binding to TLR2 was selectively inhibited when the lectin was pre-incubated with mannotriose. The biological relevance of the direct interaction of ArtinM with TLR2 glycans was assessed using macrophages from TLR2-KOmice, which produced significantly lower levels of IL-12 and IL-10 in response to ArtinM than macrophages from wild-type mice. Pre-treatment of murine macrophages with pharmacological inhibitors of signaling molecules demonstrated the involvement of p38 MAPK and JNK in the IL-12 production induced by ArtinM and the involvement ofPI3K in IL-10 production. Thus, ArtinM interacts directly with TLR2 or TLR2 heterodimers in a carbohydrate recognition-dependent manner and functions as a TLR2 agonist with immunomodulatory properties.

  9. Both TLR2 and TRIF contribute to interferon-β production during Listeria infection.

    Directory of Open Access Journals (Sweden)

    Camille Aubry

    Full Text Available Synthesis of interferon-β (IFN-β is an innate response to cytoplasmic infection with bacterial pathogens. Our recent studies showed that Listeria monocytogenes limits immune detection and IFN-β synthesis via deacetylation of its peptidoglycan, which renders the bacterium resistant to lysozyme degradation. Here, we examined signaling requirements for the massive IFN-β production resulting from the infection of murine macrophages with a mutant strain of L. monocytogenes, ΔpgdA, which is unable to modify its peptidoglycan. We report the identification of unconventional signaling pathways to the IFN-β gene, requiring TLR2 and bacterial internalization. Induction of IFN-β was independent of the Mal/TIRAP adaptor protein but required TRIF and the transcription factors IRF3 and IRF7. These pathways were stimulated to a lesser degree by wild-type L. monocytogenes. They operated in both resident and inflammatory macrophages derived from the peritoneal cavity, but not in bone marrow-derived macrophages. The novelty of our findings thus lies in the first description of TLR2 and TRIF as two critical components leading to the induction of the IFN-β gene and in uncovering that individual macrophage populations adopt different strategies to link pathogen recognition signals to IFN-β gene expression.

  10. Altered Expression of TLR2 and TLR4 on Peripheral CD14+ Blood Monocytes in Children with Urinary Tract Infection.

    Science.gov (United States)

    Karananou, Panagiota; Fleva, Alexandra; Tramma, Despoina; Alataki, Anastasia; Pavlitou-Tsiontsi, Aikaterini; Emporiadou-Peticopoulou, Maria; Papadopoulou-Alataki, Efimia

    2016-01-01

    Urinary tract infection (UTI) is the second most common bacterial infection, after otitis media, in infants and children. The mechanisms of disease susceptibility and the role of immunity in the pathogenesis of UTI in children have been evaluated. In recent years, Toll-Like Receptors (TLRs) have been recognized as specific components of the innate immune system constituting important mediators in host immune recognition. The aim of the present study was to determine ΤLR2 and TLR4 expression during the acute phase of UTI in infants and children by measuring the CD14/TLR2 and CD14/TLR4 expression on monocytes. We also attempted to compare the TLRs expression with the immunological status of the patients to healthy children. The study group consisted of 60 children (36 females and 24 males) and the control group included 60 age-matched pediatric subjects (27 females and 33 males). In our study, no antibody deficiency was found either in the children with UTI or in healthy subjects. There might be a connection between low IgA, IgG, and IgG subclasses serum levels and UTI as there was a statistically significant difference between patients and healthy children. A higher expression of CD14/TLR2 was revealed in patients (90,07%) compared to controls (85,48%) as well as CD14/TLR4 in patients (90,53%) compared to controls (87,25%) (statistically significant difference, p UTIs' pathogenesis in children.

  11. TLR4 deficiency promotes autophagy during cigarette smoke-induced pulmonary emphysema.

    Science.gov (United States)

    An, Chang Hyeok; Wang, Xiao Mei; Lam, Hilaire C; Ifedigbo, Emeka; Washko, George R; Ryter, Stefan W; Choi, Augustine M K

    2012-11-01

    Toll-like receptors (TLRs) exert important nonimmune functions in lung homeostasis. TLR4 deficiency promotes pulmonary emphysema. We examined the role of TLR4 in regulating cigarette smoke (CS)-induced autophagy, apoptosis, and emphysema. Lung tissue was obtained from chronic obstructive lung disease (COPD) patients. C3H/HeJ (Tlr4-mutated) mice and C57BL/10ScNJ (Tlr4-deficient) mice and their respective control strains were exposed to chronic CS or air. Human or mouse epithelial cells (wild-type, Tlr4-knockdown, and Tlr4-deficient) were exposed to CS-extract (CSE). Samples were analyzed for TLR4 expression, and for autophagic or apoptotic proteins by Western blot analysis or confocal imaging. Chronic obstructive lung disease lung tissues and human pulmonary epithelial cells exposed to CSE displayed increased TLR4 expression, and increased autophagic [microtubule-associated protein-1 light-chain-3B (LC3B)] and apoptotic (cleaved caspase-3) markers. Beas-2B cells transfected with TLR4 siRNA displayed increased expression of LC3B relative to control cells, basally and after exposure to CSE. The basal and CSE-inducible expression of LC3B and cleaved caspase-3 were elevated in pulmonary alveolar type II cells from Tlr4-deficient mice. Wild-type mice subjected to chronic CS-exposure displayed airspace enlargement;, however, the Tlr4-mutated or Tlr4-deficient mice exhibited a marked increase in airspace relative to wild-type mice after CS-exposure. The Tlr4-mutated or Tlr4-deficient mice showed higher levels of LC3B under basal conditions and after CS exposure. The expression of cleaved caspase-3 was markedly increased in Tlr4-deficient mice exposed to CS. We describe a protective regulatory function of TLR4 against emphysematous changes of the lung in response to CS.

  12. Efficacy of chimeric DNA vaccines encoding Eimeria tenella 5401 and chicken IFN-γ or IL-2 against coccidiosis in chickens.

    Science.gov (United States)

    Song, Xiaokai; Huang, Xinmei; Yan, Ruofeng; Xu, Lixin; Li, Xiangrui

    2015-09-01

    Chimeric DNA vaccines encoding Eimeria tenella (E. tenella) surface antigen 5401 were constructed and their efficacies against E. tenella challenge were studied. The open reading frame (ORF) of 5401 was cloned into the prokaryotic expression vector pGEX-4T2 to express the recombinant protein and the expressed recombinant protein was identified by Western blot. The ORF of 5401 and chicken cytokine gene IFN-γ or IL-2 were cloned into the eukaryotic expression vector pVAX1 consecutively to construct DNA vaccines pVAX-5401-IFN-γ, pVAX-5401-IL-2 and pVAX-5401. The expression of aim genes in vivo was detected by reverse transcription-polymerase chain reaction and Western blot. Fourteen-day-old chickens were inoculated twice at an interval of 7 days with 100 µg of plasmids pVAX-5401, pVAX-5401-IFN-γ and pVAX-5401-IL-2 or 200 µg of recombinant 5401 protein by leg intramuscular injection, respectively. Seven days after the second inoculation, all chickens except the unchallenged control group were challenged orally with 5 × 10(4) sporulated oocysts of E. tenella. Seven days after challenge, all chickens were weighted and slaughtered to determine the effects of immunization. The results showed the recombinant protein was about 90 kDa and reacted with antiserum against soluble sporozoites. The animal experiment showed that all the DNA vaccines pVAX-5401, pVAX-5401-IFN-γ or pVAX-5401-IL-2 and the recombinant 5401 protein could obviously alleviate body weight loss and cecal lesions as compared with non-vaccinated challenged control and empty vector pVAX1control. Furthermore, pVAX-5401-IFN-γ or pVAX-5401-IL-2 induced anti-coccidial index (ACI) of 180.01 or 177.24 which were significantly higher than that of pVAX-5401. The results suggested that 5401 was an effective candidate antigen for vaccine. This finding also suggested that chicken IFN-γ or IL-2 could effectively improve the efficacies of DNA vaccines against avian coccidiosis. Copyright © 2015 Elsevier

  13. TLR4, NOD1 and NOD2 mediate immune recognition of putative newly identified periodontal pathogens.

    Science.gov (United States)

    Marchesan, Julie; Jiao, Yizu; Schaff, Riley A; Hao, Jie; Morelli, Thiago; Kinney, Janet S; Gerow, Elizabeth; Sheridan, Rachel; Rodrigues, Vinicius; Paster, Bruce J; Inohara, Naohiro; Giannobile, William V

    2016-06-01

    Periodontitis is a polymicrobial inflammatory disease that results from the interaction between the oral microbiota and the host immunity. Although the innate immune response is important for disease initiation and progression, the innate immune receptors that recognize both classical and putative periodontal pathogens that elicit an immune response have not been elucidated. By using the Human Oral Microbe Identification Microarray (HOMIM), we identified multiple predominant oral bacterial species in human plaque biofilm that strongly associate with severe periodontitis. Ten of the identified species were evaluated in greater depth, six being classical pathogens and four putative novel pathogens. Using human peripheral blood monocytes (HPBM) and murine bone-marrow-derived macrophages (BMDM) from wild-type (WT) and Toll-like receptor (TLR)-specific and MyD88 knockouts (KOs), we demonstrated that heat-killed Campylobacter concisus, Campylobacter rectus, Selenomonas infelix, Porphyromonas endodontalis, Porphyromonas gingivalis, and Tannerella forsythia mediate high immunostimulatory activity. Campylobacter concisus, C. rectus, and S. infelix exhibited robust TLR4 stimulatory activity. Studies using mesothelial cells from WT and NOD1-specific KOs and NOD2-expressing human embryonic kidney cells demonstrated that Eubacterium saphenum, Eubacterium nodatum and Filifactor alocis exhibit robust NOD1 stimulatory activity, and that Porphyromonas endodontalis and Parvimonas micra have the highest NOD2 stimulatory activity. These studies allowed us to provide important evidence on newly identified putative pathogens in periodontal disease pathogenesis showing that these bacteria exhibit different immunostimulatory activity via TLR4, NOD1, and NOD2 (Clinicaltrials.gov NCT01154855). © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Antibodies against Marinobacter algicola and Salmonella typhimurium flagellins do not cross-neutralize TLR5 activation.

    Directory of Open Access Journals (Sweden)

    Raul Terron-Exposito

    Full Text Available Flagellins evoke strong innate and adaptive immune responses. These proteins may play a key role as radioprotectors, exert antitumoral activity in certain types of tumor and reduce graft-versus-host disease in allogeneic hematopoietic stem cell transplant recipients. Notwithstanding, flagellins are highly immunogenic, and repeated use leads to their neutralization by systemic antibodies. This neutralization is not prevented by using functional deleted flagellins. These observations led us to explore the possibility of preventing initial neutralization by means of another functional flagellin that does not belong to common pathogenic bacteria but that has the capacity to activate TLR5. Here we characterized the functional capacity of the two-phase Marinobacter algicola (MA-derived flagellins (F and FR as systemic and mucosal adjuvants and compared their performance with that of Salmonella typhimurium (STF flagellins (FljB and FliC. We also report for the first time on the in vitro and in vivo capacity of various flagellins to trigger TLR5 activation in the presence of species-specific anti-flagellin antibodies, the cross-neutralization mediated by these antibodies, and the sequential use of these flagellins for TLR5 activation. Our results showed that MA flagellins behave in a similar way to STF ones, inducing pro-inflammatory cytokines (IL8, CCL20, CCL2 and evoking a strong in vivo antibody response against a model epitope. More importantly, MA flagellins were fully functional, in vitro or in vivo, in the presence of a high concentration of neutralizing anti-flagellin STF antibodies, and STF flagellin was not inhibited by neutralizing anti-flagellin MA antibodies. The use of active flagellins from distinct bacteria could be a useful approach to prevent systemic neutralization of this group of adjuvants and to facilitate the rational design of flagellin-based vaccines and/or other therapeutic treatments (against ischemia, acute renal failure

  15. Genetic variation at Exon2 of TLR4 gene and its association with ...

    African Journals Online (AJOL)

    This study was conducted to analyze the polymorphisms of chicken Toll-like receptors 4(TLR4) gene and aimed to provide a theoretical foundation for a further research on correlation between chicken TLR4 gene and disease resistance. Genetic variations at exon 2 of TLR4 gene in 14 chicken breeds and the red jungle ...

  16. DMPD: Signal integration between IFNgamma and TLR signalling pathways in macrophages. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16920490 Signal integration between IFNgamma and TLR signalling pathways in macroph...tml) (.csml) Show Signal integration between IFNgamma and TLR signalling pathways in macrophages. PubmedID 16920490 Title Signal inte...gration between IFNgamma and TLR signalling pathways in

  17. Role of TLR4 gene polymorphisms in the colorectal cancer risk ...

    African Journals Online (AJOL)

    Saniya Nissar

    2016-05-26

    May 26, 2016 ... This is an open access article under the CC BY-NC-ND license ... eliminate infectious pathogens and cancer debris [5–7]. The TLR4 gene is .... evidence of involvement of TLR4 gene in driving CRC and this. TLR4 may serve ...

  18. An unusual dimeric structure and assembly for TLR4 regulator RP105-MD-1

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sung-il; Hong, Minsun; Wilson, Ian A [Scripps

    2011-11-16

    RP105-MD-1 modulates the TLR4-MD-2-mediated, innate immune response against bacterial lipopolysaccharide (LPS). The crystal structure of the bovine 1:1 RP105-MD-1 complex bound to a putative endogenous lipid at 2.9 Å resolution shares a similar overall architecture to its homolog TLR4-MD-2 but assembles into an unusual 2:2 homodimer that differs from any other known TLR-ligand assembly. The homodimer is assembled in a head-to-head orientation that juxtaposes the N-terminal leucine-rich repeats (LRRs) of the two RP105 chains, rather than the usual tail-to-tail configuration of C-terminal LRRs in ligand-activated TLR dimers, such as TLR1-TRL2, TLR2-TLR6, TLR3-TLR3 and TLR4-TLR4. Another unusual interaction is mediated by an RP105-specific asparagine-linked glycan, which wedges MD-1 into the co-receptor binding concavity on RP105. This unique mode of assembly represents a new paradigm for TLR complexes and suggests a molecular mechanism for regulating LPS responses.

  19. DMPD: New insights into the regulation of TLR signaling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16698941 New insights into the regulation of TLR signaling. Miggin SM, O'Neill LA. ...J Leukoc Biol. 2006 Aug;80(2):220-6. Epub 2006 May 12. (.png) (.svg) (.html) (.csml) Show New insights into ...the regulation of TLR signaling. PubmedID 16698941 Title New insights into the regulation of TLR signaling.

  20. Genetic Diversity of IFγ, IL1β, TLR2, and TLR8 Loci in Pulmonary Tuberculosis in Kazakhstan

    Directory of Open Access Journals (Sweden)

    Dauren Yerezhepov

    2014-12-01

    Full Text Available Introduction. Tuberculosis (TB is caused by bacterium Mycobacterium tuberculosis (MTB, and according to the WHO, up to 30% of world population is infected with latent TB. Pathogenesis of TB is multifactorial, and its development depends on environmental, social, microbial, and genetic factors of both the bacterium and the host. The number of TB cases in Kazakhstan has decreased in the past decade, but multidrug-resistant (MDR TB cases are dramatically increasing. Polymorphisms in genes responsible for immune response have been associated with TB susceptibility. The objective of this study was to investigate the risk of developing pulmonary TB (PTB associated with polymorphisms in several inflammatory pathway genes among Kazakhstani population.Methods. 703 participants from 3 regions of Kazakhstan were recruited for a case-control study. 251 participants had pulmonary TB (PTB, and 452 were healthy controls (HC. Males and females represented 42.39% and 57.61%, respectively. Of all participants, 67.4% were Kazakhs, 22.8% Russians, 3.4% Ukrainians, and 6.4% were of other origins. Clinical and epidemiological data were collected from medical records, interviews, and questionnaires. DNA samples were genotyped using TaqMan assay on 4 polymorphisms: IFNγ (rs2430561 and IL1β (rs16944, TLR2 (rs5743708 and TLR8 (rs3764880. Statistical data was analyzed using SPSS 19.Results. Genotyping by IFγ, IL1β, TLR2 showed no significant association with PTB susceptibility (p > 0.05. TLR8 genotype A/G was significantly higher in females (F/M – 41.5%/1.3% and G/G in males (M/F – 49%/20.7% (χ2=161.43, p < 0.001. A significantly increased risk of PTB development was observed for TLR A/G with an adjusted OR of 1.48 (95%, CI: 0.96 - 2.28, and a protective feature was revealed for TLR8 G/G genotype (OR: 0.81, 95%, CI: 0.56 - 1.16, p = 0.024. Additional grouping by gender revealed that TLR8 G/G contributes as protective genotype (OR: 1.83, 95%, CI: 1.18 - 2.83, p

  1. Toll-like receptor-4 (TLR-4) expression on polymorphonuclear ...

    African Journals Online (AJOL)

    To establish a foundation for further researches on the improvement of polymorphonuclear neutrophil leukocytes (PMN) functions in dairy cow during perinatal period, the counting of PMN, as well as the mRNA and protein expression of toll-like receptor-4 (TLR-4) on PMN was studied during this critical period.

  2. DMPD: TLR signaling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available kira S. Publication Cell Death Differ. 2006 May;13(5):816-25. Pathway - PNG File (.png) SVG File (.svg) HTML File (.html...16410796 TLR signaling. Kawai T, Akira S. Cell Death Differ. 2006 May;13(5):816-25. (.png) (.svg) (.html

  3. [Changes of FoxP3, CD4(+)CD25(+) regulatory T cells, TLR2 and TLR9 in children with infectious mononucleosis].

    Science.gov (United States)

    Wang, Qiang; Wang, Zuo-Feng; Cao, Mei; Wang, Zhi-Ying

    2013-04-01

    The aim of this study was to investigate the effects of TLR2, TLR9, CD4(+)CD25(+) regulatory T cells (Treg) and transcription factor FoxP3 in the pathogenesis of children with infectious mononucleosis (IM). Thirty-five acute IM patients admitted in our hospital from April 2010 to January 2011 were enrolled in this study. Thirty-five healthy subjects were taken as control. The thirty-five patients before treatment were considered as patients in acute stage, after treatment and without clinical symptom they were thought as patients in recovery stage. The expression levels of TLR2, TLR9 and FoxP3 mRNA were detected by real time PCR using SYBR Green I. The expression of T lymphocyte subset CD4(+)CD25(+) in peripheral blood mononuclear cells was detected by flow cytometry. The results showed that the relative levels of TLR2 mRNA (4.03 ± 0.56), TLR9 mRNA (8.88 ± 1.56) in peripheral blood mononuclear cells of IM patients in acute stage were significantly higher than those of the controls [TLR2 mRNA (2.22 ± 0.57), TLR9 mRNA (3.63 ± 1.30)] and IM patients in recovery stage [TLR2 mRNA (2.76 ± 0.83), TLR9 mRNA (5.34 ± 1.60)] (P 0.05). It is concluded that the expression of CD4(+)CD25(+)regulatory T cells is reduced, and its special transcription factor FoxP3 mRNA is down-regulated, but expression levels of TLR2 mRNA, TLR9 mRNA are up-regulated in IM patients of acute stage.

  4. TLR4 has a TP53-dependent dual role in regulating breast cancer cell growth

    OpenAIRE

    Haricharan, Svasti; Brown, Powel

    2015-01-01

    This study fundamentally alters our understanding of how TLR4 drives breast cancer. Although TLR4 was previously considered a tumor promoter, we demonstrate a complex, TP53-dependent role for TLR4 in regulating tumor growth. TP53 is a tumor suppressor commonly inactivated across cancer types. In TP53 wild-type cancer cells, TLR4 activation causes secretion of IFN-γ into the microenvironment, resulting in induction of p21 and inhibition of cell growth. Conversely, TLR4 activation in TP53 mutan...

  5. The Processed Amino-Terminal Fragment of Human TLR7 Acts as a Chaperone To Direct Human TLR7 into Endosomes

    Science.gov (United States)

    Shepherd, Dawn; Booth, Sarah; Waithe, Dominic; Reis e Sousa, Caetano

    2015-01-01

    TLR7 mediates innate immune responses to viral RNA in endocytic compartments. Mouse and human (h)TLR7 undergo proteolytic cleavage, resulting in the generation of a C-terminal fragment that accumulates in endosomes and associates with the signaling adaptor MyD88 upon receptor triggering by TLR7 agonists. Although mouse TLR7 is cleaved in endosomes by acidic proteases, hTLR7 processing can occur at neutral pH throughout the secretory pathway through the activity of furin-like proprotein convertases. However, the mechanisms by which cleaved hTLR7 reaches the endosomal compartment remain unclear. In this study, we demonstrate that, after hTLR7 proteolytic processing, the liberated amino (N)-terminal fragment remains bound to the C terminus through disulfide bonds and provides key trafficking information that ensures correct delivery of the complex to endosomal compartments. In the absence of the N-terminal fragment, the C-terminal fragment is redirected to the cell surface, where it is functionally inactive. Our data reveal a novel role for the N terminus of hTLR7 as a molecular chaperone that provides processed hTLR7 with the correct targeting instructions to reach the endosomal compartment, hence ensuring its biological activity and preventing inadvertent cell surface responses to self-RNA. PMID:25917086

  6. Single-nucleotide polymorphisms in Toll-like receptor (TLR)-2, TLR4 and heat shock protein 70 genes and susceptibility to scrub typhus.

    Science.gov (United States)

    Janardhanan, Jeshina; Joseph Martin, Sherry; Astrup, Elisabeth; Veeramanikandan, R; Aukrust, Pål; Abraham, Ooriapadickal C; Varghese, George M

    2013-11-01

    Scrub typhus is a highly prevalent bacterial infection in India and South Asia that is caused by Orientia tsutsugamushi. The innate immune response to infections is modulated by Toll-like receptors (TLRs) and heat shock proteins (HSPs). This study was done to assess the prevalence and possible association of TLR and HSP polymorphisms in scrub typhus. TLR4 Asp299Gly, TLR4 Thr399Ile, TLR2 Arg753Gln and HSP70-2 A1267G are single-nucleotide polymorphisms (SNPs) that may modulate their activities, and these SNPs were assessed in 137 scrub typhus patients and 134 controls by PCR restriction fragment length polymorphism. We found that the two TLR4 mutations, TLR4 D299G and TLR4T399I, were present in 19.5% and 22% of the study population, respectively, and was in significant linkage disequilibrium with a D' of 0.8. The TLR2 mutation was found to be rare, whereas the HSP A>G mutation was very common (77.5%). Compared with the controls, the prevalence of heterozygous genotype of the TLR4D299G SNP, but not any of the other SNPs, was significantly higher among scrub typhus patients. Further studies using a larger sample size and more candidate genes may better enable in determining the role of these associations in susceptibility and severity of scrub typhus.

  7. The Probiotic Lactobacillus Prevents Citrobacter rodentium-Induced Murine Colitis in a TLR2-Dependent Manner.

    Science.gov (United States)

    Ryu, Seung-Hyun; Park, Jong-Hyung; Choi, Soo-Young; Jeon, Hee-Yeon; Park, Jin-Il; Kim, Jun-Young; Ham, Seung-Hoon; Choi, Yang-Kyu

    2016-07-28

    The main objective of this study was to investigate whether Lactobacillus rhamnosus GG (LGG) ameliorated the effects of Citrobactor rodentium infection in Toll-like receptor 2 (TLR2) knockout (KO) and TLR4 KO mice, as well as in wild-type C57BL/6 (B6) mice. TLR2 KO, TLR4 KO, and B6 mice were divided into three groups per each strain. Each group had an uninfected control group (n = 5), C. rodentium-infected group (n = 8), and LGG-pretreated C. rodentium-infected group (n = 8). The survival rate of B6 mice infected with C. rodentium was higher when pretreated with LGG. Pretreatment with LGG ameliorated C. rodentium-induced mucosal hyperplasia in B6 and TLR4 KO mice. However, in C-rodentium-infected TLR2 KO mice, mucosal hyperplasia persisted, regardless of pretreatment with LGG. In addition, LGG-pretreated B6 and TLR4 KO mice showed a decrease in spleen weight and downregulation of tumor necrosis factor alpha, interferon gamma, and monocyte chemotactic protein 1 mRNA expression compared with the non-pretreated group. In contrast, such changes were not observed in TLR2 KO mice, regardless of pretreatment with LGG. From the above results, we conclude that pretreatment with LGG ameliorates C. rodentium-induced colitis in B6 and TLR4 KO mice, but not in TLR2 KO mice. Therefore, LGG protects mice from C. rodentium-induced colitis in a TLR2-dependent manner.

  8. MiR-23a-5p modulates mycobacterial survival and autophagy during mycobacterium tuberculosis infection through TLR2/MyD88/NF-κB pathway by targeting TLR2.

    Science.gov (United States)

    Gu, Xing; Gao, Yan; Mu, De-Guang; Fu, En-Qing

    2017-05-15

    Autophagy plays a pivotal role in activating the antimicrobial host defense against Mycobacterium tuberculosis (M.tb.). The emerging roles of microRNAs (miRNAs) in regulating immune responses have attracted increasing attention in recent years. Appreciating the potential of host-directed therapies designed to control autophagy during mycobacterial infection, we focused on the influence of miR-23a-5p on the activation of macrophage autophagy during M.tb. infection in bone marrow-derived macrophages (BMDMs) and murine RAW264.7 cells. Here, we demonstrated that M.tb.-infection of macrophages lead to markedly enhanced expression of miR-23a-5p in a time- and dose-dependent manner. Furthermore, forced expression of miR-23a-5p accelerated the survival rate of intracellular mycobacteria, while transfection with miR-23a-5p inhibitors attenuated mycobacterial survival. More importantly, overexpression of miR-23a-5p dramatically prevented M.tb.-induced activation of autophagy in macrophages, whereas inhibitors of miR-23a-5p remarkably accelerated M.tb.-induced autophagy. Mechanistically, miR-23a-5p is able to modulate TLR2/MyD88/NF-κB signaling activity by targeting TLR2 in RAW264.7 cells in response to M.tb.-infection. Collectively, these findings demonstrated that miR-23a-5p modulated the innate host defense by promoting mycobacteria survival and inhibiting the activation of autophagy against M.tb. through TLR2/MyD88/NF-κB pathway by targeting TLR2, which may provide a promising therapeutic target for tuberculosis. Copyright © 2017 Elsevier Inc. All rights reserved.

  9. Extracellular histones promote thrombin generation through platelet-dependent mechanisms: involvement of platelet TLR2 and TLR4

    Science.gov (United States)

    Semeraro, Fabrizio; Ammollo, Concetta T.; Morrissey, James H.; Dale, George L.; Friese, Paul; Esmon, Naomi L.

    2011-01-01

    The release of histones from dying cells is associated with microvascular thrombosis and, because histones activate platelets, this could represent a possible pathogenic mechanism. In the present study, we assessed the influence of histones on the procoagulant potential of human platelets in platelet-rich plasma (PRP) and in purified systems. Histones dose-dependently enhanced thrombin generation in PRP in the absence of any trigger, as evaluated by calibrated automated thrombinography regardless of whether the contact phase was inhibited. Activation of coagulation required the presence of fully activatable platelets and was not ascribable to platelet tissue factor, whereas targeting polyphosphate with phosphatase reduced thrombin generation even when factor XII (FXII) was blocked or absent. In the presence of histones, purified polyphosphate was able to induce thrombin generation in plasma independently of FXII. In purified systems, histones induced platelet aggregation; P-selectin, phosphatidylserine, and FV/Va expression; and prothrombinase activity. Blocking platelet TLR2 and TLR4 with mAbs reduced the percentage of activated platelets and lowered the amount of thrombin generated in PRP. These data show that histone-activated platelets possess a procoagulant phenotype that drives plasma thrombin generation and suggest that TLR2 and TLR4 mediate the activation process. PMID:21673343

  10. Hyperin protects against LPS-induced acute kidney injury by inhibiting TLR4 and NLRP3 signaling pathways

    Science.gov (United States)

    Chunzhi, Gong; Zunfeng, Li; Chengwei, Qin; Xiangmei, Bu; Jingui, Yu

    2016-01-01

    Hyperin is a flavonoid compound derived from Ericaceae, Guttifera, and Celastraceae that has been shown to have various biological effects, such as anti-inflammatory and anti-oxidant effects. However, there is no evidence to show the protective effects of hyperin on lipopolysaccharide (LPS)-induced acute kidney injury (AKI). Therefore, we investigated the protective effects and mechanism of hyperin on LPS-induced AKI in mice. The levels of TNF-α, IL-6, and IL-1β were tested by ELISA. The effects of hyperin on blood urea nitrogen (BUN) and serum creatinine were also detected. In addition, the expression of TLR4, NF-κB, and NLRP3 were detected by western blot analysis. The results showed that hyperin significantly inhibited LPS-induced TNF-α, IL-6, and IL-1β production. The levels of BUN and creatinine were also suppressed by hyperin. Furthermore, LPS-induced TLR4 expression and NF-κB activation were also inhibited by hyperin. In addition, treatment of hyperin dose-dependently inhibited LPS-induced NLRP3 signaling pathway. In conclusion, the results showed that hyperin inhibited LPS-induced inflammatory response by inhibiting TLR4 and NLRP3 signaling pathways. Hyperin has potential application prospects in the treatment of sepsis-induced AKI. PMID:27813491

  11. A Novel Class of Small Molecule Agonists with Preference for Human over Mouse TLR4 Activation.

    Directory of Open Access Journals (Sweden)

    Jason D Marshall

    Full Text Available The best-characterized Toll-like receptor 4 (TLR4 ligands are lipopolysaccharide (LPS and its chemically modified and detoxified variant, monophosphoryl lipid A (MPL. Although both molecules are active for human TLR4, they demonstrate a potency preference for mouse TLR4 based on data from transfected cell lines and primary cells of both species. After a high throughput screening process of small molecule libraries, we have discovered a new class of TLR4 agonist with a species preference profile differing from MPL. Products of the 4-component Ugi synthesis reaction were demonstrated to potently trigger human TLR4-transfected HEK cells but not mouse TLR4, although inclusion of the human MD2 with mTLR4 was able to partially recover activity. Co-expression of CD14 was not required for optimal activity of Ugi compounds on transfected cells, as it is for LPS. The species preference profile for the panel of Ugi compounds was found to be strongly active for human and cynomolgus monkey primary cells, with reduced but still substantial activity for most Ugi compounds on guinea pig cells. Mouse, rat, rabbit, ferret, and cotton rat cells displayed little or no activity when exposed to Ugi compounds. However, engineering the human versions of TLR4 and MD2 to be expressed in mTLR4/MD2 deficient mice allowed for robust activity by Ugi compounds both in vitro and in vivo. These findings extend the range of compounds available for development as agonists of TLR4 and identify novel molecules which reverse the TLR4 triggering preference of MPL for mouse TLR4 over human TLR4. Such compounds may be amenable to formulation as more potent human-specific TLR4L-based adjuvants than typical MPL-based adjuvants.

  12. Toll-Like Receptor 4 in Bone Marrow-Derived Cells Contributes to the Progression of Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Hui Wang

    2014-01-01

    Full Text Available Diabetic retinopathy (DR is a major microvascular complication in diabetics, and its mechanism is not fully understood. Toll-like receptor 4 (TLR4 plays a pivotal role in the maintenance of the inflammatory state during DR, and the deletion of TLR4 eventually alleviates the diabetic inflammatory state. To further elucidate the mechanism of DR, we used bone marrow transplantation to establish reciprocal chimeric animals of TLR4 mutant mice and TLR4 WT mice combined with diabetes mellitus (DM induction by streptozotocin (STZ treatment to identify the role of TLR4 in different cell types in the development of the proinflammatory state during DR. TLR4 mutation did not block the occurrence of high blood glucose after STZ injection compared with WT mice but did alleviate the progression of DR and alter the expression of the small vessel proliferation-related genes, vascular endothelial growth factor (VEGF, and hypoxia inducible factor-1α (HIF-1α. Grafting bone marrow-derived cells from TLR4 WT mice into TLR4 mutant mice increased the levels of TNF-α, IL-1β, and MIP-2 and increased the damage to the retina. Similarly, VEGF and HIF-1α expression were restored by the bone marrow transplantation. These findings identify an essential role for TLR4 in bone marrow-derived cells contributing to the progression of DR.

  13. HMGB1 mediates endogenous TLR2 activation and brain tumor regression.

    Directory of Open Access Journals (Sweden)

    James F Curtin

    2009-01-01

    Full Text Available Glioblastoma multiforme (GBM is the most aggressive primary brain tumor that carries a 5-y survival rate of 5%. Attempts at eliciting a clinically relevant anti-GBM immune response in brain tumor patients have met with limited success, which is due to brain immune privilege, tumor immune evasion, and a paucity of dendritic cells (DCs within the central nervous system. Herein we uncovered a novel pathway for the activation of an effective anti-GBM immune response mediated by high-mobility-group box 1 (HMGB1, an alarmin protein released from dying tumor cells, which acts as an endogenous ligand for Toll-like receptor 2 (TLR2 signaling on bone marrow-derived GBM-infiltrating DCs.Using a combined immunotherapy/conditional cytotoxic approach that utilizes adenoviral vectors (Ad expressing Fms-like tyrosine kinase 3 ligand (Flt3L and thymidine kinase (TK delivered into the tumor mass, we demonstrated that CD4(+ and CD8(+ T cells were required for tumor regression and immunological memory. Increased numbers of bone marrow-derived, tumor-infiltrating myeloid DCs (mDCs were observed in response to the therapy. Infiltration of mDCs into the GBM, clonal expansion of antitumor T cells, and induction of an effective anti-GBM immune response were TLR2 dependent. We then proceeded to identify the endogenous ligand responsible for TLR2 signaling on tumor-infiltrating mDCs. We demonstrated that HMGB1 was released from dying tumor cells, in response to Ad-TK (+ gancyclovir [GCV] treatment. Increased levels of HMGB1 were also detected in the serum of tumor-bearing Ad-Flt3L/Ad-TK (+GCV-treated mice. Specific activation of TLR2 signaling was induced by supernatants from Ad-TK (+GCV-treated GBM cells; this activation was blocked by glycyrrhizin (a specific HMGB1 inhibitor or with antibodies to HMGB1. HMGB1 was also released from melanoma, small cell lung carcinoma, and glioma cells treated with radiation or temozolomide. Administration of either glycyrrhizin or anti

  14. TLR-dependent control of Francisella tularensis infection and host inflammatory responses.

    Directory of Open Access Journals (Sweden)

    Allison L Abplanalp

    2009-11-01

    Full Text Available Francisella tularensis is the causative agent of tularemia and is classified as a Category A select agent. Recent studies have implicated TLR2 as a critical element in the host protective response to F. tularensis infection, but questions remain about whether TLR2 signaling dominates the response in all circumstances and with all species of Francisella and whether F. tularensis PAMPs are predominantly recognized by TLR2/TLR1 or TLR2/TLR6. To address these questions, we have explored the role of Toll-like receptors (TLRs in the host response to infections with F. tularensis Live Vaccine Strain (LVS and F. tularensis subspecies (subsp. novicida in vivo.C57BL/6 (B6 control mice and TLR- or MyD88-deficient mice were infected intranasally (i.n. or intradermally (i.d. with F. tularensis LVS or with F. tularensis subsp. novicida. B6 mice survived >21 days following infection with LVS by both routes and survival of TLR1(-/-, TLR4(-/-, and TLR6(-/- mice infected i.n. with LVS was equivalent to controls. Survival of TLR2(-/- and MyD88(-/- mice, however, was significantly reduced compared to B6 mice, regardless of the route of infection or the subspecies of F. tularensis. TLR2(-/- and MyD88(-/- mice also showed increased bacterial burdens in lungs, liver, and spleen compared to controls following i.n. infection. Primary macrophages from MyD88(-/- and TLR2(-/- mice were significantly impaired in the ability to secrete TNF and other pro-inflammatory cytokines upon ex vivo infection with LVS. TNF expression was also impaired in vivo as demonstrated by analysis of bronchoalveolar lavage fluid and by in situ immunofluorescent staining.We conclude from these studies that TLR2 and MyD88, but not TLR4, play critical roles in the innate immune response to F. tularensis infection regardless of the route of infection or the subspecies. Moreover, signaling through TLR2 does not depend exclusively on TLR1 or TLR6 during F. tularensis LVS infection.

  15. Anticoccidial effects of coumestans from Eclipta alba for sustainable control of Eimeria tenella parasitosis in poultry production.

    Science.gov (United States)

    Michels, M G; Bertolini, L C T; Esteves, A F; Moreira, P; Franca, S C

    2011-04-19

    The aim of this study was to evaluate the anticoccidial efficacy of a product containing coumestans from Eclipta alba. Experimental conditions were set up as to reproduce the environment conditions for husbandry adopted in commercial broiler farms. Broilers were raised in broiler chicken shed provided with feeders, drinkers, illumination and temperature control systems and floor covering to afford an adequate nourishing environment. Male Cobb broilers (240) were assigned to four experimental groups being each experimental group set apart in rice straw-covered shed isolated with wire mesh. One-day-old broilers were reared in a coccidian-free environment with ad libitum supply of filtered water and freely available standard feed, from the 1st to the 35th day of life. The T1 group received standard feed (negative control); T2 was treated with standard feed supplemented with 66 ppm of salinomycin (positive control); groups T3 and T4 had standard feed supplemented with the ethyl acetate fraction from methanolic extract of E. alba aerial parts, which contains the coumestans WL and DWL (120 and 180 ppm, respectively). The chicken broilers were individually infected with 2 × 104 oocysts of Eimeria tenella when they were 14 days old and were monitored weekly to evaluate zootechnical parameters such as weight gain and food conversion ratio. Counting of coccidial oocyst in chicken feces was assessed from random samples, from the 21st to 28th days of life, which corresponded to 7-14 days after the infection. Five chickens selected at random from each experimental group were subsequently euthanized at 21, 28 or 35 days of life to determine the lesion score in the cecal region and to excise a cecum portion for histopathological evaluation. The group treated with coumestans from E. alba presented an average weight gain and food conversion ratio higher than the negative control group and similar to the mean value of the positive control group. Coumestan-treated groups showed a

  16. TLR9 expression in glioma tissues correlated to glioma progression and the prognosis of GBM patients

    International Nuclear Information System (INIS)

    Wang, Chao; Cao, Shouqiang; Yan, Ying; Ying, Qiao; Jiang, Tao; Xu, Ke; Wu, Anhua

    2010-01-01

    Our study aims to evaluate the expression of TLR9 in glioma tissues, examine the association between TLR9 expression, clinicopathological variables, and glioma patient outcome, we further characterized the direct effects of TLR9 agonist CpG ODN upon the proliferation and invasion of glioma cells in vitro. RT-PCR and immunofluorescence were used to determine the expression of TLR9 in glioma cell lines and clinical glioma samples. Tissue microarry and immunohistochemistry were applied to evaluated TLR9 expression in 292 newly diagnosed glioma and 13 non-neoplastic brain tissues. We further investigated the effect of CpG ODN on the proliferation and invasion of glioma cells in vitro with MTT assays and matrigel transwell assay respectively. RT-PCR showed that TLR9 expressed in all the glioma samples and glioma cell lines we examined. The tissue array analysis indicated that TLR9 expression is correlated with malignancy of glioma (p < 0.01). Multivariate Cox regression analysis revealed that TLR9 expression is an independent prognostic factor for PFS of GBM patients(P = 0.026). TLR9 agonist CpG ODN has no significant effect on glioma proliferation, but matrigel transwell analysis showed that TLR9 agonist CpG ODN can significantly enhance glioma invasion in vitro. Our data indicated that TLR9 expression increases according to the histopathological grade of glioma, and the TLR9 expression level is related to the PFS of GBM patients. In addition, our findings warrant caution in the directly injection of TLR9 agonist CpG ODN into glioma tissues for the glioma immunotherapy

  17. Small Interference RNA Targeting TLR4 Gene Effectively Attenuates Pulmonary Inflammation in a Rat Model

    Directory of Open Access Journals (Sweden)

    Feixiang Wu

    2012-01-01

    Full Text Available Objective. The present study was to investigate the feasibility of adenovirus-mediated small interference RNA (siRNA targeting Toll-like receptor 4 (TLR4 gene in ameliorating lipopolysaccharide- (LPS- induced acute lung injury (ALI. Methods. In vitro, alveolar macrophages (AMs were treated with Ad-siTLR4 and Ad-EFGP, respectively, for 12 h, 24 h, and 48 h, and then with LPS (100 ng/mL for 2 h, and the function and expression of TLR4 were evaluated. In vivo, rats received intratracheal injection of 300 μL of normal saline (control group, 300 μL of Ad-EGFP (Ad-EGFP group, or 300 μL of Ad-siTLR4 (Ad-siTLR4 group and then were intravenously treated with LPS (50 mg/kg to induce ALI. Results. Ad-siTLR4 treatment significantly reduced TLR4 expression and production of proinflammatory cytokines following LPS treatment both in vitro and in vivo. Significant alleviation of tissue edema, microvascular protein leakage, and neutrophil infiltration was observed in the AdsiTLR4-treated animals. Conclusion. TLR4 plays a critical role in LPS-induced ALI, and transfection of Ad-siTLR4 can effectively downregulate TLR4 expression in vitro and in vivo, accompanied by alleviation of LPS-induced lung injury. These findings suggest that TLR4 may serve as a potential target in the treatment of ALI and RNA interfering targeting TLR4 expression represents a therapeutic strategy.

  18. Customized laboratory TLR4 and TLR2 detection method from peripheral human blood for early detection of doxorubicin-induced cardiotoxicity.

    Science.gov (United States)

    Pop-Moldovan, A L; Trofenciuc, N-M; Dărăbanţiu, D A; Precup, C; Branea, H; Christodorescu, R; Puşchiţă, M

    2017-05-01

    Cancer treatments can have significant cardiovascular adverse effects that can cause cardiomyopathy and heart failure with reduced survival benefit and considerable decrease in the use of antineoplastic therapy. The purpose of this study is to assess the role of TLR2 and TLR4 gene expression as an early marker for the risk of doxorubicin-induced cardiomyopathy in correlation with early diastolic dysfunction in patients treated with doxorubicin. Our study included 25 consecutive patients who received treatment with doxorubicin for hematological malignancies (leukemia, lymphomas or multiple myeloma), aged 18-65 years, with a survival probability>6 months and with left ventricular ejection fraction>50%. Exclusion criteria consisted of the following: previous anthracycline therapy, previous radiotherapy, history of heart failure or chronic renal failure, atrial fibrillation, and pregnancy. In all patients, in fasting state, a blood sample was drawn for the assessment of TLR2 and TLR4 gene expression. Gene expression was assessed by quantitative reverse transcription PCR (qRT-PCR) using blood collection, RNA isolation, cDNA reverse transcription, qRT-PCR and quantification of the relative expression. At enrollment, all patients were evaluated clinically; an ECG and an echocardiography were performed. The average amount of gene expression units was 0.113 for TLR4 (range 0.059-0.753) and 0.218 for TLR2 (range 0.046-0.269). The mean mRNA extracted quantity was 113 571 ng/μl. As for the diastolic function parameters, criteria for diastolic dysfunction were present after 6 months in 16 patients (64%). In these patients, the mean values for TLR4 were 0.1198625 and for TLR2 were 0.16454 gene expression units. As for the diastolic function parameters, criteria for diastolic dysfunction were present after 6 months in 16 patients (64%). In these patients, the mean value for TLR2 was 0.30±0.19 and for TLR4 was 0.15±0.04. The corresponding values for the patients who did not

  19. TLR7/TLR8 Activation Restores Defective Cytokine Secretion by Myeloid Dendritic Cells but Not by Plasmacytoid Dendritic Cells in HIV-Infected Pregnant Women and Newborns.

    Directory of Open Access Journals (Sweden)

    Elaine Cristina Cardoso

    Full Text Available Mother-to-child transmission (MTCT of HIV-1 has been significantly reduced with the use of antiretroviral therapies, resulting in an increased number of HIV-exposed uninfected infants. The consequences of HIV infection on the innate immune system of both mother-newborn are not well understood. In this study, we analyzed peripheral blood and umbilical cord blood (CB collected from HIV-1-infected and uninfected pregnant women. We measured TNF-α, IL-10 and IFN-α secretion after the stimulation of the cells with agonists of both extracellular Toll-like receptors (TLRs (TLR2, TLR4 and TLR5 and intracellular TLRs (TLR7, TLR7/8 and TLR9. Moreover, as an indicator of the innate immune response, we evaluated the responsiveness of myeloid dendritic cells (mDCs and plasmacytoid DCs (pDCs to TLRs that are associated with the antiviral response. Our results showed that peripheral blood mononuclear cells (PBMCs from HIV-1-infected mothers and CB were defective in TNF-α production after activation by TLR2, TLR5, TLR3 and TLR7. However, the TNF-α response was preserved after TLR7/8 (CL097 stimulation, mainly in the neonatal cells. Furthermore, only CL097 activation was able to induce IL-10 and IFN-α secretion in both maternal and CB cells in the infected group. An increase in IFN-α secretion was observed in CL097-treated CB from HIV-infected mothers compared with control mothers. The effectiveness of CL097 stimulation was confirmed by observation of similar mRNA levels of interferon regulatory factor-7 (IRF-7, IFN-α and TNF-α in PBMCs of both groups. The function of both mDCs and pDCs was markedly compromised in the HIV-infected group, and although TLR7/TLR8 activation overcame the impairment in TNF-α secretion by mDCs, such stimulation was unable to reverse the dysfunctional type I IFN response by pDCs in the HIV-infected samples. Our findings highlight the dysfunction of innate immunity in HIV-infected mother-newborn pairs. The activation of the TLR7

  20. TLR7/TLR8 Activation Restores Defective Cytokine Secretion by Myeloid Dendritic Cells but Not by Plasmacytoid Dendritic Cells in HIV-Infected Pregnant Women and Newborns.

    Science.gov (United States)

    Cardoso, Elaine Cristina; Pereira, Nátalli Zanete; Mitsunari, Gabrielle Eimi; Oliveira, Luanda Mara da Silva; Ruocco, Rosa Maria S A; Francisco, Rossana Pulcineli Vieira; Zugaib, Marcelo; da Silva Duarte, Alberto José; Sato, Maria Notomi

    2013-01-01

    Mother-to-child transmission (MTCT) of HIV-1 has been significantly reduced with the use of antiretroviral therapies, resulting in an increased number of HIV-exposed uninfected infants. The consequences of HIV infection on the innate immune system of both mother-newborn are not well understood. In this study, we analyzed peripheral blood and umbilical cord blood (CB) collected from HIV-1-infected and uninfected pregnant women. We measured TNF-α, IL-10 and IFN-α secretion after the stimulation of the cells with agonists of both extracellular Toll-like receptors (TLRs) (TLR2, TLR4 and TLR5) and intracellular TLRs (TLR7, TLR7/8 and TLR9). Moreover, as an indicator of the innate immune response, we evaluated the responsiveness of myeloid dendritic cells (mDCs) and plasmacytoid DCs (pDCs) to TLRs that are associated with the antiviral response. Our results showed that peripheral blood mononuclear cells (PBMCs) from HIV-1-infected mothers and CB were defective in TNF-α production after activation by TLR2, TLR5, TLR3 and TLR7. However, the TNF-α response was preserved after TLR7/8 (CL097) stimulation, mainly in the neonatal cells. Furthermore, only CL097 activation was able to induce IL-10 and IFN-α secretion in both maternal and CB cells in the infected group. An increase in IFN-α secretion was observed in CL097-treated CB from HIV-infected mothers compared with control mothers. The effectiveness of CL097 stimulation was confirmed by observation of similar mRNA levels of interferon regulatory factor-7 (IRF-7), IFN-α and TNF-α in PBMCs of both groups. The function of both mDCs and pDCs was markedly compromised in the HIV-infected group, and although TLR7/TLR8 activation overcame the impairment in TNF-α secretion by mDCs, such stimulation was unable to reverse the dysfunctional type I IFN response by pDCs in the HIV-infected samples. Our findings highlight the dysfunction of innate immunity in HIV-infected mother-newborn pairs. The activation of the TLR7/8 pathway

  1. Modulation of IL-33/ST2-TIR and TLR signalling pathway by fingolimod and analogues in immune cells.

    Science.gov (United States)

    Rüger, K; Ottenlinger, F; Schröder, M; Zivković, A; Stark, H; Pfeilschifter, J M; Radeke, H H

    2014-12-01

    For the immune modulatory drug fingolimod (FTY720), lymphocyte sequestration has been extensively studied and accepted as mode of action. Further, direct effects on immune cell signalling are incompletely understood. Herein, we used the parent drug and newly synthesized analogues to investigate their effects on dendritic cell (DC) calcium signalling and on Th1, Th2 and Th17 responses. DC calcium signalling was determined with a single cell-based confocal assay and IL-33/ST2-TIR Th2-like response with ST2-transduced EL4-6.1 thymoma cells. The Th1/Th17 responses were examined with a LPS/TLR-enhanced antigen presentation assay with OVA-TCRtg CD4 and CD8 spleen cells. Our results revealed a comparable influence of fingolimod and S1P on intracellular calcium level in DC, while an oxy-derivative of fingolimod exhibited an EC50 of 3.3 nm, being 14 times more potent than FTY720-P. The IL-33/ST2-TIR Th2-like response in ST2-EL4 cells was inhibited by fingolimod and analogues at varying degrees. Using the OVA-TCRtg LPS/TLR-enhanced spleen cell assay, we found that fingolimod inhibited both IL-17 and IFN-γ production. In contrast, fingolimod phosphate failed to decrease Th1 cytokines. Interestingly, the effects of the parent compound fingolimod were modulated by the PP2A inhibitor okadaic acid, thus suggesting PP2A as relevant intracellular target. These studies describe detailed immune-modulating properties of fingolimod, including interference with a prototypical Th2 response via IL-33/ST2-TIR. Moreover, differential effects of fingolimod versus its phosphorylated derivative on TLR-activated and antigen-dependent Th1 activation suggest PP2A as an additional target of fingolimod immune therapy. Together with the analogues tested, these data may guide the development of more specific fingolimod derivatives. © 2014 John Wiley & Sons Ltd.

  2. T cells exacerbate Lyme borreliosis in TLR2-deficient mice

    Directory of Open Access Journals (Sweden)

    Carrie E. Lasky

    2016-11-01

    Full Text Available Infection of humans with the spirochete, Borrelia burgdorferi, causes Lyme borreliosis and can lead to clinical manifestations such as, arthritis, carditis and neurological conditions. Experimental infection of mice recapitulates many of these symptoms and serves as a model system for the investigation of disease pathogenesis and immunity. Innate immunity is known to drive the development of Lyme arthritis and carditis, but the mechanisms driving this response remain unclear. Innate immune cells recognize B. burgdorferi surface lipoproteins primarily via Toll-like receptor (TLR2; however, previous work has demonstrated TLR2-/- mice had exacerbated disease and increased bacterial burden. We demonstrate increased CD4 and CD8 T cell infiltrates in B. burgdorferi-infected joints and hearts of C3H TLR2-/- mice. In vivo depletion of either CD4 or CD8 T cells reduced Borrelia-induced joint swelling and lowered tissue spirochete burden, while depletion of CD8 T cells alone reduced disease severity scores. Exacerbation of Lyme arthritis correlated with increased production of CXCL9 by synoviocytes and this was reduced with CD8 T cell depletion. These results demonstrate T cells can exacerbate Lyme disease pathogenesis and prolong disease resolution possibly through dysregulation of inflammatory responses and inhibition of bacterial clearance.

  3. Effects of TLR agonists and viral infection on cytokine and TLR expression in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Arnemo, Marianne; Kavaliauskis, Arturas; Gjøen, Tor

    2014-10-01

    The development of efficient and cheap vaccines against several aquatic viruses is necessary for a sustainable fish farming industry. Toll-like receptor (TLR) ligands have already been used as good adjuvants in human vaccines. With more understanding of TLR expression, function, and ligand specificity in fish, more efficient adjuvants for fish viral vaccines can be developed. In this paper, we examine all known TLRs in Atlantic salmon (Salmo salar) and demonstrate that head kidney and spleen are the main organs expressing TLRs in salmon. We also show that adherent head kidney leucocytes from salmon are able to respond to many of the known agonists for human TLRs, and that viral infection can induce up-regulation of several TLRs. These findings substantiate these receptors' role in immune responses to pathogens in salmonids making their ligands attractive as vaccine adjuvant candidates. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. IMMUNO-MODULATORY EFFECT OF INACTIVATED EIMERIA TENELLA VACCINE AND LIVE IMPPORTED COCCIDIAL VACCINE ON NEWCASTLE DISEASE VIRUS VACCINA TED BROILER CHICKS

    Directory of Open Access Journals (Sweden)

    Muhammad Akram Muneer, Haji Ahmad Hashmi, Masood Rabbani, Zahid Munir Chaudhry and Ali M. Bahrami

    2001-01-01

    Full Text Available A total of 160 one-day-old broiler chicks were used to evaluate the immunomodulatory effects of an inactivated Eimeria tenella vaccine and a live polyvalent imported antiococcidial vaccine (Coccivac. This study indicated that both of these vaccines did not adversely affect the development of serum antibody against Newcastle disease virus (NDV and the chicks vaccinated with either of the anticoccidial vaccines resisted the virulent NDV challenge. A study of the lymphoid organs such as bursa of fabricuis: thymus and spleen from the experimental chicks indicated that those organs were comparable with those from the chicks not vaccinated with these coccidial vaccines. The overall findings of this study indicate that anticoccidial vaccines do not have any effects on the immune functions of the vaccinates. In fact these vaccines prevented the occurrence of clinical coccidiosis in the vaccinates.

  5. Porphyromonas gulae Activates Unprimed and Gamma Interferon-Primed Macrophages via the Pattern Recognition Receptors Toll-Like Receptor 2 (TLR2), TLR4, and NOD2

    Science.gov (United States)

    Holden, James A.; O'Brien-Simpson, Neil M.; Lenzo, Jason C.; Orth, Rebecca K. H.; Mansell, Ashley

    2017-01-01

    ABSTRACT Porphyromonas gulae is an anaerobic, Gram-negative coccobacillus that has been associated with periodontal disease in companion animals. The aims of this study were to analyze the ligation of pattern recognition receptors by P. gulae and the subsequent activation of macrophages. Exposure of HEK cells transfected with Toll-like receptors (TLRs) or NOD-like receptors to P. gulae resulted in the ligation of TLR2, TLR4, and NOD2. The effects of this engagement of receptors were investigated by measuring the synthesis of nitric oxide (NO), CD86 expression, and inflammatory cytokine production by wild-type, TLR2−/−, and TLR4−/− macrophages. The addition of P. gulae to unprimed and gamma interferon (IFN-γ)-primed (M1 phenotype) macrophages significantly increased the surface expression of CD86, but only M1 macrophages produced nitric oxide. P. gulae-induced expression of CD86 on unprimed macrophages was dependent on both TLR2 and TLR4, but CD86 expression and NO production in M1 macrophages were only TLR2 dependent. P. gulae induced an increase in secretion of interleukin-1α (IL-1α), IL-1β, IL-6, IL-12p70, IL-13, tumor necrosis factor alpha (TNF-α), granulocyte colony-stimulating factor (G-CSF), monocyte chemoattractant protein 1 (MCP-1), and macrophage inflammatory protein 1α (MIP-1α) by M1 macrophages compared to that by unprimed controls. Among these cytokines, secretion of IL-6 and TNF-α by M1 macrophages was dependent on either TLR2 or TLR4. Our data indicate that TLR2 and TLR4 are important for P. gulae activation of unprimed macrophages and that activation and effector functions induced in M1 macrophages by P. gulae are mainly dependent on TLR2. In conclusion, P. gulae induces a strong TLR2-dependent inflammatory M1 macrophage response which may be important in establishing the chronic inflammation associated with periodontal disease in companion animals. PMID:28630066

  6. Porphyromonas gulae Activates Unprimed and Gamma Interferon-Primed Macrophages via the Pattern Recognition Receptors Toll-Like Receptor 2 (TLR2), TLR4, and NOD2.

    Science.gov (United States)

    Holden, James A; O'Brien-Simpson, Neil M; Lenzo, Jason C; Orth, Rebecca K H; Mansell, Ashley; Reynolds, Eric C

    2017-09-01

    Porphyromonas gulae is an anaerobic, Gram-negative coccobacillus that has been associated with periodontal disease in companion animals. The aims of this study were to analyze the ligation of pattern recognition receptors by P. gulae and the subsequent activation of macrophages. Exposure of HEK cells transfected with Toll-like receptors (TLRs) or NOD-like receptors to P. gulae resulted in the ligation of TLR2, TLR4, and NOD2. The effects of this engagement of receptors were investigated by measuring the synthesis of nitric oxide (NO), CD86 expression, and inflammatory cytokine production by wild-type, TLR2 -/- , and TLR4 -/- macrophages. The addition of P. gulae to unprimed and gamma interferon (IFN-γ)-primed (M1 phenotype) macrophages significantly increased the surface expression of CD86, but only M1 macrophages produced nitric oxide. P. gulae- induced expression of CD86 on unprimed macrophages was dependent on both TLR2 and TLR4, but CD86 expression and NO production in M1 macrophages were only TLR2 dependent. P. gulae induced an increase in secretion of interleukin-1α (IL-1α), IL-1β, IL-6, IL-12p70, IL-13, tumor necrosis factor alpha (TNF-α), granulocyte colony-stimulating factor (G-CSF), monocyte chemoattractant protein 1 (MCP-1), and macrophage inflammatory protein 1α (MIP-1α) by M1 macrophages compared to that by unprimed controls. Among these cytokines, secretion of IL-6 and TNF-α by M1 macrophages was dependent on either TLR2 or TLR4. Our data indicate that TLR2 and TLR4 are important for P. gulae activation of unprimed macrophages and that activation and effector functions induced in M1 macrophages by P. gulae are mainly dependent on TLR2. In conclusion, P. gulae induces a strong TLR2-dependent inflammatory M1 macrophage response which may be important in establishing the chronic inflammation associated with periodontal disease in companion animals. Copyright © 2017 American Society for Microbiology.

  7. The HIV-1 envelope transmembrane domain binds TLR2 through a distinct dimerization motif and inhibits TLR2-mediated responses.

    Directory of Open Access Journals (Sweden)

    Eliran Moshe Reuven

    2014-08-01

    Full Text Available HIV-1 uses a number of means to manipulate the immune system, to avoid recognition and to highjack signaling pathways. HIV-1 infected cells show limited Toll-Like Receptor (TLR responsiveness via as yet unknown mechanisms. Using biochemical and biophysical approaches, we demonstrate that the trans-membrane domain (TMD of the HIV-1 envelope (ENV directly interacts with TLR2 TMD within the membrane milieu. This interaction attenuates TNFα, IL-6 and MCP-1 secretion in macrophages, induced by natural ligands of TLR2 both in in vitro and in vivo models. This was associated with decreased levels of ERK phosphorylation. Furthermore, mutagenesis demonstrated the importance of a conserved GxxxG motif in driving this interaction within the membrane milieu. The administration of the ENV TMD in vivo to lipotechoic acid (LTA/Galactosamine-mediated septic mice resulted in a significant decrease in mortality and in tissue damage, due to the weakening of systemic macrophage activation. Our findings suggest that the TMD of ENV is involved in modulation of the innate immune response during HIV infection. Furthermore, due to the high functional homology of viral ENV proteins this function may be a general character of viral-induced immune modulation.

  8. Epithelial expression of TLR4 is modulated in COPD and by steroids, salmeterol and cigarette smoke

    Directory of Open Access Journals (Sweden)

    Dorscheid Delbert R

    2007-11-01

    Full Text Available Abstract The toll-like receptors (TLRs are a key component of host defense in the respiratory epithelium. Cigarette smoking is associated with increased susceptibility to infection, while COPD is characterised by bacterial colonisation and infective exacerbations. We found reduced TLR4 gene expression in the nasal epithelium of smokers compared with non-smoking controls, while TLR2 expression was unchanged. Severe COPD was associated with reduced TLR4 expression compared to less severe disease, with good correlation between nasal and tracheal expression. We went on to examine the effect of potential modulators of TLR4 expression in respiratory epithelium pertinent to airways disease. Using an airway epithelial cell line, we found a dose-dependent downregulation in TLR4 mRNA and protein expression by stimulation with cigarette smoke extracts. Treatment with the corticosteroids fluticasone and dexamethasone resulted in a dose-dependent reduction in TLR4 mRNA and protein. The functional significance of this effect was demonstrated by impaired IL-8 and HBD2 induction in response to LPS. Stimulation with salmeterol (10-6 M caused upregulation of TLR4 membrane protein presentation with no upregulation of mRNA, suggesting a post-translational effect. The effect of dexamethasone and salmeterol in combination was additive, with downregulation of TLR4 gene expression, and no change in membrane receptor expression. Modulation of TLR4 in respiratory epithelium may have important implications for airway inflammation and infection in response to inhaled pathogens.

  9. Identification of the key differential transcriptional responses of human whole blood following TLR2 or TLR4 ligation in-vitro.

    Directory of Open Access Journals (Sweden)

    Simon Blankley

    Full Text Available The use of human whole blood for transcriptomic analysis has potential advantages over the use of isolated immune cells for studying the transcriptional response to pathogens and their products. Whole blood stimulation can be carried out in a laboratory without the expertise or equipment to isolate immune cells from blood, with the added advantage of being able to undertake experiments using very small volumes of blood. Toll like receptors (TLRs are a family of pattern recognition receptors which recognise highly conserved microbial products. Using the TLR2 ligand (Pam3CSK4 and the TLR4 ligand (LPS, human whole blood was stimulated for 0, 1, 3, 6, 12 or 24 hours at which times mRNA was isolated and a comparative microarray was undertaken. A common NFκB transcriptional programme was identified following both TLR2 and TLR4 ligation which peaked at between 3 to 6 hours including upregulation of many of the NFκB family members. In contrast an interferon transcriptional response was observed following TLR4 but not TLR2 ligation as early as 1 hour post stimulation and peaking at 6 hours. These results recapitulate the findings observed in previously published studies using isolated murine and human myeloid cells indicating that in vitro stimulated human whole blood can be used to interrogate the early transcriptional kinetic response of innate cells to TLR ligands. Our study demonstrates that a transcriptomic analysis of mRNA isolated from human whole blood can delineate both the temporal response and the key transcriptional differences following TLR2 and TLR4 ligation.

  10. The TIR-domain containing adaptor TRAM is required for TLR7 mediated RANTES production.

    Directory of Open Access Journals (Sweden)

    Enda Shevlin

    Full Text Available Toll-like receptor 7 (TLR7 plays a vital role in the immune response to ssRNA viruses such as human rhinovirus (HRV and Influenza, against which there are currently no treatments or vaccines with long term efficacy available. Clearly, a more comprehensive understanding of the TLR7 signaling axis will contribute to its molecular targeting. TRIF related adaptor molecule (TRAM plays a vital role in TLR4 signaling by recruiting TRIF to TLR4, followed by endosomal trafficking of the complex and initiation of IRF3 dependent type I interferon production as well as NF-κB dependent pro-inflammatory cytokine production. Towards understanding the molecular mechanisms that regulate TLR7 functionality, we found that TRAM(-/- murine macrophages exhibited a transcriptional and translational impairment in TLR7 mediated RANTES, but not TNFα, production. Suppression of TRAM expression in human macrophages also resulted in an impairment in TLR7 mediated CCL5 and IFN-β, but not TNFα, gene induction. Furthermore, suppression of endogenous human TRAM expression in human macrophages significantly impaired RV16 induced CCL5 and IFNβ, but not TNFα gene induction. Additionally, TRAM-G2A dose-dependently inhibited TLR7 mediated activation of CCL5, IFNβ and IFNα reporter genes. TLR7-mediated phosphorylation and nuclear translocation of IRF3 was impaired in TRAM(-/- cells. Finally, co-immunoprecipitation studies indicated that TRAM physically interacts with MyD88 upon TLR7 stimulation, but not under basal conditions. Our results clearly demonstrate that TRAM plays a, hitherto unappreciated, role in TLR7 signaling through a novel signaling axis containing, but not limited to, MyD88, TRAM and IRF3 towards the activation of anti-viral immunity.

  11. Co-stimulation with TLR3 and TLR21 ligands synergistically up-regulates Th1-cytokine IFN-gamma and regulatory cytokine IL-10 expression in chicken monocytes

    Science.gov (United States)

    Toll-like receptors (TLRs) are the pattern recognition receptors of the innate immune system for various conserved pathogen-associated molecular motifs. The chicken TLR3 and TLR21 (avian equivalent to mammalian TLR9) recognize poly I:C (viral double-stranded RNA) and CpG-ODN (a CpG-motif containing...

  12. BAD-LAMP controls TLR9 trafficking and signalling in human plasmacytoid dendritic cells.

    Science.gov (United States)

    Combes, Alexis; Camosseto, Voahirana; N'Guessan, Prudence; Argüello, Rafael J; Mussard, Julie; Caux, Christophe; Bendriss-Vermare, Nathalie; Pierre, Philippe; Gatti, Evelina

    2017-10-13

    Toll-like receptors (TLR) are essential components of the innate immune system. Several accessory proteins, such as UNC93B1, are required for transport and activation of nucleic acid sensing Toll-like receptors in endosomes. Here, we show that BAD-LAMP (LAMP5) controls TLR9 trafficking to LAMP1 + late endosomes in human plasmacytoid dendritic cells (pDC), leading to NF-κB activation and TNF production upon DNA detection. An inducible VAMP3 +/ LAMP2 +/ LAMP1 - endolysosome compartment exists in pDCs from which TLR9 activation triggers type I interferon expression. BAD-LAMP-silencing enhances TLR9 retention in this compartment and consequent downstream signalling events. Conversely, sustained BAD-LAMP expression in pDCs contributes to their lack of type I interferon production after exposure to a TGF-β-positive microenvironment or isolation from human breast tumours. Hence, BAD-LAMP limits interferon expression in pDCs indirectly, by promoting TLR9 sorting to late endosome compartments at steady state and in response to immunomodulatory cues.TLR9 is highly expressed by plasmacytoid dendritic cells and detects nucleic acids, but to discriminate between host and microbial nucleic acids TLR9 is sorted into different endosomal compartments. Here the authors show that BAD-LAMP limits type 1 interferon responses by sorting TLR9 to late endosomal compartments.

  13. TLR2 ligands induce NF-κB activation from endosomal compartments of human monocytes.

    Directory of Open Access Journals (Sweden)

    Karim J Brandt

    Full Text Available Localization of Toll-like receptors (TLR in subcellular organelles is a major strategy to regulate innate immune responses. While TLR4, a cell-surface receptor, signals from both the plasma membrane and endosomal compartments, less is known about the functional role of endosomal trafficking upon TLR2 signaling. Here we show that the bacterial TLR2 ligands Pam3CSK4 and LTA activate NF-κB-dependent signaling from endosomal compartments in human monocytes and in a NF-κB sensitive reporter cell line, despite the expression of TLR2 at the cell surface. Further analyses indicate that TLR2-induced NF-κB activation is controlled by a clathrin/dynamin-dependent endocytosis mechanism, in which CD14 serves as an important upstream regulator. These findings establish that internalization of cell-surface TLR2 into endosomal compartments is required for NF-κB activation. These observations further demonstrate the need of endocytosis in the activation and regulation of TLR2-dependent signaling pathways.

  14. In Vivo TLR9 Inhibition Attenuates CpG-Induced Myocardial Dysfunction

    Directory of Open Access Journals (Sweden)

    O. Boehm

    2013-01-01

    Full Text Available The involvement of toll-like receptor 9 (TLR9, a receptor for bacterial DNA, in septic cardiac depression has not been clarified in vivo. Thus, the aim of the study was to test possible TLR9 inhibitors (H154-thioate, IRS954-thioate, and chloroquine for their ability to protect the cardiovascular system in a murine model of CpG oligodeoxynucleotide- (ODN- dependent systemic inflammation. Sepsis was induced by i.p. application of the TLR9 agonist 1668-thioate in C57BL/6 wild type (WT and TLR9-deficient (TLR9-D mice. Thirty minutes after stimulation TLR9 antagonists were applied i.v. Survival was monitored up to 18 h after stimulation. Cardiac mRNA expression of inflammatory mediators was analyzed 2 h and 6 h after stimulation with 1668-thioate and hemodynamic parameters were monitored at the later time point. Stimulation with 1668-thioate induced a severe sepsis-like state with significant drop of body temperature and significantly increased mortality in WT animals. Additionally, there was a time-dependent increase of inflammatory mediators in the heart accompanied by development of septic heart failure. These effects were not observed in TLR9-D mice. Inhibition of TLR9 by the suppressive ODN H154-thioate significantly ameliorated cardiac inflammation, preserved cardiac function, and improved survival. This suppressive ODN was the most efficient inhibitor of the tested substances.

  15. Evidence for a developmental role for TLR4 in learning and memory.

    Directory of Open Access Journals (Sweden)

    Eitan Okun

    Full Text Available Toll-like receptors (TLRs play essential roles in innate immunity and increasing evidence indicates that these receptors are expressed in neurons, astrocytes and microglia in the brain where they mediate responses to infection, stress and injury. Very little is known about the roles of TLRs in cognition. To test the hypothesis that TLR4 has a role in hippocampus-dependent spatial learning and memory, we used mice deficient for TLR4 and mice receiving chronic TLR4 antagonist infusion to the lateral ventricles in the brain. We found that developmental TLR4 deficiency enhances spatial reference memory acquisition and memory retention, impairs contextual fear-learning and enhances motor functions, traits that were correlated with CREB up-regulation in the hippocampus. TLR4 antagonist infusion into the cerebral ventricles of adult mice did not affect cognitive behavior, but instead affected anxiety responses. Our findings indicate a developmental role for TLR4 in shaping spatial reference memory, and fear learning and memory. Moreover, we show that central TLR4 inhibition using a TLR4 antagonist has no discernible physiological role in regulating spatial and contextual hippocampus-dependent cognitive behavior.

  16. TLR4 links podocytes with the innate immune system to mediate glomerular injury

    DEFF Research Database (Denmark)

    Banas, Miriam C; Banas, Bernhard; Hudkins, Kelly L

    2008-01-01

    profile of chemokines. In conclusion, it was demonstrated that TLR4 is constitutively expressed by podocytes and is upregulated in MPGN, where it may mediate glomerular injury by modulating expression of chemokines; therefore, TLR4 may link podocytes with the innate immune system to mediate MPGN triggered...... by the deposition of immune complexes....

  17. TLR-mediated NF-kB-dependent cytokine production is differently affected by HIV therapeutics

    DEFF Research Database (Denmark)

    Melchjorsen, Jesper; Paludan, Søren Riis; Mogensen, Trine

      Pathogen-recognizing Toll-like receptors 2 (TLR2) and TLR4 are known to recognize a number of pathogens, including E.Coli, S. Pneumonia and N. Meningococcus. We have studied whether a number of HIV therapeutics affect immediate proinflammatory cytokine responses in cell cultures. Preliminary...

  18. Divergent effects of Tenofovir and Retrovir (AZT) on TLR-mediated cytokine production

    DEFF Research Database (Denmark)

    Melchjorsen, Jesper; Tolstrup, Martin; Paludan, Søren Riis

      Pathogen-recognizing Toll-like receptors 2 (TLR2) and TLR4 are known to recognize a number of pathogens, including E.Coli, S. Pneumoniae and N. Meningitidis. We have studied whether a number of HIV therapeutics affect immediate proinflammatory cytokine responses in cell cultures. Preliminary...

  19. A role for TLR10 in obesity and adipose tissue morphology

    NARCIS (Netherlands)

    Boutens, Lily; Mirea, Andreea Manuela; Munckhof, van den Inge; Doppenberg-Oosting, Marije; Jaeger, Martin; Hijmans, Anneke; Netea, Mihai G.; Joosten, Leo A.B.; Stienstra, Rinke

    2018-01-01

    Toll like receptors (TLRs) are expressed in adipose tissue and promote adipose tissue inflammation during obesity. Recently, anti-inflammatory properties have been attributed to TLR10 in myeloid cells, the only member of the TLR family with inhibitory activity. In order to assess whether

  20. In Vivo Lipopolysaccharide Exposure of Human Blood Leukocytes Induces Cross-Tolerance to Multiple TLR Ligands

    NARCIS (Netherlands)

    de Vos, Alex F.; Pater, Jennie M.; van den Pangaart, Petra S.; de Kruif, Martijn D.; van 't Veer, Cornelis; van der Poll, Tom

    2009-01-01

    In vitro and in vivo experiments in mice have shown that exposure of cells to the TLR4 ligand LPS induces tolerance toward a second exposure to LPS and induces cross-tolerance to certain other TLR ligands. Recently, we found that LPS tolerance in experimental human endotoxemia and Gram-negative

  1. TLR5 signaling, commensal microbiota and systemic tumor promoting inflammation: the three parcae of malignant progression.

    Science.gov (United States)

    Rutkowski, Melanie R; Conejo-Garcia, Jose R

    2015-08-01

    We have reported that TLR5-mediated recognition of commensal microbiota modulates systemic tumor-promoting inflammation and malignant progression of tumors at distal locations. Approximately 7-10% of the general population harbors a deleterious single nucleotide polymorphism in TLR5, implicating a novel role for genetic variation during the initiation and progression of cancer.

  2. Determination of the physiological 2:2 TLR5:flagellin activation stoichiometry revealed by the activity of a fusion receptor

    International Nuclear Information System (INIS)

    Ivičak-Kocjan, Karolina; Panter, Gabriela; Benčina, Mojca; Jerala, Roman

    2013-01-01

    Highlights: •The chimeric protein fusing flagellin to the TLR5 ectodomain is constitutively active. •Mutation P736H within the BB-loop of TLR5 TIR domain renders the receptor inactive. •The R90D mutation in flagellin inactivated autoactivation of the chimeric protein. •The 2:2 stoichiometry of the TLR5:flagellin complex is physiologically relevant. -- Abstract: Toll-like receptor 5 (TLR5) recognizes flagellin of most flagellated bacteria, enabling activation of the MyD88-dependent signaling pathway. The recently published crystal structure of a truncated zebrafish TLR5 ectodomain in complex with an inactive flagellin fragment indicated binding of two flagellin molecules to a TLR5 homodimer, however this complex did not dimerize in solution. In the present study, we aimed to determine the physiological stoichiometry of TLR5:flagellin activation by the use of a chimeric protein composed of an active flagellin fragment linked to the N-terminus of human TLR5 (SF-TLR5). This construct was constitutively active. Inactivation by the R90D mutation within flagellin demonstrated that autoactivation of the chimeric protein depended solely on the specific interaction between TLR5 and flagellin. Addition of wild-type hTLR5 substantially lowered autoactivation of SF-TLR5 in a concentration dependent manner, an effect which was reversible by the addition of exogenous Salmonella typhimurium flagellin, indicating the biological activity of a TLR5:flagellin complex with a 2:2 stoichiometry. These results, in addition to the combinations of inactive P736H mutation within the BB-loop of the TIR domain of TLR5 and SF-TLR5, further confirm the mechanism of TLR5 activation

  3. Determination of the physiological 2:2 TLR5:flagellin activation stoichiometry revealed by the activity of a fusion receptor

    Energy Technology Data Exchange (ETDEWEB)

    Ivičak-Kocjan, Karolina; Panter, Gabriela; Benčina, Mojca [Laboratory of Biotechnology, National Institute of Chemistry, 1000 Ljubljana (Slovenia); The Centre of Excellence EN-FIST, 1000 Ljubljana (Slovenia); Jerala, Roman, E-mail: roman.jerala@ki.si [Laboratory of Biotechnology, National Institute of Chemistry, 1000 Ljubljana (Slovenia); The Centre of Excellence EN-FIST, 1000 Ljubljana (Slovenia); The Faculty of Chemistry and Chemical Technology, University of Ljubljana, 1000 Ljubljana (Slovenia)

    2013-05-24

    Highlights: •The chimeric protein fusing flagellin to the TLR5 ectodomain is constitutively active. •Mutation P736H within the BB-loop of TLR5 TIR domain renders the receptor inactive. •The R90D mutation in flagellin inactivated autoactivation of the chimeric protein. •The 2:2 stoichiometry of the TLR5:flagellin complex is physiologically relevant. -- Abstract: Toll-like receptor 5 (TLR5) recognizes flagellin of most flagellated bacteria, enabling activation of the MyD88-dependent signaling pathway. The recently published crystal structure of a truncated zebrafish TLR5 ectodomain in complex with an inactive flagellin fragment indicated binding of two flagellin molecules to a TLR5 homodimer, however this complex did not dimerize in solution. In the present study, we aimed to determine the physiological stoichiometry of TLR5:flagellin activation by the use of a chimeric protein composed of an active flagellin fragment linked to the N-terminus of human TLR5 (SF-TLR5). This construct was constitutively active. Inactivation by the R90D mutation within flagellin demonstrated that autoactivation of the chimeric protein depended solely on the specific interaction between TLR5 and flagellin. Addition of wild-type hTLR5 substantially lowered autoactivation of SF-TLR5 in a concentration dependent manner, an effect which was reversible by the addition of exogenous Salmonella typhimurium flagellin, indicating the biological activity of a TLR5:flagellin complex with a 2:2 stoichiometry. These results, in addition to the combinations of inactive P736H mutation within the BB-loop of the TIR domain of TLR5 and SF-TLR5, further confirm the mechanism of TLR5 activation.

  4. TLR2, TLR4 and the MYD88 signaling pathway are crucial for neutrophil migration in acute kidney injury induced by sepsis.

    Directory of Open Access Journals (Sweden)

    Angela Castoldi

    Full Text Available The aim of this study was to investigate the role of TLR2, TLR4 and MyD88 in sepsis-induced AKI. C57BL/6 TLR2(-/-, TLR4(-/- and MyD88(-/- male mice were subjected to sepsis by cecal ligation and puncture (CLP. Twenty four hours later, kidney tissue and blood samples were collected for analysis. The TLR2(-/-, TLR4(-/- and MyD88(-/- mice that were subjected to CLP had preserved renal morphology, and fewer areas of hypoxia and apoptosis compared with the wild-type C57BL/6 mice (WT. MyD88(-/- mice were completely protected compared with the WT mice. We also observed reduced expression of proinflammatory cytokines in the kidneys of the knockout mice compared with those of the WT mice and subsequent inhibition of increased vascular permeability in the kidneys of the knockout mice. The WT mice had increased GR1(+low cells migration compared with the knockout mice and decreased in GR1(+high cells migration into the peritoneal cavity. The TLR2(-/-, TLR4(-/-, and MyD88(-/- mice had lower neutrophil infiltration in the kidneys. Depletion of neutrophils in the WT mice led to protection of renal function and less inflammation in the kidneys of these mice. Innate immunity participates in polymicrobial sepsis-induced AKI, mainly through the MyD88 pathway, by leading to an increased migration of neutrophils to the kidney, increased production of proinflammatory cytokines, vascular permeability, hypoxia and apoptosis of tubular cells.

  5. Porphyromonas gingivalis evasion of autophagy and intracellular killing by human myeloid dendritic cells involves DC-SIGN-TLR2 crosstalk.

    Science.gov (United States)

    El-Awady, Ahmed R; Miles, Brodie; Scisci, Elizabeth; Kurago, Zoya B; Palani, Chithra D; Arce, Roger M; Waller, Jennifer L; Genco, Caroline A; Slocum, Connie; Manning, Matthew; Schoenlein, Patricia V; Cutler, Christopher W

    2015-02-01

    Signaling via pattern recognition receptors (PRRs) expressed on professional antigen presenting cells, such as dendritic cells (DCs), is crucial to the fate of engulfed microbes. Among the many PRRs expressed by DCs are Toll-like receptors (TLRs) and C-type lectins such as DC-SIGN. DC-SIGN is targeted by several major human pathogens for immune-evasion, although its role in intracellular routing of pathogens to autophagosomes is poorly understood. Here we examined the role of DC-SIGN and TLRs in evasion of autophagy and survival of Porphyromonas gingivalis in human monocyte-derived DCs (MoDCs). We employed a panel of P. gingivalis isogenic fimbriae deficient strains with defined defects in Mfa-1 fimbriae, a DC-SIGN ligand, and FimA fimbriae, a TLR2 agonist. Our results show that DC-SIGN dependent uptake of Mfa1+P. gingivalis strains by MoDCs resulted in lower intracellular killing and higher intracellular content of P. gingivalis. Moreover, Mfa1+P. gingivalis was mostly contained within single membrane vesicles, where it survived intracellularly. Survival was decreased by activation of TLR2 and/or autophagy. Mfa1+P. gingivalis strain did not induce significant levels of Rab5, LC3-II, and LAMP1. In contrast, P. gingivalis uptake through a DC-SIGN independent manner was associated with early endosomal routing through Rab5, increased LC3-II and LAMP-1, as well as the formation of double membrane intracellular phagophores, a characteristic feature of autophagy. These results suggest that selective engagement of DC-SIGN by Mfa-1+P. gingivalis promotes evasion of antibacterial autophagy and lysosome fusion, resulting in intracellular persistence in myeloid DCs; however TLR2 activation can overcome autophagy evasion and pathogen persistence in DCs.

  6. Regulator of calcineurin 1 differentially regulates TLR-dependent MyD88 and TRIF signaling pathways.

    Directory of Open Access Journals (Sweden)

    Zheng Pang

    Full Text Available Toll-like receptors (TLRs recognize the conserved molecular patterns in microorganisms and trigger myeloid differentiation primary response 88 (MyD88 and/or TIR-domain-containing adapter-inducing interferon-β (TRIF pathways that are critical for host defense against microbial infection. However, the molecular mechanisms that govern TLR signaling remain incompletely understood. Regulator of calcineurin-1 (RCAN1, a small evolutionarily conserved protein that inhibits calcineurin phosphatase activity, suppresses inflammation during Pseudomonas aeruginosa infection. Here, we define the roles for RCAN1 in P. aeruginosa lipopolysaccharide (LPS-activated TLR4 signaling. We compared the effects of P. aeruginosa LPS challenge on bone marrow-derived macrophages from both wild-type and RCAN1-deficient mice and found that RCAN1 deficiency increased the MyD88-NF-κB-mediated cytokine production (IL-6, TNF and MIP-2, whereas TRIF-interferon-stimulated response elements (ISRE-mediated cytokine production (IFNβ, RANTES and IP-10 was suppressed. RCAN1 deficiency caused increased IκBα phosphorylation and NF-κB activity in the MyD88-dependent pathway, but impaired ISRE activation and reduced IRF7 expression in the TRIF-dependent pathway. Complementary studies of a mouse model of P. aeruginosa LPS-induced acute pneumonia confirmed that RCAN1-deficient mice displayed greatly enhanced NF-κB activity and MyD88-NF-κB-mediated cytokine production, which correlated with enhanced pulmonary infiltration of neutrophils. By contrast, RCAN1 deficiency had little effect on the TRIF pathway in vivo. These findings demonstrate a novel regulatory role of RCAN1 in TLR signaling, which differentially regulates MyD88 and TRIF pathways.

  7. Arctigenin Induces an Activation Response in Porcine Alveolar Macrophage Through TLR6-NOX2-MAPKs Signaling Pathway

    Science.gov (United States)

    Lu, Zheng; Chang, Lingling; Du, Qian; Huang, Yong; Zhang, Xiujuan; Wu, Xingchen; Zhang, Jie; Li, Ruizhen; Zhang, Zelin; Zhang, Wenlong; Zhao, Xiaomin; Tong, Dewen

    2018-01-01

    Arctigenin (ARG), one of the most active ingredients abstracted from seeds of Arctium lappa L., has been proved to exert promising biological activities such as immunomodulatory, anti-viral, and anti-cancer etc. However, the mechanism behind its immunomodulatory function still remains elusive to be further investigated. In this study, we found that ARG had no significant effects on the cell proliferation in both porcine alveolar macrophage cell line (3D4/21) and primary porcine derived alveolar macrophage. It remarkably increased the expression and secretion of the two cytokines including tumor necrosis factor-alpha (TNF-α) and transforming growth factor beta1 (TGF-β1) in a dose-dependent manner with the concomitant enhancement of phagocytosis, which are the indicators of macrophage activation. ARG also elevated the intracellular reactive oxygen species (ROS) production by activating NOX2-based NADPH oxidase. Furthermore, inhibition of ROS generation by diphenyliodonium and apocynin significantly suppressed ARG-induced cytokine secretion and phagocytosis increase, indicating the requirement of ROS for the porcine alveolar macrophage activation. In addition, TLR6-My88 excitation, p38 MAPK and ERK1/2 phosphorylation were all involved in the process. As blocking TLR6 receptor dramatically attenuated the NOX2 oxidase activation, cytokine secretion and phagocytosis increase. Inhibiting ROS generation almost abolished p38 and ERK1/2 phosphorylation, and the cytokine secretion could also be remarkably reduced by p38 and ERK1/2 inhibitors (SB203580 and UO126). Our finding gave a new insight of understanding that ARG could improve the immune-function of porcine alveolar macrophages through TLR6-NOX2 oxidase-MAPKs signaling pathway.

  8. Fetal and Placental DNA Stimulation of TLR9: A Mechanism Possibly Contributing to the Pro-inflammatory Events During Parturition.

    Science.gov (United States)

    Goldfarb, Ilona Telefus; Adeli, Sharareh; Berk, Tucker; Phillippe, Mark

    2018-05-01

    While there is evidence for a relationship between cell-free fetal DNA (cffDNA) and parturition, questions remain regarding whether cffDNA could trigger a pro-inflammatory response on the pathway to parturition. We hypothesized that placental and/or fetal DNA stimulates toll-like receptor 9 (TLR9) leading to secretion of pro-inflammatory cytokines by macrophage cells. Four in vitro DNA stimulation studies were performed using RAW 264.7 mouse peritoneal macrophage cells incubated in media containing the following DNA particles: an oligodeoxynucleotide (ODN2395), intact genomic DNA (from mouse placentas, fetuses and adult liver), mouse DNA complexed with DOTAP (a cationic liposome forming compound), and telomere-depleted mouse DNA. Interleukin 6 (IL6) secretion was measured in the media by enzyme-linked immunosorbent assay; and the cell pellet was homogenized for protein content (picograms IL6/mg protein). Robust IL6 secretion was observed in response to ODN2395 (a CpG-rich TLR9 agonist), mouse DNA-DOTAP complexes, and telomere-depleted mouse DNA in concentrations of 5 to 15 μg/mL. In contrast, ODN A151 (containing telomere sequence motifs), intact genomic mouse DNA, and restriction enzyme-digested DNA had no effect on IL6 secretion. The IL6 response was significantly inhibited by chloroquine (10 μg/mL), thereby confirming the important role for TLR9 in the response by macrophage cells. DNA derived from mouse placentas and fetuses, and depleted of telomeric sequences, stimulates a robust pro-inflammatory response by macrophage cells, thereby supporting the hypothesis that cffDNA is able to stimulate an innate immune response that could trigger the onset of parturition. These findings are of clinical importance, as we search for effective treatment/prevention of preterm parturition.

  9. Arctigenin Induces an Activation Response in Porcine Alveolar Macrophage Through TLR6-NOX2-MAPKs Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Zheng Lu

    2018-05-01

    Full Text Available Arctigenin (ARG, one of the most active ingredients abstracted from seeds of Arctium lappa L., has been proved to exert promising biological activities such as immunomodulatory, anti-viral, and anti-cancer etc. However, the mechanism behind its immunomodulatory function still remains elusive to be further investigated. In this study, we found that ARG had no significant effects on the cell proliferation in both porcine alveolar macrophage cell line (3D4/21 and primary porcine derived alveolar macrophage. It remarkably increased the expression and secretion of the two cytokines including tumor necrosis factor-alpha (TNF-α and transforming growth factor beta1 (TGF-β1 in a dose-dependent manner with the concomitant enhancement of phagocytosis, which are the indicators of macrophage activation. ARG also elevated the intracellular reactive oxygen species (ROS production by activating NOX2-based NADPH oxidase. Furthermore, inhibition of ROS generation by diphenyliodonium and apocynin significantly suppressed ARG-induced cytokine secretion and phagocytosis increase, indicating the requirement of ROS for the porcine alveolar macrophage activation. In addition, TLR6-My88 excitation, p38 MAPK and ERK1/2 phosphorylation were all involved in the process. As blocking TLR6 receptor dramatically attenuated the NOX2 oxidase activation, cytokine secretion and phagocytosis increase. Inhibiting ROS generation almost abolished p38 and ERK1/2 phosphorylation, and the cytokine secretion could also be remarkably reduced by p38 and ERK1/2 inhibitors (SB203580 and UO126. Our finding gave a new insight of understanding that ARG could improve the immune-function of porcine alveolar macrophages through TLR6-NOX2 oxidase-MAPKs signaling pathway.

  10. Arctigenin Induces an Activation Response in Porcine Alveolar Macrophage Through TLR6-NOX2-MAPKs Signaling Pathway.

    Science.gov (United States)

    Lu, Zheng; Chang, Lingling; Du, Qian; Huang, Yong; Zhang, Xiujuan; Wu, Xingchen; Zhang, Jie; Li, Ruizhen; Zhang, Zelin; Zhang, Wenlong; Zhao, Xiaomin; Tong, Dewen

    2018-01-01

    Arctigenin (ARG), one of the most active ingredients abstracted from seeds of Arctium lappa L. , has been proved to exert promising biological activities such as immunomodulatory, anti-viral, and anti-cancer etc. However, the mechanism behind its immunomodulatory function still remains elusive to be further investigated. In this study, we found that ARG had no significant effects on the cell proliferation in both porcine alveolar macrophage cell line (3D4/21) and primary porcine derived alveolar macrophage. It remarkably increased the expression and secretion of the two cytokines including tumor necrosis factor-alpha (TNF-α) and transforming growth factor beta1 (TGF-β1) in a dose-dependent manner with the concomitant enhancement of phagocytosis, which are the indicators of macrophage activation. ARG also elevated the intracellular reactive oxygen species (ROS) production by activating NOX2-based NADPH oxidase. Furthermore, inhibition of ROS generation by diphenyliodonium and apocynin significantly suppressed ARG-induced cytokine secretion and phagocytosis increase, indicating the requirement of ROS for the porcine alveolar macrophage activation. In addition, TLR6-My88 excitation, p38 MAPK and ERK1/2 phosphorylation were all involved in the process. As blocking TLR6 receptor dramatically attenuated the NOX2 oxidase activation, cytokine secretion and phagocytosis increase. Inhibiting ROS generation almost abolished p38 and ERK1/2 phosphorylation, and the cytokine secretion could also be remarkably reduced by p38 and ERK1/2 inhibitors (SB203580 and UO126). Our finding gave a new insight of understanding that ARG could improve the immune-function of porcine alveolar macrophages through TLR6-NOX2 oxidase-MAPKs signaling pathway.

  11. ΔNp63 controls a TLR3-mediated mechanism that abundantly provides thymic stromal lymphopoietin in atopic dermatitis.

    Directory of Open Access Journals (Sweden)

    Terufumi Kubo

    Full Text Available In the skin lesions of atopic dermatitis (AD, keratinocytes release large quantities of thymic stromal lymphopoietin (TSLP, causing unfavorable inflammation along with skin damage. Nevertheless, how TSLP influences keratinocytes themselves is still unknown. In this study, we showed that ΔNp63, a p53-homologue, predominantly expressed in keratinocytes regulated the receptor complex of TSLP, which determines susceptibility to self-derived TSLP. Expression of TSLP receptors in skin tissues and keratinocytes was assessed by immunohistochemistry and quantitative RT-PCR, and in vitro studies were also performed to examine the functional relevance of ΔNp63 in the expression of TSLP receptors and the constituting autocrine and/or paracrine pathway of TSLP under the condition of stimuli to innate receptors sensing cell damage. The results showed that normal keratinocytes in the upper epidermis preferentially expressed TSLP receptors and conversely lacked ΔNp63, which has an inhibitory effect on the expression of TSLP receptors. Interestingly, the epidermis of AD lesions was found to abundantly contain keratinocytes with low or undetectable levels of ΔNp63 (ΔNp63(lo/-. Moreover, in the absence of ΔNp63, keratinocytes readily presented TSLP and other cytokines by stimuli through Toll-like receptor 3 (TLR3. Together with the evidence that extrinsic TSLP itself augments TSLP production by keratinocytes without ΔNp63, the results indicate that ΔNp63(lo/- keratinocytes generate TSLP through a putative autocrine and/or paracrine pathway upon TLR3 stimulation within AD lesions, since moieties of damaged cells and pathogens stimulate TLR3.

  12. TLR4, NOD1 and NOD2 Mediate Immune Recognition of Putative Newly-Identified Periodontal Pathogens

    Science.gov (United States)

    Schaff, Riley A.; Hao, Jie; Morelli, Thiago; Kinney, Janet S.; Gerow, Elizabeth; Sheridan, Rachel; Rodrigues, Vinicius; Paster, Bruce J.; Inohara, Naohiro; Giannobile, William V.

    2015-01-01

    SUMMARY Periodontitis is a polymicrobial inflammatory disease that results from the interaction between the oral microbiota and the host immunity. While the innate immune response is important for disease initiation and progression, the innate immune receptors that recognize both classical and putative periodontal pathogens that elicit an immune response have not been elucidated. By using the Human Oral Microbe Identification Microarray (HOMIM), we identified multiple predominant oral bacterial species in human plaque biofilm that strongly associate with severe periodontitis. Ten of the identified species were evaluated in greater depth, 6 being classical pathogens and 4 putative novel pathogens. Using human peripheral blood monocytes (HPBM) and murine bone marrow–derived macrophages (BMDM) from wild-type (WT) and toll-like receptor (TLR)-specific and MyD88 knockouts (KOs), we demonstrated that heat-killed Campylobacter concisus, Campylobacter rectus, Selenomonas infelix, Porphyromonas endodontalis, Porphyromonas gingivalis, and Tannerella forsythia mediate high immunostimulatory activity. C. concisus, C. rectus, and S. infelix exhibited robust TLR4 stimulatory activity. Studies using mesothelial cells from WT and NOD1-specific KOs and NOD2-expressing human embryonic kidney (HEK) cells demonstrated that Eubacterium saphenum, Eubacterium nodatum and Filifactor alocis exhibit robust NOD1 stimulatory activity, and that Porphyromonas endodontalis and Parvimonas micra have the highest NOD2-stimulatory activity. These studies allowed us to provide important evidence on newly-identified putative pathogens in periodontal disease pathogenesis showing that these bacteria exhibit different immunostimulatory activity via TLR4, NOD1, and NOD2 (Clinicaltrials.gov NCT01154855). PMID:26177212

  13. DMPD: TLR9 as a key receptor for the recognition of DNA. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18262306 TLR9 as a key receptor for the recognition of DNA. Kumagai Y, Takeuchi O, ...TLR9 as a key receptor for the recognition of DNA. PubmedID 18262306 Title TLR9 as a key receptor for the recognition

  14. Cellular uptake of exogenous calcineurin B is dependent on TLR4/MD2/CD14 complexes, and CnB is an endogenous ligand of TLR4.

    Science.gov (United States)

    Yang, Jinju; Qin, Nannan; Zhang, Hongwei; Yang, Rui; Xiang, Benqiong; Wei, Qun

    2016-04-19

    Our previous research showed that recombinant calcineurin B (rhCnB) stimulates cytokine secretion by immune cells, probably through TLR4. Exogenous CnB can be incorporated into many different tumour cells in vitro, but the mode of uptake and receptors required remain unknown. Here, we report that exogenous CnB is taken up by cells in a time- and concentration-dependent manner via clathrin-dependent receptor-mediated internalization. Our findings further confirm that uptake is mediated by the TLR4/MD2 complex together with the co-receptor CD14. The MST results revealed a high affinity between CnB and the TLR4 receptor complex. No binding was detected between CnB and LPS. CnB inhibited the uptake of LPS, and LPS also inhibited the uptake of CnB. These results indicate that the uptake of exogenous CnB did not occur through LPS and that CnB was not a chaperone of LPS. Thus, we conclude that TLR4 receptor complexes were required for the recognition and internalization of exogenous CnB. CnB could be a potential endogenous ligand of TLR4 and function as an agonist of TLR4. These properties of CnB support its potential for development as an anti-cancer drug.

  15. Purinergic signaling to terminate TLR responses in macrophages

    Directory of Open Access Journals (Sweden)

    Kajal eHamidzadeh

    2016-03-01

    Full Text Available Macrophages undergo profound physiological alterations when they encounter pathogen associated molecular patterns (PAMPs. These alterations can result in the elaboration of cytokines and mediators that promote immune responses and contribute to the clearance of pathogens. These innate immune responses by myeloid cells are transient. The termination of these secretory responses is not due to the dilution of stimuli, but rather to the active down-regulation of innate responses induced by the very PAMPs that initiated them. Here we describe a purinergic autoregulatory program whereby TLR-stimulated macrophages control their activation state. In this program, TLR stimulated macrophages undergo metabolic alterations that result in the production of ATP and its release through membrane pannexin channels. This purine nucleotide is rapidly hydrolyzed to adenosine by ectoenzymes on the macrophage surface, CD39 and CD73. Adenosine then signals through the P1 class of seven transmembrane receptors to induce a regulatory state that is characterized by the down-regulation of inflammatory cytokines and the production of anti-inflammatory cytokines and growth factors. This purinergic autoregulatory system mitigates the collateral damage that would be caused by the prolonged activation of macrophages, and rather allows the macrophage to maintain homeostasis. The transient activation of macrophages can be prolonged by treating macrophages with IFN-γ. IFN-γ treated macrophages become less sensitive to the regulatory effects of adenosine, allowing them to sustain macrophage activation for the duration of an adaptive immune response.

  16. TLR4 has a TP53-dependent dual role in regulating breast cancer cell growth.

    Science.gov (United States)

    Haricharan, Svasti; Brown, Powel

    2015-06-23

    Breast cancer is a leading cause of cancer-related death, and it is important to understand pathways that drive the disease to devise effective therapeutic strategies. Our results show that Toll-like receptor 4 (TLR4) drives breast cancer cell growth differentially based on the presence of TP53, a tumor suppressor. TP53 is mutationally inactivated in most types of cancer and is mutated in 30-50% of diagnosed breast tumors. We demonstrate that TLR4 activation inhibits growth of TP53 wild-type cells, but promotes growth of TP53 mutant breast cancer cells by regulating proliferation. This differential effect is mediated by changes in tumor cell cytokine secretion. Whereas TLR4 activation in TP53 mutant breast cancer cells increases secretion of progrowth cytokines, TLR4 activation in TP53 wild-type breast cancer cells increases type I IFN (IFN-γ) secretion, which is both necessary and sufficient for mediating TLR4-induced growth inhibition. This study identifies a novel dichotomous role for TLR4 as a growth regulator and a modulator of tumor microenvironment in breast tumors. These results have translational relevance, demonstrating that TP53 mutant breast tumor growth can be suppressed by pharmacologic TLR4 inhibition, whereas TLR4 inhibitors may in fact promote growth of TP53 wild-type tumors. Furthermore, using data generated by The Cancer Genome Atlas consortium, we demonstrate that the effect of TP53 mutational status on TLR4 activity may extend to ovarian, colon, and lung cancers, among others, suggesting that the viability of TLR4 as a therapeutic target depends on TP53 status in many different tumor types.

  17. Culture supernatants of oral cancer cells induce impaired IFN-α production of pDCs partly through the down-regulation of TLR-9 expression.

    Science.gov (United States)

    Han, Nannan; Zhang, Zun; Jv, Houyu; Hu, Jingzhou; Ruan, Min; Zhang, Chenping

    2018-06-05

    The aim of the present study was to investigate whether tumor-derived supernatants down-regulate the immune function of plasmacytoid dendritic cells (pDCs) in oral cancer and the potential molecular mechanisms of this effect. Immunohistochemistry (IHC) and flow cytometry were used to detect tumor-infiltrating and peripheral blood pDCs. MTS and flow cytometry were employed to evaluate the immune response of CD4 + T cells. Real-time PCR and ELISA assays were used to identify TLR-7 and TLR-9 expression, IFN-α production and tumor-secreted soluble cytokines. The proportion of pDCs (0.121%±0.043%) was significantly higher in Oral squamous cell carcinoma (OSCC) samples than in normal tissue (0.023%±0.016%) (P = 0.021). TLR9 mRNA was significantly lower in tumor-infiltrating pDCs and positively correlated to low IFN-α production (r = 0.956; Poral cancer cells negatively regulated TLR9 mRNA expression and the subsequent IFN-α production of pDCs, which inhibited the immune response of CD4 + T cells. The neutralizing antibodies blocking assay showed that the specific inhibitory effect of pDC functionality was associated with the soluble fraction of the oral cancer environment, which is mainly mediated by IL-10 and TGF-β cooperation. Tumor-derived supernatants may impair the function of tumor-infiltrating pDCs, which subsequently decreases the immune response of CD4 + T cells in human oral cancer through TGF-β- and IL-10- dependent mechanisms. Careful manipulation of these impaired pDCs may help develop an important alternative immunotherapy for the treatment of oral cancer. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. MAPK/p38 regulation of cytoskeleton rearrangement accelerates induction of macrophage activation by TLR4, but not TLR3.

    Science.gov (United States)

    Bian, Hongjun; Li, Feifei; Wang, Wenwen; Zhao, Qi; Gao, Shanshan; Ma, Jincai; Li, Xiao; Ren, Wanhua; Qin, Chengyong; Qi, Jianni

    2017-11-01

    Toll-like receptor 3 (TLR3) and TLR4 utilize adaptor proteins to activate mitogen‑activated protein kinase (MAPK), resulting in the acute but transient inflammatory response aimed at the clearance of pathogens. In the present study, it was demonstrated that macrophage activation by lipopolysaccharide (LPS) or poly(I:C), leading to changes in cell morphology, differed significantly between the mouse macrophage cell line RAW264.7 and mouse primary peritoneal macrophages. Moreover, the expression of α- and β-tubulin was markedly decreased following LPS stimulation. By contrast, α- and β-tubulin expression were only mildly increased following poly(I:C) treatment. However, the expression of β-actin and GAPDH was not significantly affected. Furthermore, it was verified that vincristine pretreatment abrogated the cytoskeleton rearrangement and decreased the synthesis and secretion of proinflammatory cytokines and migration of macrophages caused by LPS. Finally, it was observed that the MAPK/p38 signaling pathway regulating cytoskeleton rearrangement may participate in LPS‑induced macrophage cytokine production and migration. Overall, the findings of the present study indicated that MAPK/p38 regulation of the cytoskeleton, particularly tubulin proteins, plays an important role in LPS-induced inflammatory responses via alleviating the synthesis and secretion of proinflammatory cytokines and inhibiting the migration of macrophages.

  19. Estudos anatômicos de folhas de espécies de plantas daninhas de grande ocorrência no Brasil: IV - Amaranthus deflexus, Amaranthus spinosus, Alternanthera tenella e Euphorbia heterophylla Leaf anatomical studies in weed species widely common in Brazil: IV - Amaranthus deflexus, Amaranthus spinosus, Alternanthera tenella and Euphorbia heterophylla

    Directory of Open Access Journals (Sweden)

    E.A. Ferreira

    2003-08-01

    Full Text Available Neste trabalho é apresentado um estudo da anatomia das folhas de espécies de plantas daninhas de grande ocorrência no Brasil: Amaranthus deflexus, Amaranthus spinosus, Alternanthera tenella e Euphorbia heterophylla, visando melhor compreensão das barreiras que cada espécie impõe à penetração dos herbicidas e outros compostos utilizados em aplicações foliares. As folhas completamente expandidas do terceiro ao quinto nó foram coletadas de plantas de ocorrência espontânea no campo. Das folhas de cada espécie foram obtidas três amostras da região mediana, com aproximadamente 1 cm², as quais foram utilizadas em estudos da estrutura, clarificação e em observações em microscópio eletrônico de varredura. Todas as espécies avaliadas são anfiestomáticas. As principais barreiras foliares potenciais à penetração de herbicidas observadas nas plantas daninhas A. deflexus e A. spinosus foram, respectivamente, grande espessura da cutícula da face adaxial e da cutícula das duas faces. Já em relação a A. tenella, grande espessura da cutícula das duas faces, elevado teor de cera epicuticular e alta densidade tricomática foram os principais obstáculos potenciais detectados. E. heterophylla apresentou como possíveis principais barreiras foliares à penetração de agroquímicos o alto teor de cera epicuticular, a elevada densidade de laticíferos e a grande espessura da cutícula da face adaxial.This research aimed to study the leaf anatomy of the weed species Amaranthus deflexus, Amaranthus spinosus, Alternanthera tenella and Euphorbia heterophylla, widely known in Brazil, to acquire a better understanding of the barriers each species imposes to herbicide penetration, and to other substances used for leaf spraying. Completely expanded leaves from the third to the fifth nodes were collected from spontaneous plants in the field. Three samples approximately 1cm², were removed from the medium portion of the leaves, from each

  20. Contrasting roles for TLR ligands in HIV-1 pathogenesis.

    Directory of Open Access Journals (Sweden)

    Beda Brichacek

    2010-09-01

    Full Text Available The first line of a host's response to various pathogens is triggered by their engagement of cellular pattern recognition receptors (PRRs. Binding of microbial ligands to these receptors leads to the induction of a variety of cellular factors that alter intracellular and extracellular environment and interfere directly or indirectly with the life cycle of the triggering pathogen. Such changes may also affect any coinfecting microbe. Using ligands to Toll-like receptors (TLRs 5 and 9, we examined their effect on human immunodeficiency virus (HIV-1 replication in lymphoid tissue ex vivo. We found marked differences in the outcomes of such treatment. While flagellin (TLR5 agonist treatment enhanced replication of CC chemokine receptor 5 (CCR 5-tropic and CXC chemokine receptor 4 (CXCR4-tropic HIV-1, treatment with oligodeoxynucleotide (ODN M362 (TLR9 agonist suppressed both viral variants. The differential effects of these TLR ligands on HIV-1 replication correlated with changes in production of CC chemokines CCL3, CCL4, CCL5, and of CXC chemokines CXCL10, and CXCL12 in the ligand-treated HIV-1-infected tissues. The nature and/or magnitude of these changes were dependent on the ligand as well as on the HIV-1 viral strain. Moreover, the tested ligands differed in their ability to induce cellular activation as evaluated by the expression of the cluster of differentiation markers (CD 25, CD38, CD39, CD69, CD154, and human leukocyte antigen D related (HLA-DR as well as of a cell proliferation marker, Ki67, and of CCR5. No significant effect of the ligand treatment was observed on apoptosis and cell death/loss in the treated lymphoid tissue ex vivo. Our results suggest that binding of microbial ligands to TLRs is one of the mechanisms that mediate interactions between coinfected microbes and HIV-1 in human tissues. Thus, the engagement of appropriate TLRs by microbial molecules or their mimetic might become a new strategy for HIV therapy or prevention.

  1. Total glucosides of paeony attenuated functional maturation of dendritic cells via blocking TLR4/5 signaling in vivo.

    Science.gov (United States)

    Zhou, Zhou; Lin, Jinpiao; Huo, Rongfen; Huang, Wenkang; Zhang, Jian; Wang, Li; Sun, Yue; Shen, Baihua; Li, Ningli

    2012-11-01

    It is well known that dendritic cells (DCs) play a critical role in the initiation and development of an immune response. Inhibitory effect on DC maturation alters immune-mediated inflammatory reaction in vivo. Total glucosides of paeony (TGP) are active compounds extracted from the roots of Paeonia lactiflora and have been widely used to ameliorate inflammation in therapy for autoimmune diseases. However, whether TGP act on DC maturation remains unknown. In this study, we investigated the effect of TGP on DC maturation in ovalbumin (OVA) immunized mice. Ear inflammation was inhibited by TGP (150 mgkg(-1), i.p.×11 days) obviously. The antigen presenting capacity of DC derived from TGP-treated mice was arrested. Meanwhile, OVA specific T cell proliferation was inhibited. In addition, we found that maturation of DCs was decreased by TGP treatment. Furthermore, OVA specific T cell proliferation was rescued by the adoptive transfer of mature DCs (mDCs) into TGP treated OVA-challenged mice. The research on the mechanism showed that TGP significantly inhibited activation of TLR4/5 singling. All these results demonstrated that TGP inhibited DC maturation and function by selectively blocking TLR4/5 activation in vivo, which in turn leads to reduce immune-mediated inflammation in vivo, adding a novel mechanism and therapeutic target of TGP for inflammatory and autoimmune disease treatment. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Development of a novel severe triple allergen asthma model in mice which is resistant to dexamethasone and partially resistant to TLR7 and TLR9 agonist treatment.

    Directory of Open Access Journals (Sweden)

    Matthias J Duechs

    Full Text Available Severe asthma is characterised by persistent inflammation, hyperreactivity and remodeling of the airways. No efficient treatment is available, this is particularly the case for steroid resistant phenotypes. Our aim therefore was to develop a preclinical model showing characteristics of severe human asthma including steroid insensitivity. Mice were first sensitized with ovalbumin, extracts of cockroach or house dust mite followed by a challenge period of seven weeks. Further to this, an additional group of mice was sensitized with all three allergens and then challenged with allergen alternating weekly between allergens. All three allergens applied separately to the mice induced comparably strong Th2-type airway inflammation, airway hyperreactivity and airway remodeling, which was characterised by fibrosis and increased smooth muscle thickness. In contrast, application of all three allergens together resulted in a greater Th2 response and increased airway hyperreactivity and a stronger albeit not significant remodeling phenotype compared to using HDM or CRA. In this triple allergen model dexamethasone application, during the last 4 weeks of challenge, showed no suppressive effects on any of these parameters in this model. In contrast, both TLR7 agonist resiquimod and TLR9 agonist CpG-ODN reduced allergen-specific IgE, eosinophils, and collagen I in the lungs. The TLR9 agonist also reduced IL-4 and IL-5 whilst increasing IFN-γ and strongly IL-10 levels in the lungs, effects not seen with the TLR7 agonist. However, neither TLR agonist had any effect on airway hyperreactivity and airway smooth muscle mass. In conclusion we have developed a severe asthma model, which is steroid resistant and only partially sensitive to TLR7 and TLR9 agonist treatment. This model may be particular useful to test new potential therapeutics aiming at treating steroid resistant asthma in humans and investigating the underlying mechanisms responsible for steroid

  3. TLR4 Expression Is Associated with Left Ventricular Dysfunction in Patients Undergoing Coronary Artery Bypass Surgery.

    Directory of Open Access Journals (Sweden)

    Orna Avlas

    Full Text Available Toll-like receptor 4 (TLR4 is an innate immune receptor expressed in immune cells and the heart. Activation of the immune system following myocardial ischemia causes the release of proinflammatory mediators that may negatively influence heart function.The aim of this study is to determine whether TLR4 is activated in peripheral monocytes and heart tissue taken from patients with varying degrees of myocardial dysfunction caused by coronary artery diseases and scheduled for coronary artery bypass graft (CABG surgery before 12 months following operation.Patients (n = 44 undergoing CABG surgery having left ventricular ejection fraction ≤ 45% ('reduced EF', n = 20 were compared to patients with preserved EF >45% ('preserved EF' group, n = 24. 'Reduced EF' patients exhibited increased TLR4 expression in monocytes (2.78±0.49 vs. 1.76±0.07 rMFI, p = 0.03. Plasma levels of C-reactive protein, microRNA miR-320a, brain natriuretic peptide (pro BNP and NADPH oxidase (NOX4 were also significantly different between the 'preserved EF' and 'reduced EF'groups. Elevated TLR4 gene expression levels in the right auricle correlated with those of EF (p<0.008, NOX4 (p<0.008 and miR320, (p<0.04. In contrast, no differences were observed in peripheral monocyte TLR2 expression. After CABG surgery, monocyte TLR4 expression decreased in all patients, reaching statistical significance in the 'reduced EF' group.TLR4 is activated in peripheral monocytes and heart tissue obtained from patients with ischemic heart disease and reduced left ventricular function. Coronary revascularization decreases TLR4 expression. We therefore propose that TLR4 plays a pathogenic role and may serve as an additional marker of ischemic myocardial dysfunction.

  4. Meat and fiber intake and interaction with pattern recognition receptors (TLR1, TLR2, TLR4, and TLR10) in relation to colorectal cancer in a Danish prospective, case-cohort study

    DEFF Research Database (Denmark)

    Kopp, Tine Iskov; Vogel, Ulla; Tjonneland, Anne

    2018-01-01

    Background: Meat and dietary fiber are associated with increased and decreased risk of colorectal cancer (CRC), respectively. Toll-like receptors (TLRs) regulate the intestinal immune response in a complex interplay between the mucosal epithelium and the microbiota and may therefore be important...... modulators of diet-induced CRC together with other inflammatory mediators. Objective: Our aim was to investigate the association between functional TLR polymorphisms and risk of CRC and the interaction with dietary factors. Additionally, interactions with previously studied polymorphisms in IL10, IL1B, PTGS2......, and NFKB1 were assessed in order to examine possible biological pathways in meat-induced CRC. Design: A nested case-cohort study of 897 CRC cases and 1689 randomly selected participants from the Danish prospective "Diet, Cancer and Health" study encompassing 57,053 persons was performed using Cox...

  5. DMPD: TLR3 in antiviral immunity: key player or bystander? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16027039 TLR3 in antiviral immunity: key player or bystander? Schroder M, Bowie AG.... Trends Immunol. 2005 Sep;26(9):462-8. (.png) (.svg) (.html) (.csml) Show TLR3 in antiviral immunity: key player... or bystander? PubmedID 16027039 Title TLR3 in antiviral immunity: key player or bystander? Authors Schr... File (.png) SVG File (.svg) HTML File (.html) CSML File (.csml) Open .csml file with CIOPlayer Open .csml file with CIOPlayer... - ※CIO Playerのご利用上の注意 Open .csml file with CIO Open .csml file with CIO - ※CIOのご利用上の注意 ...

  6. Glaucocalyxin B Alleviates Lipopolysaccharide-Induced Parkinson’s Disease by Inhibiting TLR/NF-κB and Activating Nrf2/HO-1 Pathway

    Directory of Open Access Journals (Sweden)

    Wei Xu

    2017-12-01

    Full Text Available Background/Aims: Parkinson’s disease (PD is a common neurodegenerative disease in the old population, characterized by dopaminergic neuron loss, inflammation and oxidative stress injury in the substantia nigra. Glaucocalyxin B (GLB, an ent-kauranoid diterpenoid isolated from Rabdosia japonica, has anti-inflammation and anti-tumor effects. However, its effects on PD remain unclear. Methods: PD was introduced in rats via injection of lipopolysaccharide (LPS into cerebral corpus striatum, and GLB was given intracerebroventricularly to these rats. Their walking, climbing and sensory states were detected by Stepping, Whisker and Cylinder Tests. The expression of tyrosine hydroxylase (TH, glial fibrillary acidic protein (GFAP, CD11b and ionized calcium binding adaptor molecule (IBA-1 were detected by immunohischemical staining. The levels of a series of inflammatory factors, oxidative stress-related factors and apoptosis-related factors were measured by real-time PCR, immunoblotting and ELISA. In addition, Toll-like receptor (TLR/nuclear factor kappa B (NF-κB and nuclear factor erythroid 2-related factor 2 (Nrf2/heme oxygenase (HO-1 pathways were investigated to illustrate the underlying mechanism. In vitro, microglial cells exposed to LPS were treated with GLB. Results: The injection of LPS caused walking, climbing and sensory disturbances in rats, induced inflammation, oxidative stress response and apoptosis, and activated TLR/NF-κB and Nrf2/ HO-1 pathways in the cerebral tissue. GLB administration attenuated LPS-induced alterations. The TLR/NF-κB pathway was deactivated and Nrf2/HO-1 was activated after application of GLB. In vitro, cytotoxic effects induced by the conditioned medium derived from microglial cells exposed to LPS in PC12 cells were attenuated by GLB. Conclusion: GLB suppresses LPS-induced PD symptoms by modification of TLR/NF-κB and Nrf2/HO-1 pathways in vivo and in vitro.

  7. Polymorphisms at Locus 4p14 of Toll-Like Receptors TLR-1 and TLR-10 Confer Susceptibility to Gastric Carcinoma in Helicobacter pylori Infection.

    Directory of Open Access Journals (Sweden)

    M Ravishankar Ram

    Full Text Available Helicobacter pylori (H. pylori -induced gastric inflammation impacts the functions of leptin- and ghrelin-producing cells in the gastroduodenum. Inflammation resulting from H. pylori sensing via Toll-like receptors (TLRs and the associated downstream signaling largely remain ambiguous. Here, we investigated the role of gut hormones, pro-inflammatory cytokines and single nucleotide polymorphisms (SNPs associated with TLR 4p14 in H. pylori disease in 30 subjects with non-ulcer dyspepsia (NUD, 40 with peptic ulcer disease (PUD and 15 with gastric cancer (GC subjects positive and negative for H. pylori infection. The level of pro-inflammatory cytokines was directly proportional to the severity of gastritis, and disease status influenced the levels of gut hormones and pro-inflammatory cytokines. TLR-1 SNPs rs4833095 and TLR-10 SNPs rs10004195 and were directly associated with H. pylori disease, and were up-regulated in the presence of H. pylori in a genotype-independent manner. We concluded that TLR-1 rs4833095 and TLR10 rs10004195 confer susceptibility to development of gastroduodenal disease, especially GC in H.pylori disease.

  8. Role of innate immune receptors TLR2 and TLR4 as mediators of the inflammatory reaction in human visceral adipose tissue.

    Science.gov (United States)

    Fusaru, Ana Marina; Stănciulescu, Camelia Elena; Surlin, V; Taisescu, C; Bold, Adriana; Pop, O T; Baniţă, Ileana Monica; Crăiţoiu, Stefania; Pisoschi, Cătălina Gabriela

    2012-01-01

    White adipose tissue from different locations is characterized by significant differences in the structure of adipocyte "secretoma". Fat accumulation in the central-visceral depots is usually associated with a chronic inflammatory state, which is complicated by the metabolic syndrome. Recently, the adipose tissue was emerged to have an essential role in the innate immunity, adipocytes being considered effector cells due to the presence of the Toll-like receptors (TLRs). In this study, we compared the expression of TNF-α, TLR2 and TLR4 in peripheral-subcutaneous and central-peritoneal adipose depots in three different conditions - lean, obese and obese diabetic - using immunohistochemistry. Our results suggest a correlation between the incidence of the stromal vascular cells and adipocytes TNF-α and TLR4 in the visceral depots in strong correlation with adipose tissue expansion. TLR2 positive cells were seen in the peripheral depots from all groups without any association with fat accumulation. These results focus on the existence of a new pathogenic pathway, the activation of TLR4, for the involvement of visceral adipose tissue in the activation and maintenance of the inflammatory cascade in obesity.

  9. Live Faecalibacterium prausnitzii induces greater TLR2 and TLR2/6 activation than the dead bacterium in an apical anaerobic co-culture system.

    Science.gov (United States)

    Maier, Eva; Anderson, Rachel C; Altermann, Eric; Roy, Nicole C

    2018-02-01

    Inappropriate activation of intestinal innate immune receptors, such as toll-like receptors (TLRs), by pathogenic bacteria is linked to chronic inflammation. In contrast, a "tonic" level of TLR activation by commensal bacteria is required for intestinal homeostasis. A technical challenge when studying this activation in vitro is the co-culturing of oxygen-requiring mammalian cells with obligate anaerobic commensal bacteria. To overcome this, we used a novel apical anaerobic co-culture system to successfully adapt a TLR activation assay to be conducted in conditions optimised for both cell types. Live Faecalibacterium prausnitzii, an abundant obligate anaerobe of the colonic microbiota, induced higher TLR2 and TLR2/6 activation than the dead bacterium. This enhanced TLR induction by live F. prausnitzii, which until now has not previously been described, may contribute to maintenance of gastrointestinal homeostasis. This highlights the importance of using physiologically relevant co-culture systems to decipher the mechanisms of action of live obligate anaerobes. © 2017 John Wiley & Sons Ltd.

  10. Role of TLR4 gene polymorphisms in the colorectal cancer risk ...

    African Journals Online (AJOL)

    Role of TLR4 gene polymorphisms in the colorectal cancer risk modulation in ethnic Kashmiri population – A case–control study. Saniya Nissar, Aga Syed Sameer, Roohi Rasool, Qurteeba Qadri, Nissar A. Chowdri, Fouzia Rashid ...

  11. Ebola Virus Glycoprotein Induces an Innate Immune Response In vivo via TLR4

    Directory of Open Access Journals (Sweden)

    Chih-Yun Lai

    2017-08-01

    Full Text Available Ebola virus (EBOV, a member of the Filoviridae family, causes the most severe form of viral hemorrhagic fever. Although no FDA licensed vaccine or treatment against Ebola virus disease (EVD is currently available, Ebola virus glycoprotein (GP is the major antigen used in all candidate Ebola vaccines. Recent reports of protection as quickly as within 6 days of administration of the rVSV-based vaccine expressing EBOV GP before robust humoral responses were generated suggests that the innate immune responses elicited early after vaccination may contribute to the protection. However, the innate immune responses induced by EBOV GP in the absence of viral vectors or adjuvants have not been fully characterized in vivo. Our recent studies demonstrated that immunization with highly purified recombinant GP in the absence of adjuvants induced a robust IgG response and partial protection against EBOV infection suggesting that GP alone can induce protective immunity. In this study we investigated the early immune response to purified EBOV GP alone in vitro and in vivo. We show that GP was efficiently internalized by antigen presenting cells and subsequently induced production of key inflammatory cytokines. In vivo, immunization of mice with EBOV GP triggered the production of key Th1 and Th2 innate immune cytokines and chemokines, which directly governed the recruitment of CD11b+ macrophages and CD11c+ dendritic cells to the draining lymph nodes (DLNs. Pre-treatment of mice with a TLR4 antagonist inhibited GP-induced cytokine production and recruitment of immune cells to the DLN. EBOV GP also upregulated the expression of costimulatory molecules in bone marrow derived macrophages suggesting its ability to enhance APC stimulatory capacity, which is critical for the induction of effective antigen-specific adaptive immunity. Collectively, these results provide the first in vivo evidence that early innate immune responses to EBOV GP are mediated via the TLR4

  12. Sex-specific effects of TLR9 promoter variants on spontaneous clearance of HCV infection.

    Science.gov (United States)

    Fischer, Janett; Weber, Alexander N R; Böhm, Stephan; Dickhöfer, Sabine; El Maadidi, Souhayla; Deichsel, Danilo; Knop, Viola; Klinker, Hartwig; Möller, Bernd; Rasenack, Jens; Wang, Lisa; Sharma, Manu; Hinrichsen, Holger; Spengler, Ulrich; Buggisch, Peter; Sarrazin, Christoph; Pawlita, Michael; Waterboer, Tim; Wiese, Manfred; Probst-Müller, Elsbeth; Malinverni, Raffaele; Bochud, Pierre-Yves; Gardiner, Clair; O'Farrelly, Cliona; Berg, Thomas

    2017-10-01

    As pathogen sensors, Toll-like receptors (TLR) play a role in the first defence line during HCV infection. However, the impact of the DNA sensor TLR9 on the natural course of HCV infection is unknown. To address this, TLR9 promoter polymorphisms (single nucleotide polymorphisms (SNPs)) rs187084 and rs5743836 were investigated for their effect on disease progression. Therefore, the TLR9 SNPs and the interferon lambda 4 ( IFNL4 ) rs12979860 were genotyped in chronically HCV type 1 infected (n=333), in patients who spontaneously cleared the infection (n=161), in the Swiss HCV cohort (n=1057) and the well-characterised German (n=305) and Irish (n=198) 'anti-D' cohorts. Functional analyses were done with promoter reporter constructs of human TLR9 in B cells and assessing TLR9 mRNA levels in whole blood of healthy volunteers. The TLR9 rs187084 C allele was associated with spontaneous virus clearance in women of the study cohort (OR=2.15 (95% CI 1.18 to 3.90) p=0.012), of the Swiss HCV cohort (OR=2.06 (95% CI 1.02 to 4.18) p=0.044) and in both 'anti-D' cohorts (German: OR=2.01 (95% CI 1.14 to 3.55) p=0.016; Irish: OR=1.93 (95% CI 1.10 to 3.68) p=0.047). Multivariate analysis in the combined study and Swiss HCV cohorts supported the results (OR=1.99 (95% CI 1.30 to 3.05) p=0.002). Functional analyses revealed higher transcriptional activities for both TLR9 variants and an association of the C allele of rs5743836 with allele-specific TLR9 mRNA regulation by oestrogens in women. TLR9 promoter SNPs are associated with the natural course of HCV infection and show higher transcriptional activities. Our results imply the DNA sensor TLR9 in natural immunity against the RNA virus, HCV. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  13. Lipid raft localization of TLR2 and its co-receptors is independent of membrane lipid composition

    Directory of Open Access Journals (Sweden)

    Christine Hellwing

    2018-01-01

    Full Text Available Background Toll like receptors (TLRs are an important and evolutionary conserved class of pattern recognition receptors associated with innate immunity. The recognition of Gram-positive cell wall constituents strongly depends on TLR2. In order to be functional, TLR2 predominantly forms a heterodimer with TLR1 or TLR6 within specialized membrane microdomains, the lipid rafts. The membrane lipid composition and the physicochemical properties of lipid rafts are subject to modification by exogenous fatty acids. Previous investigations of our group provide evidence that macrophage enrichment with polyunsaturated fatty acids (PUFA induces a reordering of lipid rafts and non-rafts based on the incorporation of supplemented PUFA as well as their elongation and desaturation products. Methods In the present study we investigated potential constraining effects of membrane microdomain reorganization on the clustering of TLR2 with its co-receptors TLR1 and TLR6 within lipid rafts. To this end, RAW264.7 macrophages were supplemented with either docosahexaenoic acid (DHA or arachidonic acid (AA and analyzed for receptor expression and microdomain localization in context of TLR stimulation. Results and Conclusions Our analyses showed that receptor levels and microdomain localization were unchanged by PUFA supplementation. The TLR2 pathway, in contrast to the TLR4 signaling cascade, is not affected by exogenous PUFA at the membrane level.

  14. The role of TLR2 and bacterial lipoprotein in enhancing airway inflammation and immunity

    Directory of Open Access Journals (Sweden)

    Amit A Lugade

    2011-04-01

    Full Text Available Non-typeable Haemophilus influenzae (NTHI colonizes the lower respiratory tract of patients with chronic obstructive pulmonary disease (COPD and also causes exacerbations of the disease. The 16-kDa lipoprotein P6 has been widely studied as a potential vaccine antigen due to its highly conserved expression amongst NTHI strains. Although P6 is known to induce potent inflammatory responses, its role in the pathogenesis of NTHI infection in vivo has not been examined. Additionally, the presence of an amino-terminal lipid motif on P6 serves to activate host TLR2 signaling. The role of host Toll-like receptor 2 (TLR2 and NTHI expression of the lipoprotein P6 on the induction of airway inflammation and generation of adaptive immune responses following chronic NTHI stimulation was evaluated with TLR2-deficient mice and a P6-deficient NTHI strain. Absence of either host TLR2 or bacterial P6 resulted in diminished levels of immune cell infiltration within lungs of mice exposed to NTHI. Pro-inflammatory cytokine secretion was also reduced in lungs that did not express TLR2 or were exposed to NTHI devoid of P6. Induction of specific antibodies to P6 was severely limited in TLR2-deficient mice. Although mice exposed to the P6-deficient NTHI strain were capable of generating antibodies to other surface antigens of NTHI, these levels were lower compared to those observed in mice exposed to P6-expressing NTHI. Therefore, cognate interaction between host TLR2 and bacterial P6 serves to enhance lung inflammation and elicit robust adaptive immune responses during NTHI exposure. Strategies to limit NTHI inflammation while simultaneously promoting robust immune responses may benefit from targeting the TLR2:P6 signaling axis.

  15. LPS Promotes Vascular Smooth Muscle Cells Proliferation Through the TLR4/Rac1/Akt Signalling Pathway

    Directory of Open Access Journals (Sweden)

    Qianran Yin

    2017-12-01

    Full Text Available Background/Aims: Lipopolysaccharide (LPS is a potent activator of vascular smooth muscle cells (VSMCs proliferation, but the underlying mechanism remains unknown. In this study, we knocked down Toll-like receptor 4 (TLR4 and Ras-related C3 botulinum toxin substrate 1 (Rac1 expression using small interfering RNA (siRNA in order to investigate the effects and possible mechanisms of LPS-induced VSMCs proliferation. Methods: VSMCs proliferation was monitored by 5-ethynyl-2’-deoxyuridine staining, and Rac1 activity was measured via Glutathione S-transferase pull-down assay. mRNAs encoding proliferating cell nuclear antigen (PCNA, smooth muscle 22α (SM22α, myosin heavy chain (MYH and transient receptor potential channel 1 (TRPC1 were detected by qRT-PCR. The expression of total Akt, p-Akt (308, p-Akt (473, SM22α, MYH and TRPC1 protein was analysed by Western blot. Results: Treatment with TLR4 siRNA (siTLR4 or Rac1 siRNA (siRac1 significantly decreased LPS-induced VSMCs proliferation. Moreover, LPS-induced activation of Rac1 through TLR4 was observed. Western blot analysis revealed that transfection with siTLR4 or siRac1 inhibited LPS-induced Akt phosphorylation. We discovered that LPS stimulated VSMCs proliferation via phenotypic modulation and that this effect was partially inhibited by pre-treatment with siTLR4 or siRac1. Further, TLR4 and Rac1 are involved in LPS-induced activation of TRPC1. Conclusion: This study suggests that LPS exerts an effect on VSMCs proliferation and that the TLR4/Rac1/Akt signalling pathway mediates this effect.

  16. Toll like receptors TLR1/2, TLR6 and MUC5B as binding interaction partners with cytostatic proline rich polypeptide 1 in human chondrosarcoma.

    Science.gov (United States)

    Galoian, Karina; Abrahamyan, Silva; Chailyan, Gor; Qureshi, Amir; Patel, Parthik; Metser, Gil; Moran, Alexandra; Sahakyan, Inesa; Tumasyan, Narine; Lee, Albert; Davtyan, Tigran; Chailyan, Samvel; Galoyan, Armen

    2018-01-01

    Metastatic chondrosarcoma is a bone malignancy not responsive to conventional therapies; new approaches and therapies are urgently needed. We have previously reported that mTORC1 inhibitor, antitumorigenic cytostatic proline rich polypeptide 1 (PRP-1), galarmin caused a significant upregulation of tumor suppressors including TET1/2 and SOCS3 (known to be involved in inflammatory processes), downregulation of oncoproteins and embryonic stem cell marker miR-302C and its targets Nanog, c-Myc and Bmi-1 in human chondrosarcoma. To understand better the mechanism of PRP-1 action it was very important to identify the receptor it binds to. Nuclear pathway receptor and GPCR assays indicated that PRP-1 receptors are not G protein coupled, neither do they belong to family of nuclear or orphan receptors. In the present study, we have demonstrated that PRP-1 binding interacting partners belong to innate immunity pattern recognition toll like receptors TLR1/2 and TLR6 and gel forming secreted mucin MUC5B. MUC5B was identified as PRP-1 receptor in human chondrosarcoma JJ012 cell line using Ligand-receptor capture technology. Toll like receptors TLR1/2 and TLR6 were identified as binding interaction partners with PRP-1 by western blot analysis in human chondrosarcoma JJ012 cell line lysates. Immunocytochemistry experiments confirmed the finding and indicated the localization of PRP-1 receptors in the tumor nucleus predominantly. TLR1/2, TLR6 and MUC5B were downregulated in human chondrosarcoma and upregulated in dose-response manner upon PRP-1 treatment. Experimental data indicated that in this cellular context the mentioned receptors had tumor suppressive function.

  17. Expression of TLR-2, TLR-4, NOD2 and pNF-kappaB in a neonatal rat model of necrotizing enterocolitis.

    Directory of Open Access Journals (Sweden)

    Aurelie Le Mandat Schultz

    Full Text Available BACKGROUND: The etiology of necrotizing enterocolitis (NEC results from a combination of several risk factors that act synergistically and occurs in the same circumstances as those which lead to innate immunity activation. Pattern recognition molecules could be an important player in the initiation of an exaggerated inflammatory response leading to intestinal injury in NEC. METHODOLOGY/PRINCIPAL FINDINGS: We specifically evaluated intestinal epithelial cell (IEC expression of Toll-like receptor 2 (TLR-2, TLR-4, NOD2 and phosphorylated NF-kappaB (pNF-kappaB after mucosal injury in a rat model of NEC induced by prematurity, systemic hypoxia, and a rich protein formula. In the control group (group 1, neonatal rats were full-term and breast-fed; in the experimental groups, rat pups were preterm at day 21 of gestation and rat-milk fed (group 2 or hand-gavaged with a protein rich formula after a hypoxia-reoxygenation procedure (group 3. Morphological mucosal changes in the small bowel were scored on hematoxylin- and eosin-stained sections. Immunohistochemistry was performed on frozen tissue sections using anti TLR-2 and active pNF-kappaB p65 antibodies. Real-time RT-PCR was performed to assess mRNA expression of NOD2, TLR-2 and TLR-4. Proliferation and apoptosis were studied in paraffin sections using anti Ki-67 and caspase-3 antibodies, respectively. The combination of immaturity, protein rich formula and a hypoxia-reoxygenation procedure induces pathological mucosal damage consistent with NEC. There was an overexpression of TLR-2, and pNF-kappaB in IECs that was correlated with the severity of mucosal damage, together with an increase of apoptotic IECs and markedly impaired proliferation. In addition, these immunological alterations appeared before severe mucosal damage. TLR-2 mRNA were also increased in NEC together with TLR-4 mRNA using real-time RT-PCR whereas NOD2 expression was unchanged. CONCLUSIONS/SIGNIFICANCE: These results show that this

  18. Mutations in the TLR3 signaling pathway and beyond in adult patients with herpes simplex encephalitis.

    Science.gov (United States)

    Mørk, N; Kofod-Olsen, E; Sørensen, K B; Bach, E; Ørntoft, T F; Østergaard, L; Paludan, S R; Christiansen, M; Mogensen, T H

    2015-12-01

    Herpes simplex encephalitis (HSE) in children has previously been linked to defects in type I interferon production downstream of Toll-like receptor (TLR)3. In the present study, we used whole-exome sequencing to investigate the genetic profile of 16 adult patients with a history of HSE. We identified novel mutations in IRF3, TYK2 and MAVS, molecules involved in generating innate antiviral immune responses, which have not previously been associated with HSE. Moreover, data revealed mutations in TLR3, TRIF, TBK1 and STAT1 known to be associated with HSE in children but not previously described in adults. All discovered mutations were heterozygous missense mutations, the majority of which were associated with significantly decreased antiviral responses to HSV-1 infection and/or the TLR3 agonist poly(I:C) in patient peripheral blood mononuclear cells compared with controls. Altogether, this study demonstrates novel mutations in the TLR3 signaling pathway in molecules previously identified in children, suggesting that impaired innate immunity to HSV-1 may also increase susceptibility to HSE in adults. Importantly, the identification of mutations in innate signaling molecules not directly involved in TLR3 signaling suggests the existence of innate immunodeficiencies predisposing to HSE beyond the TLR3 pathway.

  19. TLR-dependent human mucosal epithelial cell responses to microbial pathogens.

    Directory of Open Access Journals (Sweden)

    Paola eMassari

    2014-08-01

    Full Text Available AbstractToll-Like Receptor (TLR signaling represents one of the best studied pathways to implement defense mechanisms against invading microbes in humans as well as in animals. TLRs respond to specific microbial ligands and to danger signals produced by the host during infection, and initiate downstream cascades that activate both innate and adaptive immunity. TLRs are expressed by professional immune cells and by the large majority of non-hematopoietic cells, including epithelial cells. In epithelial tissues, TLR functions are particularly important because these sites are constantly exposed to microorganisms, due to their location at the host interface with the environment. While at these sites, specific defense mechanisms and inflammatory responses are initiated via TLR signaling against pathogens, suppression or lack of TLR activation is also observed in response to the commensal microbiota. The mechanisms by which TLR signaling is regulated in mucosal epithelial cells include differential expression and levels of TLRs (and their signaling partners, their cellular localization and positioning within the tissue in a fashion that favors responses to pathogens while dampening responses to commensals and maintaining tissue homeostasis in physiologic conditions. In this review, the expression and activation of TLRs in mucosal epithelial cells of several sites of the human body are examined. Specifically, the oral cavity, the ear canal and eye, the airways, the gut and the reproductive tract are discussed, along with how site-specific host defense mechanisms are implemented via TLR signaling.

  20. Toll like receptor 4 (TLR4) mediates the stimulating activities of chitosan oligosaccharide on macrophages.

    Science.gov (United States)

    Zhang, Pei; Liu, Weizhi; Peng, Yanfei; Han, Baoqin; Yang, Yan

    2014-11-01

    The in vivo and in vitro immunostimulating properties of chitosan oligosaccharide (COS) prepared by enzymatic hydrolysis of chitosan and the mechanisms mediating the effects were investigated. Our data showed that the highly active chitosanase isolated could hydrolyze chitosan to the polymerization degree of 3-8. The resulting COS was an efficient immunostimulator. COS markedly enhanced the proliferation and neutral red phagocytosis by RAW 264.7 macrophages. The production of nitric oxide (NO) and tumor necrosis factor alpha (TNF-α) by macrophages was significantly increased after incubation with COS. Oral administration of COS in mice could increase spleen index and serum immunoglobin G (IgG) contents. COS was labeled with FITC to study the pinocytosis by macrophages. Results showed that FITC-COS was phagocyted by macrophages and anti-murine TLR4 antibody completely blocked FITC-COS pinocytosis. RT-PCR indicated that COS treatment of macrophages significantly increased TLR4 and inducible nitric oxide synthase (iNOS) mRNA levels. When cells were pretreated with anti-murine TLR4 antibody, the effect of COS on TLR4 and iNOS mRNA induction was decreased. COS-induced NO secretion by macrophages was also markedly decreased by anti-murine TLR4 antibody pretreatment. In conclusion, the present study revealed that COS possesses potent immune-stimulating properties by activating TLR4 on macrophages. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. PMA Induces Vaccine Adjuvant Activity by the Modulation of TLR Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Dool-Ri Oh

    2014-01-01

    Full Text Available Toll-like receptor (TLR ligands are being developed for use as vaccine adjuvants and as immunomodulators because of their ability to stimulate innate and adaptive immune responses. Flagellin, a TLR5 ligand, was reported to show potent mucosal vaccine adjuvant activity. To identify ligands that potentiate the adjuvant activity of flagellin, we screened a plant library using HEK293T cells transiently cotransfected with phTLR5 and pNF-κB-SEAP plasmids. The 90% EtOH extract from Croton tiglium showed significant NF-κB transactivation in a TLR5-independent manner along with the increase of a flagellin activity. We have studied to characterize an active component from Croton tiglium and to elucidate the action mechanisms. Phorbol 12-myristate 13-acetate (PMA was isolated as an active component of Croton tiglium by activity-guided fractionation, column chromatography, HPLC, NMR, and MS. PMA at a range of nM induced PKC-dependent NF-κB activation and IL-8 production in both TLR5− and TLR5+ assay systems. In in vivo mouse vaccination model, PMA induced antigen-specific IgG and IgA antibody responses and increased IL-12 production corresponding to T cell responses in spleen lymphocytes. These results suggest that PMA would serve as an efficacious mucosal vaccine adjuvant.

  2. Treatment of autoimmune inflammation by a TLR7 ligand regulating the innate immune system.

    Directory of Open Access Journals (Sweden)

    Tomoko Hayashi

    Full Text Available The Toll-like receptors (TLR have been advocated as attractive therapeutic targets because TLR signaling plays dual roles in initiating adaptive immune responses and perpetuating inflammation. Paradoxically, repeated stimulation of bone marrow mononuclear cells with a synthetic TLR7 ligand 9-benzyl-8-hydroxy-2-(2-methoxyethoxy adenine (called 1V136 leads to subsequent TLR hyporesponsiveness. Further studies on the mechanism of action of this pharmacologic agent demonstrated that the TLR7 ligand treatment depressed dendritic cell activation, but did not directly affect T cell function. To verify this mechanism, we utilized experimental allergic encephalitis (EAE as an in vivo T cell dependent autoimmune model. Drug treated SJL/J mice immunized with proteolipid protein (PLP(139-151 peptide had attenuated disease severity, reduced accumulation of mononuclear cells in the central nervous system (CNS, and limited demyelination, without any apparent systemic toxicity. Splenic T cells from treated mice produced less cytokines upon antigenic rechallenge. In the spinal cords of 1V136-treated EAE mice, the expression of chemoattractants was also reduced, suggesting innate immune cell hyposensitization in the CNS. Indeed, systemic 1V136 did penetrate the CNS. These experiments indicated that repeated doses of a TLR7 ligand may desensitize dendritic cells in lymphoid organs, leading to diminished T cell responses. This treatment strategy might be a new modality to treat T cell mediated autoimmune diseases.

  3. Significance of TLR4/MyD88 expression in breast cancer

    Science.gov (United States)

    Chen, Xiangjin; Zhao, Feng; Zhang, Huihao; Zhu, Youzhi; Wu, Kunlin; Tan, Guozheng

    2015-01-01

    Objective: To investigate the expression of TLR4/MyD88 in breast cancer, and explore the relationship between their expression and breast cancer tumor growth and invasion. Methods: We examined the protein expression of TLR4 and MyD88 in 60 cases of histologically confirmed breast cancer. The relationship of their protein expressions with clinical features including age at diagnosis, tumor size and stage, lymph node metastasis and distant metastasis were analyzed. Results: The IHC results showed that TLR4 and MyD88 were expressed in 63.3% (38/60) and 58.3% (35/60) of malignant breast tumors respectively. TLR4 expression in breast cancer were significantly higher than in fibroadenoma (n = 4, 20.0%) and adjacent normal tissues (n = 2, 10.0%) (P fibroadenoma (n = 4, 20.0%) and adjacent normal tissue (n = 3, 15.0%) (P fibroadenoma and adjacent normal tissues (P < 0.05). The protein expressions of TLR4 and MyD88 were also significantly associated with poor clinical features (P < 0.05). Conclusion: TLR4 and MyD88 expression might be associated with breast cancer growth and regional and distant metastases. PMID:26261595

  4. Cigarette smoke regulates the expression of TLR4 and IL-8 production by human macrophages

    Directory of Open Access Journals (Sweden)

    Rahman Irfan

    2009-05-01

    Full Text Available Abstract Background Toll-like receptors (TLRs are present on monocytes and alveolar macrophages that form the first line of defense against inhaled particles. The importance of those cells in the pathophysiology of chronic obstructive pulmonary disease (COPD has well been documented. Cigarette smoke contains high concentration of oxidants which can stimulate immune cells to produce reactive oxygen species, cytokines and chemokines. Methods In this study, we evaluated the effects of cigarette smoke medium (CSM on TLR4 expression and interleukin (IL-8 production by human macrophages investigating the involvement of ROS. Results and Discussion TLR4 surface expression was downregulated on short term exposure (1 h of CSM. The downregulation could be explained by internalization of the TLR4 and the upregulation by an increase in TLR4 mRNA. IL-8 mRNA and protein were also increased by CSM. CSM stimulation increased intracellular ROS-production and decreased glutathione (GSH levels. The modulation of TLR4 mRNA and surface receptors expression, IRAK activation, IκB-α degradation, IL-8 mRNA and protein, GSH depletion and ROS production were all prevented by antioxidants such as N-acetyl-L-cysteine (NAC. Conclusion TLR4 may be involved in the pathogenesis of lung emphysema and oxidative stress and seems to be a crucial contributor in lung inflammation.

  5. S100A9 interaction with TLR4 promotes tumor growth.

    Directory of Open Access Journals (Sweden)

    Eva Källberg

    Full Text Available By breeding TRAMP mice with S100A9 knock-out (S100A9(-/- animals and scoring the appearance of palpable tumors we observed a delayed tumor growth in animals devoid of S100A9 expression. CD11b(+ S100A9 expressing cells were not observed in normal prostate tissue from control C57BL/6 mice but were readily detected in TRAMP prostate tumors. Also, S100A9 expression was observed in association with CD68(+ macrophages in biopsies from human prostate tumors. Delayed growth of TRAMP tumors was also observed in mice lacking the S100A9 ligand TLR4. In the EL-4 lymphoma model tumor growth inhibition was observed in S100A9(-/- and TLR4(-/-, but not in RAGE(-/- animals lacking an alternative S100A9 receptor. When expression of immune-regulating genes was analyzed using RT-PCR the only common change observed in mice lacking S100A9 and TLR4 was a down-regulation of TGFβ expression in splenic CD11b(+ cells. Lastly, treatment of mice with a small molecule (ABR-215050 that inhibits S100A9 binding to TLR4 inhibited EL4 tumor growth. Thus, S100A9 and TLR4 appear to be involved in promoting tumor growth in two different tumor models and pharmacological inhibition of S100A9-TLR4 interactions is a novel and promising target for anti-tumor therapies.

  6. The combination of maltose-binding protein and BCG-induced Th1 activation is involved in TLR2/9-mediated upregulation of MyD88-TRAF6 and TLR4-mediated downregulation of TRIF-TRAF3.

    Science.gov (United States)

    Liu, Guomu; Zhai, Xiaoyu; Zhou, Hongyue; Yang, Xiaoyu; Zhang, Nannan; Tai, Guixiang; Ni, Weihua

    2018-03-01

    Our previous study demonstrated that maltose-binding protein (MBP) activated Th1 through the TLR2-mediated MyD88-dependent pathway and the TLR4-mediated TRIF-dependent pathway. The combination of MBP and BCG synergistically induced Th1 activation, and the TLR2/9-mediated MyD88-dependent pathway is involved in this process. To further explore this mechanism, we stimulated purified mouse CD4 + T cells with MBP and BCG in vitro. The results demonstrated that MBP combined with BCG synergistically increased IFN-γ production and TLR2/4/9 expression, suggesting the involvement of TLR2/4/9 in the combination-induced Th1 activation. Next, TLRs 2/4/9 were blocked to analyze the effects of TLRs on Th1 activation. The results demonstrated that MBP induced a low level of Th1 activation by upregulating TLR2-mediated MyD88-TRAF6 and TLR4-mediated TRIF-TRAF3 expression, whereas MBP combined with BCG induced synergistic Th1 activation, which was not only triggered by strong upregulation of TLR2/9-mediated MyD88-TRAF6 expression but also by shifting TLR4-mediated TRIF-TRAF3 into the TRIF-TRAF6 pathway. Moreover, we observed that a TLR4 antibody upregulated MyD88 expression and a TLR9 inhibitor downregulated TRIF expression, indicating that there was cross-talk between TLRs 2/4/9 in MBP combined with BCG-induced Th1 activation. Our findings may expand the knowledge regarding TLR cross-talk involved in regulating the Th1 response. Copyright © 2018 Elsevier Inc. All rights reserved.

  7. TLR3 deficiency renders astrocytes permissive to herpes simplex virus infection and facilitates establishment of CNS infection in mice

    DEFF Research Database (Denmark)

    Reinert, Line; Harder, Louis Andreas; Holm, Christian

    2012-01-01

    Herpes simplex viruses (HSVs) are highly prevalent neurotropic viruses. While they can replicate lytically in cells of the epithelial lineage, causing lesions on mucocutaneous surfaces, HSVs also establish latent infections in neurons, which act as reservoirs of virus for subsequent reactivation......, it is not known what cell type mediates the role of TLR3 in the immunological control of HSV, and it is not known whether TLR3 sensing occurs prior to or after CNS entry. Here, we show that in mice TLR3 provides early control of HSV-2 infection immediately after entry into the CNS by mediating type I IFN...... responses in astrocytes. Tlr3-/- mice were hypersusceptible to HSV-2 infection in the CNS after vaginal inoculation. HSV-2 exhibited broader neurotropism in Tlr3-/- mice than it did in WT mice, with astrocytes being most abundantly infected. Tlr3-/- mice did not exhibit a global defect in innate immune...

  8. Constitutive MHC class I molecules negatively regulate TLR-triggered inflammatory responses via the Fps-SHP-2 pathway.

    Science.gov (United States)

    Xu, Sheng; Liu, Xingguang; Bao, Yan; Zhu, Xuhui; Han, Chaofeng; Zhang, Peng; Zhang, Xuemin; Li, Weihua; Cao, Xuetao

    2012-04-22

    The molecular mechanisms that fine-tune Toll-like receptor (TLR)-triggered innate inflammatory responses remain to be fully elucidated. Major histocompatibility complex (MHC) molecules can mediate reverse signaling and have nonclassical functions. Here we found that constitutively expressed membrane MHC class I molecules attenuated TLR-triggered innate inflammatory responses via reverse signaling, which protected mice from sepsis. The intracellular domain of MHC class I molecules was phosphorylated by the kinase Src after TLR activation, then the tyrosine kinase Fps was recruited via its Src homology 2 domain to phosphorylated MHC class I molecules. This led to enhanced Fps activity and recruitment of the phosphatase SHP-2, which interfered with TLR signaling mediated by the signaling molecule TRAF6. Thus, constitutive MHC class I molecules engage in crosstalk with TLR signaling via the Fps-SHP-2 pathway and control TLR-triggered innate inflammatory responses.

  9. Reversal of Human Papillomavirus-Specific T Cell Immune Suppression through TLR Agonist Treatment of Langerhans Cells Exposed to Human Papillomavirus Type 161

    Science.gov (United States)

    Fahey, Laura M.; Raff, Adam B.; Da Silva, Diane M.; Kast, W. Martin

    2009-01-01

    Human papillomavirus (HPV) type 16 infects the epithelial layer of cervical mucosa and is causally associated with the generation of cervical cancer. Langerhans cells (LC) are the resident antigen-presenting cells at the site of infection and therefore are responsible for initiating an immune response against HPV16. On the contrary, LC exposed to HPV16 do not induce a specific T cell immune response, which leads to the immune evasion of HPV16. Demonstrating that Toll-like receptor 7 (TLR7) and TLR8 are expressed on human LC, we hypothesized that imidazoquinolines would activate LC exposed to HPV16, leading to the induction of an HPV16-specific cell-mediated immune response. Surprisingly both phenotypic and functional hallmarks of activation are not observed when LC are exposed to HPV16 virus-like particles (VLP) and treated with imiquimod (TLR7 agonist). However, we found that LC are activated by 3M-002 (TLR8 agonist) and resiquimod (TLR8/7 agonist). LC exposed to HPV16 VLP and subsequently treated with 3M-002 or resiquimod highly up-regulate surface activation markers, secrete pro-inflammatory cytokines and chemokines, induce CCL21-directed migration, and initiate an HPV16-specific CD8+ T cell response. These data strongly indicate that 3M-002 and resiquimod are promising therapeutics for treatment of HPV-infections and HPV-induced cervical lesions. This is an author-produced version of a manuscript accepted for publication in The Journal of Immunology (The JI). The American Association of Immunologists, Inc. (AAI), publisher of The JI, holds the copyright to this manuscript. This version of the manuscript has not yet been copyedited or subjected to editorial proofreading by The JI; hence, it may differ from the final version published in The JI (online and in print). AAI (The JI) is not liable for errors or omissions in this author-produced version of the manuscript or in any version derived from it by the U.S. National Institutes of Health or any other third

  10. DMPD: Viral immunity: cross-priming with the help of TLR3. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15886091 Viral immunity: cross-priming with the help of TLR3. Salio M, Cerundolo V.... Curr Biol. 2005 May 10;15(9):R336-9. (.png) (.svg) (.html) (.csml) Show Viral immunity: cross-priming with the help... of TLR3. PubmedID 15886091 Title Viral immunity: cross-priming with the help of TLR3. Authors Salio

  11. Modulation of neonatal microbial recognition: TLR-mediated innate immune responses are specifically and differentially modulated by human milk.

    Science.gov (United States)

    LeBouder, Emmanuel; Rey-Nores, Julia E; Raby, Anne-Catherine; Affolter, Michael; Vidal, Karine; Thornton, Catherine A; Labéta, Mario O

    2006-03-15

    The mechanisms controlling innate microbial recognition in the neonatal gut are still to be fully understood. We have sought specific regulatory mechanisms operating in human breast milk relating to TLR-mediated microbial recognition. In this study, we report a specific and differential modulatory effect of early samples (days 1-5) of breast milk on ligand-induced cell stimulation via TLRs. Although a negative modulation was exerted on TLR2 and TLR3-mediated responses, those via TLR4 and TLR5 were enhanced. This effect was observed in human adult and fetal intestinal epithelial cell lines, monocytes, dendritic cells, and PBMC as well as neonatal blood. In the latter case, milk compensated for the low capacity of neonatal plasma to support responses to LPS. Cell stimulation via the IL-1R or TNFR was not modulated by milk. This, together with the differential effect on TLR activation, suggested that the primary effect of milk is exerted upstream of signaling proximal to TLR ligand recognition. The analysis of TLR4-mediated gene expression, used as a model system, showed that milk modulated TLR-related genes differently, including those coding for signal intermediates and regulators. A proteinaceous milk component of > or =80 kDa was found to be responsible for the effect on TLR4. Notably, infant milk formulations did not reproduce the modulatory activity of breast milk. Together, these findings reveal an unrecognized function of human milk, namely, its capacity to influence neonatal microbial recognition by modulating TLR-mediated responses specifically and differentially. This in turn suggests the existence of novel mechanisms regulating TLR activation.

  12. Humanized TLR4/MD-2 mice reveal LPS recognition differentially impacts susceptibility to Yersinia pestis and Salmonella enterica.

    Directory of Open Access Journals (Sweden)

    Adeline M Hajjar

    Full Text Available Although lipopolysaccharide (LPS stimulation through the Toll-like receptor (TLR-4/MD-2 receptor complex activates host defense against Gram-negative bacterial pathogens, how species-specific differences in LPS recognition impact host defense remains undefined. Herein, we establish how temperature dependent shifts in the lipid A of Yersinia pestis LPS that differentially impact recognition by mouse versus human TLR4/MD-2 dictate infection susceptibility. When grown at 37°C, Y. pestis LPS is hypo-acylated and less stimulatory to human compared with murine TLR4/MD-2. By contrast, when grown at reduced temperatures, Y. pestis LPS is more acylated, and stimulates cells equally via human and mouse TLR4/MD-2. To investigate how these temperature dependent shifts in LPS impact infection susceptibility, transgenic mice expressing human rather than mouse TLR4/MD-2 were generated. We found the increased susceptibility to Y. pestis for "humanized" TLR4/MD-2 mice directly paralleled blunted inflammatory cytokine production in response to stimulation with purified LPS. By contrast, for other Gram-negative pathogens with highly acylated lipid A including Salmonella enterica or Escherichia coli, infection susceptibility and the response after stimulation with LPS were indistinguishable between mice expressing human or mouse TLR4/MD-2. Thus, Y. pestis exploits temperature-dependent shifts in LPS acylation to selectively evade recognition by human TLR4/MD-2 uncovered with "humanized" TLR4/MD-2 transgenic mice.

  13. Humanized TLR4/MD-2 mice reveal LPS recognition differentially impacts susceptibility to Yersinia pestis and Salmonella enterica.

    Science.gov (United States)

    Hajjar, Adeline M; Ernst, Robert K; Fortuno, Edgardo S; Brasfield, Alicia S; Yam, Cathy S; Newlon, Lindsay A; Kollmann, Tobias R; Miller, Samuel I; Wilson, Christopher B

    2012-01-01

    Although lipopolysaccharide (LPS) stimulation through the Toll-like receptor (TLR)-4/MD-2 receptor complex activates host defense against Gram-negative bacterial pathogens, how species-specific differences in LPS recognition impact host defense remains undefined. Herein, we establish how temperature dependent shifts in the lipid A of Yersinia pestis LPS that differentially impact recognition by mouse versus human TLR4/MD-2 dictate infection susceptibility. When grown at 37°C, Y. pestis LPS is hypo-acylated and less stimulatory to human compared with murine TLR4/MD-2. By contrast, when grown at reduced temperatures, Y. pestis LPS is more acylated, and stimulates cells equally via human and mouse TLR4/MD-2. To investigate how these temperature dependent shifts in LPS impact infection susceptibility, transgenic mice expressing human rather than mouse TLR4/MD-2 were generated. We found the increased susceptibility to Y. pestis for "humanized" TLR4/MD-2 mice directly paralleled blunted inflammatory cytokine production in response to stimulation with purified LPS. By contrast, for other Gram-negative pathogens with highly acylated lipid A including Salmonella enterica or Escherichia coli, infection susceptibility and the response after stimulation with LPS were indistinguishable between mice expressing human or mouse TLR4/MD-2. Thus, Y. pestis exploits temperature-dependent shifts in LPS acylation to selectively evade recognition by human TLR4/MD-2 uncovered with "humanized" TLR4/MD-2 transgenic mice.

  14. Palmitate induces VSMC apoptosis via toll like receptor (TLR)4/ROS/p53 pathway.

    Science.gov (United States)

    Zhang, Yuanjun; Xia, Guanghao; Zhang, Yaqiong; Liu, Juxiang; Liu, Xiaowei; Li, Weihua; Lv, Yaya; Wei, Suhong; Liu, Jing; Quan, Jinxing

    2017-08-01

    Toll-like receptor 4 (TLR4) has been implicated in vascular inflammation, as well as in the pathogenesis of atherosclerosis and diabetes. Vascular smooth muscle cell (VSMC) apoptosis has been shown to induce plaque vulnerability in atherosclerosis. Previous studies reported that palmitate induced apoptosis in VSMCs; however, the role of TLR4 in palmitate-induced apoptosis in VSMCs has not yet been defined. In this study, we investigated whether or not palmitate-induced apoptosis depended on the activation of the TLR4 pathway. VSMCs were treated with or without palmitate, CRISPR/Cas9z-mediated genome editing methods were used to deplete TLR4 expression, while NADPH oxidase inhibitors were used to inhibit reactive oxygen species (ROS) generation. Cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, ROS was measured using the 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) method, the mRNA and protein expression levels of caspase 3, caspase 9, BCL-2 and p53 were studied by real-time polymerase chain reaction (RT-PCR) and ELISA. Palmitate significantly promotes VSMC apoptosis, ROS generation, and expression of caspase 3, caspase 9 and p53; while NADPH oxidase inhibitor pretreatment markedly attenuated these effects. Moreover, knockdown of TLR4 significantly blocked palmitate-induced ROS generation and VSMC apoptosis accompanied by inhibition of caspase 3, caspase 9, p53 expression and restoration of BCL-2 expression. Our results suggest that palmitate-induced apoptosis depends on the activation of the TLR4/ROS/p53 signaling pathway, and that TLR4 may be a potential therapeutic target for the prevention and treatment of atherosclerosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Gut microbiota is a key modulator of insulin resistance in TLR 2 knockout mice.

    Directory of Open Access Journals (Sweden)

    Andréa M Caricilli

    2011-12-01

    Full Text Available Environmental factors and host genetics interact to control the gut microbiota, which may have a role in the development of obesity and insulin resistance. TLR2-deficient mice, under germ-free conditions, are protected from diet-induced insulin resistance. It is possible that the presence of gut microbiota could reverse the phenotype of an animal, inducing insulin resistance in an animal genetically determined to have increased insulin sensitivity, such as the TLR2 KO mice. In the present study, we investigated the influence of gut microbiota on metabolic parameters, glucose tolerance, insulin sensitivity, and signaling of TLR2-deficient mice. We investigated the gut microbiota (by metagenomics, the metabolic characteristics, and insulin signaling in TLR2 knockout (KO mice in a non-germ free facility. Results showed that the loss of TLR2 in conventionalized mice results in a phenotype reminiscent of metabolic syndrome, characterized by differences in the gut microbiota, with a 3-fold increase in Firmicutes and a slight increase in Bacteroidetes compared with controls. These changes in gut microbiota were accompanied by an increase in LPS absorption, subclinical inflammation, insulin resistance, glucose intolerance, and later, obesity. In addition, this sequence of events was reproduced in WT mice by microbiota transplantation and was also reversed by antibiotics. At the molecular level the mechanism was unique, with activation of TLR4 associated with ER stress and JNK activation, but no activation of the IKKβ-IκB-NFκB pathway. Our data also showed that in TLR2 KO mice there was a reduction in regulatory T cell in visceral fat, suggesting that this modulation may also contribute to the insulin resistance of these animals. Our results emphasize the role of microbiota in the complex network of molecular and cellular interactions that link genotype to phenotype and have potential implications for common human disorders involving obesity, diabetes

  16. The Roles of Bacteria and TLR4 in Rat and Murine Models of Necrotizing Enterocolitis1

    Science.gov (United States)

    Jilling, Tamas; Simon, Dyan; Lu, Jing; Meng, Fan Jing; Li, Dan; Schy, Robert; Thomson, Richard B.; Soliman, Antoine; Arditi, Moshe; Caplan, Michael S.

    2009-01-01

    Bacteria are thought to contribute to the pathogenesis of necrotizing enterocolitis (NEC), but it is unknown whether their interaction with the epithelium can participate in the initiation of mucosal injury or they can act only following translocation across a damaged intestinal barrier. Our aims were to determine whether bacteria and intestinal epithelial TLR4 play roles in a well-established neonatal rat model and a novel neonatal murine model of NEC. Neonatal rats, C57BL/6J, C3HeB/FeJ (TLR4 wild type), and C3H/HeJ (TLR4 mutant) mice were delivered by Cesarean section and were subjected to formula feeding and cold asphyxia stress or were delivered naturally and were mother-fed. NEC incidence was evaluated by histological scoring, and gene expression was quantified using quantitative real-time PCR from cDNA generated from intestinal total RNA or from RNA obtained by laser capture microdissection. Spontaneous feeding catheter colonization or supplementation of cultured bacterial isolates to formula increased the incidence of experimental NEC. During the first 72 h of life, i.e., the time frame of NEC development in this model, intestinal TLR4 mRNA gradually decreases in mother-fed but increases in formula feeding and cold asphyxia stress, correlating with induced inducible NO synthase. TLR4, inducible NO synthase, and inflammatory cytokine induction occurred in the intestinal epithelium but not in the submucosa. NEC incidence was diminished in C3H/HeJ mice, compared with C3HeB/FeJ mice. In summary, bacteria and TLR4 play significant roles in experimental NEC, likely via an interaction of intraluminal bacteria and aberrantly overexpressed TLR4 in enterocytes. PMID:16920968

  17. Characterization of TLR-induced inflammatory responses in COPD and control lung tissue explants

    Directory of Open Access Journals (Sweden)

    Pomerenke A

    2016-09-01

    Full Text Available Anna Pomerenke,1 Simon R Lea,1 Sarah Herrick,2 Mark A Lindsay,3 Dave Singh1 1Centre for Respiratory Medicine and Allergy, Institute of Inflammation and Repair, Manchester Academic Health Science Centre, The University of Manchester and University Hospital of South Manchester, NHS Foundation Trust, 2Institute of Inflammation and Repair, Manchester Academic Health Science Centre, University of Manchester, Manchester, 3Department of Pharmacy and Pharmacology, University of Bath, Bath, UK Purpose: Viruses are a common cause of exacerbations in chronic obstructive pulmonary disease (COPD. They activate toll-like receptors (TLRs 3, 7, and 8, leading to a pro-inflammatory response. We have characterized the responses of TLR3 and TLR7/8 in lung tissue explants from COPD patients and control smokers.Methods: We prepared lung whole tissue explants (WTEs from patients undergoing surgery for confirmed or suspected lung cancer. In order to mimic the conditions of viral infection, we used poly(I:C for TLR3 stimulation and R848 for TLR7/8 stimulation. These TLR ligands were used alone and in combination. The effects of tumor necrosis factor α (TNFα neutralization and dexamethasone on TLR responses were examined. Inflammatory cytokine release was measured by enzyme-linked immunosorbent assay and gene expression by quantitative real-time polymerase chain reaction.Results: WTEs from COPD patients released higher levels of pro-inflammatory cytokines compared with WTEs from smokers. Activation of multiple TLRs led to a greater than additive release of TNFα and CCL5. TNFα neutralization and dexamethasone treatment decreased cytokine release.Conclusion: This WTE model shows an enhanced response of COPD compared with controls, suggesting an increased response to viral infection. There was amplification of innate immune responses with multiple TLR stimulation. Keywords: COPD, poly(I:C, R848, cytokines, lung explant

  18. 2-Azidoalkoxy-7-hydro-8-oxoadenine derivatives as TLR7 agonists inducing dendritic cell maturation.

    Science.gov (United States)

    Weterings, Jimmy J; Khan, Selina; van der Heden van Noort, Gerbrand J; Melief, Cornelis J M; Overkleeft, Herman S; van der Burg, Sjoerd H; Ossendorp, Ferry; van der Marel, Gijsbert A; Filippov, Dmitri V

    2009-04-15

    The synthesis of an array of 2-azidoalkoxy substituted 7-hydro-8-oxoadenines is described. The relation of the structure of these compounds and their ability to induce maturation of dendritic cells is evaluated.

  19. A five-amino-acid motif in the undefined region of the TLR8 ectodomain is required for species-specific ligand recognition.

    Science.gov (United States)

    Liu, Jin; Xu, Congfeng; Hsu, Li-Chung; Luo, Yunping; Xiang, Rong; Chuang, Tsung-Hsien

    2010-02-01

    Toll-like receptors play important roles in regulating immunity against microbial infections. Toll-like receptor 8 (TLR8) belongs to a subfamily comprising TLR7, TLR8 and TLR9. Human TLR8 mediates anti-viral immunity by recognizing ssRNA viruses, and triggers potent anti-viral and antitumor immune responses upon ligation by synthetic small molecular weight ligands. Interestingly, distinct from human TLR8, mouse TLR8 was not responsive to ligand stimulation in the absence of polyT-oligodeoxynucleotides (polyT-ODN). The molecular basis for this distinct ligand recognition is still unclear. In the present study, we compared the activation of TLR8 from different species including mouse, rat, human, bovine, porcine, horse, sheep, and cat by ligand ligations. Only the TLR8s from the rodent species (i.e., mouse and rat TLR8s) failed to respond to ligand stimulation in the absence of polyT-ODN. Multiple sequence alignment analysis suggested that these two rodent TLR8s lack a five-amino-acid motif that is conserved in the non-rodent species with varied sequence. This small motif is located in an undefined region of the hTLR8 ectodomain, immediately following LRR-14. Deletion mutation analysis suggested that this motif is essential for the species-specific ligand recognition of hTLR8, whereas it is not required for self-dimerization and intracellular localization of this receptor. (c) 2009 Elsevier Ltd. All rights reserved.

  20. Andrographolide inhibits multiple myeloma cells by inhibiting the TLR4/NF-κB signaling pathway.

    Science.gov (United States)

    Gao, Hui; Wang, Jianrong

    2016-02-01

    Andrographolide is an active component from the extract of Andrographis paniculata [(Burm.f) Nees], a medicinal plant from the Acanthaceae family. Pharmacological studies have revealed that andrographolide possesses anti-bacterial, anti-inflammatory, anti-viral, immune regulatory and hepatoprotective properties, and is efficacious in the treatment of cardiovascular diseases, while exhibiting low toxicity and low cost. The present study aimed to determine the inhibitory effects of andrographolide on the growth of multiple myeloma (MM) cells and its possible impact on the Toll-like receptor (TLR)4/nuclear factor (NF)-κB signaling pathway. Cell proliferation was detected using an MTT assay, cellular apoptosis was measured using flow cytometry, and caspase-9/3 activation were assessed using colorimetric assay kits. Furthermore, TLR4 and NF-κB protein expression was determined by western blot analysis. The results revealed that andrographolide reduced the proliferation, while increasing cellular apoptosis and caspase-9/3 activation of MM cells, in addition to downregulating the expression of TLR4 and NF-κB protein. Of note, TLR4- or NF-κB-targeting small-interfering (si)RNA enhanced the andrographolide-induced inhibition of cell proliferation and induction of apoptosis of MM cells. The results of the present study therefore suggested that andrographolide inhibited multiple myeloma cells via the TLR4/NF-κB signaling pathway.

  1. Polymorphisms within the Toll-Like Receptor (TLR-2, -4, and -6 Genes in Cattle

    Directory of Open Access Journals (Sweden)

    Marco Mariotti

    2009-07-01

    Full Text Available In mammals, members of the TLR gene family play a primary role in the recognition of pathogen-associated molecular patterns from bacteria, viruses, protozoa and fungi. Recently, cattle TLR genes have been mapped to chromosomes using a radiation hybrid panel. Nucleotide sequences of bovine TLR2, TLR4 and TLR6 genes were screened to identify novel SNPs that can be used in studies of cattle resistance to diseases. In total, 8 SNPs were identified and were submitted to the NCBI dbSNP database. The frequencies of the SNPs were assessed in 16 different bovine European cattle breeds and a phylogenetic analysis carried out to describe the relationships between the breeds. Even if from our analysis the SNPs do not appear located in loci under selection, a deviation of three SNPs from Hardy Weinberg equilibrium was observed, and we hypothesize that some of the polymorphisms may be fixated since many generations. The described variations in immune function related genes will contribute to research on disease response in cattle. In fact, the SNPs can be used in association studies between polymorphisms and cattle resistance to diseases.

  2. Increased TLR4 expression in murine placentas after oral infection with periodontal pathogens

    Science.gov (United States)

    Arce, R.M.; Barros, S.P.; Wacker, B.; Peters, B.; Moss, K.; Offenbacher, S.

    2009-01-01

    Maternal periodontitis has emerged as a putative risk factor for preterm births in humans. The periodontitis-associated dental biofilm is thought to serve as an important source of oral bacteria and related virulence factors that hematogenously disseminate and affect the fetoplacental unit; however the underlying biological mechanisms are yet to be fully elucidated. This study hypothesized that an oral infection with the human periodontal pathogens Campylobacter rectus and Porphyromonas gingivalis is able to induce fetal growth restriction, placental inflammation and enhance Toll-like receptors type 4 (TLR4) expression in a murine pregnancy model. Female Balb/C mice (n=40) were orally infected with C. rectus and/or P. gingivalis over a 16-week period and mated once per week. Pregnant mice were sacrificed at embryonic day (E) 16.5 and placentas were collected and analyzed for TLR4 mRNA levels and qualitative protein expression by real time PCR and immunofluorescence. TLR4 mRNA expression was found to be increased in C. rectus-infected group (1.98±0.886 fold difference, Pperiodontal pathogens. The TLR4 pathway has been implicated in the pathogenesis of preterm births; therefore the abnormal regulation of placental TLR4 may give new insights into how maternal periodontitis and periodontal pathogens might be linked to placental inflammation and preterm birth pathogenesis. PMID:19101032

  3. Cellular Decision Making by Non-Integrative Processing of TLR Inputs

    Directory of Open Access Journals (Sweden)

    Ryan A. Kellogg

    2017-04-01

    Full Text Available Cells receive a multitude of signals from the environment, but how they process simultaneous signaling inputs is not well understood. Response to infection, for example, involves parallel activation of multiple Toll-like receptors (TLRs that converge on the nuclear factor κB (NF-κB pathway. Although we increasingly understand inflammatory responses for isolated signals, it is not clear how cells process multiple signals that co-occur in physiological settings. We therefore examined a bacterial infection scenario involving co-stimulation of TLR4 and TLR2. Independent stimulation of these receptors induced distinct NF-κB dynamic profiles, although surprisingly, under co-stimulation, single cells continued to show ligand-specific dynamic responses characteristic of TLR2 or TLR4 signaling rather than a mixed response, comprising a cellular decision that we term “non-integrative” processing. Iterating modeling and microfluidic experiments revealed that non-integrative processing occurred through interaction of switch-like NF-κB activation, receptor-specific processing timescales, cell-to-cell variability, and TLR cross-tolerance mediated by multilayer negative feedback.

  4. Gut microbial colonization orchestrates TLR2 expression, signaling and epithelial proliferation in the small intestinal mucosa.

    Directory of Open Access Journals (Sweden)

    Nives Hörmann

    Full Text Available The gut microbiota is an environmental factor that determines renewal of the intestinal epithelium and remodeling of the intestinal mucosa. At present, it is not resolved if components of the gut microbiota can augment innate immune sensing in the intestinal epithelium via the up-regulation of Toll-like receptors (TLRs. Here, we report that colonization of germ-free (GF Swiss Webster mice with a complex gut microbiota augments expression of TLR2. The microbiota-dependent up-regulation of components of the TLR2 signaling complex could be reversed by a 7 day broad-spectrum antibiotic treatment. TLR2 downstream signaling via the mitogen-activated protein kinase (ERK1/2 and protein-kinase B (AKT induced by bacterial TLR2 agonists resulted in increased proliferation of the small intestinal epithelial cell line MODE-K. Mice that were colonized from birth with a normal gut microbiota (conventionally-raised; CONV-R showed signs of increased small intestinal renewal and apoptosis compared with GF controls as indicated by elevated mRNA levels of the proliferation markers Ki67 and Cyclin D1, elevated transcripts of the apoptosis marker Caspase-3 and increased numbers of TUNEL-positive cells per intestinal villus structure. In accordance, TLR2-deficient mice showed reduced proliferation and reduced apoptosis. Our findings suggest that a tuned proliferation response of epithelial cells following microbial colonization could aid to protect the host from its microbial colonizers and increase intestinal surface area.

  5. TLR4 Signaling Pathway Modulators as Potential Therapeutics in Inflammation and Sepsis

    Directory of Open Access Journals (Sweden)

    Nikolay N. Kuzmich

    2017-10-01

    Full Text Available Toll-Like Receptor 4 (TLR4 signal pathway plays an important role in initiating the innate immune response and its activation by bacterial endotoxin is responsible for chronic and acute inflammatory disorders that are becoming more and more frequent in developed countries. Modulation of the TLR4 pathway is a potential strategy to specifically target these pathologies. Among the diseases caused by TLR4 abnormal activation by bacterial endotoxin, sepsis is the most dangerous one because it is a life-threatening acute system inflammatory condition that still lacks specific pharmacological treatment. Here, we review molecules at a preclinical or clinical phase of development, that are active in inhibiting the TLR4-MyD88 and TLR4-TRIF pathways in animal models. These are low-molecular weight compounds of natural and synthetic origin that can be considered leads for drug development. The results of in vivo studies in the sepsis model and the mechanisms of action of drug leads are presented and critically discussed, evidencing the differences in treatment results from rodents to humans.

  6. TLR4 mutation reduces microglial activation, increases Aβ deposits and exacerbates cognitive deficits in a mouse model of Alzheimer's disease

    Directory of Open Access Journals (Sweden)

    Song Min

    2011-08-01

    Full Text Available Abstract Background Amyloid plaques, a pathological hallmark of Alzheimer's disease (AD, are accompanied by activated microglia. The role of activated microglia in the pathogenesis of AD remains controversial: either clearing Aβ deposits by phagocytosis or releasing proinflammatory cytokines and cytotoxic substances. Microglia can be activated via toll-like receptors (TLRs, a class of pattern-recognition receptors in the innate immune system. We previously demonstrated that an AD mouse model homozygous for a loss-of-function mutation of TLR4 had increases in Aβ deposits and buffer-soluble Aβ in the brain as compared with a TLR4 wild-type AD mouse model at 14-16 months of age. However, it is unknown if TLR4 signaling is involved in initiation of Aβ deposition as well as activation and recruitment of microglia at the early stage of AD. Here, we investigated the role of TLR4 signaling and microglial activation in early stages using 5-month-old AD mouse models when Aβ deposits start. Methods Microglial activation and amyloid deposition in the brain were determined by immunohistochemistry in the AD models. Levels of cerebral soluble Aβ were determined by ELISA. mRNA levels of cytokines and chemokines in the brain and Aβ-stimulated monocytes were quantified by real-time PCR. Cognitive functions were assessed by the Morris water maze. Results While no difference was found in cerebral Aβ load between AD mouse models at 5 months with and without TLR4 mutation, microglial activation in a TLR4 mutant AD model (TLR4M Tg was less than that in a TLR4 wild-type AD model (TLR4W Tg. At 9 months, TLR4M Tg mice had increased Aβ deposition and soluble Aβ42 in the brain, which were associated with decrements in cognitive functions and expression levels of IL-1β, CCL3, and CCL4 in the hippocampus compared to TLR4W Tg mice. TLR4 mutation diminished Aβ-induced IL-1β, CCL3, and CCL4 expression in monocytes. Conclusion This is the first demonstration of TLR4

  7. Plasmid-cured Chlamydia caviae activates TLR2-dependent signaling and retains virulence in the guinea pig model of genital tract infection.

    Science.gov (United States)

    Frazer, Lauren C; Darville, Toni; Chandra-Kuntal, Kumar; Andrews, Charles W; Zurenski, Matthew; Mintus, Margaret; AbdelRahman, Yasser M; Belland, Robert J; Ingalls, Robin R; O'Connell, Catherine M

    2012-01-01

    Loss of the conserved "cryptic" plasmid from C. trachomatis and C. muridarum is pleiotropic, resulting in reduced innate inflammatory activation via TLR2, glycogen accumulation and infectivity. The more genetically distant C. caviae GPIC is a natural pathogen of guinea pigs and induces upper genital tract pathology when inoculated intravaginally, modeling human disease. To examine the contribution of pCpGP1 to C. caviae pathogenesis, a cured derivative of GPIC, strain CC13, was derived and evaluated in vitro and in vivo. Transcriptional profiling of CC13 revealed only partial conservation of previously identified plasmid-responsive chromosomal loci (PRCL) in C. caviae. However, 2-deoxyglucose (2DG) treatment of GPIC and CC13 resulted in reduced transcription of all identified PRCL, including glgA, indicating the presence of a plasmid-independent glucose response in this species. In contrast to plasmid-cured C. muridarum and C. trachomatis, plasmid-cured C. caviae strain CC13 signaled via TLR2 in vitro and elicited cytokine production in vivo similar to wild-type C. caviae. Furthermore, inflammatory pathology induced by infection of guinea pigs with CC13 was similar to that induced by GPIC, although we observed more rapid resolution of CC13 infection in estrogen-treated guinea pigs. These data indicate that either the plasmid is not involved in expression or regulation of virulence in C. caviae or that redundant effectors prevent these phenotypic changes from being observed in C. caviae plasmid-cured strains.

  8. Plasmid-cured Chlamydia caviae activates TLR2-dependent signaling and retains virulence in the guinea pig model of genital tract infection.

    Directory of Open Access Journals (Sweden)

    Lauren C Frazer

    Full Text Available Loss of the conserved "cryptic" plasmid from C. trachomatis and C. muridarum is pleiotropic, resulting in reduced innate inflammatory activation via TLR2, glycogen accumulation and infectivity. The more genetically distant C. caviae GPIC is a natural pathogen of guinea pigs and induces upper genital tract pathology when inoculated intravaginally, modeling human disease. To examine the contribution of pCpGP1 to C. caviae pathogenesis, a cured derivative of GPIC, strain CC13, was derived and evaluated in vitro and in vivo. Transcriptional profiling of CC13 revealed only partial conservation of previously identified plasmid-responsive chromosomal loci (PRCL in C. caviae. However, 2-deoxyglucose (2DG treatment of GPIC and CC13 resulted in reduced transcription of all identified PRCL, including glgA, indicating the presence of a plasmid-independent glucose response in this species. In contrast to plasmid-cured C. muridarum and C. trachomatis, plasmid-cured C. caviae strain CC13 signaled via TLR2 in vitro and elicited cytokine production in vivo similar to wild-type C. caviae. Furthermore, inflammatory pathology induced by infection of guinea pigs with CC13 was similar to that induced by GPIC, although we observed more rapid resolution of CC13 infection in estrogen-treated guinea pigs. These data indicate that either the plasmid is not involved in expression or regulation of virulence in C. caviae or that redundant effectors prevent these phenotypic changes from being observed in C. caviae plasmid-cured strains.

  9. TLR2 and TLR4 signaling pathways are required for recombinant Brucella abortus BCSP31-induced cytokine production, functional upregulation of mouse macrophages, and the Th1 immune response in vivo and in vitro.

    Science.gov (United States)

    Li, Jia-Yun; Liu, Yuan; Gao, Xiao-Xue; Gao, Xiang; Cai, Hong

    2014-09-01

    Brucella abortus is a zoonotic Gram-negative pathogen that causes brucelosis in ruminants and humans. Toll-like receptors (TLRs) recognize Brucella abortus and initiate antigen-presenting cell activities that affect both innate and adaptive immunity. In this study, we focused on recombinant Brucella cell-surface protein 31 (rBCSP31) to determine its effects on mouse macrophages. Our results demonstrated that rBCSP31 induced TNF-α, IL-6 and IL-12p40 production, which depended on the activation of mitogen-activated protein kinases (MAPKs) by stimulating the rapid phosphorylation of p38 and JNK and the activation of transcription factor NF-κB in macrophages. In addition, continuous exposure (>24 h) of RAW264.7 cells to rBCSP31 significantly enhanced IFN-γ-induced expression of MHC-II and the ability to present rBCSP31 peptide to CD4(+) T cells. Furthermore, we found that rBCSP31 could interact with both TLR2 and TLR4. The rBCSP31-induced cytokine production by macrophages from TLR2(-/-) and TLR4(-/-) mice was lower than that from C57BL/6 macrophages, and the activation of NF-κB and MAPKs was attenuated in macrophages from TLR2(-/-) and TLR4(-/-) mice. In addition, CD4(+) T cells from C57BL/6 mice immunized with rBCSP31 produced higher levels of IFN-γ and IL-2 compared with CD4(+) T cells from TLR2(-/-) and TLR4(-/-) mice. Macrophages from immunized C57BL/6 mice produced higher levels of IL-12p40 than those from TLR2(-/-) and TLR4(-/-) mice. Furthermore, immunization with rBCSP31 provided better protection in C57BL/6 mice than in TLR2(-/-) and TLR4(-/-) mice after B. abortus 2308 challenge. These results indicate that rBCSP31 is a TLR2 and TLR4 agonist that induces cytokine production, upregulates macrophage function and induces the Th1 immune response.

  10. A method for determining customer requirement weights based on TFMF and TLR

    Science.gov (United States)

    Ai, Qingsong; Shu, Ting; Liu, Quan; Zhou, Zude; Xiao, Zheng

    2013-11-01

    'Customer requirements' (CRs) management plays an important role in enterprise systems (ESs) by processing customer-focused information. Quality function deployment (QFD) is one of the main CRs analysis methods. Because CR weights are crucial for the input of QFD, we developed a method for determining CR weights based on trapezoidal fuzzy membership function (TFMF) and 2-tuple linguistic representation (TLR). To improve the accuracy of CR weights, we propose to apply TFMF to describe CR weights so that they can be appropriately represented. Because the fuzzy logic is not capable of aggregating information without loss, TLR model is adopted as well. We first describe the basic concepts of TFMF and TLR and then introduce an approach to compute CR weights. Finally, an example is provided to explain and verify the proposed method.

  11. Distinct evolution of TLR-mediated dendritic cell cytokine secretion in patients with limited and diffuse cutaneous systemic sclerosis.

    NARCIS (Netherlands)

    Bon, L. van; Popa, C.; Huibens, R.J.F.; Vonk, M.C.; York, M.; Simms, R.; Hesselstrand, R.; Wuttge, D.M.; Lafyatis, R.; Radstake, T.R.D.J.

    2010-01-01

    BACKGROUND: Systemic sclerosis (SSc) is an autoimmune disease and accumulating evidence suggests a role for Toll-like receptor (TLR)-mediated activation of dendritic cells (DCs). OBJECTIVE: To map TLR-mediated cytokine responses of DCs from patients with SSc. METHODS: 45 patients with SSc were

  12. DMPD: Toll-like receptor (TLR)-based networks regulate neutrophilic inflammation inrespiratory disease. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 18031251 Toll-like receptor (TLR)-based networks regulate neutrophilic inflammation inrespiratory...l) (.csml) Show Toll-like receptor (TLR)-based networks regulate neutrophilic inflammation inrespiratory dis...utrophilic inflammation inrespiratory disease. Authors Sabroe I, Whyte MK. Publication Biochem Soc Trans. 20

  13. Toll-like receptor 4 (TLR4) deficient mice are protected from adipose tissue inflammation in aging.

    Science.gov (United States)

    Ghosh, Amiya K; O'Brien, Martin; Mau, Theresa; Yung, Raymond

    2017-09-07

    Adipose tissue (AT) inflammation is a central mechanism for metabolic dysfunction in both diet-induced obesity and age-associated obesity. Studies in diet-induced obesity have characterized the role of Fetuin A (Fet A) in Free Fatty Acids (FFA)-mediated TLR4 activation and adipose tissue inflammation. However, the role of Fet A & TLR4 in aging-related adipose tissue inflammation is unknown. In the current study, analysis of epidymymal fat pads of C57/Bl6 male mice, we found that, in contrast to data from diet-induced obesity models, adipose tissue from aged mice have normal Fet A and TLR4 expression. Interestingly, aged TLR4-deficient mice have diminished adipose tissue inflammation compared to normal controls. We further demonstrated that reduced AT inflammation in old TLR4-deficient mice is linked to impaired ER stress, augmented autophagy activity, and diminished senescence phenomenon. Importantly, old TLR4-deficient mice have improved glucose tolerance compared to age-matched wild type mice, suggesting that the observed reduced AT inflammation in aged TLR4-deficient mice has important physiological consequences. Taken together, our present study establishes novel aspect of aging-associated AT inflammation that is distinct from diet-induced AT inflammation. Our results also provide strong evidence that TLR4 plays a significant role in promoting aging adipose tissue inflammation.

  14. TLR-related pathway analysis : novel gene-gene interactions in the development of asthma and atopy

    NARCIS (Netherlands)

    Reijmerink, N. E.; Bottema, R. W. B.; Kerkhof, M.; Gerritsen, J.; Stelma, F. F.; Thijs, C.; van Schayck, C. P.; Smit, H. A.; Brunekreef, B.; Koppelman, G. H.; Postma, D. S.

    P>Background: The toll-like receptor (TLR)-related pathway is important in host defence and may be crucial in the development of asthma and atopy. Numerous studies have shown associations of TLR-related pathway genes with asthma and atopy phenotypes. So far it has not been investigated whether

  15. Structure-Activity Relationship in TLR4 Mutations: Atomistic Molecular Dynamics Simulations and Residue Interaction Network Analysis

    Science.gov (United States)

    Anwar, Muhammad Ayaz; Choi, Sangdun

    2017-03-01

    Toll-like receptor 4 (TLR4), a vital innate immune receptor present on cell surfaces, initiates a signaling cascade during danger and bacterial intrusion. TLR4 needs to form a stable hexamer complex, which is necessary to dimerize the cytoplasmic domain. However, D299G and T399I polymorphism may abrogate the stability of the complex, leading to compromised TLR4 signaling. Crystallography provides valuable insights into the structural aspects of the TLR4 ectodomain; however, the dynamic behavior of polymorphic TLR4 is still unclear. Here, we employed molecular dynamics simulations (MDS), as well as principal component and residue network analyses, to decipher the structural aspects and signaling propagation associated with mutations in TLR4. The mutated complexes were less cohesive, displayed local and global variation in the secondary structure, and anomalous decay in rotational correlation function. Principal component analysis indicated that the mutated complexes also exhibited distinct low-frequency motions, which may be correlated to the differential behaviors of these TLR4 variants. Moreover, residue interaction networks (RIN) revealed that the mutated TLR4/myeloid differentiation factor (MD) 2 complex may perpetuate abnormal signaling pathways. Cumulatively, the MDS and RIN analyses elucidated the mutant-specific conformational alterations, which may help in deciphering the mechanism of loss-of-function mutations.

  16. Elevated muscle TLR4 expression and metabolic endotoxemia in human aging.

    Science.gov (United States)

    Ghosh, Sangeeta; Lertwattanarak, Raweewan; Garduño, Jose de Jesus; Galeana, Joaquin Joya; Li, Jinqi; Zamarripa, Frank; Lancaster, Jack L; Mohan, Sumathy; Hussey, Sophie; Musi, Nicolas

    2015-02-01

    Aging is associated with alterations in glucose metabolism and sarcopenia that jointly contribute to a higher risk of developing type 2 diabetes. Because aging is considered as a state of low-grade inflammation, in this study we examined whether older, healthy (lean, community-dwelling) participants have altered signaling flux through toll-like receptor 4 (TLR4), a key mediator of innate and adaptive immune responses. We also examined whether a 4-month aerobic exercise program would have an anti-inflammatory effect by reducing TLR4 expression and signaling. At baseline, muscle TLR4, nuclear factor κB p50 and nuclear factor κB p65 protein content, and c-Jun N-terminal kinase phosphorylation were significantly elevated in older versus young participants. The plasma concentration of the TLR4 agonist lipopolysaccharide and its binding protein also were significantly elevated in older participants, indicative of metabolic endotoxemia, which is a recently described phenomenon of increased plasma endotoxin level in metabolic disease. These alterations in older participants were accompanied by decreased insulin sensitivity, quadriceps muscle volume, and muscle strength. The exercise training program increased insulin sensitivity, without affecting quadriceps muscle volume or strength. Muscle TLR4, nuclear factor κB, and c-Jun N-terminal kinase, and plasma lipopolysaccharide and lipopolysaccharide binding protein were not changed by exercise. In conclusion, insulin resistance and sarcopenia of aging are associated with increased TLR4 expression/signaling, which may be secondary to metabolic endotoxemia. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Impact of TLR4 on behavioral and cognitive dysfunctions associated with alcohol-induced neuroinflammatory damage.

    Science.gov (United States)

    Pascual, María; Baliño, Pablo; Alfonso-Loeches, Silvia; Aragón, Carlos M G; Guerri, Consuelo

    2011-06-01

    Toll-like receptors (TLRs) play an important role in the innate immune response, and emerging evidence indicates their role in brain injury and neurodegeneration. Our recent results have demonstrated that ethanol is capable of activating glial TLR4 receptors and that the elimination of these receptors in mice protects against ethanol-induced glial activation, induction of inflammatory mediators and apoptosis. This study was designed to assess whether ethanol-induced inflammatory damage causes behavioral and cognitive consequences, and if behavioral alterations are dependent of TLR4 functions. Here we show in mice drinking alcohol for 5months, followed by a 15-day withdrawal period, that activation of the astroglial and microglial cells in frontal cortex and striatum is maintained and that these events are associated with cognitive and anxiety-related behavioral impairments in wild-type (WT) mice, as demonstrated by testing the animals with object memory recognition, conditioned taste aversion and dark and light box anxiety tasks. Mice lacking TLR4 receptors are protected against ethanol-induced inflammatory damage, and behavioral associated effects. We further assess the possibility of the epigenetic modifications participating in short- or long-term behavioral effects associated with neuroinflammatory damage. We show that chronic alcohol treatment decreases H4 histone acetylation and histone acetyltransferases activity in frontal cortex, striatum and hippocampus of WT mice. Alterations in chromatin structure were not observed in TLR4(-/-) mice. These results provide the first evidence of the role that TLR4 functions play in the behavioral consequences of alcohol-induced inflammatory damage and suggest that the epigenetic modifications mediated by TLR4 could contribute to short- or long-term alcohol-induced behavioral or cognitive dysfunctions. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. S100A9 Interaction with TLR4 Promotes Tumor Growth

    Science.gov (United States)

    Källberg, Eva; Vogl, Thomas; Liberg, David; Olsson, Anders; Björk, Per; Wikström, Pernilla; Bergh, Anders; Roth, Johannes; Ivars, Fredrik; Leanderson, Tomas

    2012-01-01

    By breeding TRAMP mice with S100A9 knock-out (S100A9−/−) animals and scoring the appearance of palpable tumors we observed a delayed tumor growth in animals devoid of S100A9 expression. CD11b+ S100A9 expressing cells were not observed in normal prostate tissue from control C57BL/6 mice but were readily detected in TRAMP prostate tumors. Also, S100A9 expression was observed in association with CD68+ macrophages in biopsies from human prostate tumors. Delayed growth of TRAMP tumors was also observed in mice lacking the S100A9 ligand TLR4. In the EL-4 lymphoma model tumor growth inhibition was observed in S100A9−/− and TLR4−/−, but not in RAGE−/− animals lacking an alternative S100A9 receptor. When expression of immune-regulating genes was analyzed using RT-PCR the only common change observed in mice lacking S100A9 and TLR4 was a down-regulation of TGFβ expression in splenic CD11b+ cells. Lastly, treatment of mice with a small molecule (ABR-215050) that inhibits S100A9 binding to TLR4 inhibited EL4 tumor growth. Thus, S100A9 and TLR4 appear to be involved in promoting tumor growth in two different tumor models and pharmacological inhibition of S100A9-TLR4 interactions is a novel and promising target for anti-tumor therapies. PMID:22470535

  19. A flagellin-derived toll-like receptor 5 agonist stimulates cytotoxic lymphocyte-mediated tumor immunity.

    Directory of Open Access Journals (Sweden)

    Nicholas D Leigh

    Full Text Available Toll-like receptor (TLR mediated recognition of pathogen associated molecular patterns allows the immune system to rapidly respond to a pathogenic insult. The "danger context" elicited by TLR agonists allows an initially non-immunogenic antigen to become immunogenic. This ability to alter environment is highly relevant in tumor immunity, since it is inherently difficult for the immune system to recognize host-derived tumors as immunogenic. However, immune cells may have encountered certain TLR ligands associated with tumor development, yet the endogenous stimulation is typically not sufficient to induce spontaneous tumor rejection. Of special interest are TLR5 agonists, because there are no endogenous ligands that bind TLR5. CBLB502 is a pharmacologically optimized TLR5 agonist derived from Salmonella enterica flagellin. We examined the effect of CBLB502 on tumor immunity using two syngeneic lymphoma models, both of which do not express TLR5, and thus do not directly respond to CBLB502. Upon challenge with the T-cell lymphoma RMAS, CBLB502 treatment after tumor inoculation protects C57BL/6 mice from death caused by tumor growth. This protective effect is both natural killer (NK cell- and perforin-dependent. In addition, CBLB502 stimulates clearance of the B-cell lymphoma A20 in BALB/c mice in a CD8(+ T cell-dependent fashion. Analysis on the cellular level via ImageStream flow cytometry reveals that CD11b(+ and CD11c(+ cells, but neither NK nor T cells, directly respond to CBLB502 as determined by NFκB nuclear translocation. Our findings demonstrate that CBLB502 stimulates a robust antitumor response by directly activating TLR5-expressing accessory immune cells, which in turn activate cytotoxic lymphocytes.

  20. Effect of experimental ileitis on expression of tlr-2 in lymphfocytes of small intestine

    Directory of Open Access Journals (Sweden)

    A. S. Zherebiatiev

    2013-08-01

    Full Text Available Introduction Crohn’s disease and ulcerative colitis are the main clinical phenotypes of inflammatory bowel disease (IBD. Both forms of IBD can increase the incidence of gastrointestinal and colon cancers, and both ones are associated with significant morbidity and mortality worldwide. In addition, they can begin early in life and persist for long periods. The pathogenesis of IBD is complex and multifactorial. Differential alteration of Toll-like receptor (TLR expression in inflammatory bowel disease was first described 15 years ago. Studies have led to the current concept that TLRs represent key mediators of innate host defense in the intestine, and they are involved in mucosa maintaining as well as commensal homeostasis. Recent findings in diverse murine models of ileitis have helped to reveal the importance of TLR dysfunction mechanisms in IBD pathogenesis. The aim of research The aim of this study was to investigate the effect of acute ileitis on expression intensity of TLR-2 in lymphocytes of small intestine. Materials and methods Male Wistar rats with weight 200–250 g were housed in standard wire-mesh bottom cages at constant temperature of 25°C and 12/12 h light/dark cycles. The rats were given water and standard laboratory diet with no restriction prior to indomethacin injection. A total number of 20 rats were examined, including control group (n = 10. For induction of acute ileitis, rats received one subcutaneous dose of indomethacin (Sigma, 15 mg/kg. Tissue was examined on the fifth day. For histological examination sections were colored with haematoxylin and eosin. The TLR-2+cells were determined using a direct immunofluorescence technique with using monoclonal rat anti-TLR-2 antibodies. Images were taken by using a fluorescence microscope PrimoStar (ZEISS, Germany with a computer-assisted video system AxioCam 5c (ZEISS, Germany including the NIH-Image software (NIH Image version 1·46. All statistical analyses were performed

  1. PARTICIPATION OF TLR4 IN ENGULFMENT OF ESCHERICHIA COLI BY HUMAN BLOOD NEUTROPHILS IN PRESENCE OF LIPOPOLYSACCHARIDES

    Directory of Open Access Journals (Sweden)

    S. V. Zubova

    2012-01-01

    Full Text Available Abstract. TLR4 is a key player in signaling system of host cells. Possible role of TLR4 is actively discussed, e.g. its significance for phagocytosis. A capacity of neutrophils to engulf FITC-labeled E. coli bacteria upon activation with LPS of different origin was studied in presence of anti-TLR4 Mab’s (HTA125 clone. It was shown that, in whole blood, TLR4 does not play any essential role in engulfment of bacteria by the neutrophils. Phagocytic activity of neutrophils in blood increases increased after their priming with E. coli endotoxins. LPS from Rb. сapsulatus did not affect phagocytosis. In presence of endotoxins, the degree of TLR4 involvement in neutrophil phagocytosis depends on LPS structure.

  2. Phase Ib Study of Immune Biomarker Modulation with Neoadjuvant Cetuximab and TLR8 Stimulation in Head and Neck Cancer to Overcome Suppressive Myeloid Signals.

    Science.gov (United States)

    Shayan, Gulidanna; Kansy, Benjamin A; Gibson, Sandra P; Srivastava, Raghvendra M; Bryan, James Kyle; Bauman, Julie E; Ohr, James; Kim, Seungwon; Duvvuri, Umamaheswar; Clump, David A; Heron, Dwight E; Johnson, Jonas T; Hershberg, Robert M; Ferris, Robert L

    2018-01-01

    Purpose: The response rate of patients with head and neck squamous cell carcinoma (HNSCC) to cetuximab therapy is only 15% to 20%, despite frequent EGFR overexpression. Because immunosuppression is common in HNSCC, we hypothesized that adding a proinflammatory TLR8 agonist to cetuximab therapy might result in enhanced T-lymphocyte stimulation and anti-EGFR-specific priming. Experimental Design: Fourteen patients with previously untreated HNSCC were enrolled in this neoadjuvant trial and treated preoperatively with 3 to 4 weekly doses of motolimod (2.5 mg/m 2 ) and cetuximab. Correlative tumor and peripheral blood specimens were obtained at baseline and at the time of surgical resection and analyzed for immune biomarker changes. Preclinical in vitro studies were also performed to assess the effect of cetuximab plus motolimod on myeloid cells. Results: TLR8 stimulation skewed monocytes toward an M1 phenotype and reversed myeloid-derived suppressor cell (MDSC) suppression of T-cell proliferation in vitro These data were validated in a prospective phase Ib neoadjuvant trial, in which fewer MDSC and increased M1 monocyte infiltration were found in tumor-infiltrating lymphocytes. Motolimod plus cetuximab also decreased induction of Treg and reduced markers of suppression, including CTLA-4, CD73, and membrane-bound TGFβ. Significantly increased circulating EGFR-specific T cells were observed, concomitant with enhanced CD8 + T-cell infiltration into tumors. These T cells manifested increased T-cell receptor (TCR) clonality, upregulation of the costimulatory receptor CD27, and downregulation of inhibitory receptor TIGIT. Conclusions: Enhanced inflammatory stimulation in the tumor microenvironment using a TLR agonist overcomes suppressive myeloid and regulatory cells, enhancing the cellular antitumor immune response by therapeutic mAb in HNSCC. Clin Cancer Res; 24(1); 62-72. ©2017 AACR . ©2017 American Association for Cancer Research.

  3. Atopy and new-onset asthma in young Danish farmers and CD14, TLR2, and TLR4 genetic polymorphisms: a nested case-control study

    DEFF Research Database (Denmark)

    Smit, L A M; Bongers, S I M; Ruven, H J T

    2007-01-01

    BACKGROUND: Evidence exists that exposure to high levels of microbial agents such as endotoxin in the farm environment decreases the risk of atopic sensitization. Genetic variation in innate immunity genes may modulate the response to microbial agents and thus influence susceptibility to asthma...... and atopy. OBJECTIVE: To study potential associations between single nucleotide polymorphisms (SNPs) in CD14, Toll-like receptor 2 (TLR2), and TLR4 genes, and atopy and new-onset asthma in young farmers. METHODS: A nested case-control study was conducted within a cohort of 1901 young Danish farmers. We....../-651 promoter polymorphisms are associated with atopy prevalence among young adults exposed to farm environments. Udgivelsesdato: 2007-Nov...

  4. Role of Extracellular RNA and TLR3‐Trif Signaling in Myocardial Ischemia–Reperfusion Injury

    Science.gov (United States)

    Chen, Chan; Feng, Yan; Zou, Lin; Wang, Larry; Chen, Howard H.; Cai, Jia‐Yan; Xu, Jun‐Mei; Sosnovik, David E.; Chao, Wei

    2014-01-01

    Background Toll‐like receptor 3 (TLR3) was originally identified as the receptor for viral RNA and represents a major host antiviral defense mechanism. TLR3 may also recognize extracellular RNA (exRNA) released from injured tissues under certain stress conditions. However, a role for exRNA and TLR3 in the pathogenesis of myocardial ischemic injury has not been tested. This study examined the role of exRNA and TLR3 signaling in myocardial infarction (MI), apoptosis, inflammation, and cardiac dysfunction during ischemia‐reperfusion (I/R) injury. Methods and Results Wild‐type (WT), TLR3−/−, Trif−/−, and interferon (IFN) α/β receptor‐1 deficient (IFNAR1−/−) mice were subjected to 45 minutes of coronary artery occlusion and 24 hours of reperfusion. Compared with WT, TLR3−/− or Trif−/− mice had smaller MI and better preserved cardiac function. Surprisingly, unlike TLR(2/4)‐MyD88 signaling, lack of TLR3‐Trif signaling had no impact on myocardial cytokines or neutrophil recruitment after I/R, but myocardial apoptosis was significantly attenuated in Trif−/− mice. Deletion of the downstream IFNAR1 had no effect on infarct size. Importantly, hypoxia and I/R led to release of RNA including microRNA from injured cardiomyocytes and ischemic heart, respectively. Necrotic cardiomyocytes induced a robust and dose‐dependent cytokine response in cultured cardiomyocytes, which was markedly reduced by RNase but not DNase, and partially blocked in TLR3‐deficient cardiomyocytes. In vivo, RNase administration reduced serum RNA level, attenuated myocardial cytokine production, leukocytes infiltration and apoptosis, and conferred cardiac protection against I/R injury. Conclusion TLR3‐Trif signaling represents an injurious pathway during I/R. Extracellular RNA released during I/R may contribute to myocardial inflammation and infarction. PMID:24390148

  5. Differential host response to LPS variants in amniochorion and the TLR4/MD-2 system in Macaca nemestrina

    Science.gov (United States)

    Chang, Justine; Jain, Sumita; Carl, David J.; Paolella, Louis; Darveau, Richard P.; Gravett, Michael G.; Waldorf, Kristina M. Adams

    2010-01-01

    OBJECTIVES Microbial-specific factors are likely critical in determining whether bacteria trigger preterm labor. Structural variations in lipopolysaccharide (LPS), a component of gram-negative bacteria, can determine whether LPS has an inflammatory (agonist) or anti-inflammatory (antagonist) effect through Toll-like receptor 4 (TLR4). Our objective was to determine whether amniochorion can discriminate between LPS variants in a nonhuman primate model. We also cloned Macaca nemestrina TLR4 and MD-2 and compared this complex functionally to the human homologue to establish whether nonhuman primates could be used to study TLR4 signaling in preterm birth. STUDY DESIGN Amniochorion explants from M. nemestrina were stimulated with a panel of LPS variants for 24 hours. Supernatants were analyzed for IL-1β, TNF-α, IL-6, IL-8 and prostaglandins E2 and F2α. Tissue expression of TLR1, 2, 4, 6, MyD88 and NF-kB was studied by RT-PCR. M. nemestrina TLR4 and MD2 genes were cloned and compared with their human counterparts in a recombinant TLR4 signaling system to determine LPS sensitivity. RESULTS LPS variants differentially stimulated cytokines and prostaglandins, which was not related to transcriptional changes of TLR4 or other TLRs. Nearly all elements of LPS binding and TLR4 leucine-rich repeats were conserved between humans and M. nemestrina. TLR4/MD-2 signaling complexes from both species were equally sensitive to LPS variants. CONCLUSIONS LPS variants elicit a hierarchical inflammatory response within amniochorion that may contribute to preterm birth. LPS sensitivity is similar between M. nemestrina and humans, validating M. nemestrina as an appropriate model to study TLR4 signaling in preterm birth. PMID:20619890

  6. Subcellular Localization of Large Yellow Croaker ( Larimichthys crocea) TLR21 and Expression Profiling of Its Gene in Immune Response

    Science.gov (United States)

    Sun, Qingxue; Fan, Zejun; Yao, Cuiluan

    2018-04-01

    Toll-like receptor 21 (TLR21) is a non-mammalian type TLR, and plays an important role in innate immune response in fish. In this paper, the full-length cDNA sequence of TLR21 gene was identified and characterized from large yellow croaker, Larimichthys crocea and was termed as LcTLR21. It consists of 3365 bp, including a 5'-terminal untranslated region (UTR) of 97 bp, a 3'-terminal UTR of 331 bp, and an open reading frame (ORF) of 2937 bp encoding a polypeptide of 978 amino acid residues. The deduced LcTLR21 contains a signal peptide domain at N-terminal, 12 leucine-rich repeats (LRRs) at the extracellular region, a transmembrane domain and a cytoplasmic toll-interleukin-1 receptor (TIR) domain at the C-terminal. Subcellular localization analysis revealed that the LcTLR21-GFP was constitutively expressed in cytoplasm. Tissue expression analysis indicated that LcTLR21 gene broadly expressed in most of the examined tissues, with the most predominant abundance in spleen, followed by head-kidney and liver, while the weakest expression was detected in brain. The expression level of LcTLR21 after LPS, poly I:C and Vibrio parahaemolyticus challenges was investigated in spleen, head-kidney and liver. LcTLR21 gene transcripts increased significantly in all examined tissues after the challenges, and the highest expression level was detected in liver at 24 h after poly I:C stimulation ( P < 0.05), suggesting that LcTLR21 might play a crucial role in fish resistance to viral and bacterial infections.

  7. Physiologic TLR9-CpG-DNA interaction is essential for the homeostasis of the intestinal immune system.

    Science.gov (United States)

    Hofmann, Claudia; Dunger, Nadja; Doser, Kristina; Lippert, Elisabeth; Siller, Sebastian; Edinger, Matthias; Falk, Werner; Obermeier, Florian

    2014-01-01

    Cytosine-guanosine dinucleotide (CpG) motifs are immunostimulatory components of bacterial DNA and activators of innate immunity through Toll-like receptor 9 (TLR9). Administration of CpG oligodeoxynucleotides before the onset of experimental colitis prevents intestinal inflammation by enforcement of regulatory mechanisms. It was investigated whether physiologic CpG/TLR9 interactions are critical for the homeostasis of the intestinal immune system. Mesenteric lymph node cell and lamina propria mononuclear cell (LPMC) populations from BALB/c wild-type (wt) or TLR9 mice were assessed by flow cytometry and proteome profiling. Cytokine secretion was determined and nuclear extracts were analyzed for nuclear factor kappa B (NF-κB) and cAMP response-element binding protein activity. To assess the colitogenic potential of intestinal T cells, CD4-enriched cells from LPMC of wt or TLR9 donor mice were injected intraperitoneally in recipient CB-17 SCID mice. TLR9 deficiency was accompanied by slight changes in cellular composition and phosphorylation of signaling proteins of mesenteric lymph node cell and LPMC. LPMC from TLR9 mice displayed an increased proinflammatory phenotype compared with wt LPMC. NF-κB activity in cells from TLR9 mice was enhanced, whereas cAMP response-element binding activity was reduced compared with wt. Transfer of lamina propria CD4-enriched T cells from TLR9 mice induced severe colitis, whereas wt lamina propria CD4-enriched T cells displayed an attenuated phenotype. Lack of physiologic CpG/TLR9 interaction impairs the function of the intestinal immune system indicated by enhanced proinflammatory properties. Thus, physiologic CpG/TLR interaction is essential for homeostasis of the intestinal immune system as it is required for the induction of counterregulating anti-inflammatory mechanisms.

  8. Human decidual macrophages and NK cells differentially express Toll-like receptors and display distinct cytokine profiles upon TLR stimulation.

    Directory of Open Access Journals (Sweden)

    Marion eDuriez

    2014-07-01

    Full Text Available Maternofetal pathogen transmission is partially controlled at the level of the maternal uterine mucosa at the fetal implantation site (the decidua basalis, where maternal and fetal cells are in close contact. Toll-like receptors (TLRs may play an important role in initiating rapid immune responses against pathogens in the decidua basalis, however the tolerant microenvironment should be preserved in order to allow fetal development. Here we investigated the expression and functionality of TLRs expressed by decidual macrophages (dMs and NK cells (dNKs, the major decidual immune cell populations.We report for the first time that both human dMs and dNK cells express mRNAs encoding TLRs 1-9, albeit with a higher expression level in dMs. TLR2, TLR3 and TLR4 protein expression checked by flow cytometry was positive for both dMs and dNK cells. In vitro treatment of primary dMs and dNK cells with specific TLR2, TLR3, TLR4, TLR7/8 and TLR9 agonists enhanced their secretion of pro- and anti-inflammatory cytokines, as well as cytokines and chemokines involved in immune cell crosstalk. Only dNK cells released IFN-γ, whereas only dMs released IL-1β, IL-10 and IL-12. TLR9 activation of dMs resulted in a distinct pattern of cytokine expression compared to the other TLRs. The cytokine profiles expressed by dMs and dNK cells upon TLR activation are compatible with maintenance of the fetotolerant immune environment during initiation of immune responses to pathogens at the maternofetal interface.

  9. Delivery of TLR7 agonist to monocytes and dendritic cells by DCIR targeted liposomes induces robust production of anti-cancer cytokines

    DEFF Research Database (Denmark)

    Klauber, Thomas Christopher Bogh; Laursen, Janne Marie; Zucker, Daniel

    2017-01-01

    Tumor immune escape is today recognized as an important cancer hallmark and is therefore a major focus area in cancer therapy. Monocytes and dendritic cells (DCs), which are central to creating a robust anti-tumor immune response and establishing an anti-tumorigenic microenvironment, are directly...... targeted by the tumor escape mechanisms to develop immunosuppressive phenotypes. Providing activated monocytes and DCs to the tumor tissue is therefore an attractive way to break the tumor-derived immune suppression and reinstate cancer immune surveillance. To activate monocytes and DCs with high...... as their immune activating potential in blood-derived monocytes, myeloid DCs (mDCs), and plasmacytoid DCs (pDCs). Monocytes and mDCs were targeted with high specificity over lymphocytes, and exhibited potent TLR7-specific secretion of the anti-cancer cytokines IL-12p70, IFN-α 2a, and IFN-γ. This delivery system...

  10. Chirality of TLR-2 ligand Pam3CysSK4 in fully synthetic peptide conjugates critically influences the induction of specific CD8+ T-cells.

    Science.gov (United States)

    Khan, Selina; Weterings, Jimmy J; Britten, Cedrik M; de Jong, Ana R; Graafland, Dirk; Melief, Cornelis J M; van der Burg, Sjoerd H; van der Marel, Gijs; Overkleeft, Hermen S; Filippov, Dmitri V; Ossendorp, Ferry

    2009-03-01

    Covalent conjugation of synthetic Toll-like receptor ligands (TLR-L) to synthetic antigenic peptides provides well-defined constructs that have significantly improved capacity to induce efficient priming of CD8(+) T lymphocytes in vivo. We have recently explored the cellular mechanisms underlying the efficient induction of a CD8(+) cytotoxic T lymphocyte response by such synthetic model vaccines [Khan, S., Bijker, M.S., Weterings, J.J., Tanke, H.J., Adema, G.J., van, H.T., Drijfhout, J.W., Melief, C.J., Overkleeft, H.S., van der Marel, G.A., Filippov, D.V., van der Burg, S.H., Ossendorp, F., 2007. Distinct uptake mechanisms but similar intracellular processing of two different toll-like receptor ligand-peptide conjugates in dendritic cells. J. Biol. Chem. 282, 21145-21159.]. In the current study we have investigated the behaviour of two diastereomers of the TLR-2 ligand Pam(3)CSK(4) (Pam) derivatives, namely the R- and S-epimers at C-2 of the glycerol moiety. Other studies have shown that the Pam(3)Cys based lipopeptides of R-configuration (Pam(R)) in the glycerol moiety enhanced macrophage and B-cell activation compared to those with S-configuration (Pam(S)). Here we report that Pam(R)-conjugates lead to better activation of dendritic cells than the Pam(S)-conjugates as judged by higher IL-12 secretion, upregulation of relevant markers for dendritic cell maturation. In contrast both epimers were internalized equally efficient in a clathrin-dependent manner indicating no qualitative difference in the uptake of the two stereoisomeric Pam-conjugates. We conclude that the enhanced DC activation is due to enhanced TLR-2 triggering by the Pam(R)-conjugate in contrast to the Pam(S)-conjugate. Importantly, induction of specific CD8(+) T-cells was significantly higher in mice injected with the Pam(R)-conjugates compared to mice injected with the Pam(S)-conjugate. In summary we show that the favourable effects of the Pam(R)-configuration of TLR-2 ligand can be attributed to

  11. Src Family Kinases Regulate Interferon Regulatory Factor 1 K63 Ubiquitination following Activation by TLR7/8 Vaccine Adjuvant in Human Monocytes and B Cells

    Directory of Open Access Journals (Sweden)

    Lorenza Tulli

    2018-03-01

    Full Text Available Toll-like receptors (TLRs play a key role in the activation of innate immune cells, in which their engagement leads to production of cytokines and co-stimulatory molecules. TLRs signaling requires recruitment of toll/IL-1R (TIR domain-containing adaptors, such as MyD88 and/or TRIF, and leads to activation of several transcription factors, such as NF-κB, the AP1 complex, and various members of the interferon regulatory factor (IRF family, which in turn results in triggering of several cellular functions associated with these receptors. A role for Src family kinases (SFKs in this signaling pathway has also been established. Our work and that of others have shown that this type of kinases is activated following engagement of several TLRs, and that this event is essential for the initiation of specific downstream cellular response. In particular, we have previously demonstrated that activation of SFKs is required for balanced production of pro-inflammatory cytokines by monocyte-derived dendritic cells after stimulation with R848, an agonist of human TLRs 7/8. We also showed that TLR7/8 triggering leads to an increase in interferon regulatory factor 1 (IRF-1 protein levels and that this effect is abolished by inhibition of SFKs, suggesting a critical role of these kinases in IRF-1 regulation. In this study, we first confirmed the key role of SFKs in TLR7/8 signaling for cytokine production and accumulation of IRF-1 protein in monocytes and in B lymphocytes, two other type of antigen-presenting cells. Then, we demonstrate that TLR7 triggering leads to an increase of K63-linked ubiquitination of IRF-1, which is prevented by SFKs inhibition, suggesting a key role of these kinases in posttranslational regulation of IRF-1 in the immune cells. In order to understand the mechanism that links SFKs activation to IRF-1 K63-linked ubiquitination, we examined SFKs and IRF-1 possible interactors and proved that activation of SFKs is necessary for their

  12. Should a Toll-like receptor 4 (TLR-4 agonist or antagonist be designed to treat cancer? TLR-4: its expression and effects in the ten most common cancers

    Directory of Open Access Journals (Sweden)

    Mai CW

    2013-11-01

    Full Text Available Chun Wai Mai, Yew Beng Kang, Mallikarjuna Rao PichikaDepartment of Pharmaceutical Chemistry, School of Pharmacy, International Medical University, Kuala Lumpur, MalaysiaAbstract: Toll-like receptor 4 (TLR-4 is well known for its host innate immunity. Despite the fact that TLR-4 activation confers antitumor responses; emerging evidence suggests that TLR-4 is associated with tumor development and progression. It is now clear that overactivation of TLR-4, through various immune mediators, may cause immune response dysfunction, resulting in tumorigenesis. Different cancers could have different extents of TLR-4 involvement during tumorigenesis or tumor progression. In this review, we focus on infection- and inflammation-related TLR-4 activation in noncancer and cancer cells, as well as on the current evidence about the role of TLR-4 in ten of the most common cancers, viz, head and neck cancer, lung cancer, gastrointestinal cancer, liver cancer, pancreatic cancer, skin cancer, breast cancer, ovarian cancer, cervical cancer, and prostate cancer.Keywords: drug design, cancer treatment, myeloid differentiation factor 2, MD-2, tumor progression, pathogen-associated molecular patterns, PAMPs

  13. TLR2 Controls Intestinal Carcinogen Detoxication by CYP1A1

    DEFF Research Database (Denmark)

    Do, Khoa; Fink, Lisbeth Nielsen; Jensen, Thomas Elbenhardt

    2012-01-01

    of ligands for TLR2 of bacterial origin seems to be crucial for detoxication of luminal carcinogens by CYP1A1 in the intestine. This unprecedented finding indicates a complex interplay between the immune system of the host and intestinal bacteria with detoxication mechanisms. This highlights the relevance...

  14. DMPD: LPS, TLR4 and infectious disease diversity. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available Nat Rev Microbiol. 2005 Jan;3(1):36-46. (.png) (.svg) (.html) (.csml) Show LPS, TLR4 and infectious disease... (.png) SVG File (.svg) HTML File (.html) CSML File (.csml) Open .csml file with CIOPlayer Open .csml file w

  15. Cloning and SNP screening of TLR4 gene and the association ...

    African Journals Online (AJOL)

    huis

    Human models, in particular, suggest TLR4 to be a candidate gene .... Rapid amplification of cDNA ends (RACE) was performed with a BD SMART™ RACE cDNA .... content (PIC) were calculated with software of POPGENE (Ver. 1.31).

  16. TLR Stimulation Dynamically Regulates Heme and Iron Export Gene Expression in Macrophages

    Directory of Open Access Journals (Sweden)

    Mary Philip

    2016-01-01

    Full Text Available Pathogenic bacteria have evolved multiple mechanisms to capture iron or iron-containing heme from host tissues or blood. In response, organisms have developed defense mechanisms to keep iron from pathogens. Very little of the body’s iron store is available as free heme; rather nearly all body iron is complexed with heme or other proteins. The feline leukemia virus, subgroup C (FeLV-C receptor, FLVCR, exports heme from cells. It was unknown whether FLVCR regulates heme-iron availability after infection, but given that other heme regulatory proteins are upregulated in macrophages in response to bacterial infection, we hypothesized that macrophages dynamically regulate FLVCR. We stimulated murine primary macrophages or macrophage cell lines with LPS and found that Flvcr is rapidly downregulated in a TLR4/MD2-dependent manner; TLR1/2 and TLR3 stimulation also decreased Flvcr expression. We identified several candidate TLR-activated transcription factors that can bind to the Flvcr promoter. Macrophages must balance the need to sequester iron from systemic circulating or intracellular pathogens with the macrophage requirement for heme and iron to produce reactive oxygen species. Our findings underscore the complexity of this regulation and point to a new role for FLVCR and heme export in macrophages responses to infection and inflammation.

  17. 2'-O-methyl-modified RNAs act as TLR7 antagonists.

    Science.gov (United States)

    Robbins, Marjorie; Judge, Adam; Liang, Lisa; McClintock, Kevin; Yaworski, Ed; MacLachlan, Ian

    2007-09-01

    RNA molecules such as single-stranded RNA (ssRNA) and small interfering RNA (siRNA) duplexes induce Toll-like receptor (TLR)-mediated immune stimulation after intracellular delivery. We have previously shown that selective incorporation of 2'-O-methyl (2'OMe) residues into siRNA abrogates cytokine production without reduction of gene silencing activity. Here we show that 2'OMe-modified RNA acts as a potent inhibitor of RNA-mediated cytokine induction in both human and murine systems. This activity does not require the direct incorporation of 2'OMe nucleotides into the immunostimulatory RNA or that the 2'OMe nucleotide-containing RNA be annealed as a complementary strand to form a duplex. Our results indicate that 2'OMe RNA acts as a potent antagonist of immunostimulatory RNA. We further show that 2'OMe RNA is able significantly to reduce both interferon-alpha (IFN-alpha) and interleukin-6 (IL-6) induction by the small-molecule TLR7 agonist loxoribine in human peripheral blood mononuclear cells (human PBMCs), in murine Flt3L dendritic cells (Flt3L DCs), and in vivo in mice. These results indicate that 2'OMe-modified RNA may have utility as an inhibitor of TLR7 with potential applications in the treatment of inflammatory and autoimmune diseases that involve TLR7-mediated immune stimulation.

  18. TLR-Stimulated Eosinophils Mediate Recruitment and Activation of NK Cells In Vivo.

    Science.gov (United States)

    O'Flaherty, S M; Sutummaporn, K; Häggtoft, W L; Worrall, A P; Rizzo, M; Braniste, V; Höglund, P; Kadri, N; Chambers, B J

    2017-06-01

    Eosinophils like many myeloid innate immune cells can provide cytokines and chemokines for the activation of other immune cells upon TLR stimulation. When TLR-stimulated eosinophils were inoculated i.p. into wild-type mice, and NK cells were rapidly recruited and exhibited antitumour cytotoxicity. However, when mice depleted of CD11c + cells were used, a marked decrease in the number of recruited NK cells was observed. We postulated that CpG or LPS from the injected eosinophils could be transferred to host cells, which in turn could recruit NK cells. However, by inoculating mice deficient in TLR4 or TLR9 with LPS or CpG-stimulated eosinophils respectively, NK cell recruitment was still observed alongside cytotoxicity and IFNγ production. CpG stimulation of eosinophils produced the pro-inflammatory cytokine IL-12 and the chemokine CXCL10, which are important for NK cell activation and recruitment in vivo. To demonstrate the importance of CXCL10 in NK cell recruitment, we found that CpG-stimulated eosinophils pretreated with the gut microbial metabolite butyrate had reduced expression and production of CXCL10 and IL-12 and concomitantly were poor at recruitment of NK cells and inducing IFNγ in NK cells. Therefore, eosinophils like other innate immune cells of myeloid origin can conceivably stimulate NK cell activity. In addition, products of the gut microbiota can be potential inhibitors of NK cell. © 2017 The Foundation for the Scandinavian Journal of Immunology.

  19. Suppression of TLR4-mediated inflammatory response by macrophage class A scavenger receptor (CD204)

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Koji; Komohara, Yoshihiro; Fujiwara, Yukio; Takemura, Kenichi [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Lei, XiaoFeng [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Department of Biochemistry, Showa University School of Medicine, Tokyo (Japan); Nakagawa, Takenobu [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Sakashita, Naomi [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan); Department of Human Pathology, Institute of Health Biosciences, The University of Tokushima, Tokushima (Japan); Takeya, Motohiro, E-mail: takeya@kumamoto-u.ac.jp [Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto (Japan)

    2011-08-05

    Highlights: {yields} We focused on the interaction between SR-A and TLR4 signaling in this study. {yields} SR-A deletion promoted NF{kappa}B activation in macrophages in septic model mouse. {yields} SR-A suppresses both MyD88-dependent and -independent TLR4 signaling in vitro. {yields} SR-A clears LPS binding to TLR4 which resulting in the suppression of TLR4 signals. -- Abstract: The class A scavenger receptor (SR-A, CD204), one of the principal receptors expressed on macrophages, has been found to regulate inflammatory response and attenuate septic endotoxemia. However, the detailed mechanism of this process has not yet been well characterized. To clarify the regulative mechanisms of lipopolysaccharide (LPS)-induced macrophage activation by SR-A, we evaluated the activation of Toll-like receptor 4 (TLR4)-mediated signaling molecules in SR-A-deficient (SR-A{sup -/-}) macrophages. In a septic shock model, the blood levels of tumor necrosis factor (TNF)-{alpha}, interleukin (IL)-6 and interferon (IFN)-{beta} were significantly increased in SR-A{sup -/-} mice compared to wild-type mice, and elevated nuclear factor kappa B (NF{kappa}B) activation was detected in SR-A{sup -/-} macrophages. SR-A deletion increased the production of pro-inflammatory cytokines, and the phosphorylation of mitogen-activated protein kinase (MAPK) and NF{kappa}B in vitro. SR-A deletion also promoted the nuclear translocation of NF{kappa}B and IFN regulatory factor (IRF)-3. In addition, a competitive binding assay with acetylated low-density lipoprotein, an SR-A-specific ligand, and anti-SR-A antibody induced significant activation of TLR4-mediated signaling molecules in wild-type macrophages but not in SR-A{sup -/-} macrophages. These results suggest that SR-A suppresses the macrophage activation by inhibiting the binding of LPS to TLR4 in a competitive manner and it plays a pivotal role in the regulation of the LPS-induced inflammatory response.

  20. Dysregulation of toll-like receptor (TLR) 2 expression on monocytes and upregulation of the frequency of T cells expressing TLR2 in patients with chronic hepatitis C virus infection

    DEFF Research Database (Denmark)

    Ronit, Andreas; Salem, Mohammad; Hartling, Hans J

    2013-01-01

    Toll-like receptors (TLRs) initiate inflammatory responses that may play a role in disease progression in patients infected with hepatitis C virus (HCV). TLR2 and TLR4 surface expression were assessed on CD14(+) monocytes, CD4(+) and CD8(+) T cells in treatment naïve patients with chronic HCV...... infection with fibrosis, without fibrosis, co-infected with human immunodeficiency virus (HIV), and in healthy controls. Increased expression of TLR2 was found on monocytes in HCV-infected patients with fibrosis (p...

  1. Polymorphisms at the innate immune receptor TLR2 are associated with Borrelia infection in a wild rodent population.

    Science.gov (United States)

    Tschirren, Barbara; Andersson, Martin; Scherman, Kristin; Westerdahl, Helena; Mittl, Peer R E; Råberg, Lars

    2013-05-22

    The discovery of the key role of Toll-like receptors (TLRs) in initiating innate immune responses and modulating adaptive immunity has revolutionized our understanding of vertebrate defence against pathogens. Yet, despite their central role in pathogen recognition and defence initiation, there is little information on how variation in TLRs influences disease susceptibility in natural populations. Here, we assessed the extent of naturally occurring polymorphisms at TLR2 in wild bank voles (Myodes glareolus) and tested for associations between TLR2 variants and infection with Borrelia afzelii, a common tick-transmitted pathogen in rodents and one of the causative agents of human Lyme disease. Bank voles in our population had 15 different TLR2 haplotypes (10 different haplotypes at the amino acid level), which grouped in three well-separated clusters. In a large-scale capture-mark-recapture study, we show that voles carrying TLR2 haplotypes of one particular cluster (TLR2c2) were almost three times less likely to be Borrelia infected than animals carrying other haplotypes. Moreover, neutrality tests suggested that TLR2 has been under positive selection. This is, to our knowledge, the first demonstration of an association between TLR polymorphism and parasitism in wildlife, and a striking example that genetic variation at innate immune receptors can have a large impact on host resistance.

  2. A member of the Tlr family is involved in dsRNA innate immune response in Paracentrotus lividus sea urchin.

    Science.gov (United States)

    Russo, Roberta; Chiaramonte, Marco; Matranga, Valeria; Arizza, Vincenzo

    2015-08-01

    The innate immune response involves proteins such as the membrane receptors of the Toll-like family (TLRs), which trigger different intracellular signalling pathways that are dependent on specific stimulating molecules. In sea urchins, TLR proteins are encoded by members of a large multigenic family composed of 60-250 genes in different species. Here, we report a newly identified mRNA sequence encoding a TLR protein (referred to as Pl-Tlr) isolated from Paracentrotus lividus immune cells. The partial protein sequence contained the conserved Toll/IL-1 receptor (TIR) domain, the transmembrane domain and part of the leucine repeats. Phylogenetic analysis of the Pl-Tlr protein was accomplished by comparing its sequence with those of TLRs from different classes of vertebrates and invertebrates. This analysis was suggestive of an evolutionary path that most likely represented the course of millions of years, starting from simple organisms and extending to humans. Challenge of the sea urchin immune system with poly-I:C, a chemical compound that mimics dsRNA, caused time-dependent Pl-Tlr mRNA up-regulation that was detected by QPCR. In contrast, bacterial LPS injury did not affect Pl-Tlr transcription. The study of the Tlr genes in the sea urchin model system may provide new perspectives on the role of Tlrs in the invertebrate immune response and clues concerning their evolution in a changing world. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. A TLR4/MD2 fusion protein inhibits LPS-induced pro-inflammatory signaling in hepatic stellate cells

    International Nuclear Information System (INIS)

    Schnabl, Bernd; Brandl, Katharina; Fink, Marina; Gross, Philipp; Taura, Kojiro; Gaebele, Erwin; Hellerbrand, Claus; Falk, Werner

    2008-01-01

    Activated hepatic stellate cells (HSCs) play a key role in hepatic fibrogenesis. In injured liver they are the main extracellular matrix protein producing cell type and further perpetuate hepatic injury by secretion of pro-inflammatory mediators. Since LPS-mediated signaling through toll-like receptor 4 (TLR4) has been identified as key fibrogenic signal in HSCs we aimed to test TLR4 as potential target of therapy via ligand-binding soluble receptors. Incubation of human HSCs with a fusion protein between the extracellular domain of TLR4 and MD2 which binds LPS inhibited LPS-induced NFκB and JNK activation. TLR4/MD2 abolished LPS-induced secretion of IL-6, IL-8, MCP1, and RANTES in HSCs. In addition, TLR4/MD2 fused to human IgG-Fc neutralized LPS activity. Since TLR4 mutant mice are resistant to liver fibrosis, the TLR4/MD2 soluble receptor might represent a new therapeutic molecule for liver fibrogenesis in vivo

  4. Electroacupuncture Improved Hippocampal Neurogenesis following Traumatic Brain Injury in Mice through Inhibition of TLR4 Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Yuqin Ye

    2017-01-01

    Full Text Available The protective role of electroacupuncture (EA treatment in diverse neurological diseases such as ischemic stroke is well acknowledged. However, whether and how EA act on hippocampal neurogenesis following traumatic brain injury (TBI remains poorly understood. This study aims to investigate the effect of EA on hippocampal neurogenesis and neurological functions, as well as its underlying association with toll-like receptor 4 (TLR4 signaling in TBI mice. BrdU/NeuN immunofluorescence was performed to label newborn neurons in the hippocampus after EA treatment. Water maze test and neurological severity score were used to evaluate neurological function posttrauma. The hippocampal level of TLR4 and downstream molecules and inflammatory cytokines were, respectively, detected by Western blot and enzyme-linked immunosorbent assay. EA enhanced hippocampal neurogenesis and inhibited TLR4 expression at 21, 28, and 35 days after TBI, but the beneficial effects of EA on posttraumatic neurogenesis and neurological functions were attenuated by lipopolysaccharide-induced TLR4 activation. In addition, EA exerted an inhibitory effect on both TLR4/Myd88/NF-κB and TLR4/TRIF/NF-κB pathways, as well as the inflammatory cytokine expression in the hippocampus following TBI. In conclusion, EA promoted hippocampal neurogenesis and neurological recovery through inhibition of TLR4 signaling pathway posttrauma, which may be a potential approach to improve the outcome of TBI.

  5. TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role in monocyte adhesion to vascular endothelium.

    Directory of Open Access Journals (Sweden)

    Seung Jin Lee

    Full Text Available Toll-like receptor 4 (TLR4 is known to mediate monocyte adhesion to endothelial cells, however, its role on the expression of monocyte adhesion molecules is unclear. In the present study, we investigated the role of TLR4 on the expression of monocyte adhesion molecules, and determined the functional role of TLR4-induced adhesion molecules on monocyte adhesion to endothelial cells. When THP-1 monocytes were stimulated with Kdo2-Lipid A (KLA, a specific TLR4 agonist, Mac-1 expression was markedly increased in association with an increased adhesion of monocytes to endothelial cells. These were attenuated by anti-Mac-1 antibody, suggesting a functional role of TLR4-induced Mac-1 on monocyte adhesion to endothelial cells. In monocytes treated with MK886, a 5-lipoxygenase (LO inhibitor, both Mac-1 expression and monocyte adhesion to endothelial cells induced by KLA were markedly attenuated. Moreover, KLA increased the expression of mRNA and protein of 5-LO, suggesting a pivotal role of 5-LO on these processes. In in vivo studies, KLA increased monocyte adhesion to aortic endothelium of wild-type (WT mice, which was attenuated in WT mice treated with anti-Mac-1 antibody as well as in TLR4-deficient mice. Taken together, TLR4-mediated expression of Mac-1 in monocytes plays a pivotal role on monocyte adhesion to vascular endothelium, leading to increased foam cell formation in the development of atherosclerosis.

  6. [TLR2 modulates Staphylococcus aureus-induced inflammatory response and autophagy in macrophages through PI3K signaling pathway].

    Science.gov (United States)

    Li, Shuai; Fang, Lei; Wang, Jiong; Liu, Rongyu

    2017-09-01

    Objective To investigate the molecular mechanisms of Toll-like receptor 2 (TLR2) taking part in inflammatory response in Staphylococcus aureus (SA)-induced asthma. Methods We established the cell inflammatory response model through stimulating mouse RAW264.7 macrophages with SA. The TLR2, myeloid differentiation factor 88 (MyD88), phosphoinositide-3 kinase (PI3K), nuclear factor κBp65 (NF-κBp65), phospho-NF-κBp65, beclin-1 and microtubule-associated protein 1 light chain 3B (LC3B) were detected by Western blot analysis after treatment with TLR2 small interfering RNA (siRNA) and 3-methyladenine (3-MA), and the tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) were determined by ELISA. In addition, the number of autolysosomes was observed by the laser scanning confocal microscope. Results SA-stimulated macrophages activated various signaling pathways including TLR2. TLR2 siRNA markedly repressed the expressions of PI3K, phospho-NF-κBp65, the autophagy protein beclin-1 and LC3B as well as the number of autolysosomes and the production of TNF- and IL-6. We also demonstrated that 3-MA had the same effect on autophagy and inflammation as TLR2 siRNA did. Conclusion TLR2 modulates SA-induced inflammatory response and autophagy in macrophages through PI3K signaling pathway.

  7. TLR-mediated inflammatory responses to Streptococcus pneumoniae are highly dependent on surface expression of bacterial lipoproteins.

    Science.gov (United States)

    Tomlinson, Gillian; Chimalapati, Suneeta; Pollard, Tracey; Lapp, Thabo; Cohen, Jonathan; Camberlein, Emilie; Stafford, Sian; Periselneris, Jimstan; Aldridge, Christine; Vollmer, Waldemar; Picard, Capucine; Casanova, Jean-Laurent; Noursadeghi, Mahdad; Brown, Jeremy

    2014-10-01

    Streptococcus pneumoniae infections induce inflammatory responses that contribute toward both disease pathogenesis and immunity, but the host-pathogen interactions that mediate these effects are poorly defined. We used the surface lipoprotein-deficient ∆lgt pneumococcal mutant strain to test the hypothesis that lipoproteins are key determinants of TLR-mediated immune responses to S. pneumoniae. We show using reporter assays that TLR2 signaling is dependent on pneumococcal lipoproteins, and that macrophage NF-κB activation and TNF-α release were reduced in response to the ∆lgt strain. Differences in TNF-α responses between Δlgt and wild-type bacteria were abrogated for macrophages from TLR2- but not TLR4-deficient mice. Transcriptional profiling of human macrophages revealed attenuated TLR2-associated responses to ∆lgt S. pneumoniae, comprising many NF-κB-regulated proinflammatory cytokine and chemokine genes. Importantly, non-TLR2-associated responses were preserved. Experiments using leukocytes from IL-1R-associated kinase-4-deficient patients and a mouse pneumonia model confirmed that proinflammatory responses were lipoprotein dependent. Our data suggest that leukocyte responses to bacterial lipoproteins are required for TLR2- and IL-1R-associated kinase-4-mediated inflammatory responses to S. pneumoniae. Copyright © 2014 The Authors.

  8. microRNA-124 negatively regulates TLR signaling in alveolar macrophages in response to mycobacterial infection.

    Science.gov (United States)

    Ma, Chunyan; Li, Yong; Li, Min; Deng, Guangcun; Wu, Xiaoling; Zeng, Jin; Hao, Xiujing; Wang, Xiaoping; Liu, Jing; Cho, William C S; Liu, Xiaoming; Wang, Yujiong

    2014-11-01

    The emerging roles of microRNAs (miRNAs) in regulating immune responses have attracted increasing attention in recent years; and the alveolar macrophages (AMs) are the main targets of mycobacterial infection, which play a pivotal role in the pathogenesis of Mycobacterium tuberculosis infection. However, the immunoregulatory role of miRNAs in AMs has not been fully demonstrated. In this study, we find that miR-124 is up-regulated in the peripheral leukocytes of patients with pulmonary tuberculosis; furthermore, the expression miR-124 can be induced upon Mycobacterium bovis Bacillus Calmette-Guerin (BCG) infection in both RAW264.7 AM cells in vitro and murine AMs in vivo. Mechanistically, miR-124 is able to modulate toll-like receptor (TLR) signaling activity in RAW264.7 cells in response to BCG infection. In this regard, multiple components of TLR signaling cascade, including the TLR6, myeloid differentiation factor 88 (MyD88), TNFR-associated factor 6 and tumor necrosis factor-α are directly targeted by miR-124. In addition, both overexpression of TLR signaling adaptor MyD88 and BCG infection are able to augment miR-124 transcription, while MyD88 expression silenced by small interfering RNA dramatically suppresses miR-124 expression in AMs in vitro. Moreover, the abundance of miR-124 transcript in murine AMs of MyD88 deficient mice is significantly less than that of their wild-type or heterozygous littermates; and the BCG infection fails to induce miR-124 expression in the lung of MyD88 deficient mouse. These results indicate a negative regulatory role of miR-124 in fine-tuning inflammatory response in AMs upon mycobacterial infection, in part through a mechanism by directly targeting TLR signaling. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Characteristic and functional analysis of toll-like receptors (TLRs in the lophotrocozoan, Crassostrea gigas, reveals ancient origin of TLR-mediated innate immunity.

    Directory of Open Access Journals (Sweden)

    Yang Zhang

    Full Text Available The evolution of TLR-mediated innate immunity is a fundamental question in immunology. Here, we report the characterization and functional analysis of four TLR members in the lophotrochozoans Crassostreagigas (CgTLRs. All CgTLRs bear a conserved domain organization and have a close relationship with TLRs in ancient non-vertebrate chordates. In HEK293 cells, every CgTLR could constitutively activate NF-κB responsive reporter, but none of the PAMPs tested could stimulate CgTLR-activated NF-κB induction. Subcellular localization showed that CgTLR members have similar and dual distribution on late endosomes and plasma membranes. Moreover, CgTLRs and CgMyD88 mRNA show a consistent response to multiple PAMP challenges in oyster hemocytes. As CgTLR-mediated NF-κB activation is dependent on CgMyD88, we designed a blocking peptide for CgTLR signaling that would inhibit CgTLR-CgMyD88 dependent NF-κB activation. This was used to demonstrate that a Vibrio parahaemolyticus infection-induced enhancement of degranulation and increase of cytokines TNF mRNA in hemocytes, could be inhibited by blocking CgTLR signaling. In summary, our study characterized the primitive TLRs in the lophotrocozoan C. gigas and demonstrated a fundamental role of TLR signaling in infection-induced hemocyte activation. This provides further evidence for an ancient origin of TLR-mediated innate immunity.

  10. Combined effect of TLR2 gene polymorphism and early life stress on the age at onset of bipolar disorders.

    Directory of Open Access Journals (Sweden)

    José Oliveira

    Full Text Available Gene-environment interactions may play an important role in modulating the impact of early-life stressful events on the clinical course of bipolar disorder (BD, particularly associated to early age at onset. Immune dysfunction is thought to be an important mechanism linking childhood trauma with early-onset BD, thus the genetic diversity of immune-related loci may account for an important part of the interindividual susceptibility to this severe subform. Here we investigated the potential interaction between genetic variants of Toll-like receptors 2 (TLR2 and 4 (TLR4, major innate immune response molecules to pathogens, and the childhood trauma questionnaire (CTQ in age at onset of BD. We recruited 531 BD patients (type I and II or not otherwise specified, genotyped for the TLR2 rs4696480 and rs3804099 and TLR4 rs1927914 and rs11536891 single-nucleotide polymorphisms and recorded for history of childhood trauma using the CTQ. TLR2 and TLR4 risk genotype carrier state and history of childhood emotional, physical and sexual abuses were evaluated in relation to age at onset as defined by the age at first manic or depressive episode. We observed a combined effect of TLR2 rs3804099 TT genotype and reported sexual abuse on determining an earlier age at onset of BD by means of a Kaplan-Meier survival curve (p = 0.002; corrected p = 0.02. Regression analysis, however, was non-significant for the TLR2-CTQ sexual abuse interaction term. The negative effects of childhood sexual abuse on age at onset of BD may be amplified in TLR2 rs3804099 risk genotype carriers through immune-mediated pathways. Clinical characteristics of illness severity, immune phenotypes and history of early life infectious insults should be included in future studies involving large patient cohorts.

  11. Albumin stimulates renal tubular inflammation through an HSP70-TLR4 axis in mice with early diabetic nephropathy

    Science.gov (United States)

    Jheng, Huei-Fen; Tsai, Pei-Jane; Chuang, Yi-Lun; Shen, Yi-Ting; Tai, Ting-An; Chen, Wen-Chung; Chou, Chuan-Kai; Ho, Li-Chun; Tang, Ming-Jer; Lai, Kuei-Tai A.; Sung, Junne-Ming; Tsai, Yau-Sheng

    2015-01-01

    ABSTRACT Increased urinary albumin excretion is not simply an aftermath of glomerular injury, but is also involved in the progression of diabetic nephropathy (DN). Whereas Toll-like receptors (TLRs) are incriminated in the renal inflammation of DN, whether and how albumin is involved in the TLR-related renal inflammatory response remains to be clarified. Here, we showed that both TLR2 and TLR4, one of their putative endogenous ligands [heat shock protein 70 (HSP70)] and nuclear factor-κB promoter activity were markedly elevated in the kidneys of diabetic mice. A deficiency of TLR4 but not of TLR2 alleviated albuminuria, tubulointerstitial fibrosis and inflammation induced by diabetes. The protection against renal injury in diabetic Tlr4−/− mice was associated with reduced tubular injuries and preserved cubilin levels, rather than amelioration of glomerular lesions. In vitro studies revealed that albumin, a stronger inducer than high glucose (HG), induced the release of HSP70 from proximal tubular cells. HSP70 blockade ameliorated albumin-induced inflammatory mediators. HSP70 triggered the production of inflammatory mediators in a TLR4-dependent manner. Moreover, HSP70 inhibition in vivo ameliorated diabetes-induced albuminuria, inflammatory response and tubular injury. Finally, we found that individuals with DN had higher levels of TLR4 and HSP70 in the dilated tubules than non-diabetic controls. Thus, activation of the HSP70-TLR4 axis, stimulated at least in part by albumin, in the tubular cell is a newly identified mechanism associated with induction of tubulointerstitial inflammation and aggravation of pre-existing microalbuminuria in the progression of DN. PMID:26398934

  12. Heme activates TLR4-mediated inflammatory injury via MyD88/TRIF signaling pathway in intracerebral hemorrhage

    Directory of Open Access Journals (Sweden)

    Lin Sen

    2012-03-01

    Full Text Available Abstract Background Inflammatory injury plays a critical role in intracerebral hemorrhage (ICH-induced neurological deficits; however, the signaling pathways are not apparent by which the upstream cellular events trigger innate immune and inflammatory responses that contribute to neurological impairments. Toll-like receptor 4 (TLR4 plays a role in inflammatory damage caused by brain disorders. Methods In this study, we investigate the role of TLR4 signaling in ICH-induced inflammation. In the ICH model, a significant upregulation of TLR4 expression in reactive microglia has been demonstrated using real-time RT-PCR. Activation of microglia was detected by immunohistochemistry, cytokines were measured by ELISA, MyD88, TRIF and NF-κB were measured by Western blot and EMSA, animal behavior was evaluated by animal behavioristics. Results Compared to WT mice, TLR4−/− mice had restrained ICH-induced brain damage showing in reduced cerebral edema and lower neurological deficit scores. Quantification of cytokines including IL-6, TNF-α and IL-1β and assessment of macrophage infiltration in perihematoma tissues from TLR4−/−, MyD88−/− and TRIF−/− mice showed attenuated inflammatory damage after ICH. TLR4−/− mice also exhibited reduced MyD88 and TRIF expression which was accompanied by decreased NF-κB activity. This suggests that after ICH both MyD88 and TRIF pathways might be involved in TLR4-mediated inflammatory injury possibly via NF-κB activation. Exogenous hemin administration significantly increased TLR4 expression and microglial activation in cultures and also exacerbated brain injury in WT mice but not in TLR4−/− mice. Anti-TLR4 antibody administration suppressed hemin-induced microglial activation in cultures and in the mice model of ICH. Conclusions Our findings suggest that heme potentiates microglial activation via TLR4, in turn inducing NF-κB activation via the MyD88/TRIF signaling pathway, and ultimately

  13. Polymorphisms in genes TLR1, 2 and 4 are associated with differential cytokine and chemokine serum production in patients with leprosy

    Directory of Open Access Journals (Sweden)

    Nadja de Lima Santana

    Full Text Available BACKGROUND Leprosy or hansen’s disease is a spectral disease whose clinical forms mostly depends on host’s immune and genetic factors. Different Toll-like receptors (TLR variants have been described associated with leprosy, but with some lack of replication across different populations. OBJECTIVES To evaluate the role of polymorphisms in genes TLR1, TLR2 and TLR4 and susceptibility to leprosy in a genetic case control study; to verify the association between genotypes of these markers and the immunological profile in the serum of patients with leprosy. METHODS Pre-designed TaqMan® assays were used to genotype markers at TLR1 (rs4833095, rs5743551, TLR2 (rs7656411, rs3804099 and TLR4 (rs1927914, rs1927911. A panel of cytokines and chemokines was accessed by enzime-linked immunosorbent assay (ELISA test in the serum of a subgroup of patients with and without leprosy reactions. FINDINGS Our results show an association between the T allele of rs3804099 at the TLR2 gene and increased risk for leprosy per se [Odds ratio (OR = 1.296, p = 0,022]. In addition, evaluating the association between different genotypes of the TLR1, 2 and 4 markers and cytokine/chemokine serological levels, IL-17 appears as an immunological marker regulated by the polymorphism of the three TLR genes evaluated, whereas different TLR1 genotypes were associated with differential production of IL-12p40 and MCP-1(CCL2. Furthermore, other relevant serum markers such as CXCL-10 and IL-6 seemed to be regulated by TLR2 variants and IL-1β was related to TLR4 genotypes. MAIN CONCLUSIONS All together our data points that the tested TLR markers may have a regulatory role in the immunity against Mycobacterium leprae, by driving the host’s production of key cytokines and chemokines involved in the pathogenesis of this disease.

  14. Polymorphisms in genes TLR1, 2 and 4 are associated with differential cytokine and chemokine serum production in patients with leprosy

    Science.gov (United States)

    Santana, Nadja de Lima; Rêgo, Jamile Leão; Oliveira, Joyce Moura; de Almeida, Lucas Frederico; Braz, Marcos; Machado, Lídia Maria Medeiros; Machado, Paulo Roberto Lima; Castellucci, Léa Cristina

    2017-01-01

    BACKGROUND Leprosy or hansen’s disease is a spectral disease whose clinical forms mostly depends on host’s immune and genetic factors. Different Toll-like receptors (TLR) variants have been described associated with leprosy, but with some lack of replication across different populations. OBJECTIVES To evaluate the role of polymorphisms in genes TLR1, TLR2 and TLR4 and susceptibility to leprosy in a genetic case control study; to verify the association between genotypes of these markers and the immunological profile in the serum of patients with leprosy. METHODS Pre-designed TaqMan® assays were used to genotype markers at TLR1 (rs4833095, rs5743551), TLR2 (rs7656411, rs3804099) and TLR4 (rs1927914, rs1927911). A panel of cytokines and chemokines was accessed by enzime-linked immunosorbent assay (ELISA) test in the serum of a subgroup of patients with and without leprosy reactions. FINDINGS Our results show an association between the T allele of rs3804099 at the TLR2 gene and increased risk for leprosy per se [Odds ratio (OR) = 1.296, p = 0,022]. In addition, evaluating the association between different genotypes of the TLR1, 2 and 4 markers and cytokine/chemokine serological levels, IL-17 appears as an immunological marker regulated by the polymorphism of the three TLR genes evaluated, whereas different TLR1 genotypes were associated with differential production of IL-12p40 and MCP-1(CCL2). Furthermore, other relevant serum markers such as CXCL-10 and IL-6 seemed to be regulated by TLR2 variants and IL-1β was related to TLR4 genotypes. MAIN CONCLUSIONS All together our data points that the tested TLR markers may have a regulatory role in the immunity against Mycobacterium leprae, by driving the host’s production of key cytokines and chemokines involved in the pathogenesis of this disease. PMID:28327786

  15. Polymorphisms in genes TLR1, 2 and 4 are associated with differential cytokine and chemokine serum production in patients with leprosy.

    Science.gov (United States)

    Santana, Nadja de Lima; Rêgo, Jamile Leão; Oliveira, Joyce Moura; Almeida, Lucas Frederico de; Braz, Marcos; Machado, Lídia Maria Medeiros; Machado, Paulo Roberto Lima; Castellucci, Léa Cristina

    2017-04-01

    Leprosy or hansen's disease is a spectral disease whose clinical forms mostly depends on host's immune and genetic factors. Different Toll-like receptors (TLR) variants have been described associated with leprosy, but with some lack of replication across different populations. To evaluate the role of polymorphisms in genes TLR1, TLR2 and TLR4 and susceptibility to leprosy in a genetic case control study; to verify the association between genotypes of these markers and the immunological profile in the serum of patients with leprosy. Pre-designed TaqMan® assays were used to genotype markers at TLR1 (rs4833095, rs5743551), TLR2 (rs7656411, rs3804099) and TLR4 (rs1927914, rs1927911). A panel of cytokines and chemokines was accessed by enzime-linked immunosorbent assay (ELISA) test in the serum of a subgroup of patients with and without leprosy reactions. Our results show an association between the T allele of rs3804099 at the TLR2 gene and increased risk for leprosy per se [Odds ratio (OR) = 1.296, p = 0,022]. In addition, evaluating the association between different genotypes of the TLR1, 2 and 4 markers and cytokine/chemokine serological levels, IL-17 appears as an immunological marker regulated by the polymorphism of the three TLR genes evaluated, whereas different TLR1 genotypes were associated with differential production of IL-12p40 and MCP-1(CCL2). Furthermore, other relevant serum markers such as CXCL-10 and IL-6 seemed to be regulated by TLR2 variants and IL-1β was related to TLR4 genotypes. All together our data points that the tested TLR markers may have a regulatory role in the immunity against Mycobacterium leprae, by driving the host's production of key cytokines and chemokines involved in the pathogenesis of this disease.

  16. TLR4 Asp299Gly polymorphism may be protective against chronic periodontitis.

    Science.gov (United States)

    Sellers, R M; Payne, J B; Yu, F; LeVan, T D; Walker, C; Mikuls, T R

    2016-04-01

    Periodontitis results from interplay between genetic and environmental factors. Single nucleotide polymorphisms (SNPs) in the coding region of the toll-like receptor 4 gene (TLR4) may be associated with periodontitis, although previous studies have been inconclusive. Moreover, the interaction between environmental factors, such as cigarette smoking (a major risk factor for periodontitis), and Porphyromonas gingivalis (a major periodontal pathogen) with the TLR4 coding region Asp299Gly SNP (rs4986790; a SNP associated with lipopolysaccharide-mediated inflammatory responses in periodontitis), have been largely ignored in previous reports. Therefore, the objective of this study was to examine the association between TLR4 Asp299Gly (rs4986790) with alveolar bone height loss (ABHL) and periodontitis, accounting for interactions between this SNP with smoking and P. gingivalis prevalence. The CD14/-260 SNP (rs2569190) served as a control, as a recent meta-analysis suggested no relationship between this SNP and periodontitis. This multicenter study included 617 participants who had rheumatoid arthritis or osteoarthritis. This report presents a secondary outcome from the primary case-control study examining the relationship of periodontitis with established rheumatoid arthritis. The Centers for Disease Control/American Academy of Periodontology case definitions of periodontitis were used for this analysis. Participants received a full-mouth clinical periodontal examination and panoramic radiograph. Percentage ABHL was measured on posterior teeth. The TLR4 Asp299Gly and CD14/-260 SNPs were selected a priori and genotypes were determined using the ImmunoChip array (Illumina(®) ). Minor allele frequencies and associations with periodontitis and ABHL did not differ according to rheumatoid arthritis vs. osteoarthritis status; therefore, data from these two groups were pooled. The presence of P. gingivalis was detected in subgingival plaque by PCR. Multivariate ordinal

  17. Hepatitis C Virus NS3 Mediated Microglial Inflammation via TLR2/TLR6 MyD88/NF-κB Pathway and Toll Like Receptor Ligand Treatment Furnished Immune Tolerance.

    Directory of Open Access Journals (Sweden)

    Ayilam Ramachandran Rajalakshmy

    Full Text Available Recent evidence suggests the neurotrophic potential of hepatitis C virus (HCV. HCV NS3 protein is one of the potent antigens of this virus mediating inflammatory response in different cell types. Microglia being the immune surveillance cells in the central nervous system (CNS, the inflammatory potential of NS3 on microglia was studied. Role of toll like receptor (TLR ligands Pam2CSK3 and Pam3CSK4 in controlling the NS3 mediated microglial inflammation was studied using microglial cell line CHME3.IL (Interleukin-8, IL-6, TNF-α (Tumor nicrosis factor alpha and IL-1β gene expressions were measured by semi quantitative RT-PCR (reverse transcription-PCR. ELISA was performed to detect IL-8, IL-6, TNF-α, IL-1β and IL-10 secretion. FACS (Flourescent activated cell sorting was performed to quantify TLR1, TLR2, TLR6, MyD88 (Myeloid differntiation factor 88, IkB-α (I kappaB alpha and pNF-κB (phosphorylated nuclear factor kappaB expression. Immunofluorescence staining was performed for MyD88, TLR6 and NF-κB (Nuclear factor kappaB. Student's t-test or One way analysis of variance with Bonferoni post hoc test was performed and p < 0.05 was considered significant.Microglia responded to NS3 by secreting IL-8, IL-6, TNF-α and IL-1β via TLR2 or TLR6 mediated MyD88/NF-κB pathway. Transcription factor NF-κB was involved in activating the cytokine gene expression and the resultant inflammatory response was controlled by NF-κB inhibitor, Ro106-9920, which is known to down regulate pro-inflammatory cytokine secretion. Activation of the microglia by TLR agonists Pam3CSK4 and Pam2CSK4 induced immune tolerance against NS3. TLR ligand treatment significantly down regulated pro-inflammatory cytokine secretion in the microglia. IL-10 secretion was suggested as the possible mechanism by which TLR agonists induced immune tolerance. NS3 as such was not capable of self-inducing immune tolerance in microglia.In conclusion, NS3 protein was capable of activating

  18. Activation of human CD141+ and CD1c+ dendritic cells in vivo with combined TLR3 and TLR7/8 ligation.

    Science.gov (United States)

    Pearson, Frances E; Chang, Karshing; Minoda, Yoshihito; Rojas, Ingrid M Leal; Haigh, Oscar L; Daraj, Ghazal; Tullett, Kirsteen M; Radford, Kristen J

    2018-04-01

    Mice reconstituted with human hematopoietic stem cells are valuable models to study aspects of the human immune system in vivo. We describe a humanized mouse model (hu mice) in which fully functional human CD141 + and CD1c + myeloid and CD123 + plasmacytoid dendritic cells (DC) develop from human cord blood CD34 + cells in immunodeficient mice. CD141 + DC are the human equivalents of murine CD8 + /CD103 + DC which are essential for the induction of tumor-inhibitory cytotoxic T lymphocyte responses, making them attractive targets to exploit for the development of new cancer immunotherapies. We used CD34 + -engrafted NSG-A2 mice to investigate activation of DC subsets by synthetic dsRNA or ssRNA analogs polyinosinic-polycytidylic acid/poly I:C and Resiquimod/R848, agonists for TLR3 and TLR8, respectively, both of which are expressed by CD141 + DC. Injection of hu mice with these agonists resulted in upregulation of costimulatory molecules CD80, CD83 and CD86 by CD141 + and CD1c + DC alike, and their combination further enhanced expression of these molecules by both subsets. When combined, poly I:C and R848 enhanced serum levels of key cytokines associated with cross-presentation and the induction of cytotoxic T lymphocyte responses including IFN-α, IFN-β, IL-12 and CXCL10. These data advocate a combination of poly I:C and R848 TLR agonists as means of activating human DC for immunotherapy. © 2018 Australasian Society for Immunology Inc.

  19. Signatures of positive selection in Toll-like receptor (TLR genes in mammals

    Directory of Open Access Journals (Sweden)

    Areal Helena

    2011-12-01

    Full Text Available Abstract Background Toll-like receptors (TLRs are a major class of pattern recognition receptors (PRRs expressed in the cell surface or membrane compartments of immune and non-immune cells. TLRs are encoded by a multigene family and represent the first line of defense against pathogens by detecting foreigner microbial molecular motifs, the pathogen-associated molecular patterns (PAMPs. TLRs are also important by triggering the adaptive immunity in vertebrates. They are characterized by the presence of leucine-rich repeats (LRRs in the ectodomain, which are associated with the PAMPs recognition. The direct recognition of different pathogens by TLRs might result in different evolutionary adaptations important to understand the dynamics of the host-pathogen interplay. Ten mammal TLR genes, viral (TLR3, 7, 8, 9 and non-viral (TLR1-6, 10, were selected to identify signatures of positive selection that might have been imposed by interacting pathogens and to clarify if viral and non-viral TLRs might display different patterns of molecular evolution. Results By using Maximum Likelihood approaches, evidence of positive selection was found in all the TLRs studied. The number of positively selected codons (PSC ranged between 2-26 codons (0.25%-2.65% with the non-viral TLR4 as the receptor with higher percentage of positively selected codons (2.65%, followed by the viral TLR8 (2.50%. The results indicated that viral and non-viral TLRs are similarly under positive selection. Almost all TLRs have at least one PSC located in the LRR ectodomain which underlies the importance of the pathogen recognition by this region. Conclusions Our results are not in line with previous studies on primates and birds that identified more codons under positive selection in non-viral TLRs. This might be explained by the fact that both primates and birds are homogeneous groups probably being affected by only a restricted number of related viruses with equivalent motifs to be

  20. TLR4 endogenous ligand MRP8/14 level in enthesitis-related arthritis and its association with disease activity and TLR4 expression.

    Science.gov (United States)

    Rahman, Mujeeb T; Myles, Arpita; Gaur, Priyanka; Misra, Ramnath; Aggarwal, Amita

    2014-02-01

    Enthesitis-related arthritis (ERA) is an inflammatory disease of childhood that lacks autoantibodies. Overexpression of surface-expressed Toll-like receptors (TLRs) has been found in ERA. Myeloid-related proteins (MRPs) 8 and 14 are calcium binding proteins that act as an endogenous ligand of TLR4. MRP8/14 levels are elevated in patients with systemic-onset arthritis. Thus we studied the role of MRP8/14 in ERA. The study enrolled patients with ERA. Plasma and SF levels of MRP8/14 were measured by ELISA and TLR4 expression on peripheral blood and SF monocytes was measured by two-colour flow cytometry. Control plasma samples were collected from 48 blood bank donors. Of the 69 patients, 67 were male, with a mean age of 15.2 (s.d. 2.7) years and a disease duration of 5 (s.d. 3) years. Median plasma levels of MRP8/14 were higher in patients (10 862.3 ng/ml) than controls (4426.1 ng/ml, P < 0.0001). Patients with active disease (11 669.5 ng/ml) had higher levels as compared with inactive disease (4421.8 ng/ml, P < 0.0001). Plasma MRP8/14 levels decreased on follow-up after 3 months only in patients who responded to treatment (P = 0.012). MRP8/14 levels were negatively correlated with the frequency of CD14(+)TLR4(+) cells (r = -0.372, P = 0.02). MRP8/14 levels were higher in SF as compared with plasma (15 858.45 ng/ml, P = 0.024). The frequency of CD14(+)TLR4(+) cells was higher in SF as compared with peripheral blood. MRP8/14 levels are increased in the plasma of ERA patients and are higher in those with active disease and the levels decrease in patients who respond to treatment, suggesting that it may be a good biomarker during follow-up.

  1. Bruton's tyrosine kinase mediates the synergistic signalling between TLR9 and the B cell receptor by regulating calcium and calmodulin.

    Directory of Open Access Journals (Sweden)

    Elaine F Kenny

    Full Text Available B cells signal through both the B cell receptor (BCR which binds antigens and Toll-like receptors (TLRs including TLR9 which recognises CpG DNA. Activation of TLR9 synergises with BCR signalling when the BCR and TLR9 co-localise within an auto-phagosome-like compartment. Here we report that Bruton's tyrosine kinase (BTK is required for synergistic IL6 production and up-regulation of surface expression of MHC-class-II, CD69 and CD86 in primary murine and human B cells. We show that BTK is essential for co-localisation of the BCR and TLR9 within a potential auto-phagosome-like compartment in the Namalwa human B cell line. Downstream of BTK we find that calcium acting via calmodulin is required for this process. These data provide new insights into the role of BTK, an important target for autoimmune diseases, in B cell activation.

  2. Expression patterns of porcine Toll-like receptors family set of genes (TLR1-10) in gut-associated lymphoid tissues alter with age.

    Science.gov (United States)

    Uddin, Muhammad Jasim; Kaewmala, Kanokwan; Tesfaye, Dawit; Tholen, Ernst; Looft, Christian; Hoelker, Michael; Schellander, Karl; Cinar, Mehmet Ulas

    2013-08-01

    The aim was to study the expression pattern of the porcine TLR family (TLR1-10) genes in gut-associated lymphoid tissues (GALT) of varying ages. A total of nine clinically healthy pigs of three ages group (1 day, 2 months and 5 months old) were selected for this experiment (three pigs in each group). Tissues from intestinal mucosa in stomach, duodenum, jejunum and ileum and mesenteric lymph node (MLN) were used. mRNA expression of TLRs (1-10) was detectable in all tissues and TLR3 showed the highest mRNA abundance among TLRs. TLR3 expression in stomach, and TLR1 and TLR6 expression in MLN were higher in adult than newborn pigs. The western blot results of TLR2, 3 and 9 in some cases, did not coincide with the mRNA expression results. The protein localization of TLR2, 3 and 9 showed that TLR expressing cells were abundant in the lamina propria, Peyer's patches in intestine, and around and within the lymphoid follicles in the MLN. This expressions study sheds the first light on the expression patterns of all TLR genes in GALT at different ages of pigs. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Synergic activation of toll-like receptor (TLR) 2/6 and 9 in response to Ureaplasma parvum & urealyticum in human amniotic epithelial cells.

    Science.gov (United States)

    Triantafilou, Martha; De Glanville, Benjamin; Aboklaish, Ali F; Spiller, O Brad; Kotecha, Sailesh; Triantafilou, Kathy

    2013-01-01

    Ureaplasma species are the most frequently isolated microorganisms inside the amniotic cavity and have been associated with spontaneous abortion, chorioamnionitis, premature rupture of the membranes (PROM), preterm labour (PL) pneumonia in neonates and bronchopulmonary dysplasia in neonates. The mechanisms by which Ureaplasmas cause such diseases remain unclear, but it is believed that inappropriate induction of inflammatory responses is involved, triggered by the innate immune system. As part of its mechanism of activation, the innate immune system employs germ-lined encoded receptors, called pattern recognition receptors (PRRs) in order to "sense" pathogens. One such family of PRRs are the Toll like receptor family (TLR). In the current study we aimed to elucidate the role of TLRs in Ureaplasma-induced inflammation in human amniotic epithelial cells. Using silencing, as well as human embryonic kidney (HEK) transfected cell lines, we demonstrate that TLR2, TLR6 and TLR9 are involved in the inflammatory responses against Ureaplasma parvum and urealyticum serovars. Ureaplasma lipoproteins, such as Multiple Banded antigen (MBA), trigger responses via TLR2/TLR6, whereas the whole bacterium is required for TLR9 activation. No major differences were observed between the different serovars. Cell activation by Ureaplasma parvum and urealyticum seem to require lipid raft function and formation of heterotypic receptor complexes comprising of TLR2 and TLR6 on the cell surface and TLR9 intracellularly.

  4. Synergic activation of toll-like receptor (TLR 2/6 and 9 in response to Ureaplasma parvum & urealyticum in human amniotic epithelial cells.

    Directory of Open Access Journals (Sweden)

    Martha Triantafilou

    Full Text Available Ureaplasma species are the most frequently isolated microorganisms inside the amniotic cavity and have been associated with spontaneous abortion, chorioamnionitis, premature rupture of the membranes (PROM, preterm labour (PL pneumonia in neonates and bronchopulmonary dysplasia in neonates. The mechanisms by which Ureaplasmas cause such diseases remain unclear, but it is believed that inappropriate induction of inflammatory responses is involved, triggered by the innate immune system. As part of its mechanism of activation, the innate immune system employs germ-lined encoded receptors, called pattern recognition receptors (PRRs in order to "sense" pathogens. One such family of PRRs are the Toll like receptor family (TLR. In the current study we aimed to elucidate the role of TLRs in Ureaplasma-induced inflammation in human amniotic epithelial cells. Using silencing, as well as human embryonic kidney (HEK transfected cell lines, we demonstrate that TLR2, TLR6 and TLR9 are involved in the inflammatory responses against Ureaplasma parvum and urealyticum serovars. Ureaplasma lipoproteins, such as Multiple Banded antigen (MBA, trigger responses via TLR2/TLR6, whereas the whole bacterium is required for TLR9 activation. No major differences were observed between the different serovars. Cell activation by Ureaplasma parvum and urealyticum seem to require lipid raft function and formation of heterotypic receptor complexes comprising of TLR2 and TLR6 on the cell surface and TLR9 intracellularly.

  5. Multifaceted effects of synthetic TLR2 ligand and Legionella pneumophilia on Treg-mediated suppression of T cell activation

    Directory of Open Access Journals (Sweden)

    Sutmuller Roger PM

    2011-03-01

    Full Text Available Abstract Background Regulatory T cells (Treg play a crucial role in maintaining immune homeostasis and self-tolerance. The immune suppressive effects of Tregs should however be limited in case effective immunity is required against pathogens or cancer cells. We previously found that the Toll-like receptor 2 (TLR2 agonist, Pam3CysSK4, directly stimulated Tregs to expand and temporarily abrogate their suppressive capabilities. In this study, we evaluate the effect of Pam3CysSK4 and Legionella pneumophila, a natural TLR2 containing infectious agent, on effector T (Teff cells and dendritic cells (DCs individually and in co-cultures with Tregs. Results TLR2 agonists can directly provide a co-stimulatory signal inducing enhanced proliferation and cytokine production of naive CD4+ Teff cells. With respect to cytokine production, DCs appear to be most sensitive to low amounts of TLR agonists. Using wild type and TLR2-deficient cells in Treg suppression assays, we accordingly show that all cells (e.g. Treg, Teff cells and DCs contributed to overcome Treg-mediated suppression of Teff cell proliferation. Furthermore, while TLR2-stimulated Tregs readily lost their ability to suppress Teff cell proliferation, cytokine production by Teff cells was still suppressed. Similar results were obtained upon stimulation with TLR2 ligand containing bacteria, Legionella pneumophila. Conclusions These findings indicate that both synthetic and natural TLR2 agonists affect DCs, Teff cells and Treg directly, resulting in multi-modal modulation of Treg-mediated suppression of Teff cells. Moreover, Treg-mediated suppression of Teff cell proliferation is functionally distinct from suppression of cytokine secretion.

  6. Dexmedetomidine Inhibits Inflammatory Reaction in Lung Tissues of Septic Rats by Suppressing TLR4/NF-κB Pathway

    Directory of Open Access Journals (Sweden)

    Yuqing Wu

    2013-01-01

    and 20 μg/kg significantly decreased mortality and pulmonary inflammation of septic rats, as well as suppressed CLP-induced elevation of TNF-α and IL-6 and inhibited TLR4/MyD88 expression and NF-κB activation. These results suggest that dexmedetomidine may decrease mortality and inhibit inflammatory reaction in lung tissues of septic rats by suppressing TLR4/MyD88/NF-κB pathway.

  7. Characterization of Innate Responses Induced by PLGA Encapsulated- and Soluble TLR Ligands In Vitro and In Vivo in Chickens.

    Directory of Open Access Journals (Sweden)

    Tamiru N Alkie

    Full Text Available Natural or synthetic Toll-like receptor (TLR ligands trigger innate responses by interacting with distinct TLRs. TLR ligands can thus serve as vaccine adjuvants or stand-alone antimicrobial agents. One of the limitations of TLR ligands for clinical application is their short half-life and rapid clearance from the body. In the current study, encapsulation of selected TLR ligands in biodegradable poly(D,L-lactide-co-glycolide polymer nanoparticles (PLGA NPs was examined in vitro and in vivo as a means to prolong innate responses. MQ-NCSU cells (a chicken macrophage cell line were treated with encapsulated or soluble forms of TLR ligands and the resulting innate responses were evaluated. In most cases, encapsulated forms of TLR ligands (CpG ODN 2007, lipopolysaccharide and Pam3CSK4 induced comparable or higher levels of nitric oxide and cytokine gene expression in macrophages, compared to the soluble forms. Encapsulated CpG ODN, in particular the higher dose, induced significantly higher expression of interferon (IFN-γ and IFN-β until at least 18 hr post-treatment. Cytokine expression by splenocytes was also examined in chickens receiving encapsulated or soluble forms of lipopolysaccharide (a potent inflammatory cytokine inducer in chickens by intramuscular injection. Encapsulated LPS induced more sustained innate responses characterized by higher expression of IFN-γ and IL-1β until up to 96 hr. The ability of TLR ligands encapsulated in polymeric nanoparticles to maintain prolonged innate responses indicates that this controlled-release system can extend the use of TLR ligands as vaccine adjuvants or as stand-alone prophylactic agents against pathogens.

  8. ST2 negatively regulates TLR2 signaling, but is not required for bacterial lipoprotein-induced tolerance.

    LENUS (Irish Health Repository)

    Liu, Jinghua

    2010-05-15

    Activation of TLR signaling is critical for host innate immunity against bacterial infection. Previous studies reported that the ST2 receptor, a member of the Toll\\/IL-1 receptor superfamily, functions as a negative regulator of TLR4 signaling and maintains LPS tolerance. However, it is undetermined whether ST2 negatively regulates TLR2 signaling and furthermore, whether a TLR2 agonist, bacterial lipoprotein (BLP)-induced tolerance is dependent on ST2. In this study, we show that BLP stimulation-induced production of proinflammatory cytokines and immunocomplex formation of TLR2-MyD88 and MyD88-IL-1R-associated kinase (IRAK) were significantly enhanced in ST2-deficient macrophages compared with those in wild-type controls. Furthermore, overexpression of ST2 dose-dependently attenuated BLP-induced NF-kappaB activation, suggesting a negative regulatory role of ST2 in TLR2 signaling. A moderate but significantly attenuated production of TNF-alpha and IL-6 on a second BLP stimulation was observed in BLP-pretreated, ST2-deficient macrophages, which is associated with substantially reduced IRAK-1 protein expression and downregulated TLR2-MyD88 and MyD88-IRAK immunocomplex formation. ST2-deficient mice, when pretreated with a nonlethal dose of BLP, benefitted from an improved survival against a subsequent lethal BLP challenge, indicating BLP tolerance develops in the absence of the ST2 receptor. Taken together, our results demonstrate that ST2 acts as a negative regulator of TLR2 signaling, but is not required for BLP-induced tolerance.

  9. Upregulated TLR3 Promotes Neuropathic Pain by Regulating Autophagy in Rat With L5 Spinal Nerve Ligation Model.

    Science.gov (United States)

    Chen, Weijia; Lu, Zhijun

    2017-02-01

    Microglia, rapidly activated following peripheral nerve injury (PNI), accumulate within the spinal cord and adopt inflammation that contributes to development and maintenance of neuropathic pain. Microglia express functional Toll-like receptors (TLRs), which play pivotal roles in regulating inflammatory processes. However, little is known about the role of TLR3 in regulating neuropathic pain after PNI. Here TLR3 expression and autophagy activation was assayed in dorsal root ganglions and in microglia following PNI by using realtime PCR, western blot and immunohistochemistry. The role of TLR3/autophagy signaling in regulating tactile allodynia was evaluated by assaying paw mechanical withdrawal threshold and cold allodynia after intrathecal administration of Poly (I:C) and 3-methyladenine (3-MA). We found that L5 spinal nerve ligation (SNL) induces the expression of TLR3 in dorsal root ganglions and in primary rat microglia at the mRNA and protein level. Meanwhile, L5 SNL results in an increased activation of autophagy, which contributes to microglial activation and subsequent inflammatory response. Intrathecal administration of Poly (I:C), a TLR3 agonist, significantly increases the activation of microglial autophagy, whereas TLR3 knockdown markedly inhibits L5 SNL-induced microglial autophagy. Poly (I:C) treatment promotes the expression of proinflammatory mediators, whereas 3-MA (a specific inhibitor of autophagy) suppresses Poly (I:C)-induced secretion of proinflammatory cytokines. Autophagy inhibition further inhibits TLR3-mediated mechanical and cold hypersensitivity following SNL. These results suggest that inhibition of TLR3/autophagy signaling contributes to alleviate neurophathic pain triggered by SNL.

  10. Trauma hemorrhagic shock-induced lung injury involves a gut-lymph-induced TLR4 pathway in mice.

    Directory of Open Access Journals (Sweden)

    Diego C Reino

    Full Text Available Injurious non-microbial factors released from the stressed gut during shocked states contribute to the development of acute lung injury (ALI and multiple organ dysfunction syndrome (MODS. Since Toll-like receptors (TLR act as sensors of tissue injury as well as microbial invasion and TLR4 signaling occurs in both sepsis and noninfectious models of ischemia/reperfusion (I/R injury, we hypothesized that factors in the intestinal mesenteric lymph after trauma hemorrhagic shock (T/HS mediate gut-induced lung injury via TLR4 activation.The concept that factors in T/HS lymph exiting the gut recreates ALI is evidenced by our findings that the infusion of porcine lymph, collected from animals subjected to global T/HS injury, into naïve wildtype (WT mice induced lung injury. Using C3H/HeJ mice that harbor a TLR4 mutation, we found that TLR4 activation was necessary for the development of T/HS porcine lymph-induced lung injury as determined by Evan's blue dye (EBD lung permeability and myeloperoxidase (MPO levels as well as the induction of the injurious pulmonary iNOS response. TRIF and Myd88 deficiency fully and partially attenuated T/HS lymph-induced increases in lung permeability respectively. Additional studies in TLR2 deficient mice showed that TLR2 activation was not involved in the pathology of T/HS lymph-induced lung injury. Lastly, the lymph samples were devoid of bacteria, endotoxin and bacterial DNA and passage of lymph through an endotoxin removal column did not abrogate the ability of T/HS lymph to cause lung injury in naïve mice.Our findings suggest that non-microbial factors in the intestinal mesenteric lymph after T/HS are capable of recreating T/HS-induced lung injury via TLR4 activation.

  11. Role of TLR4 in the Modulation of Central Amygdala GABA Transmission by CRF Following Restraint Stress.

    Science.gov (United States)

    Varodayan, F P; Khom, S; Patel, R R; Steinman, M Q; Hedges, D M; Oleata, C S; Homanics, G E; Roberto, M; Bajo, M

    2018-01-04

    Stress induces neuroimmune responses via Toll-like receptor 4 (TLR4) activation. Here, we investigated the role of TLR4 in the effects of the stress peptide corticotropin-releasing factor (CRF) on GABAergic transmission in the central nucleus of the amygdala (CeA) following restraint stress. Tlr4 knock out (KO) and wild-type rats were exposed to no stress (naïve), a single restraint stress (1 h) or repeated restraint stress (1 h per day for 3 consecutive days). After 1 h recovery from the final stress session, whole-cell patch-clamp electrophysiology was used to investigate the effects of CRF (200 nM) on CeA GABAA-mediated spontaneous inhibitory postsynaptic currents (sIPSCs). TLR4 does not regulate baseline GABAergic transmission in the CeA of naive and stress-treated animals. However, CRF significantly increased the mean sIPSC frequencies (indicating enhanced GABA release) across all genotypes and stress treatments, except for the Tlr4 KO rats that experienced repeated restraint stress. Overall, our results suggest a limited role for TLR4 in CRF's modulation of CeA GABAergic synapses in naïve and single stress rats, though TLR4-deficient rats that experienced repeated psychological stress exhibit a blunted CRF cellular response. TLR4 has a limited role in CRF's activation of the CeA under basal conditions, but interacts with the CRF system to regulate GABAergic synapse function in animals that experience repeated psychological stress. © The Author(s) 2018. Medical Council on Alcohol and Oxford University Press. All rights reserved.

  12. Functional effects of Toll-like receptor (TLR3, 7, 9, RIG-I and MDA-5 stimulation in nasal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Lotta Tengroth

    Full Text Available The human nasal epithelium is an important physical barrier, and a part of the innate immune defense that protect against pathogens. The epithelial cells recognize microbial components by pattern-recognition receptors (PRRs, and thereby trigger an immune response. Even though TLR3, TLR7, TLR9, RIG-I and MDA-5 are all known to respond to viral stimulation, their potential role in chronic airway inflammation triggered by local cytokine release remains to be established.mRNA and corresponding protein expression of TLR3, TLR7, TLR9, RIG-I and MDA-5 were analyzed in nasal biopsies and various upper airway epithelial cell lines using real-time reverse transcription PCR, immunohistochemistry and flow cytometry. Ligand induced, cytokine release, was evaluated with ELISA.Nasal biopsies were found to express TLR3, TLR7, TLR9, RIG-I and MDA-5, with the most abundant expression in the surface epithelium. These receptors were verified in primary human nasal epithelial cell (HNEC as well as in the airway epithelial cell lines Detroit-562 and FaDu. Poly(I:C (TLR3 and R-837 (TLR7 stimulation increased secretion of IL-6 and GM-CSF from the nasal mucosa and the epithelial cell lines. CpG (TLR9 stimulation caused release of IL-8 in the nasal mucosa and in FaDu. Poly(I:C/LyoVec (RIG-I/MDA-5 stimulation activated the secretion of IFN-β in the nasal mucosa. A corresponding release was also detected from HNEC and Detroit-562.The nasal epithelium has the ability to recognize viral intrusion through TLR and RLR receptors, and the subsequent response might have a role in exacerbation of inflammatory diseases like allergic rhinitis and chronic rhinosinusitis.

  13. Shielding evaluation of the Thorium Lean Raffinate (TLR) waste treatment system at Waste Immobilisation Plant, Trombay

    International Nuclear Information System (INIS)

    Bhosale, Nitin A.; Deepa, A.K.; Jakhete, A.P.; Gopalakrishnan, R.K.; Prasad, S.K.; Gangadharan, Anand; Singh, Neelima

    2012-01-01

    Thoria rods irradiated in research reactors were reprocessed for 233 U recovery and resulted in 9 m 3 of acidic Th-bearing raffinate waste. A two step treatment system was planned to treat the raffinate waste. The first step was the generation of thorium lean raffinate waste (TLR) after separation of thorium and the second step was the separation of residual radioactivity and conditioning planned at WIP. The beta activity in the TLR waste is around 50 mCi/i having 137 Cs, 90 Sr and 125 Sb as its main constituents. Shielding calculations were carried out for the various stages of the treatment system at Area-61 of WIP, Trombay. Dose rate evaluations at each step of the treatment system were evaluated to keep the personnel exposure during campaign, ALARA. The work set the base for the shielding design of the treatment system and for the estimation of the man-rem budgeting during commissioning of the system

  14. CD200R1 supports HSV-1 viral replication and licenses pro-inflammatory signaling functions of TLR2.

    Directory of Open Access Journals (Sweden)

    Roy J Soberman

    Full Text Available The CD200R1:CD200 axis is traditionally considered to limit tissue inflammation by down-regulating pro-inflammatory signaling in myeloid cells bearing the receptor. We generated CD200R1(-/- mice and employed them to explore both the role of CD200R1 in regulating macrophage signaling via TLR2 as well as the host response to an in vivo, TLR2-dependent model, herpes simplex virus 1 (HSV-1 infection. CD200R1(-/- peritoneal macrophages demonstrated a 70-75% decrease in the generation of IL-6 and CCL5 (Rantes in response to the TLR2 agonist Pam(2CSK(4 and to HSV-1. CD200R1(-/- macrophages could neither up-regulate the expression of TLR2, nor assemble a functional inflammasome in response to HSV-1. CD200R1(-/- mice were protected from HSV-1 infection and exhibited dysfunctional TLR2 signaling. Finally, both CD200R1(-/- mice and CD200R1(-/- fibroblasts and macrophages showed a markedly reduced ability to support HSV-1 replication. In summary, our data demonstrate an unanticipated and novel requirement for CD200R1 in "licensing" pro-inflammatory functions of TLR2 and in limiting viral replication that are supported by ex vivo and in vivo evidence.

  15. Effects of CPG ODN on biological behavior of PANC-1 and expression of TLR9 in pancreatic cancer.

    Science.gov (United States)

    Wu, Han-Qing; Wang, Bo; Zhu, Shi-Kai; Tian, Yuan; Zhang, Jing-Hui; Wu, He-Shui

    2011-02-28

    To determine the expression of toll-like receptor 9 (TLR9) in pancreatic tumor and the effects of cytosine phosphate-guanosine oligodeoxynucleotides 2216 (CPG ODN2216) on biological behavior of pancreatic carcinoma cell line PANC-1 and explore their clinical significance. The immunohistochemistry and Western blot were used to determine the expression of TLR9 protein in pancreatic cancer tissues, and immunofluorescence staining was performed to detect the TLR9 protein expression in pancreatic carcinoma cell line PANC-1. To assess the effects of CPG ODN2216 on the invasive property of Panc-1 cells, in vitro cell adhesion, wound-healing scrape, and invasion and cell colony formation were evaluated. TLR9 was highly expressed in pancreatic cancer tissues and PANC-1 cells. The percentage of positive cells expressing TLR9 protein in human pancreatic tissues, paracancerous tissues and normal tissues were 73.3%, 33.3% and 20.0%, respectively, and the protein expression level of TLR9 was gradually descending (P PANC-1 cells in CPG ODN 2216 treatment group were significantly lower than in the control group (P PANC-1 cells in treatment group was significantly decreased and CPG ODN2216 had an inhibitive effect in the growth of Panc-1 cells in a dose and time-dependent manner (P Panc-1 cells.

  16. DNase Sda1 allows invasive M1T1 Group A Streptococcus to prevent TLR9-dependent recognition.

    Directory of Open Access Journals (Sweden)

    Satoshi Uchiyama

    Full Text Available Group A Streptococcus (GAS has developed a broad arsenal of virulence factors that serve to circumvent host defense mechanisms. The virulence factor DNase Sda1 of the hyperinvasive M1T1 GAS clone degrades DNA-based neutrophil extracellular traps allowing GAS to escape extracellular killing. TLR9 is activated by unmethylated CpG-rich bacterial DNA and enhances innate immune resistance. We hypothesized that Sda1 degradation of bacterial DNA could alter TLR9-mediated recognition of GAS by host innate immune cells. We tested this hypothesis using a dual approach: loss and gain of function of DNase in isogenic GAS strains and presence and absence of TLR9 in the host. Either DNA degradation by Sda1 or host deficiency of TLR9 prevented GAS induced IFN-α and TNF-α secretion from murine macrophages and contributed to bacterial survival. Similarly, in a murine necrotizing fasciitis model, IFN-α and TNF-α levels were significantly decreased in wild type mice infected with GAS expressing Sda1, whereas no such Sda1-dependent effect was seen in a TLR9-deficient background. Thus GAS Sda1 suppressed both the TLR9-mediated innate immune response and macrophage bactericidal activity. Our results demonstrate a novel mechanism of bacterial innate immune evasion based on autodegradation of CpG-rich DNA by a bacterial DNase.

  17. Th2 Regulation of Viral Myocarditis in Mice: Different Roles for TLR3 versus TRIF in Progression to Chronic Disease

    Directory of Open Access Journals (Sweden)

    Eric D. Abston

    2012-01-01

    Full Text Available Viral infections are able to induce autoimmune inflammation in the heart. Here, we investigated the role of virus-activated Toll-like receptor (TLR3 and its adaptor TRIF on the development of autoimmune coxsackievirus B3 (CVB3 myocarditis in mice. Although TLR3- or TRIF-deficient mice developed similarly worse acute CVB3 myocarditis and viral replication compared to control mice, disease was significantly worse in TRIF compared to TLR3-deficient mice. Interestingly, TLR3-deficient mice developed an interleukin (IL-4-dominant T helper (Th2 response during acute CVB3 myocarditis with elevated markers of alternative activation, while TRIF-deficient mice elevated the Th2-associated cytokine IL-33. Treatment of TLR3-deficient mice with recombinant IL-33 improved heart function indicating that elevated IL-33 in the context of a classic Th2-driven response protects against autoimmune heart disease. We show for the first time that TLR3 versus TRIF deficiency results in different Th2 responses that uniquely influence the progression to chronic myocarditis.

  18. Platelet-activating factor induces TLR4 expression in intestinal epithelial cells: implication for the pathogenesis of necrotizing enterocolitis.

    Directory of Open Access Journals (Sweden)

    Antoine Soliman

    Full Text Available Necrotizing enterocolitis (NEC is a leading cause of morbidity and mortality in neonatal intensive care units, however its pathogenesis is not completely understood. We have previously shown that platelet activating factor (PAF, bacteria and TLR4 are all important factors in the development of NEC. Given that Toll-like receptors (TLRs are expressed at low levels in enterocytes of the mature gastrointestinal tract, but were shown to be aberrantly over-expressed in enterocytes in experimental NEC, we examined the regulation of TLR4 expression and signaling by PAF in intestinal epithelial cells using human and mouse in vitro cell lines, and the ex vivo rat intestinal loop model. In intestinal epithelial cell (IEC lines, PAF stimulation yielded upregulation of both TLR4 mRNA and protein expression and led to increased IL-8 secretion following stimulation with LPS (in an otherwise LPS minimally responsive cell line. PAF stimulation resulted in increased human TLR4 promoter activation in a dose dependent manner. Western blotting and immunohistochemical analysis showed PAF induced STAT3 phosphorylation and nuclear translocation in IEC, and PAF-induced TLR4 expression was inhibited by STAT3 and NFκB Inhibitors. Our findings provide evidence for a mechanism by which PAF augments inflammation in the intestinal epithelium through abnormal TLR4 upregulation, thereby contributing to the intestinal injury of NEC.

  19. Molecular Mechanisms That Underlie the Dynamic Adaptation of Innate Monocyte Memory to Varying Stimulant Strength of TLR Ligands.

    Science.gov (United States)

    Yuan, Ruoxi; Geng, Shuo; Li, Liwu

    2016-01-01

    In adaptation to rising stimulant strength, innate monocytes can be dynamically programed to preferentially express either pro- or anti-inflammatory mediators. Such dynamic innate adaptation or programing may bear profound relevance in host health and disease. However, molecular mechanisms that govern innate adaptation to varying strength of stimulants are not well understood. Using lipopolysaccharide (LPS), the model stimulant of toll-like-receptor 4 (TLR4), we reported that the expressions of pro-inflammatory mediators are preferentially sustained in monocytes adapted by lower doses of LPS, and suppressed/tolerized in monocytes adapted by higher doses of LPS. Mechanistically, monocytes adapted by super-low dose LPS exhibited higher levels of transcription factor, interferon regulatory factor 5 (IRF5), and reduced levels of transcriptional modulator B lymphocyte-induced maturation protein-1 (Blimp-1). Intriguingly, the inflammatory monocyte adaptation by super-low dose LPS is dependent upon TRAM/TRIF but not MyD88. Similar to LPS, we also observed biphasic inflammatory adaptation and tolerance in monocytes challenged with varying dosages of TLR7 agonist. In sharp contrast, rising doses of TLR3 agonist preferentially caused inflammatory adaptation without inducing tolerance. At the molecular level, the differential regulation of IRF5 and Blimp-1 coincides with unique monocyte adaptation dynamics by TLR4/7 and TLR3 agonists. Our study provides novel clue toward the understanding of monocyte adaptation and memory toward distinct TLR ligands.

  20. Molecular mechanisms that underlie the dynamic adaptation of innate monocyte memory to varying stimulant strength of TLR ligands

    Directory of Open Access Journals (Sweden)

    Ruoxi Yuan

    2016-11-01

    Full Text Available In adaptation to rising stimulant strength, innate monocytes can be dynamically programmed to preferentially express either pro- or anti-inflammatory mediators. Such dynamic innate adaptation or programming may bear profound relevance in host health and disease. However, molecular mechanisms that govern innate adaptation to varying strength of stimulants are not well understood. Using lipopolysaccharide (LPS, the model stimulant of Toll-Like-Receptor 4 (TLR4, we reported that the expressions of pro-inflammatory mediators are preferentially sustained in monocytes adapted by lower doses of LPS, and suppressed/tolerized in monocytes adapted by higher doses of LPS. Mechanistically, monocytes adapted by super-low dose LPS exhibited higher levels of transcription factor IRF5 and reduced levels of transcriptional modulator BLIMP-1. Intriguingly, the inflammatory monocyte adaptation by super-low dose LPS is dependent upon TRAM/TRIF but not MyD88. Similar to LPS, we also observed biphasic inflammatory adaptation and tolerance in monocytes challenged with varying dosages of TLR7 agonist. In sharp contrast, rising doses of TLR3 agonist preferentially caused inflammatory adaptation without inducing tolerance. At the molecular level, the differential regulation of IRF5 and Blimp-1 coincides with unique monocyte adaptation dynamics by TLR4/7 and TLR3 agonists. Our study provides novel clue toward the understanding of monocyte adaptation and memory toward distinct TLR ligands.

  1. TOLL-LIKE RECEPTORS (TLR 2 AND 4 EXPRESSION OF KERATINOCYTES FROM PATIENTS WITH LOCALIZED AND DISSEMINATED DERMATOPHYTOSIS

    Directory of Open Access Journals (Sweden)

    Cristiane Beatriz de Oliveira

    2015-02-01

    Full Text Available There are few studies on the role of innate immune response in dermatophytosis. An investigation was conducted to define the involvement of Toll-Like Receptors (TLRs 2 and 4 in localized (LD and disseminated (DD dermatophytosis due to T. rubrum. Fifteen newly diagnosed patients, eight patients with LD and seven with DD, defined by involvement of at least three body segments were used in this study. Controls comprised twenty skin samples from healthy individuals undergoing plastic surgery. TLR2 and TLR4 were quantified in skin lesions by immunohistochemistry. A reduced expression of TLR4 in the lower and upper epidermis of both LD and DD patients was found compared to controls; TLR2 expression was preserved in the upper and lower epidermis of all three groups. As TLR4 signaling induces the production of inflammatory cytokines and neutrophils recruitment, its reduced expression likely contributed to the lack of resolution of the infection and the consequent chronic nature of the dermatophytosis. As TLR2 expression acts to limit the inflammatory process and preserves the epidermal structure, its preserved expression may also contribute to the persistent infection and limited inflammation that are characteristic of dermatophytic infections.

  2. Molecular characterization and expression profile of partial TLR4 gene in association to mastitis in crossbred cattle.

    Science.gov (United States)

    Panigrahi, Manjit; Sharma, Arjava; Bhushan, Bharat

    2014-01-01

    Crossbred cattle are more prone to mastitis in comparison to indigenous cattle. Toll-like receptor 4 (TLR4) recognizes pathogen ligands, for example, lipopolysaccharide (LPS) endotoxin from Escherichia coli and mediates signaling to initiate innate and adaptive immune responses. Mutations in TLR4 can compromise the host immune response to certain pathogens, so it may be a potential candidate for marker assisted selection to enhance mastitis resistance in dairy cattle. Hence, in this study role of bovine TLR4 gene in mastitis resistance was investigated by association as well as expression profiling analysis in crossbred cattle. The animals were divided into mastitis affected and unaffected groups on the basis of history of animals and California Mastitis Test (CMT). PCR-SSCP and Sequence analysis revealed three genotypes of coreceptor binding region 1 (CRBR1) fragment of TLR4 gene namely AA, AB, and BB in both groups of cattle. The logistic regression model did not show any significant effect of these genotypes on the occurrence of clinical mastitis. Moreover, in vitro challenge of peripheral blood mononuclear cells (PBMCs) with LPS failed to show any association of the genotypes with TLR4 gene expression. In a nutshell, in the present study enough evidence was not found for association of the SNP variants of CRBR1 fragment of TLR4 gene with mastitis susceptibility in crossbred cattle.

  3. Staphylococcus epidermidis polysaccharide intercellular adhesin induces IL-8 expression in human astrocytes via a mechanism involving TLR2.

    LENUS (Irish Health Repository)

    Stevens, Niall T

    2009-03-01

    Staphylococcus epidermidis is an opportunistic biofilm-forming pathogen associated with neurosurgical device-related meningitis. Expression of the polysaccharide intercellular adhesin (PIA) on its surface promotes S. epidermidis biofilm formation. Here we investigated the pro-inflammatory properties of PIA against primary and transformed human astrocytes. PIA induced IL-8 expression in a dose- and\\/or time-dependent manner from U373 MG cells and primary normal human astrocytes. This effect was inhibited by depletion of N-acetyl-beta-d-glucosamine polymer from the PIA preparation with Lycopersicon esculentum lectin or sodium meta-periodate. Expression of dominant-negative versions of the TLR2 and TLR4 adaptor proteins MyD88 and Mal in U373 MG cells inhibited PIA-induced IL-8 production. Blocking IL-1 had no effect. PIA failed to induce IL-8 production from HEK293 cells stably expressing TLR4. However, in U373 MG cells which express TLR2, neutralization of TLR2 impaired PIA-induced IL-8 production. In addition to IL-8, PIA also induced expression of other cytokines from U373 MG cells including IL-6 and MCP-1. These data implicate PIA as an important immunogenic component of the S. epidermidis biofilm that can regulate pro-inflammatory cytokine production from human astrocytes, in part, via TLR2.

  4. Disruption of TLR3 signaling due to cleavage of TRIF by the hepatitis A virus protease-polymerase processing intermediate, 3CD.

    Directory of Open Access Journals (Sweden)

    Lin Qu

    2011-09-01

    Full Text Available Toll-like receptor 3 (TLR3 and cytosolic RIG-I-like helicases (RIG-I and MDA5 sense viral RNAs and activate innate immune signaling pathways that induce expression of interferon (IFN through specific adaptor proteins, TIR domain-containing adaptor inducing interferon-β (TRIF, and mitochondrial antiviral signaling protein (MAVS, respectively. Previously, we demonstrated that hepatitis A virus (HAV, a unique hepatotropic human picornavirus, disrupts RIG-I/MDA5 signaling by targeting MAVS for cleavage by 3ABC, a precursor of the sole HAV protease, 3C(pro, that is derived by auto-processing of the P3 (3ABCD segment of the viral polyprotein. Here, we show that HAV also disrupts TLR3 signaling, inhibiting poly(I:C-stimulated dimerization of IFN regulatory factor 3 (IRF-3, IRF-3 translocation to the nucleus, and IFN-β promoter activation, by targeting TRIF for degradation by a distinct 3ABCD processing intermediate, the 3CD protease-polymerase precursor. TRIF is proteolytically cleaved by 3CD, but not by the mature 3C(pro protease or the 3ABC precursor that degrades MAVS. 3CD-mediated degradation of TRIF depends on both the cysteine protease activity of 3C(pro and downstream 3D(pol sequence, but not 3D(pol polymerase activity. Cleavage occurs at two non-canonical 3C(pro recognition sequences in TRIF, and involves a hierarchical process in which primary cleavage at Gln-554 is a prerequisite for scission at Gln-190. The results of mutational studies indicate that 3D(pol sequence modulates the substrate specificity of the upstream 3C(pro protease when fused to it in cis in 3CD, allowing 3CD to target cleavage sites not normally recognized by 3C(pro. HAV thus disrupts both RIG-I/MDA5 and TLR3 signaling pathways through cleavage of essential adaptor proteins by two distinct protease precursors derived from the common 3ABCD polyprotein processing intermediate.

  5. Association Between Antibiotic Exposure, Bronchiolitis, and TLR4 (rs1927911) Polymorphisms in Childhood Asthma

    Science.gov (United States)

    Lee, Eun; Kwon, Ji-Won; Kim, Hyo-Bin; Yu, Ho-Sung; Kang, Mi-Jin; Hong, Kyungmo; Yang, Song I; Jung, Young Ho; Lee, Seung-Hwa; Choi, Kil Young; Shin, Hye Lim; Hong, Seo Ah; Kim, Hyung Young; Seo, Ju-Hee; Kim, Byoung-Ju; Lee, So Yeon; Song, Dae Jin; Kim, Woo-Kyung; Jang, Gwang Cheon; Shim, Jung Yeon

    2015-01-01

    Purpose The complex interplay between environmental and genetic factors plays an important role in the development of asthma. Several studies have yielded conflicting results regarding the 2 asthma-related risk factors: antibiotic usage during infancy and/or a history of bronchiolitis during early life and the development of asthma. In addition to these risk factors, we also explored the effects of Toll-like receptor 4 (TLR4) polymorphism on the development of childhood asthma. Methods This cross-sectional study involved 7,389 middle school students who were from 8 areas of Seoul, Korea, and completed the International Study of Asthma and Allergies in Childhood questionnaire. The TLR4 polymorphism rs1927911 was genotyped in 1,395 middle school students from two areas using the TaqMan assay. Results Bronchiolitis in the first 2 years of life, antibiotic exposure during the first year of life, and parental history of asthma were independent risk factors for the development of asthma. When combined, antibiotic use and a history of bronchiolitis increased the risk of asthma (adjusted odds ratio [aOR]: 4.64, 95% confidence interval [CI]: 3.09-6.97, P value for interaction=0.02). In subjects with CC genotype of TLR4, antibiotic exposure and a history of bronchiolitis during infancy, the risk of asthma was increased, compared to subjects without these risk factors (aOR: 5.72, 95% CI: 1.74-18.87). Conclusions Early-life antibiotic exposures and a history of bronchiolitis are risk factors for asthma in young adolescents. Polymorphisms of TLR4 modified the influence of these environmental factors. Reducing antibiotic exposure and preventing bronchiolitis during infancy may prevent the development of asthma, especially in genetically susceptible subjects. PMID:25729624

  6. Clinical characteristics and frequency of TLR4 polymorphisms in Brazilian patients with ankylosing spondylitis

    Directory of Open Access Journals (Sweden)

    Natalia Pereira Machado

    Full Text Available ABSTRACT Objectives: Innate immunity is involved in the physiopathology of ankylosing spondylitis (AS, with the participation of Gram-negative bacteria, modulation of human leukocyte antigen (HLA B27 and the involvement of pattern recognition receptors, such as Toll-like receptors (TLRs. The aim of this study was to investigate the clinical characteristics and frequency of TLR4 polymorphisms (Asp299Gly and Thr 399Ile in a cohort of Brazilian patients with AS. Methods: A cross-sectional study was carried out involving 200 patients with a diagnosis of AS and a healthy control group of 200 individuals. Disease activity, severity and functional capacity were measured. The study of TLR4 polymorphisms was performed using the restriction fragment length polymorphism method. HLA-B27 was analyzed by conventional polymerase chain reaction. The IBM SPSS Statistics 20 program was used for the statistical analysis, with p-values less than 0.05 considered significant. Results: Mean age and disease duration were 43.1 ± 12.7 and 16.6 ± 9.2 years, respectively. The sample was predominantly male (71% and non-Caucasian (52%. A total of 66% of the group of patients were positive for HLA-B27. The sample of patients was characterized by moderate functional impairment and a high degree of disease activity. No significant association was found between the two TLR4 polymorphisms and susceptibility to AS. Conclusions: TLR4 polymorphisms 399 and 299 were not more frequent in patients with AS in comparison to the health controls and none of the clinical variables were associated with these polymorphisms.

  7. Mechanism for radiation-induced damage via TLR3 on the intestinal epithelium

    International Nuclear Information System (INIS)

    Takemura, Naoki; Uematsu, Satoshi

    2014-01-01

    When the small-intestinal epithelium is injured due to high-dose radiation exposure, radiation-induced gastrointestinal syndrome (GIS) such as absorption inhibition and intestinal bacterial infection occurs, and lead to subacute death. The authors immunologically analyzed the disease onset mechanism of GIS. In the small-intestinal mucosal epithelium, the intestinal epithelial stem cells of crypt structure and their daughter cells are renewed through proliferation and differentiation in the cycle of 3 or 4 days. When DNA is damaged by radiation, although p53 gene stops cell cycle and repairs DNA, cell death is induced if the repair is impossible. When stem cells perish, cell supply stops resulting in epithelial breakdown and fatal GIS. The authors analyzed the involvement in GIS of toll-like receptor (TLR) with the function of natural immunity, based on lethal γ-ray irradiation on KO mice and other methods. The authors found the mechanism, in which RNA that was leaked due to cell death caused by p53 gene elicits inflammation by activating TLR3, and leads to GIS through a wide range of cell death induction and stem cell extinction. The administration of a TLR3/RNA binding inhibitor before the irradiation of mice decreased crypt cell death and greatly improved survival rate. The administration one hour after the irradiation also showed improvement. The administration of the TLR3 specific inhibitor within a fixed time after the exposure is hopeful for the prevention of GIS, without affecting the DNA repair function of p53 gene. (A.O.)

  8. (TLR) 1, 4, 9 and SLC11A1 genes and their associationwith ...

    Indian Academy of Sciences (India)

    Ulas

    suggest that selection against TLR1 (+1380 G/A) may reduce the risk of ... control strategies providing better benefit/cost ratios of more conservative strategies like .... MgCl2, 200μM dNTPs, 10 pM of forward and reverse primers and 0.5 U of Taq ... analysis for logistic regression considered the infection status as categorical ...

  9. Botulinum neurotoxin type A induces TLR2-mediated inflammatory responses in macrophages.

    Directory of Open Access Journals (Sweden)

    Yun Jeong Kim

    Full Text Available Botulinum neurotoxin type A (BoNT/A is the most potent protein toxin and causes fatal flaccid muscle paralysis by blocking neurotransmission. Application of BoNT/A has been extended to the fields of therapeutics and biodefense. Nevertheless, the global response of host immune cells to authentic BoNT/A has not been reported. Employing microarray analysis, we performed global transcriptional profiling of RAW264.7 cells, a murine alveolar macrophage cell line. We identified 70 genes that were modulated following 1 nM BoNT/A treatment. The altered genes were mainly involved in signal transduction, immunity and defense, protein metabolism and modification, neuronal activities, intracellular protein trafficking, and muscle contraction. Microarray data were validated with real-time RT-PCR for seven selected genes including tlr2, tnf, inos, ccl4, slpi, stx11, and irg1. Proinflammatory mediators such as nitric oxide (NO and tumor necrosis factor alpha (TNFα were induced in a dose-dependent manner in BoNT/A-stimulated RAW264.7 cells. Increased expression of these factors was inhibited by monoclonal anti-Toll-like receptor 2 (TLR2 and inhibitors specific to intracellular proteins such as c-Jun N-terminal kinase (JNK, extracellular signal-regulated kinase (ERK, and p38 mitogen-activated protein kinase (MAPK. BoNT/A also suppressed lipopolysaccharide-induced NO and TNFα production from RAW264.7 macrophages at the transcription level by blocking activation of JNK, ERK, and p38 MAPK. As confirmed by TLR2-/- knock out experiments, these results suggest that BoNT/A induces global gene expression changes in host immune cells and that host responses to BoNT/A proceed through a TLR2-dependent pathway, which is modulated by JNK, ERK, and p38 MAPK.

  10. Genome-wide screening identifies Plasmodium chabaudi-induced modifications of DNA methylation status of Tlr1 and Tlr6 gene promoters in liver, but not spleen, of female C57BL/6 mice.

    Science.gov (United States)

    Al-Quraishy, Saleh; Dkhil, Mohamed A; Abdel-Baki, Abdel Azeem S; Delic, Denis; Santourlidis, Simeon; Wunderlich, Frank

    2013-11-01

    Epigenetic reprogramming of host genes via DNA methylation is increasingly recognized as critical for the outcome of diverse infectious diseases, but information for malaria is not yet available. Here, we investigate the effect of blood-stage malaria of Plasmodium chabaudi on the DNA methylation status of host gene promoters on a genome-wide scale using methylated DNA immunoprecipitation and Nimblegen microarrays containing 2,000 bp oligonucleotide features that were split into -1,500 to -500 bp Ups promoters and -500 to +500 bp Cor promoters, relative to the transcription site, for evaluation of differential DNA methylation. Gene expression was analyzed by Agilent and Affymetrix microarray technology. Challenging of female C57BL/6 mice with 10(6) P. chabaudi-infected erythrocytes resulted in a self-healing outcome of infections with peak parasitemia on day 8 p.i. These infections induced organ-specific modifications of DNA methylation of gene promoters. Among the 17,354 features on Nimblegen arrays, only seven gene promoters were identified to be hypermethylated in the spleen, whereas the liver exhibited 109 hyper- and 67 hypomethylated promoters at peak parasitemia in comparison with non-infected mice. Among the identified genes with differentially methylated Cor-promoters, only the 7 genes Pigr, Ncf1, Klkb1, Emr1, Ndufb11, and Tlr6 in the liver and Apol6 in the spleen were detected to have significantly changed their expression. Remarkably, the Cor promoter of the toll-like receptor Tlr6 became hypomethylated and Tlr6 expression increased by 3.4-fold during infection. Concomitantly, the Ups promoter of the Tlr1 was hypermethylated, but Tlr1 expression also increased by 11.3-fold. TLR6 and TLR1 are known as auxillary receptors to form heterodimers with TLR2 in plasma membranes of macrophages, which recognize different pathogen-associated molecular patterns (PAMPs), as, e.g., intact 3-acyl and sn-2-lyso-acyl glycosylphosphatidylinositols of P. falciparum

  11. Morphine amplifies mechanical allodynia via TLR4 in a rat model of spinal cord injury

    Science.gov (United States)

    Ellis, Amanda; Grace, Peter M.; Wieseler, Julie; Favret, Jacob; Springer, Kendra; Skarda, Bryce; Hutchinson, Mark R.; Falci, Scott; Rice, Kenner C.; Maier, Steven F.; Watkins, Linda R.

    2016-01-01

    Central neuropathic pain (CNP) is a pervasive, debilitating problem that impacts thousands of people living with central nervous system disorders, including spinal cord injury (SCI). Current therapies for treating this type of pain are ineffective and often have dose-limiting side effects. Although opioids are one of the most commonly used CNP treatments, recent animal literature has indicated that administering opioids shortly after a traumatic injury can actually have deleterious effects on long-term health and recovery. In order to study the deleterious effects of administering morphine shortly after trauma, we employed our low thoracic (T13) dorsal root avulsion model (Spinal Neuropathic Avulsion Pain, SNAP). Administering a weeklong course of 10 mg/kg/day morphine beginning 24 hr after SNAP resulted in amplified mechanical allodynia. Co-administering the non-opioid toll-like receptor 4 (TLR4) antagonist (+)-naltrexone throughout the morphine regimen prevented morphine-induced amplification of SNAP. Exploration of changes induced by early post-trauma morphine revealed that this elevated gene expression of TLR4, TNF, IL-1β, and NLRP3, as well as IL-1β protein at the site of spinal cord injury. These data suggest that a short course of morphine administered early after spinal trauma can exacerbate CNP in the long term. TLR4 initiates this phenomenon and, as such, may be potential therapeutic targets for preventing the deleterious effects of administering opioids after traumatic injury. PMID:27519154

  12. Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Lena Seifert

    2015-12-01

    Full Text Available Dectin-1 is a C-type lectin receptor critical in anti-fungal immunity, but Dectin-1 has not been linked to regulation of sterile inflammation or oncogenesis. We found that Dectin-1 expression is upregulated in hepatic fibrosis and liver cancer. However, Dectin-1 deletion exacerbates liver fibro-inflammatory disease and accelerates hepatocarcinogenesis. Mechanistically, we found that Dectin-1 protects against chronic liver disease by suppressing TLR4 signaling in hepatic inflammatory and stellate cells. Accordingly, Dectin-1–/– mice exhibited augmented cytokine production and reduced survival in lipopolysaccharide (LPS-mediated sepsis, whereas Dectin-1 activation was protective. We showed that Dectin-1 inhibits TLR4 signaling by mitigating TLR4 and CD14 expression, which are regulated by Dectin-1-dependent macrophage colony stimulating factor (M-CSF expression. Our study suggests that Dectin-1 is an attractive target for experimental therapeutics in hepatic fibrosis and neoplastic transformation. More broadly, our work deciphers critical cross-talk between pattern recognition receptors and implicates a role for Dectin-1 in suppression of sterile inflammation, inflammation-induced oncogenesis, and LPS-mediated sepsis.

  13. Dectin-1 Regulates Hepatic Fibrosis and Hepatocarcinogenesis by Suppressing TLR4 Signaling Pathways.

    Science.gov (United States)

    Seifert, Lena; Deutsch, Michael; Alothman, Sara; Alqunaibit, Dalia; Werba, Gregor; Pansari, Mridul; Pergamo, Matthew; Ochi, Atsuo; Torres-Hernandez, Alejandro; Levie, Elliot; Tippens, Daniel; Greco, Stephanie H; Tiwari, Shaun; Ly, Nancy Ngoc Giao; Eisenthal, Andrew; van Heerden, Eliza; Avanzi, Antonina; Barilla, Rocky; Zambirinis, Constantinos P; Rendon, Mauricio; Daley, Donnele; Pachter, H Leon; Hajdu, Cristina; Miller, George

    2015-12-01

    Dectin-1 is a C-type lectin receptor critical in anti-fungal immunity, but Dectin-1 has not been linked to regulation of sterile inflammation or oncogenesis. We found that Dectin-1 expression is upregulated in hepatic fibrosis and liver cancer. However, Dectin-1 deletion exacerbates liver fibro-inflammatory disease and accelerates hepatocarcinogenesis. Mechanistically, we found that Dectin-1 protects against chronic liver disease by suppressing TLR4 signaling in hepatic inflammatory and stellate cells. Accordingly, Dectin-1(-/-) mice exhibited augmented cytokine production and reduced survival in lipopolysaccharide (LPS)-mediated sepsis, whereas Dectin-1 activation was protective. We showed that Dectin-1 inhibits TLR4 signaling by mitigating TLR4 and CD14 expression, which are regulated by Dectin-1-dependent macrophage colony stimulating factor (M-CSF) expression. Our study suggests that Dectin-1 is an attractive target for experimental therapeutics in hepatic fibrosis and neoplastic transformation. More broadly, our work deciphers critical cross-talk between pattern recognition receptors and implicates a role for Dectin-1 in suppression of sterile inflammation, inflammation-induced oncogenesis, and LPS-mediated sepsis. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Pharmacological TLR4 Inhibition Protects against Acute and Chronic Fat-Induced Insulin Resistance in Rats.

    Science.gov (United States)

    Zhang, Ning; Liang, Hanyu; Farese, Robert V; Li, Ji; Musi, Nicolas; Hussey, Sophie E

    2015-01-01

    To evaluate whether pharmacological TLR4 inhibition protects against acute and chronic fat-induced insulin resistance in rats. For the acute experiment, rats received a TLR4 inhibitor [TAK-242 or E5564 (2x5 mg/kg i.v. bolus)] or vehicle, and an 8-h Intralipid (20%, 8.5 mg/kg/min) or saline infusion, followed by a two-step hyperinsulinemic-euglycemic clamp. For the chronic experiment, rats were subcutaneously implanted with a slow-release pellet of TAK-242 (1.5 mg/d) or placebo. Rats then received a high fat diet (HFD) or a low fat control diet (LFD) for 10 weeks, followed by a two-step insulin clamp. Acute experiment; the lipid-induced reduction (18%) in insulin-stimulated glucose disposal (Rd) was attenuated by TAK-242 and E5564 (the effect of E5564 was more robust), suggesting improved peripheral insulin action. Insulin was able to suppress hepatic glucose production (HGP) in saline- but not lipid-treated rats. TAK-242, but not E5564, partially restored this effect, suggesting improved HGP. Chronic experiment; insulin-stimulated Rd was reduced ~30% by the HFD, but completely restored by TAK-242. Insulin could not suppress HGP in rats fed a HFD and TAK-242 had no effect on HGP. Pharmacological TLR4 inhibition provides partial protection against acute and chronic fat-induced insulin resistance in vivo.

  15. Mycobacterial Phenolic Glycolipids Selectively Disable TRIF-Dependent TLR4 Signaling in Macrophages

    Directory of Open Access Journals (Sweden)

    Reid Oldenburg

    2018-01-01

    Full Text Available Phenolic glycolipids (PGLs are cell wall components of a subset of pathogenic mycobacteria, with immunomodulatory properties. Here, we show that in addition, PGLs exert antibactericidal activity by limiting the production of nitric oxide synthase (iNOS in mycobacteria-infected macrophages. PGL-mediated downregulation of iNOS was complement receptor 3-dependent and comparably induced by bacterial and purified PGLs. Using Mycobacterium leprae PGL-1 as a model, we found that PGLs dampen the toll-like receptor (TLR4 signaling pathway, with macrophage exposure to PGLs leading to significant reduction in TIR-domain-containing adapter-inducing interferon-β (TRIF protein level. PGL-driven decrease in TRIF operated posttranscriptionally and independently of Src-family tyrosine kinases, lysosomal and proteasomal degradation. It resulted in the defective production of TRIF-dependent IFN-β and CXCL10 in TLR4-stimulated macrophages, in addition to iNOS. Our results unravel a mechanism by which PGLs hijack both the bactericidal and inflammatory responses of host macrophages. Moreover, they identify TRIF as a critical node in the crosstalk between CR3 and TLR4.

  16. The scavenger receptor MARCO modulates TLR-induced responses in dendritic cells.

    Directory of Open Access Journals (Sweden)

    Haydn T Kissick

    Full Text Available The scavenger receptor MARCO mediates macrophage recognition and clearance of pathogens and their polyanionic ligands. However, recent studies demonstrate MARCO expression and function in dendritic cells, suggesting MARCO might serve to bridge innate and adaptive immunity. To gain additional insight into the role of MARCO in dendritic cell activation and function, we profiled transcriptomes of mouse splenic dendritic cells obtained from MARCO deficient mice and their wild type counterparts under resting and activating conditions. In silico analysis uncovered major alterations in gene expression in MARCO deficient dendritic cells resulting in dramatic alterations in key dendritic cell-specific pathways and functions. Specifically, changes in CD209, FCGR4 and Complement factors can have major consequences on DC-mediated innate responses. Notably, these perturbations were magnified following activation with the TLR-4 agonist lipopolysaccharide. To validate our in silico data, we challenged DC's with various agonists that recognize all mouse TLRs and assessed expression of a set of immune and inflammatory marker genes. This approach identified a differential contribution of MARCO to TLR activation and validated a major role for MARCO in mounting an inflammatory response. Together, our data demonstrate that MARCO differentially affects TLR-induced DC activation and suggest targeting of MARCO could lead to different outcomes that depend on the inflammatory context encountered by DC.

  17. Basophils activated via TLR signaling may contribute to pathophysiology of type 1 autoimmune pancreatitis.

    Science.gov (United States)

    Yanagawa, Masato; Uchida, Kazushige; Ando, Yugo; Tomiyama, Takashi; Yamaguchi, Takashi; Ikeura, Tsukasa; Fukui, Toshiro; Nishio, Akiyoshi; Uemura, Yoshiko; Miyara, Takayuki; Okamoto, Hiroyuki; Satoi, Souhei; Okazaki, Kazuichi

    2018-03-01

    Pathophysiology of type 1 autoimmune pancreatitis (AIP) is still unclear. We previously reported that M2 macrophages might play an important role in type 1 AIP. Recently, it has been reported that basophils regulate differentiation to M2 macrophages. In this study, we investigated basophils from the pancreatic tissue and peripheral blood of individuals with type 1 AIP. By using immunohistochemistry, we investigated basophils in pancreatic tissue from 13 patients with type 1 AIP and examined expression of toll-like receptors (TLRs) by these cells. Additionally, we obtained peripheral blood samples from 27 healthy subjects, 40 patients with type 1 AIP, 8 patients with alcoholic chronic pancreatitis, 10 patients with bronchial asthma, and 10 patients with atopic dermatitis, and analyzed activation of basophils by stimulating them with ligands of TLR1-9. We also compared TLR expression in basophils from the tissue and blood samples. Basophils were detected in pancreatic tissues from 10 of 13 patients with type 1 AIP. Flow cytometric analysis revealed that the ratios of basophils activated by TLR4 stimulation in type 1 AIP (9.875 ± 1.148%) and atopic dermatitis (11.768 ± 1.899%) were significantly higher than those in healthy subjects (5.051 ± 0.730%; P pathophysiology of type 1 AIP.

  18. Toll-like receptor 4 (TLR4) impairs nitric oxide contributing to Angiotensin II-induced cavernosal dysfunction.

    Science.gov (United States)

    Nunes, Kenia P; Bomfim, Gisele F; Toque, Haroldo A; Szasz, Theodora; Clinton Webb, R

    2017-12-15

    Angiotensin II (AngII), a corpus cavernosum (CC) constrictor peptide, modulates Toll like receptor (TLR) expression, a key element of the innate immune system, contributing to impaired vascular function in pathological conditions. However, it is unknown whether TLR4 is involved in AngII-induced erectile dysfunction. In this study, we investigated whether TLR4 plays a role in cavernosal dysfunction caused by AngII upregulation. Cavernosal smooth muscle cells (CSMC) from C57/BL6 mice were treated with AngII (0.1μM) or bacterial LPS (50ng/ml) for 12-24h and TLR4 expression was assessed. Mice were infused with AngII (90ng/min, 28days) and treated with anti-TLR4 antibody (0.1mg/daily, i.p.) for the last 14days of the treatment. CC tissue was used for functional studies and for Western blotting. Nitric Oxide Synthase (NOS) activity was measured by conversion of [ 3 H]-l-arginine to [ 3 H]-l-citrulline, systemic TNF-α levels by ELISA, and reactive oxygen species (ROS) by immunofluorescence. We report upregulation of TLR4 in CSMC following AngII or LPS stimulation. In AngII-infused mice, chronic treatment with anti-TLR4 antibody (28±2.1%) attenuates adrenergic CC contraction, which also ameliorates nitrergic (68.90±0.21 vs. 51.07±0.63, 8Hz, AngII-infused mice treated vs. non-treated). Decreased endothelial NOS expression, reduced NOS activity, and augmented levels of TNF-α, and ROS were found following AngII-infusion. These alterations were prevented, or at least decreased by anti-TLR4 antibody treatment. Inhibition of TLR4 ameliorates AngII-impaired cavernosal relaxation, decreases TNF-α levels, and restores NO bioavailability, demonstrating that TLR4 partly mediates AngII-induced cavernosal dysfunction. Copyright © 2017. Published by Elsevier Inc.

  19. P-MAPA immunotherapy potentiates the effect of cisplatin on serous ovarian carcinoma through targeting TLR4 signaling.

    Science.gov (United States)

    de Almeida Chuffa, Luiz Gustavo; de Moura Ferreira, Grazielle; Lupi, Luiz Antonio; da Silva Nunes, Iseu; Fávaro, Wagner José

    2018-01-17

    Toll-like receptors (TLRs) are transmembrane proteins expressed on the surface of ovarian cancer (OC) and immune cells. Identifying the specific roles of the TLR-mediated signaling pathways in OC cells is important to guide new treatments. Because immunotherapies have emerged as the adjuvant treatment for patients with OC, we investigated the effect of a promising immunotherapeutic strategy based on protein aggregate magnesium-ammonium phospholinoleate-palmitoleate anhydride (P-MAPA) combined with cisplatin (CIS) on the TLR2 and TLR4 signaling pathways via myeloid differentiation factor 88 (MyD88) and TLR-associated activator of interferon (TRIF) in an in vivo model of OC. Tumors were chemically induced by a single injection of 100 μg of 7,12-dimethylbenz(a)anthracene (DMBA) directly under the left ovarian bursa in Fischer 344 rats. After the rats developed serous papillary OC, they were given P-MAPA, CIS or the combination P-MAPA+CIS as therapies. To understand the effects of the treatments, we assessed the tumor size, histopathology, and the TLR2- and TLR4-mediated inflammatory responses. Although CIS therapy was more effective than P-MAPA in reducing the tumor size, P-MAPA immunotherapy significantly increased the expressions of TLR2 and TLR4. More importantly, the combination of P-MAPA with CIS showed a greater survival rate compared to CIS alone, and exhibited a significant reduction in tumor volume compared to P-MAPA alone. The combination therapy also promoted the increase in the levels of the following OC-related proteins: TLR4, MyD88, TRIF, inhibitor of phosphorylated NF-kB alpha (p-IkBα), and nuclear factor kappa B (NF-kB p65) in both cytoplasmic and nuclear sites. While P-MAPA had no apparent effect on tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6, it seems to increase interferon-γ (IFN-γ), which may induce the Thelper (Th1)-mediated immune response. Collectively, our results suggest that P-MAPA immunotherapy combined with cisplatin

  20. Increased expression of TLR9 associated with pro-inflammatory S100A8 and IL-8 in diabetic wounds could lead to unresolved inflammation in type 2 diabetes mellitus (T2DM) cases with impaired wound healing.

    Science.gov (United States)

    Singh, Kanhaiya; Agrawal, Neeraj K; Gupta, Sanjeev K; Sinha, Pratima; Singh, Kiran

    2016-01-01

    Type 2 diabetes mellitus (T2DM) is characterized by persistent hyperglycemia which causes a chain of abrupt biochemical and physiological changes. Immune dys-regulation is the hallmark of T2DM that could contribute to prolonged inflammation causing transformation of wounds into non-healing chronic ulcers. Toll like receptor -9 (TLR9) is a major receptor involved in innate immune regulation. TLR9 activation induces release of pro-inflammatory molecules like S100A8 and interleukin-8 (IL-8) by myeloid cells causing migration of myeloid cells to the site of inflammation. We hypothesized that pro-inflammatory S100A8 and IL-8 proteins could cause persistent inflammation in chronic wounds like diabetic foot ulcer (DFU) and may contribute to impaired wound healing in T2DM patients. Expression of TLR9 and its downstream effector molecules S100A8, and IL-8 were analyzed in chronic diabetic wound and non-diabetic control wound tissue samples by semiquantitative reverse transcriptase - polymerase chain reaction (RT-PCR), quantitative RT-PCR, western blot and immunofluorescence. CD11b(+)CD33(+) myeloid cells were analyzed by flow cytometry. TLR9 message and protein were higher in diabetic wounds compared to control wounds (p=0.03, t=2.21 for TLR9 mRNA; p=diabetic wounds (p=0.003, t=3.1 for S100A8 mRNA; p=0.04, t=2.04 for IL-8). CD11b(+) CD33(+) myeloid cells were decreased in T2DM as compared to non-diabetic controls (p=0.001, t=3.6). DFU subjects had higher levels of CD11b(+) CD33(+) myeloid cells as compared to non-DFU T2DM control (p=0.003, t=2.8). Infection in the wound microenvironment could be the cause of increase in CD11b(+)CD33(+) myeloid cells in DFU (p=0.03, t=2.5). The up-regulation of myeloid cell-derived pro-inflammatory molecules S100A8 and IL-8 in combination with lower levels of CD11b(+) CD33(+) myeloid cells may cause the impairment of wound healing in T2DM subjects leading to chronic ulcers. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Bifidobacterium breve C50 secretes lipoprotein with CHAP domain recognized in aggregated form by TLR2.

    Science.gov (United States)

    Scuotto, Angelo; Djorie, Serge; Colavizza, Michel; Romond, Pierre-Charles; Romond, Marie-Bénédicte

    2014-12-01

    Extracellular components secreted by Bifidobacterium breve C50 can induce maturation, high IL-10 production and prolonged survival of dendritic cells via a TLR2 pathway. In this study, the components were isolated from the supernatant by gel filtration chromatography. Antibodies raised against the major compounds with molecular weight above 600 kDa (Bb C50BC) also recognized compounds of lower molecular weight (200–600 kDa). TLR2 and TLR6 bound to the components already recognized by the antibodies. Trypsin digestion of Bb C50BC released three major peptides whose sequences displayed close similarities to a putative secreted protein with a CHAP amidase domain from B. breve. The 1300-bp genomic region corresponding to the hypothetical protein was amplified by PCR. The deduced polypeptide started with an N-terminal signal sequence of 45 amino acids, containing the lipobox motif (LAAC) with the cysteine in position 25, and 2 positively charged residues within the first 14 residues of the signal sequence. Lipid detection in Bb C50BC by GC/MS further supported the implication of a lipoprotein. Sugars were also detected in Bb C50BC. Close similarity with the glucan-binding protein B from Bifidobacterium animalis of two released peptides from Bb C50BC protein suggested that glucose moieties, possibly in glucan form, could be bound to the lipoprotein. Finally, heating at 100 °C for 5 min led to the breakdown of Bb C50BC in compounds of molecular weight below 67 kDa, which suggested that Bb C50BC was an aggregate. One might assume that a basic unit was formed by the lipoprotein bound putatively to glucan. Besides the other sugars and hexosamines recognized by galectin 1 were localized at the surface of the Bb C50BC aggregate. In conclusion, the extracellular components secreted by B. breve C50 were constituted of a lipoprotein putatively associated with glucose moieties and acting in an aggregating form as an agonist of TLR2/TLR6.

  2. Innate immune response of alveolar macrophage to house dust mite allergen is mediated through TLR2/-4 co-activation.

    Directory of Open Access Journals (Sweden)

    Chia-Fang Liu

    Full Text Available House dust mite, Dermatophagoides pteronyssinus (Der p, is one of the major allergens responsible for allergic asthma. However, the putative receptors involved in the signalization of Der p to the innate immune cells are still poorly defined as well as the impact of their activation on the outcome of the allergen-induced cell response. We previously reported that the HDM activation of mouse alveolar macrophages (AM involves the TLR4/CD14 cell surface receptor complex. Here using a TLR ligand screening essay, we demonstrate that HDM protein extract engages the TLR2, in addition to the TLR4, in engineered TLR-transfected HEK cells but also in the MH-S mouse alveolar macrophage cell line model. Moreover we found that the concomitant recruitment of the MH-S cell's TLR2 and TLR4 receptors by the HDM extract activates the MyD88-dependent signaling pathway and leads to the secretion of the NF-κB regulated pro-inflammatory factors NO and TNF-α. However unlike with the canonical TLR4 ligand (i.e. the bacterial LPS mobilization of TLR4 by the HDM extract induces a reduced production of the IL-12 pro-inflammatory cytokine and fails to trigger the expression of the T-bet transcription factor. Finally we demonstrated that HDM extract down-regulates LPS induced IL-12 and T-bet expression through a TLR2 dependent mechanism. Therefore, we propose that the simultaneous engagement of the TLR2 and TLR4 receptors by the HDM extract results in a cross regulated original activation pattern of the AM which may contribute to the Th2 polarization of the allergen-induced immune response. The deciphering of these cross-regulation networks is of prime importance to open the way for original therapeutic strategies taking advantage of these receptors and their associated signaling pathways to treat allergic asthma.

  3. The tylosin resistance gene tlrB of Streptomyces fradiae encodes a methyltransferase that targets G748 in 23S rRNA

    DEFF Research Database (Denmark)

    Liu, M; Kirpekar, F; Van Wezel, G P

    2000-01-01

    tlrB is one of four resistance genes encoded in the operon for biosynthesis of the macrolide tylosin in antibiotic-producing strains of Streptomyces fradiae. Introduction of tlrB into Streptomyces lividans similarly confers tylosin resistance. Biochemical analysis of the rRNA from the two...... is dependent on the presence of the methyl group donor, S-adenosyl methionine. Analysis of the 74-mer RNA substrate by biochemical and mass spectrometric methods shows that TlrB adds a single methyl group to the base of G748. Homologues of TlrB in other bacteria have been revealed through database searches...

  4. Interactions of Notch1 and TLR4 signaling pathways in DRG neurons of in vivo and in vitro models of diabetic neuropathy.

    Science.gov (United States)

    Chen, Tianhua; Li, Hao; Yin, Yiting; Zhang, Yuanpin; Liu, Zhen; Liu, Huaxiang

    2017-11-02

    Understanding the interactions between Notch1 and toll-like receptor 4 (TLR4) signaling pathways in the development of diabetic peripheral neuropathy may lead to interpretation of the mechanisms and novel approaches for preventing diabetic neuropathic pain. In the present study, the interactions between Notch1 and TLR4 signaling pathways were investigated by using dorsal root ganglion (DRG) from diabetic neuropathic pain rats and cultured DRG neurons under high glucose challenge. The results showed that high glucose induced not only Notch1 mRNA, HES1 mRNA, and TLR4 mRNA expression, but also Notch1 intracellular domain (NICD1) and TLR4 protein expression in DRG neurons. The proportion of NICD1-immunoreactive (IR) and TLR4-IR neurons in DRG cultures was also increased after high glucose challenge. The above alterations could be partially reversed by inhibition of either Notch1 or TLR4 signaling pathway. Inhibition of either Notch1 or TLR4 signaling pathway could improve mechanical allodynia and thermal hyperalgesia thresholds. Inhibition of Notch1 or TLR4 signaling also decreased tumor necrosis factor-α (TNF-α) levels in DRG from diabetic neuropathic rats. These data imply that the interaction between Notch1 and TLR4 signaling pathways is one of the important mechanisms in the development or progression of diabetic neuropathy.

  5. Long-term activation of TLR3 by Poly(I:C induces inflammation and impairs lung function in mice

    Directory of Open Access Journals (Sweden)

    Alexopoulou Lena

    2009-06-01

    Full Text Available Abstract Background The immune mechanisms associated with infection-induced disease exacerbations in asthma and COPD are not fully understood. Toll-like receptor (TLR 3 has an important role in recognition of double-stranded viral RNA, which leads to the production of various inflammatory mediators. Thus, an understanding of TLR3 activation should provide insight into the mechanisms underlying virus-induced exacerbations of pulmonary diseases. Methods TLR3 knock-out (KO mice and C57B6 (WT mice were intranasally administered repeated doses of the synthetic double stranded RNA analog poly(I:C. Results There was a significant increase in total cells, especially neutrophils, in BALF samples from poly(I:C-treated mice. In addition, IL-6, CXCL10, JE, KC, mGCSF, CCL3, CCL5, and TNFα were up regulated. Histological analyses of the lungs revealed a cellular infiltrate in the interstitium and epithelial cell hypertrophy in small bronchioles. Associated with the pro-inflammatory effects of poly(I:C, the mice exhibited significant impairment of lung function both at baseline and in response to methacholine challenge as measured by whole body plethysmography and an invasive measure of airway resistance. Importantly, TLR3 KO mice were protected from poly(I:C-induced changes in lung function at baseline, which correlated with milder inflammation in the lung, and significantly reduced epithelial cell hypertrophy. Conclusion These findings demonstrate that TLR3 activation by poly(I:C modulates the local inflammatory response in the lung and suggest a critical role of TLR3 activation in driving lung function impairment. Thus, TLR3 activation may be one mechanism through which viral infections contribute toward exacerbation of respiratory disease.

  6. Human innate responses and adjuvant activity of TLR ligands in vivo in mice reconstituted with a human immune system.

    Science.gov (United States)

    Cheng, Liang; Zhang, Zheng; Li, Guangming; Li, Feng; Wang, Li; Zhang, Liguo; Zurawski, Sandra M; Zurawski, Gerard; Levy, Yves; Su, Lishan

    2017-10-27

    TLR ligands (TLR-Ls) represent a class of novel vaccine adjuvants. However, their immunologic effects in humans remain poorly defined in vivo. Using a humanized mouse model with a functional human immune system, we investigated how different TLR-Ls stimulated human innate immune response in vivo and their applications as vaccine adjuvants for enhancing human cellular immune response. We found that splenocytes from humanized mice showed identical responses to various TLR-Ls as human PBMCs in vitro. To our surprise, various TLR-Ls stimulated human cytokines and chemokines differently in vivo compared to that in vitro. For example, CpG-A was most efficient to induce IFN-α production in vitro. In contrast, CpG-B, R848 and Poly I:C stimulated much more IFN-α than CpG-A in vivo. Importantly, the human innate immune response to specific TLR-Ls in humanized mice was different from that reported in C57BL/6 mice, but similar to that reported in nonhuman primates. Furthermore, we found that different TLR-Ls distinctively activated and mobilized human plasmacytoid dendritic cells (pDCs), myeloid DCs (mDCs) and monocytes in different organs. Finally, we showed that, as adjuvants, CpG-B, R848 and Poly I:C can all enhance antigen specific CD4 + T cell response, while only R848 and Poly I:C induced CD8 + cytotoxic T cells response to a CD40-targeting HIV vaccine in humanized mice, correlated with their ability to activate human mDCs but not pDCs. We conclude that humanized mice serve as a highly relevant model to evaluate and rank the human immunologic effects of novel adjuvants in vivo prior to testing in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. In Vivo Role of TLR2 and MyD88 Signaling in Eliciting Innate Immune Responses in Staphylococcal Endophthalmitis

    Science.gov (United States)

    Talreja, Deepa; Singh, Pawan Kumar; Kumar, Ashok

    2015-01-01

    Purpose. The purpose of this study was to investigate the protective mechanisms evoked by TLR2 and MyD88 signaling in bacterial endophthalmitis in vivo. Methods. Endophthalmitis was induced in wild-type (WT), TLR2−/−, MyD88−/−, and Cnlp−/− mice by intravitreal injections of a laboratory strain (RN6390) and two endophthalmitis isolates of Staphylococcus aureus. Disease progression was monitored by assessing corneal and vitreous haze, bacterial burden, and retinal tissue damage. Levels of inflammatory cytokines/chemokines were determined using quantitative RT-PCR (qRT-PCR) and ELISA. Flow cytometry was used to assess neutrophil infiltration. Cathelicidin-related antimicrobial peptide (CRAMP) expression was determined by immunostaining and dot blot. Results. Eyes infected with either laboratory or clinical isolates exhibited higher levels of inflammatory mediators at the early stages of infection (≤24 hours) in WT mice than in TLR2−/− or MyD88−/− mice. However, their levels surpassed that of WT mice at the later stages of infection (>48 hours), coinciding with increased bacterial burden and retinal damage. Both TLR2−/− and MyD88−/− retinas produced reduced levels of CRAMP, and its deficiency (Cnlp−/−) rendered the mice susceptible to increased bacterial burden and retinal tissue damage as early as 1 day post infection. Analyses of inflammatory mediators and neutrophil levels in WT versus Cnlp−/− mice showed a trend similar to that observed in TLR2 and MyD88 KO mice. Furthermore, we observed that even a 10-fold lower infective dose of S. aureus was sufficient to cause endophthalmitis in TLR2−/− and MyD88−/− mice. Conclusions. TLR2 and MyD88 signaling plays an important role in protecting the retina from staphylococcal endophthalmitis by production of the antimicrobial peptide CRAMP. PMID:25678692

  8. Association of TLR7 variants with AIDS-like disease and AIDS vaccine efficacy in rhesus macaques.

    Directory of Open Access Journals (Sweden)

    Roman A Siddiqui

    Full Text Available In HIV infection, TLR7-triggered IFN-α production exerts a direct antiviral effect through the inhibition of viral replication, but may also be involved in immune pathogenesis leading to AIDS. TLR7 could also be an important mediator of vaccine efficacy. In this study, we analyzed polymorphisms in the X-linked TLR7 gene in the rhesus macaque model of AIDS. Upon resequencing of the TLR7 gene in 36 rhesus macaques of Indian origin, 12 polymorphic sites were detected. Next, we identified three tightly linked single nucleotide polymorphisms (SNP as being associated with survival time. Genotyping of 119 untreated, simian immunodeficiency virus (SIV-infected male rhesus macaques, including an 'MHC adjusted' subset, revealed that the three TLR7 SNPs are also significantly associated with set-point viral load. Surprisingly, this effect was not observed in 72 immunized SIV-infected male monkeys. We hypothesize (i that SNP c.13G>A in the leader peptide is causative for the observed genotype-phenotype association and that (ii the underlying mechanism is related to RNA secondary structure formation. Therefore, we investigated a fourth SNP (c.-17C>T, located 17 bp upstream of the ATG translation initiation codon, that is also potentially capable of influencing RNA structure. In c.13A carriers, neither set-point viral load nor survival time were related to the c.-17C>T genotype. In c.13G carriers, by contrast, the c.-17C allele was significantly associated with prolonged survival. Again, no such association was detected among immunized SIV-infected macaques. Our results highlight the dual role of TLR7 in immunodeficiency virus infection and vaccination and imply that it may be important to control human AIDS vaccine trials, not only for MHC genotype, but also for TLR7 genotype.

  9. Hyaluronan signaling during ozone-induced lung injury requires TLR4, MyD88, and TIRAP.

    Directory of Open Access Journals (Sweden)

    Zhuowei Li

    Full Text Available Ozone exposure is associated with exacerbation of reactive airways disease. We have previously reported that the damage-associated molecular pattern, hyaluronan, is required for the complete biological response to ambient ozone and that hyaluronan fragments signal through toll-like receptor 4 (TLR4. In this study, we further investigated the role of TLR4 adaptors in ozone-induced airway hyperresponsiveness (AHR and the direct response to hyaluronan fragments (HA. Using a murine model of AHR, C57BL/6J, TLR4-/-, MyD88-/-, and TIRAP-/- mice were characterized for AHR after exposure to either ozone (1 ppm × 3 h or HA fragments. Animals were characterized for AHR with methacholine challenge, cellular inflammation, lung injury, and production of pro-inflammatory cytokines. Ozone-exposed C57BL/6J mice developed cellular inflammation, lung injury, pro-inflammatory cytokines, and AHR, while mice deficient in TLR4, MyD88 or TIRAP demonstrated both reduced AHR and reduced levels of pro-inflammatory cytokines including TNFα, IL-1β, MCP-1, IL-6 and KC. The level of hyaluronan was increased after inhalation of ozone in each strain of mice. Direct challenge of mice to hyaluronan resulted in AHR in C57BL/6J mice, but not in TLR4-/-, MyD88-/-, or TIRAP-/- mice. HA-induced cytokine production in wild-type mice was significantly reduced in TLR4-/-, MyD88-/-, or TIRAP-/- mice. In conclusion, our findings support that ozone-induced airway hyperresponsiveness is dependent on the HA-TLR4-MyD88-TIRAP signaling pathway.

  10. Respiratory Syncytial Virus Fusion Protein-Induced Toll-Like Receptor 4 (TLR4) Signaling Is Inhibited by the TLR4 Antagonists Rhodobacter sphaeroides Lipopolysaccharide and Eritoran (E5564) and Requires Direct Interaction with MD-2

    Science.gov (United States)

    Rallabhandi, Prasad; Phillips, Rachel L.; Boukhvalova, Marina S.; Pletneva, Lioubov M.; Shirey, Kari Ann; Gioannini, Theresa L.; Weiss, Jerrold P.; Chow, Jesse C.; Hawkins, Lynn D.; Vogel, Stefanie N.; Blanco, Jorge C. G.

    2012-01-01

    ABSTRACT Respiratory syncytial virus (RSV) is a leading cause of infant mortality worldwide. Toll-like receptor 4 (TLR4), a signaling receptor for structurally diverse microbe-associated molecular patterns, is activated by the RSV fusion (F) protein and by bacterial lipopolysaccharide (LPS) in a CD14-dependent manner. TLR4 signaling by LPS also requires the presence of an additional protein, MD-2. Thus, it is possible that F protein-mediated TLR4 activation relies on MD-2 as well, although this hypothesis has not been formally tested. LPS-free RSV F protein was found to activate NF-κB in HEK293T transfectants that express wild-type (WT) TLR4 and CD14, but only when MD-2 was coexpressed. These findings were confirmed by measuring F-protein-induced interleukin 1β (IL-1β) mRNA in WT versus MD-2−/− macrophages, where MD-2−/− macrophages failed to show IL-1β expression upon F-protein treatment, in contrast to the WT. Both Rhodobacter sphaeroides LPS and synthetic E5564 (eritoran), LPS antagonists that inhibit TLR4 signaling by binding a hydrophobic pocket in MD-2, significantly reduced RSV F-protein-mediated TLR4 activity in HEK293T-TLR4–CD14–MD-2 transfectants in a dose-dependent manner, while TLR4-independent NF-κB activation by tumor necrosis factor alpha (TNF-α) was unaffected. In vitro coimmunoprecipitation studies confirmed a physical interaction between native RSV F protein and MD-2. Further, we demonstrated that the N-terminal domain of the F1 segment of RSV F protein interacts with MD-2. These data provide new insights into the importance of MD-2 in RSV F-protein-mediated TLR4 activation. Thus, targeting the interaction between MD-2 and RSV F protein may potentially lead to novel therapeutic approaches to help control RSV-induced inflammation and pathology. PMID:22872782

  11. Vaccination inhibits TLR2 transcription via suppression of GR nuclear translocation and binding to TLR2 promoter in porcine lung infected with Mycoplasma hyopneumoniae.

    Science.gov (United States)

    Sun, Zhiyuan; Liu, Maojun; Zou, Huafeng; Li, Xian; Shao, Guoqing; Zhao, Ruqian

    2013-12-27

    Toll-like receptors (TLRs) and glucocorticoid receptor (GR) act respectively as effectors of innate immune and stress responses. The crosstalk between them is critical for the maintenance of homeostasis during the immune response. Vaccination is known to boost adaptive immunity, yet it remains elusive whether vaccination may affect GR/TLR interactions following infection. Duroc×Meishan crossbred piglets were allocated to three groups. The control group (CC) received neither vaccination nor infection; the non-vaccinated infection group (NI) was artificially infected intratracheally with Mycoplasma hyopneumoniae (M. hyopneumoniae); while the vaccinated, infected group (VI) was vaccinated intramuscularly with inactivated M. hyopneumoniae one month before infection. The clinical signs and macroscopic lung lesions were significantly reduced by vaccination. However, vaccination did not affect the concentration of M. hyopneumoniae DNA in the lung. Serum cortisol was significantly decreased in both NI and VI pigs (Phyopneumoniae-induced lung lesions in the pig. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. TLR4 and TLR7/8 Adjuvant Combinations Generate Different Vaccine Antigen-Specific Immune Outcomes in Minipigs when Administered via the ID or IN Routes.

    Directory of Open Access Journals (Sweden)

    Paul F McKay

    Full Text Available The induction of high levels of systemic and mucosal humoral immunity is a key goal for many prophylactic vaccines. However, adjuvant strategies developed in mice have often performed poorly in the clinic. Due to their closer similarity to humans, minipigs may provide a more accurate picture of adjuvant performance. Based on their complementary signalling pathways, we assessed humoral immune responses to model antigens after co-administration with the toll-like receptor 4 (TLR4 stimulator glucopyranosyl lipid adjuvant (GLA-AF or the TLR7/8 agonist resiquimod (R848 (alone and in combination via the intradermal (ID, intranasal (IN or combined routes in the Gottingen minipig animal model. Surprisingly, we discovered that while GLA-AF additively enhanced the adjuvant effect of R848 when injected ID, it abrogated the adjuvant activity of R848 after IN inoculation. We then performed a route comparison study using a CN54 gp140 HIV Envelope model antigen adjuvanted with R848 + GLA-AF (ID or R848 alone (IN. Animals receiving priming inoculations via one route were then boosted by the alternate route. Although differences were observed in the priming phase (IN or ID, responses converged upon boosting by the alternative route with no observable impact resultant from the order of administration (ID/IN vs IN/ID. Specific IgG responses were measured at a distal mucosal site (vaginal, although there was no evidence of mucosal linkage as these closely reflected serum antibody levels. These data indicate that the complex in vivo cross-talk between innate pathways are likely tissue specific and cannot be predicted by simple in vitro models.

  13. TLR4-HMGB1 signaling pathway affects the inflammatory reaction of autoimmune myositis by regulating MHC-I.

    Science.gov (United States)

    Wan, Zemin; Zhang, Xiujuan; Peng, Anping; He, Min; Lei, Zhenhua; Wang, Yunxiu

    2016-12-01

    To analyze the effects of TLR4 on the expression of the HMGB1, MHC-I and downstream cytokines IL-6 and TNF-α, and to investigate the biological role of the TLR4-HMGB1 signaling pathway in the development of the autoimmune myositis. We built mice models with experimental autoimmune myositis (EAM) and used the inverted screen experiment to measure their muscle endurance; we also examined inflammatory infiltration of muscle tissues after HE staining; and we assessed the expression of MHC-I using immunohistochemistry. In addition, peripheral blood mononuclear cells (PBMC) were extracted and flow cytometry was utilized to detect the effect of IFN-γ on the expression of MHC-I. Furthermore, PBMCs were treated with IFN-γ, anti-TLR4, anti-HMGB1 and anti-MHC-I. Real-time PCR and western blotting were employed to examine the expressions of TLR4, HMGB1 and MHC-I in different groups. The ELISA method was also utilized to detect the expression of the downstream cytokines TNF-α and IL-6. The expressions of TLR4, HMGB1 and MHC-I in muscle tissues from mice with EAM were significantly higher than those in the control group (all Pmyositis inflammation by regulating the expression of MHC-I and other pro-inflammatory cytokines. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. TLR-4 engagement of dendritic cells confers a BST-2/tetherin-mediated restriction of HIV-1 infection to CD4+ T cells across the virological synapse

    Directory of Open Access Journals (Sweden)

    Blanchet Fabien P

    2013-01-01

    Full Text Available Abstract Background Dendritic cells and their subsets, located at mucosal surfaces, are among the first immune cells to encounter disseminating pathogens. The cellular restriction factor BST-2/tetherin (also known as CD317 or HM1.24 potently restricts HIV-1 release by retaining viral particles at the cell surface in many cell types, including primary cells such as macrophages. However, BST-2/tetherin does not efficiently restrict HIV-1 infection in immature dendritic cells. Results We now report that BST-2/tetherin expression in myeloid (myDC and monocyte-derived dendritic cells (DC can be significantly up-regulated by IFN-α treatment and TLR-4 engagement with LPS. In contrast to HeLa or 293T cells, infectious HIV-1 release in immature DC and IFN-α–matured DC was only modestly affected in the absence of Vpu compared to wild-type viruses. Strikingly, immunofluorescence analysis revealed that BST-2/tetherin was excluded from HIV containing tetraspanin-enriched microdomains (TEMs in both immature DC and IFN-α–matured DC. In contrast, in LPS-mediated mature DC, BST-2/tetherin exerted a significant restriction in transfer of HIV-1 infection to CD4+ T cells. Additionally, LPS, but not IFN-α stimulation of immature DC, leads to a dramatic redistribution of cellular restriction factors to the TEM as well as at the virological synapse between DC and CD4+ T cells. Conclusions In conclusion, we demonstrate that TLR-4 engagement in immature DC significantly up-regulates the intrinsic antiviral activity of BST-2/tetherin, during cis-infection of CD4+ T cells across the DC/T cell virological synapse. Manipulating the function and potency of cellular restriction factors such as BST-2/tetherin to HIV-1 infection, has implications in the design of antiviral therapeutic strategies.

  15. Polyethylenimine-based siRNA nanocomplexes reprogram tumor-associated dendritic cells via TLR5 to elicit therapeutic antitumor immunity.

    Science.gov (United States)

    Cubillos-Ruiz, Juan R; Engle, Xavier; Scarlett, Uciane K; Martinez, Diana; Barber, Amorette; Elgueta, Raul; Wang, Li; Nesbeth, Yolanda; Durant, Yvon; Gewirtz, Andrew T; Sentman, Charles L; Kedl, Ross; Conejo-Garcia, Jose R

    2009-08-01

    The success of clinically relevant immunotherapies requires reversing tumor-induced immunosuppression. Here we demonstrated that linear polyethylenimine-based (PEI-based) nanoparticles encapsulating siRNA were preferentially and avidly engulfed by regulatory DCs expressing CD11c and programmed cell death 1-ligand 1 (PD-L1) at ovarian cancer locations in mice. PEI-siRNA uptake transformed these DCs from immunosuppressive cells to efficient antigen-presenting cells that activated tumor-reactive lymphocytes and exerted direct tumoricidal activity, both in vivo and in situ. PEI triggered robust and selective TLR5 activation in vitro and elicited the production of hallmark TLR5-inducible cytokines in WT mice, but not in Tlr5-/- littermates. Thus, PEI is a TLR5 agonist that, to our knowledge, was not previously recognized. In addition, PEI-complexed nontargeting siRNA oligonucleotides stimulated TLR3 and TLR7. The nonspecific activation of multiple TLRs (specifically, TLR5 and TLR7) reversed the tolerogenic phenotype of human and mouse ovarian tumor-associated DCs. In ovarian carcinoma-bearing mice, this induced T cell-mediated tumor regression and prolonged survival in a manner dependent upon myeloid differentiation primary response gene 88 (MyD88; i.e., independent of TLR3). Furthermore, gene-specific siRNA-PEI nanocomplexes that silenced immunosuppressive molecules on mouse tumor-associated DCs elicited discernibly superior antitumor immunity and enhanced therapeutic effects compared with nontargeting siRNA-PEI nanocomplexes. Our results demonstrate that the intrinsic TLR5 and TLR7 stimulation of siRNA-PEI nanoparticles synergizes with the gene-specific silencing activity of siRNA to transform tumor-infiltrating regulatory DCs into DCs capable of promoting therapeutic antitumor immunity.

  16. The TLR4 D299G and T399I SNPs are constitutively active to up-regulate expression of Trif-dependent genes.

    Directory of Open Access Journals (Sweden)

    Georgina L Hold

    Full Text Available Dysregulated Toll-Like Receptor (TLR signalling and genetic polymorphisms in these proteins are linked to many human diseases. We investigated TLR4 functional variants D299G and T399I to assess the impact on LPS-induced responsiveness in comparison to wild-type TLR4. The mechanism by which this occurs in unclear as these SNPs do not lie within the lipid A binding domain or dimerisation sites of the LPS-TLR4/MD2 receptor complexes. Transfection of TLR4D299G, TLR4T399I or TLR4D299G. T399I into HEK cells resulted in constitutive activation of an NF-κB reporter gene and a blunting of the LPS-induced reporter activation compared to WT-TLR4. Unstimulated human monocyte/macrophages, from patients with the D299G and T399I SNPs demonstrated a downregulation of many genes, particularly Tram/Trif signalling pathway constitutents compared to the TLR4 wild-type subjects supporting the concept of basal receptor activity. Monocyte/macrophages from carriers of the TLR4 D299G and T399I polymorphisms stimulated with LPS showed >6 fold lower levels of NF-κB and ∼12 fold higher IFN-β gene expression levels compared to wild-type subjects (P<0.05; MWU test and dramatically altered resultant cytokine profiles. We conclude that these TLR4 SNPs affect constitutive receptor activity which impacts on the hosts ability to respond to LPS challenge leading to a dysregulated sub-optimal immune response to infection.

  17. Increased Expression of the Innate Immune Receptor TLR10 in Obesity and Type-2 Diabetes: Association with ROS-Mediated Oxidative Stress.

    Science.gov (United States)

    Sindhu, Sardar; Akhter, Nadeem; Kochumon, Shihab; Thomas, Reeby; Wilson, Ajit; Shenouda, Steve; Tuomilehto, Jaakko; Ahmad, Rasheed

    2018-01-01

    Metabolic diseases such as obesity and type-2 diabetes (T2D) are known to be associated with chronic low-grade inflammation called metabolic inflammation together with an oxidative stress milieu found in the expanding adipose tissue. The innate immune Toll-like receptors (TLR) such as TLR2 and TLR4 have emerged as key players in metabolic inflammation; nonetheless, TLR10 expression in the adipose tissue and its significance in obesity/T2D remain unclear. TLR10 gene expression was determined in the adipose tissue samples from healthy non-diabetic and T2D individuals, 13 each, using real-time RT-PCR. TLR10 protein expression was determined by immunohistochemistry, confocal microscopy, and flow cytometry. Regarding in vitro studies, THP-1 cells, peripheral blood mononuclear cells (PBMC), or primary monocytes were treated with hydrogen peroxide (H2O2) for induction of reactive oxygen species (ROS)-mediated oxidative stress. Superoxide dismutase (SOD) activity was measured using a commercial kit. Data (mean±SEM) were compared using unpaired student's t-test and Pobesity as well as T2D which correlated with body mass index (BMI). ROS-mediated oxidative stress induced high levels of TLR10 gene/protein expression in monocytic cells and PBMC. In these cells, oxidative stress induced a time-dependent increase in SOD activity. Pre-treatment of cells with anti-oxidants/ROS scavengers diminished the expression of TLR10. ROS-induced TLR10 expression involved the nuclear factor-kappaB (NF-κB)/mitogen activated protein kinase (MAPK) signaling as well as endoplasmic reticulum (ER) stress. H2O2-induced oxidative stress interacted synergistically with palmitate to trigger the expression of TLR10 which associated with enhanced expression of proinflammatory cytokines/chemokine. Oxidative stress induces the expression of TLR10 which may represent an immune marker for metabolic inflammation. © 2018 The Author(s). Published by S. Karger AG, Basel.

  18. Vitamin K2 can suppress the expression of Toll-like receptor 2 (TLR2) and TLR4, and inhibit calcification of aortic intima in ApoE-/- mice as well as smooth muscle cells.

    Science.gov (United States)

    Wang, Zhaojun; Wang, Zhongqun; Zhu, Jie; Long, Xinguang; Yan, Jinchuan

    2018-02-01

    Background and objectives Vascular calcification is a common complication in atherosclerosis. Accumulating evidence showed that Toll-like receptors (TLRs) mediate pro-inflammatory and atherosclerosis. Recent studies demonstrated that vascular calcification is one of the detrimental effects of vitamin K (Vit K) antagonists. However, the effects of Vit K on the expression of TLR2 and 4 and intimal calcification in artery remained unidentified. Methods and results Eighteen ApoE -/- mice were randomly divided into model group, Vit K-treated group, and control group. The mice of model and Vit K-treated group were fed with high-fat diet, while control group mice were fed with normal diet. Mice of Vit K-treated group were administered orally with vitamin K2 (40 mg.kg -1 .day -1 ) for 12 weeks. Twelve weeks later the aortic sections of mice were acquired and stained with hematoxylin and eosin and von Kossa, respectively. Calcium content and activity of alkaline phosphatase (ALP) at aortic tissues were measured. The expression levels of TLR2 and TLR4 in aorta sections were detected by immunohistochemisty and RT-PCR, respectively. The effects of Vit K on cellular calcification were further studied in A7r5 SMCs. Results demonstrated that high-fat diet induced typical atherosclerosis with intimal calcification in ApoE -/- mice, while in Vit K-treated group atherosclerosis and calcium deposits were not serious; Vit K2 also inhibited cellular calcification in A7r5 SMCs. Quantitative analysis showed that calcium and ALP activity at aortic tissues in the Vit K-treated mice were significantly lower than that of the model group ( P < 0.01); Compared to the control group, the expression levels of TLR2 and TLR4 in the model group were significantly higher ( P < 0.05), while in Vit K-treated group the levels of TLR2 and 4 were significantly lower than that in the model group. Furthermore, the content of calcium was positively related to the expression levels of TLR2 and TLR4

  19. A tryptophan-rich motif in the human parainfluenza virus type 2 V protein is critical for the blockade of toll-like receptor 7 (TLR7)- and TLR9-dependent signaling.

    Science.gov (United States)

    Kitagawa, Yoshinori; Yamaguchi, Mayu; Zhou, Min; Komatsu, Takayuki; Nishio, Machiko; Sugiyama, Tsuyoshi; Takeuchi, Kenji; Itoh, Masae; Gotoh, Bin

    2011-05-01

    Plasmacytoid dendritic cells (pDCs) do not produce alpha interferon (IFN-α) unless viruses cause a systemic infection or overcome the first-line defense provided by conventional DCs and macrophages. We show here that even paramyxoviruses, whose infections are restricted to the respiratory tract, have a V protein able to prevent Toll-like receptor 7 (TLR7)- and TLR9-dependent IFN-α induction specific to pDCs. Mutational analysis of human parainfluenza virus type 2 demonstrates that the second Trp residue of the Trp-rich motif (Trp-X(3)-Trp-X(9)-Trp) in the C-terminal domain unique to V, a determinant for IRF7 binding, is critical for the blockade of TLR7/9-dependent signaling.

  20. Lipopolysaccharide promotes lipid accumulation in human adventitial fibroblasts via TLR4-NF-κB pathway

    Directory of Open Access Journals (Sweden)

    Wang Jun

    2012-10-01

    Full Text Available Abstract Background Atherosclerosis is a chronic degenerative disease of the arteries and is thought to be one of the most common causes of death globally. In recent years, the functions of adventitial fibroblasts in the development of atherosclerosis and tissue repair have gained increased interests. LPS can increase the morbidity and mortality of atherosclerosis-associated cardiovascular disease. Although LPS increases neointimal via TLR4 activation has been reported, how LPS augments atherogenesis through acting on adventitial fibroblasts is still unknown. Here we explored lipid deposition within adventitial fibroblasts mediated by lipopolysaccharide (LPS to imitate inflammatory conditions. Results In our study, LPS enhanced lipid deposition by the up-regulated expression of adipose differentiation-related protein (ADRP as the silencing of ADRP abrogated lipid deposition in LPS-activated adventitial fibroblasts. In addition, pre-treatment with anti-Toll-like receptor 4 (TLR4 antibody diminished the LPS-induced lipid deposition and ADRP expression. Moreover, LPS induced translocation of nuclear factor-κB (NF-κB, which could markedly up-regulate lipid deposition as pre-treatment with the NF-κB inhibitor, PDTC, significantly reduced lipid droplets. In addition, the lowering lipid accumulation was accompanied with the decreased ADRP expression. Furthermore, LPS-induced adventitial fibroblasts secreted more monocyte chemoattractant protein (MCP-1, compared with transforming growth factor-β1 (TGF-β1. Conclusions Taken together, these results suggest that LPS promotes lipid accumulation via the up-regulation of ADRP expression through TLR4 activated downstream of NF-κB in adventitial fibroblasts. Increased levels of MCP-1 released from LPS-activated adventitial fibroblasts and lipid accumulation may accelerate monocytes recruitment and lipid-laden macrophage foam cells formation. Here, our study provides a new explanation as to how bacterial

  1. Lipopolysaccharide promotes lipid accumulation in human adventitial fibroblasts via TLR4-NF-κB pathway.

    Science.gov (United States)

    Wang, Jun; Si, Yanfang; Wu, Chen; Sun, Lu; Ma, Yudong; Ge, Aili; Li, Baomin

    2012-10-17

    Atherosclerosis is a chronic degenerative disease of the arteries and is thought to be one of the most common causes of death globally. In recent years, the functions of adventitial fibroblasts in the development of atherosclerosis and tissue repair have gained increased interests. LPS can increase the morbidity and mortality of atherosclerosis-associated cardiovascular disease. Although LPS increases neointimal via TLR4 activation has been reported, how LPS augments atherogenesis through acting on adventitial fibroblasts is still unknown. Here we explored lipid deposition within adventitial fibroblasts mediated by lipopolysaccharide (LPS) to imitate inflammatory conditions. In our study, LPS enhanced lipid deposition by the up-regulated expression of adipose differentiation-related protein (ADRP) as the silencing of ADRP abrogated lipid deposition in LPS-activated adventitial fibroblasts. In addition, pre-treatment with anti-Toll-like receptor 4 (TLR4) antibody diminished the LPS-induced lipid deposition and ADRP expression. Moreover, LPS induced translocation of nuclear factor-κB (NF-κB), which could markedly up-regulate lipid deposition as pre-treatment with the NF-κB inhibitor, PDTC, significantly reduced lipid droplets. In addition, the lowering lipid accumulation was accompanied with the decreased ADRP expression. Furthermore, LPS-induced adventitial fibroblasts secreted more monocyte chemoattractant protein (MCP-1), compared with transforming growth factor-β1 (TGF-β1). Taken together, these results suggest that LPS promotes lipid accumulation via the up-regulation of ADRP expression through TLR4 activated downstream of NF-κB in adventitial fibroblasts. Increased levels of MCP-1 released from LPS-activated adventitial fibroblasts and lipid accumulation may accelerate monocytes recruitment and lipid-laden macrophage foam cells formation. Here, our study provides a new explanation as to how bacterial infection contributes to the pathological process of

  2. The TLR7 agonist Imiquimod promote the immunogenicity of msenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Li Zhang

    2015-01-01

    Full Text Available BACKGROUND: Mesenchymal stem cells (MSCs are considered the best candidate in stem cells therapy due to their multipotent differentiation ability, low expression of co-stimulatory molecules (CD80, CD86, CD34 and HLA-II and immunosuppression effects on in vivo immune responses. MSCs were now widely used in clinical trials but received no encourage results. The major problem was the fate of engrafted MSCs in vivo could not be defined. Some studies indicated that MSCs could induce immune response and result in the damage and rejection of MSCs. As toll like receptors (TLRs are important in inducing of immune responses, in this study we study the role of TLR7 in mediating the immune status of MSCs isolated from umbilical cord. RESULTS: Our results indicated that TLR7 agonist Imiquimod could increase the proliferation of PBMC isolated from healthy human volunteers and release of lactate dehydrogenase (LDH in supernatant from PBMC-UCMSCs co-culture system. Flow cytometry and quantitative PCR also confirmed the regulated expression of surface co-stimulatory molecules and pro-inflammatory genes (IL-6, IL-8, IL-12, TGF-β and TNF-α. And the down-regulation expression of stem cell markers also confirmed the loss of stemness of UCMSCs. We also found that the osteo-differentiation ability of UCMSCs was enhanced in the presence of Imiquimod. CONCLUSION: To our knowledge, this is the first report that activation of TLR7 pathway increases the immunogenicity of UCMSCs. Extensive researches have now been conducted to study whether the change of immune status will be help in tumor rejection based on the tumor-tropism of MSCs.

  3. Association of gene variants in TLR4 and IL-6 genes with Perthes disease

    Directory of Open Access Journals (Sweden)

    Srzentić Sanja

    2014-01-01

    Full Text Available Introduction. Perthes disease is idiopathic avascular osteonecrosis of the hip in children, with unknown etiology. Inflammation is present during development of Perthes disease and it is known that this process influences bone remodeling. Objective. Since genetic studies related to inflammation have not been performed in Perthes disease so far, the aim of this study was to analyze the association of frequencies of genetic variants of immune response genes, toll-like receptor 4 (TLR4 and interleukin-6 (IL-6, with this disease. Methods. The study cohort consisted of 37 patients with Perthes disease and 50 healthy controls. Polymorphisms of well described inflammatory mediators: TLR4 (Asp299Gly, Thr399Ile and IL-6 (G-174C, G- 597A were determined by polymerase chain reaction restriction fragment length polymorphism method. Results. IL-6 G-174C and G-597A polymorphisms were in complete linkage disequilibrium. A statistically significant increase of heterozygote subjects for IL-6 G-174C/G-597A was found in controls in comparison to Perthes patient group (p=0.047, OR=2.49, 95% CI=1.00-6.21. Also, the patient group for IL-6 G-174C/G- 597A polymorphisms was not in Hardy-Weinberg equilibrium. No statistically significant differences were found between patient and control groups for TLR4 analyzed polymorphisms. A stratified analysis by the age at disease onset also did not reveal any significant difference for all analyzed polymorphisms. Conclusion. Our study revealed that heterozygote subjects for the IL-6 G-174C/G-597A polymorphisms were significantly overrepresented in the control group than in the Perthes patient group. Consequently, we concluded that children who are heterozygous for these polymorphisms have a lower chance of developing Perthes disease than carriers of both homozygote genotypes. [Projekat Ministarstva nauke Republike Srbije, br. III41004

  4. [Polymorphism of CD209 and TLR3 genes in populations of North Eurasia].

    Science.gov (United States)

    Barkhash, A V; Babenko, V N; Voevoda, M I; Romaschenko, A G

    2016-06-01

    The DC-SIGN (dendritic cell-specific intercellular adhesion molecule (ICAM)-3-grabbing non-integrin) and TLR3 (toll-like receptor 3) proteins are key effectors of the innate immunity and particularly play an important role in the organism’s antiviral defense as pattern-recognition receptors. Previously, we demonstrated that certain genotypes and alleles of single nucleotide polymorphisms (SNPs) rs2287886 (G/A) in the promoter region of the CD209 gene (encoding DC-SIGN) and rs3775291 (G/A, Leu412Phe) in the exon 4 of the TLR3 gene are associated with human predisposition to tick-borne encephalitis in the Russian population. In the present work, the distribution of genotype and allele frequencies for these SNPs was studied in seven populations of North Eurasia, including Caucasians (Russians and Germans (from Altai region)), Central Asian Mongoloids (Altaians, Khakass, Tuvinians, and Shorians), and Arctic Mongoloids (Chukchi). It was found that the CD209 gene rs2287886 SNP A/A genotype and A allele, as well as the TLR3 gene rs3775291 SNP G/G genotype and G allele (the frequencies of which in our previous studies were increased in tick-borne encephalitis patients as compared with the population control (Russian citizens of Novosibirsk)), are preserved with a high frequency in Central Asian Mongoloids (who for a long time regularly came in contact with tick-borne encephalitis virus in places of their habitation). We suggested that predisposition to tick-borne encephalitis in Central Asian Mongoloid populations can be predetermined by a different set of genes and their polymorphisms than in the Russian population.

  5. TLR-4 and CD14 Genotypes and Soluble CD14: Could They Predispose to Coronary Atherosclerosis?

    Directory of Open Access Journals (Sweden)

    Maria Kalliopi Konstantinidou

    2016-03-01

    Full Text Available Background: Inflammatory mechanisms are key to the pathogenesis of atherosclerosis. Functional polymorphisms of TLR-4, Asp299Gly and Thr399Ile, CD14 promoter area C260T polymorphism and plasma levels of soluble CD14 are studied in subjects with Coronary Artery Disease (CAD. Methods: DNA was obtained from 100 human paraffin-embedded aortic specimens, from cadavers with known coronary atheromatosis (Group A and 100 blood samples from patients with CAD, as detected by cardiac Multi-Detector-row-Computed-Tomography (MDCT (Group B. Our control group consisted of 100 healthy individuals (Group C. Genotyping was performed by Restriction Fragment Length Polymorphism-Polymerase Chain Reaction (RFLP-PCR. Plasma levels of sCD14 were measured with ELISA. Results: For TLR-4 Asp299Gly and Thr399Ile polymorphisms, no statistically significant differences were observed. Regarding the C260T polymorphism, frequencies of T allele were significantly higher in the control group compared to the case group (p = 0.05. The Odds Ratio (OR showed statistically significant association of TT genotype with healthy individuals (OR 0.25, 95% Confidence Interval CI 0.10–0.62, p = 0.0017. Plasma levels of sCD14 in patients with CAD (mean value = 1.35 μg/mL were reduced when compared to reference value. Conclusions: The studied polymorphisms ofTLR-4 showed no association with CAD. Conversely, the functional polymorphism of CD14 has a statistically significant difference in expression between healthy and affected by CAD individuals.

  6. Expression of Tumor Necrosis Factor Receptor 2 Characterizes TLR9-Driven Formation of Interleukin-10-Producing B Cells

    Directory of Open Access Journals (Sweden)

    Olga Ticha

    2018-01-01

    Full Text Available B cell-derived interleukin-10 (IL-10 production has been described as a hallmark for regulatory function in B lymphocytes. However, there is an ongoing debate on the origin of IL-10-secreting B cells and lack of specific surface markers has turned into an important obstacle for studying human B regulatory cells. In this study, we propose that tumor necrosis factor receptor 2 (TNFR2 expression can be used for enrichment of IL-10-secreting B cells. Our data confirm that IL-10 production can be induced by TLR9 stimulation with CpG ODN and that IL-10 secretion accompanies differentiation of peripheral blood B cells into plasma blasts. We further show that CpG ODN stimulation induces TNFR2 expression, which correlates with IL-10 secretion and terminal differentiation. Indeed, flow cytometric sorting of TNFR2+ B cells revealed that TNFR2+ and TNFR2− fractions correspond to IL-10+ and IL-10− fractions, respectively. Furthermore, CpG-induced TNFR2+ B cells were predominantly found in the IgM+ CD27+ B cell subset and spontaneously released immunoglobulin. Finally, our data corroborate the functional impact of TNFR2 by demonstrating that stimulation with a TNFR2 agonist significantly augments IL-10 and IL-6 production in B cells. Altogether, our data highlight a new role for TNFR2 in IL-10-secreting human B lymphocytes along with the potential to exploit this finding for sorting and isolation of this currently ill-defined B cell subset.

  7. Procyanidin dimer B2-mediated IRAK-M induction negatively regulates TLR4 signaling in macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Nak-Yun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Yang, Mi-So [Department of Microbiology, Infection Signaling Network Research Center, College of Medicine, Chungnam National University, Daejeon (Korea, Republic of); Song, Du-Sub [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); School of life sciences and Biotechnology, Korea University 5-ka, Anam-Dong, Sungbuk-ku, Seoul 136-701 (Korea, Republic of); Kim, Jae-Kyung; Park, Jong-Heum; Song, Beom-Seok; Park, Sang-Hyun; Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Park, Hyun-Jin [School of life sciences and Biotechnology, Korea University 5-ka, Anam-Dong, Sungbuk-ku, Seoul 136-701 (Korea, Republic of); Kim, Jae-Hun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Byun, Eui-Baek, E-mail: ebbyun80@kaeri.re.kr [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Byun, Eui-Hong, E-mail: ehbyun80@kongju.ac.k [Department of Food Science and Technology, Kongju National University, Yesan 340-800 (Korea, Republic of)

    2013-08-16

    Highlights: •Pro B2 elevated the expression of IRAK-M, a negative regulator of TLR signaling. •LPS-induced expression of cell surface molecules was inhibited by Pro B2. •LPS-induced production of pro-inflammatory cytokines was inhibited by Pro B2. •Pro B2 inhibited LPS-induced activation of MAPKs and NF-κB through IRAK-M. •Pro B2 inactivated naïve T cells by inhibiting LPS-induced cytokines via IRAK-M. -- Abstract: Polyphenolic compounds have been found to possess a wide range of physiological activities that may contribute to their beneficial effects against inflammation-related diseases; however, the molecular mechanisms underlying this anti-inflammatory activity are not completely characterized, and many features remain to be elucidated. In this study, we investigated the molecular basis for the down-regulation of toll-like receptor 4 (TLR4) signal transduction by procyanidin dimer B2 (Pro B2) in macrophages. Pro B2 markedly elevated the expression of the interleukin (IL)-1 receptor-associated kinase (IRAK)-M protein, a negative regulator of TLR signaling. Lipopolysaccharide (LPS)-induced expression of cell surface molecules (CD80, CD86, and MHC class I/II) and production of pro-inflammatory cytokines (tumor necrosis factor-α, IL-1β, IL-6, and IL-12p70) were inhibited by Pro B2, and this action was prevented by IRAK-M silencing. In addition, Pro B2-treated macrophages inhibited LPS-induced activation of mitogen-activated protein kinases such as extracellular signal-regulated kinase 1/2, p38, and c-Jun N-terminal kinase and the translocation of nuclear factor κB and p65 through IRAK-M. We also found that Pro B2-treated macrophages inactivated naïve T cells by inhibiting LPS-induced interferon-γ and IL-2 secretion through IRAK-M. These novel findings provide new insights into the understanding of negative regulatory mechanisms of the TLR4 signaling pathway and the immune-pharmacological role of Pro B2 in the immune response against the development

  8. Efectos moduladores del etanol sobre el sistema inmunitario: papel de los receptores TLR4

    OpenAIRE

    Fernández Lizarbe, Sara

    2010-01-01

    Trabajos clínicos y experimentales han demostrado que el etanol altera al sistema inmunitario. Aunque los mecanismos moleculares se desconocen, se ha demostrado que sus acciones sobre el sistema inmunitario son complejas y dependen de la dosis, el tiempo de exposición (agudo o crónico), tipo celular y presencia o ausencia de estímulos adicionales, como patógenos. Evidencias recientes indican el papel de los receptores tipo Toll (TLR) en la respuesta inmunitaria innata y, posiblemente, en...

  9. Saturated fatty acids enhance TLR4 immune pathways in human trophoblasts.

    Science.gov (United States)

    Yang, Xiaohua; Haghiac, Maricela; Glazebrook, Patricia; Minium, Judi; Catalano, Patrick M; Hauguel-de Mouzon, Sylvie

    2015-09-01

    What are the effects of fatty acids on placental inflammatory cytokine with respect to toll-like receptor-4/nuclear factor-kappa B (TLR4/NF-kB)? Exogenous fatty acids induce a pro-inflammatory cytokine response in human placental cells in vitro via activation of TLR4 signaling pathways. The placenta is exposed to changes in circulating maternal fatty acid concentrations throughout pregnancy. Fatty acids are master regulators of innate immune pathways through recruitment of toll-like receptors and activation of cytokine synthesis. Trophoblast cells isolated from 14 normal term human placentas were incubated with long chain fatty acids (FA) of different carbon length and degree of saturation. The expression and secretion of interleukin-6 (IL-6), IL-8 and tumor necrosis factor-alpha (TNF-α) were measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. Antibodies against TLR4 ligand binding domain, downstream signaling and anti-p65 NFkB-inhibitor were used to characterize the pathways of FA action. General approach used primary human term trophoblast cell culture. Methods and end-points used real-time quantitative PCR, cytokine measurements, immunohistochemistry, western blots. The long chain saturated fatty acids, stearic and palmitic (PA), stimulated the synthesis as well as the release of TNF-α, IL-6 and IL-8 by trophoblast cells (2- to 6-fold, P acids did not modify cytokine expression significantly. Palmitate-induced inflammatory effects were mediated via TLR4 activation, NF-kB phosphorylation and nuclear translocation. TNF-α protein level was close to the limit of detection in the culture medium even when cells were cultured with PA. These mechanisms open the way to a better understanding of how changes in maternal lipid homeostasis may regulate placental inflammatory status. X.Y. was recipient of fellowship award from West China Second University Hospital, Sichuan University (NIH HD 22965-19). The authors have nothing

  10. A Tryptophan-Rich Motif in the Human Parainfluenza Virus Type 2 V Protein Is Critical for the Blockade of Toll-Like Receptor 7 (TLR7)- and TLR9-Dependent Signaling▿

    OpenAIRE

    Kitagawa, Yoshinori; Yamaguchi, Mayu; Zhou, Min; Komatsu, Takayuki; Nishio, Machiko; Sugiyama, Tsuyoshi; Takeuchi, Kenji; Itoh, Masae; Gotoh, Bin

    2011-01-01

    Plasmacytoid dendritic cells (pDCs) do not produce alpha interferon (IFN-α) unless viruses cause a systemic infection or overcome the first-line defense provided by conventional DCs and macrophages. We show here that even paramyxoviruses, whose infections are restricted to the respiratory tract, have a V protein able to prevent Toll-like receptor 7 (TLR7)- and TLR9-dependent IFN-α induction specific to pDCs. Mutational analysis of human parainfluenza virus type 2 demonstrates that the second ...

  11. Sublingual flagellin protects against acute pneumococcal pneumonia in a TLR5-dependent and NLRC4-independent fashion.

    Science.gov (United States)

    Muñoz-Wolf, Natalia; Rial, Analía; Fougeron, Delphine; Tabareau, Julien; Sirard, Jean-Claude; Chabalgoity, José A

    2016-09-01

    To evaluate efficacy of sublingual flagellin to treat acute pneumonia. Mice were treated sublingually with flagellin and challenged intranasally with a lethal dose of pneumococcus. Flagellins lacking TLR5 or NLRC4 activation domains were used to assess their contribution to protection. Sublingual flagellin protected mice in a TLR5-dependent, NLRC4-independent fashion. Neutrophils were required for protection. Flagellin-stimulated lung epithelial cells recapitulated the lung's transcriptional profile suggesting they could be targeted by flagellin in vivo. Ligation of TLR5, a pathogen recognition receptor not naturally engaged by pneumococcus, protects mice from invasive pneumonia when administered via sublingual route. This can be a highly cost-effective alternative therapy against pneumonia.

  12. Immunogenicity investigations of lipidoid structures in vitro and in silico: Modulating lipidoid-mediated TLR4 activation by nanoparticle design

    DEFF Research Database (Denmark)

    de Groot, Anne Marit; Thanki, Kaushik; Gangloff, Monique

    2018-01-01

    , we showed that encapsulation of siRNA in lipid-polymer hybrid nanoparticles (LPNs), based on poly(DL-lactic-co-glycolic acid) (PLGA) and cationic lipid-like materials (lipidoids), remarkably enhances intracellular delivery of siRNA as compared to siRNA delivery with LPNs modified...... acid lipid particles, which was the reference formulation for siRNA delivery, proved to activate TLR4. However, by combining lipidoids with PLGA into LPNs, TLR4 activation was abrogated. Thus, lipidoid-mediated TLR4 activation during siRNA delivery may be modulated via optimization of the formulation......Therapeutics based on small interfering RNA (siRNA) have promising potential as antiviral and anti-inflammatory agents. To deliver siRNA across cell membranes to reach the RNA interference pathway in the cytosol of target cells, non-viral nanoparticulate delivery approaches are explored. Recently...

  13. The TLR2 Antagonist Staphylococcal Superantigen-Like Protein 3 Acts as a Virulence Factor to Promote Bacterial Pathogenicity in vivo

    NARCIS (Netherlands)

    Koymans, Kirsten J.; Goldmann, Oliver; Karlsson, Christofer A.Q.; Sital, Wiedjai; Thänert, Robert; Bisschop, Adinda; Vrieling, Manouk; Malmström, Johan; van Kessel, Kok P M; De Haas, Carla J.C.; Van Strijp, Jos A.G.; Medina, Eva

    2017-01-01

    Toll-like receptor (TLR) signaling is important in the initiation of immune responses and subsequent instigation of adaptive immunity. TLR2 recognizes bacterial lipoproteins and plays a central role in the host defense against bacterial infections, including those caused by Staphylococcus aureus.

  14. Ginkgolide B Suppresses TLR4-Mediated Inflammatory Response by Inhibiting the Phosphorylation of JAK2/STAT3 and p38 MAPK in High Glucose-Treated HUVECs

    Directory of Open Access Journals (Sweden)

    Kun Chen

    2017-01-01

    Full Text Available Aim. Ginkgolide B is a Ginkgo biloba leaf extract that has been identified as a natural platelet-activating factor receptor (PAFR antagonist. We investigated the effect of ginkgolide B on high glucose-induced TLR4 activation in human umbilical vein endothelial cells (HUVECs. Methods. Protein expression was analyzed by immunoblotting. Small-interfering RNA (siRNA was used to knock down PAFR and TLR4 expression. Results. Ginkgolide B suppressed the expression of TLR4 and MyD88 that was induced by high glucose. Ginkgolide B also reduced the levels of platelet endothelial cell adhesion molecule-1, interleukin-6, and monocyte chemotactic protein 1. Further, we examined the association between PAFR and TLR4 by coimmunoprecipitation. The result showed that high glucose treatment caused the binding of PAFR and TLR4, whereas ginkgolide B abolished this binding. The functional analysis indicated that PAFR siRNA treatment reduced TLR4 expression, and TLR4 siRNA treatment decreased PAFR expression in high glucose-treated HUVECs, further supporting the coimmunoprecipitation data. Ginkgolide B inhibited the phosphorylation of Janus kinase 2 (JAK2/signal transducer and activator of transcription 3 (STAT3 and p38 mitogen-activated protein kinase (MAPK. Conclusion. Ginkgolide B exerted protective effects by inhibiting the TLR4-mediated inflammatory response in high glucose-treated endothelial cells. The mechanism of action of ginkgolide B might be associated with inhibition of the JAK2/STAT3 and p38 MAPK phosphorylation.

  15. TLR3 mediates release of IL-1β and cell death in keratinocytes in a caspase-4 dependent manner.

    Science.gov (United States)

    Grimstad, Øystein; Husebye, Harald; Espevik, Terje

    2013-10-01

    Inflammation and timely cell death are important elements in host defence and healing processes. Keratinocytes express high levels of Toll-like receptor 3 (TLR3), and stimulation of the receptor with its ligand polyinosinic-polycytidylic acid (polyI:C) is a powerful signal for release of a variety of proinflammatory cytokines. Caspase-4 is required for maturation of pro-IL-1β through activation of caspase-1 in keratinocytes. TLR3 in keratinocytes was stimulated with polyI:C. Induction of messenger RNA of pro-IL-1β and inflammasomal components was measured using quantitative polymerase chain reaction methodology. Protein expression of IL-1β was analysed with ELISA and Western blot techniques. Activation of apoptotic caspases was measured with flow cytometry, and cytotoxicity was determined. TLR3 induced release of substantial amounts of pro-IL-1β in keratinocytes. NLRP3 or ASC dependent processing of IL-1β into its cleaved bioactive form was found to be minimal. The release of IL-1β was due to polyI:C induced cell death that occurred through a caspase-4 dependent manner. Caspase-1 did not seem to be involved in the polyI:C induced cytotoxicity despite that TLR3 stimulation induced activation of caspase-1. In addition, the apoptotic caspases -8, -9 and -3/7 were activated by polyI:C. TLR3 stimulation in keratinocytes induces a caspase-4 dependent release of pro-IL-1β, but further processing to active IL-1β is limited. Furthermore, TLR3 stimulation results in pyroptotic- and apoptotic cell death. Copyright © 2013 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.

  16. TLR2-dependent inhibition of macrophage responses to IFN-gamma is mediated by distinct, gene-specific mechanisms.

    Directory of Open Access Journals (Sweden)

    Sarah A Benson

    2009-07-01

    Full Text Available Mycobacterium tuberculosis uses multiple mechanisms to avoid elimination by the immune system. We have previously shown that M. tuberculosis can inhibit selected macrophage responses to IFN-gamma through TLR2-dependent and -independent mechanisms. To specifically address the role of TLR2 signaling in mediating this inhibition, we stimulated macrophages with the specific TLR2/1 ligand Pam(3CSK(4 and assayed responses to IFN-gamma. Pam(3CSK(4 stimulation prior to IFN-gamma inhibited transcription of the unrelated IFN-gamma-inducible genes, CIITA and CXCL11. Surface expression of MHC class II and secretion of CXCL11 were greatly reduced as well, indicating that the reduction in transcripts had downstream effects. Inhibition of both genes required new protein synthesis. Using chromatin immunoprecipitation, we found that TLR2 stimulation inhibited IFN-gamma-induced RNA polymerase II binding to the CIITA and CXCL11 promoters. Furthermore, TATA binding protein was unable to bind the TATA box of the CXCL11 promoter, suggesting that assembly of transcriptional machinery was disrupted. However, TLR2 stimulation affected chromatin modifications differently at each of the inhibited promoters. Histone H3 and H4 acetylation was reduced at the CIITA promoter but unaffected at the CXCL11 promoter. In addition, NF-kappaB signaling was required for inhibition of CXCL11 transcription, but not for inhibition of CIITA. Taken together, these results indicate that TLR2-dependent inhibition of IFN-gamma-induced gene expression is mediated by distinct, gene-specific mechanisms that disrupt binding of the transcriptional machinery to the promoters.

  17. Interaction of TLR-IFN and HLA polymorphisms on susceptibility of chronic HBV infection in Southwest Han Chinese.

    Science.gov (United States)

    He, Dengming; Tao, Shiqi; Guo, Shimin; Li, Maoshi; Wu, Junqiu; Huang, Hongfei; Guo, Xinwu; Yan, Guohua; Zhu, Peng; Wang, Yuming

    2015-08-01

    The toll-like receptor-interferon (TLR-IFN) signalling pathway plays a crucial role in HBV infection. Human leucocyte antigen (HLA) polymorphisms are associated with chronic HBV infection by genome wide association study (GWAS). We aimed to explore interaction between TLR-IFN and HLA gene polymorphisms in susceptibility of chronic HBV infection. In the Chinese Southwest Han population, 1191 chronic HBV infection patients and 273 HBV clearance were selected. A total of 39 single nucleotide polymorphism loci in 23 genes of the TLR-IFN pathway and four HLA polymorphism loci associated with chronic HBV infection identified by GWAS were selected for genotyping. SNPStats, QVALUE, and multifactor dimensionality reduction were used for statistical analysis. A significant association was seen in several of the TLR-IFN pathway genes, TLR9 rs352140 (OR = 0.70, P = 0.0088), IL1B rs16944 (OR = 0.67, P = 0.016), IL12B rs3212227 (OR = 1.38, P = 0.021), IFNGR1 rs3799488 (OR = 1.48, P = 0.0048), IFNGR2 rs1059293 (OR = 0.27, P = 0.011), MX1 rs467960 (OR = 0.68, P = 0.022), as well as four loci in HLA, rs3077 (OR = 0.55, P rs16944 (0.13%), rs1143623 and rs6613 (0.10%). The combination of rs9277535 in HLA and rs16944 in IL1B was the best model to predict chronic HBV infection (testing accuracy = 0.6040, P = 0.0010, cross-validation consistency = 10/10). TLR-IFN pathway gene polymorphisms are associated with chronic HBV infection. Interactions with polymorphisms in these genes may be one mechanism by which HLA polymorphisms influence susceptibility to chronic HBV infection, as specific single nucleotide polymorphism combinations are highly predictive of chronic HBV infection. © 2014 The Authors. Liver International Published by John Wiley & Sons Ltd.

  18. [Effect of resveratrol on expression of TLR4 and inflammatory factors in gingival epithelial cells under high glucose environment].

    Science.gov (United States)

    Lv, Jia-Shu; Jiang, Xue-Wei; Zhang, Yan; Zhen, Lei

    2017-02-01

    Through a study of the molecular mechanism of the effect of resveratrol(RSV) on expression of TLR4 and inflammatory factors in gingival epithelial cells under high glucose environment, the therapeutic effect and molecular mechanism of resveratrol on periodontitis in patients with diabetes mellitus was investigated. Gingival epithelial cells were cultured in vitro; according to the way of action, the cultured cells were divided into control group, high glucose group(HG) and HG+RSV group. The mRNA expression of TLR4 was detected by PCR; The third generation of gingival epithelial cells were pre-treated with or without RSV for 24 h under high glucose conditions, and subsequently treated with LPS at 100 ng/mL for 2 h. ELISA was used to detect the secretion of IL-1 beta, IL-6, IL-8 and TNF- alpha; the activation of TLR4 downstream signaling molecules NF-κB p65, p38 MAPK, and STAT3 was determined by Western blot. SPSS17.0 software package was used for statistical analysis. RSV could reverse the increase of TLR4 level in gingival epithelial cells in high glucose medium.LPS markedly increased the expression and secretion of IL-1β, IL-6, IL-8, and TNF-α in GECs cultured in high glucose medium, which was partly blocked in the presence of RSV. Furthermore, Western blot results showed that RSV significantly suppressed the phosphorylation of TLR4 downstream factors NF-κB p65, p38MAPK, and STAT3. RSV reduces inflammatory cytokine secretion in gingival epithelial cells, through negative regulation of TLR4 signaling pathway.

  19. TLR3 signaling is either protective or pathogenic for the development of Theiler's virus-induced demyelinating disease depending on the time of viral infection

    Directory of Open Access Journals (Sweden)

    Jin Young-Hee

    2011-12-01

    Full Text Available Abstract Background We have previously shown that toll-like receptor 3 (TLR3-mediated signaling plays an important role in the induction of innate cytokine responses to Theiler's murine encephalomyelitis virus (TMEV infection. In addition, cytokine levels produced after TMEV infection are significantly higher in the glial cells of susceptible SJL mice compared to those of resistant C57BL/6 mice. However, it is not known whether TLR3-mediated signaling plays a protective or pathogenic role in the development of demyelinating disease. Methods SJL/J and B6;129S-Tlr3tm1Flv/J (TLR3KO-B6 mice, and TLR3KO-SJL mice that TLR3KO-B6 mice were backcrossed to SJL/J mice for 6 generations were infected with Theiler's murine encephalomyelitis virus (2 × 105 PFU with or without treatment with 50 μg of poly IC. Cytokine production and immune responses in the CNS and periphery of infected mice were analyzed. Results We investigated the role of TLR3-mediated signaling in the protection and pathogenesis of TMEV-induced demyelinating disease. TLR3KO-B6 mice did not develop demyelinating disease although they displayed elevated viral loads in the CNS. However, TLR3KO-SJL mice displayed increased viral loads and cellular infiltration in the CNS, accompanied by exacerbated development of demyelinating disease, compared to the normal littermate mice. Late, but not early, anti-viral CD4+ and CD8+ T cell responses in the CNS were compromised in TLR3KO-SJL mice. However, activation of TLR3 with poly IC prior to viral infection also exacerbated disease development, whereas such activation after viral infection restrained disease development. Activation of TLR3 signaling prior to viral infection hindered the induction of protective IFN-γ-producing CD4+ and CD8+ T cell populations. In contrast, activation of these signals after viral infection improved the induction of IFN-γ-producing CD4+ and CD8+ T cells. In addition, poly IC-pretreated mice displayed elevated PDL-1 and

  20. Expression of TLR4 in Non-Small Cell Lung Cancer Is Associated with PD-L1 and Poor Prognosis in Patients Receiving Pulmonectomy

    Directory of Open Access Journals (Sweden)

    Xiubao Ren

    2017-04-01

    Full Text Available Currently, the effect of inflammation on tumorigenesis and progression has been widely noted. As a member of pattern recognition receptors, toll-like receptor 4 (TLR4 plays a pivotal role in tumor immune microenvironment and has been increasingly investigated. In the present study, we evaluated TLR4 expression and its association with programmed cell death ligand 1 (PD-L1 in non-small cell lung cancer (NSCLC tissues and assessed the predicting value of TLR4 on postoperative outcome. A total of 126 NSCLC patients receiving complete pulmonary resection and systematic lymph node dissection between April 2008 and August 2014 were enrolled. All the patients had integrated clinicopathological records and follow-up data. TLR4 and PD-L1 expression on NSCLC samples were determined by immunohistochemistry, and serum soluble TLR4 (sTLR4 levels were measured by enzyme-linked immunosorbent assay. Results showed that TLR4 expression level in cancer tissue was significantly higher than that in para-cancer tissue. Elevated TLR4 expression was significantly associated with histological type (adenocarcinoma higher than squamous cell carcinoma, P = 0.041, increased clinical TNM stage (P < 0.001, and presence of lymphatic invasion (P < 0.001. Besides, TLR4 expression level in cancer samples was inversely correlated with serum sTLR4 level in patients with early-stage NSCLC (r = −0.485, P = 0.003. TLR4 expression level was also positively correlated with the PD-L1 expression level (r = 0.545, P < 0.0001. Multivariate analysis showed that expression level of TLR4 was an independent prognostic factor and TLR4 overexpression indicated a poor overall survival and disease-free survival. Taken together, we conclude that expression of TLR4 in lung cancer is associated with PD-L1 and could predict the outcome of patients with NSCLC receiving pulmonary resection for cancer.

  1. Genetic Variation in the TLR5 Locus Is Associated with Anti-TNF Response Among Rheumatoid Arthritis Patients

    DEFF Research Database (Denmark)

    Sode, Jacob

    2014-01-01

    and interferon-gamma pathways were assessed in 538 anti-TNF naive Danish RA patients. Prospectively collected clinical data including functional status (HAQ), patient global score, smoking status, tender and swollen joint counts, treatments, rheumatoid factor (RF) status and C-reative protein (CRP) were obtained...... for seropositive RA in CARD8 (rs2043211), IL18 (rs187238) and TLR1 (rs4833095) (data not shown) but due to low power these results are preliminary. Conclusion: Our results confirm association between a TLR5 locus and EULAR response to anti-TNF treatment. Previous studies suggest that this polymorphism...

  2. Association of TLR variants with susceptibility to Plasmodium vivax malaria and parasitemia in the Amazon region of Brazil.

    Science.gov (United States)

    Costa, Allyson Guimarães; Ramasawmy, Rajendranath; Ibiapina, Hiochelson Najibe Santos; Sampaio, Vanderson Souza; Xábregas, Lilyane Amorim; Brasil, Larissa Wanderley; Tarragô, Andréa Monteiro; Almeida, Anne Cristine Gomes; Kuehn, Andrea; Vitor-Silva, Sheila; Melo, Gisely Cardoso; Siqueira, André Machado; Monteiro, Wuelton Marcelo; Lacerda, Marcus Vinicius Guimarães; Malheiro, Adriana

    2017-01-01

    Plasmodium vivax malaria (Pv-malaria) is still considered a neglected disease despite an alarming number of individuals being infected annually. Malaria pathogenesis occurs with the onset of the vector-parasite-host interaction through the binding of pathogen-associated molecular patterns (PAMPs) and receptors of innate immunity, such as toll-like receptors (TLRs). The triggering of the signaling cascade produces an elevated inflammatory response. Genetic polymorphisms in TLRs are involved in susceptibility or resistance to infection, and the identification of genes involved with Pv-malaria response is important to elucidate the pathogenesis of the disease and may contribute to the formulation of control and elimination tools. A retrospective case-control study was conducted in an intense transmission area of Pv-malaria in the state of Amazonas, Brazil. Genetic polymorphisms (SNPs) in different TLRs, TIRAP, and CD14 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in 325 patients infected with P. vivax and 274 healthy individuals without malaria history in the prior 12 months from the same endemic area. Parasite load was determined by qPCR. Simple and multiple logistic/linear regressions were performed to investigate association between the polymorphisms and the occurrence of Pv-malaria and parasitemia. The C/T (TLR5 R392StopCodon) and T/T (TLR9 -1486C/T) genotypes appear to be risk factors for infection by P. vivax (TLR5: C/C vs. C/T [OR: 2.116, 95% CI: 1.054-4.452, p = 0.031]; TLR9: C/C vs. T/T [OR: 1.919, 95% CI: 1.159-3.177, p = 0.010]; respectively). Fever (COEF = 7599.46, 95% CI = 3063.80-12135.12, p = 0.001) and the C/C genotype of TLR9 -1237C/T (COEF = 17006.63, 95% CI = 3472.83-30540.44, p = 0.014) were independently associated with increased parasitemia in patients with Pv-malaria. Variants of TLRs may predispose individuals to infection by P. vivax. The TLR5 R392StopCodon and TLR9 -1486C/T variants

  3. Association of TLR variants with susceptibility to Plasmodium vivax malaria and parasitemia in the Amazon region of Brazil.

    Directory of Open Access Journals (Sweden)

    Allyson Guimarães Costa

    Full Text Available Plasmodium vivax malaria (Pv-malaria is still considered a neglected disease despite an alarming number of individuals being infected annually. Malaria pathogenesis occurs with the onset of the vector-parasite-host interaction through the binding of pathogen-associated molecular patterns (PAMPs and receptors of innate immunity, such as toll-like receptors (TLRs. The triggering of the signaling cascade produces an elevated inflammatory response. Genetic polymorphisms in TLRs are involved in susceptibility or resistance to infection, and the identification of genes involved with Pv-malaria response is important to elucidate the pathogenesis of the disease and may contribute to the formulation of control and elimination tools.A retrospective case-control study was conducted in an intense transmission area of Pv-malaria in the state of Amazonas, Brazil. Genetic polymorphisms (SNPs in different TLRs, TIRAP, and CD14 were genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP analysis in 325 patients infected with P. vivax and 274 healthy individuals without malaria history in the prior 12 months from the same endemic area. Parasite load was determined by qPCR. Simple and multiple logistic/linear regressions were performed to investigate association between the polymorphisms and the occurrence of Pv-malaria and parasitemia. The C/T (TLR5 R392StopCodon and T/T (TLR9 -1486C/T genotypes appear to be risk factors for infection by P. vivax (TLR5: C/C vs. C/T [OR: 2.116, 95% CI: 1.054-4.452, p = 0.031]; TLR9: C/C vs. T/T [OR: 1.919, 95% CI: 1.159-3.177, p = 0.010]; respectively. Fever (COEF = 7599.46, 95% CI = 3063.80-12135.12, p = 0.001 and the C/C genotype of TLR9 -1237C/T (COEF = 17006.63, 95% CI = 3472.83-30540.44, p = 0.014 were independently associated with increased parasitemia in patients with Pv-malaria.Variants of TLRs may predispose individuals to infection by P. vivax. The TLR5 R392StopCodon and TLR9 -1486C

  4. DMPD: Pellino proteins: novel players in TLR and IL-1R signalling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17635639 Pellino proteins: novel players in TLR and IL-1R signalling. Schauvliege R..., Janssens S, Beyaert R. J Cell Mol Med. 2007 May-Jun;11(3):453-61. (.png) (.svg) (.html) (.csml) Show Pellino proteins: novel player...s in TLR and IL-1R signalling. PubmedID 17635639 Title Pellino proteins: novel player...tml) CSML File (.csml) Open .csml file with CIOPlayer Open .csml file with CIOPlayer - ※CIO Playerのご利用上の注意 Open .csml file with CIO Open .csml file with CIO - ※CIOのご利用上の注意 ...

  5. REGULATION OF TLR/RLR GENE ACTIVITY AND SYNTHESIS OF CYTOKINES DURING PHORBOL MYRISTATE ACETATE (PMA-INDUCED DIFFERENTIATION OF THP-1 MONOCYTES INTO MACROPHAGE-LIKE CELLS

    Directory of Open Access Journals (Sweden)

    T. M. Sokolova

    2017-01-01

    Full Text Available The levels of TLR/RLR gene expression and production of some cytokines were studied in monocytic THP-1 cell line during its differentiation to mature macrophage-like forms induced by phorbol 12-myristate 13-acetate (PMA treatment for 1 and 5 days in vitro. For the first time, we have shown high induction levels for the genes that encode signaling immune receptors and transcription factors in response to PMA, as well as inhibitory effects of TLR3, TLR7/TLR8, TLR9-agonists in mature macrophages. The PMAactivated THP-1 macrophage-like cells secreted large quantitities of inflammatory IL-1β and TNFα cytokines into culture medium.

  6. Andrographolide Suppress Tumor Growth by Inhibiting TLR4/NF-κB Signaling Activation in Insulinoma

    Science.gov (United States)

    Zhang, Qian-Qian; Ding, Yi; Lei, Yan; Qi, Cui-Ling; He, Xiao-Dong; Lan, Tian; Li, Jiang-Chao; Gong, Ping; Yang, Xuesong; Geng, Jian-Guo; Wang, Li-Jing

    2014-01-01

    Insulinomas are rare tumors, and approximately 10% of insulinomas are malignant. Accumulating evidence has implicated that we still lack effective therapy to treat the patients who are diagnosed with rare malignant insulinoma. Previous studies have reported that Andrographolide (Andro) could inhibit cell cycle progression, reduce cell invasion and induce cell apoptosis in many common cancer cells. However, the effects of andro are cell type-dependent. So we emplored the β-TC-6 cells and the RIP1-Tag2 transgenic mouse model of endogenously growing insulinoma model to elucidate the possible anti-cancer effect of Andro on insulinoma, an uncommon type of malignant cancers in this study. Our experiments revealed that Andro significantly inhibited tumor growth at both the early-stage and the advanced-stage of insulinoma through targeting the TLR4/NF-κB signaling pathway. This work initially provides the evidence that the TLR4/NF-κB signaling pathway might be vital as a potential therapeutic target, and also indispensable in Andro-mediated anti-cancer effect in insulinoma. PMID:24719558

  7. CD40 signaling synergizes with TLR-2 in the BCR independent activation of resting B cells.

    Directory of Open Access Journals (Sweden)

    Shweta Jain

    Full Text Available Conventionally, signaling through BCR initiates sequence of events necessary for activation and differentiation of B cells. We report an alternative approach, independent of BCR, for stimulating resting B (RB cells, by involving TLR-2 and CD40--molecules crucial for innate and adaptive immunity. CD40 triggering of TLR-2 stimulated RB cells significantly augments their activation, proliferation and differentiation. It also substantially ameliorates the calcium flux, antigen uptake capacity and ability of B cells to activate T cells. The survival of RB cells was improved and it increases the number of cells expressing activation induced deaminase (AID, signifying class switch recombination (CSR. Further, we also observed increased activation rate and decreased threshold period required for optimum stimulation of RB cells. These results corroborate well with microarray gene expression data. This study provides novel insights into coordination between the molecules of innate and adaptive immunity in activating B cells, in a BCR independent manner. This strategy can be exploited to design vaccines to bolster B cell activation and antigen presenting efficiency, leading to faster and better immune response.

  8. CD40 signaling synergizes with TLR-2 in the BCR independent activation of resting B cells.

    Science.gov (United States)

    Jain, Shweta; Chodisetti, Sathi Babu; Agrewala, Javed N

    2011-01-01

    Conventionally, signaling through BCR initiates sequence of events necessary for activation and differentiation of B cells. We report an alternative approach, independent of BCR, for stimulating resting B (RB) cells, by involving TLR-2 and CD40--molecules crucial for innate and adaptive immunity. CD40 triggering of TLR-2 stimulated RB cells significantly augments their activation, proliferation and differentiation. It also substantially ameliorates the calcium flux, antigen uptake capacity and ability of B cells to activate T cells. The survival of RB cells was improved and it increases the number of cells expressing activation induced deaminase (AID), signifying class switch recombination (CSR). Further, we also observed increased activation rate and decreased threshold period required for optimum stimulation of RB cells. These results corroborate well with microarray gene expression data. This study provides novel insights into coordination between the molecules of innate and adaptive immunity in activating B cells, in a BCR independent manner. This strategy can be exploited to design vaccines to bolster B cell activation and antigen presenting efficiency, leading to faster and better immune response.

  9. Pimecrolimus enhances TLR2/6-induced expression of antimicrobial peptides in keratinocytes.

    Science.gov (United States)

    Büchau, Amanda S; Schauber, Jürgen; Hultsch, Thomas; Stuetz, Anton; Gallo, Richard L

    2008-11-01

    Calcineurin inhibitors are potent inhibitors of T-cell-receptor mediated activation of the adaptive immune system. The effects of this class of drug on the innate immune response system are not known. Keratinocytes are essential to innate immunity in skin and rely on toll-like receptors (TLRs) and antimicrobial peptides to appropriately recognize and respond to injury or microbes. In this study we examined the response of cultured human keratinocytes to pimecrolimus. We observed that pimecrolimus enhances distinct expression of cathelicidin, CD14, and human beta-defensin-2 and beta-defensin-3 in response to TLR2/6 ligands. Some of these responses were further enhanced by 1,25 vitamin D3. Pimecrolimus also increased the functional capacity of keratinocytes to inhibit growth of Staphylococcus aureus and decreased TLR2/6-induced expression of IL-10 and IL-1beta. Furthermore, pimecrolimus inhibited nuclear translocation of NFAT and NF-kappaB in keratinocytes. These observations uncover a previously unreported function for pimecrolimus in cutaneous innate host defense.

  10. TNF is required for TLR ligand-mediated but not protease-mediated allergic airway inflammation.

    Science.gov (United States)

    Whitehead, Gregory S; Thomas, Seddon Y; Shalaby, Karim H; Nakano, Keiko; Moran, Timothy P; Ward, James M; Flake, Gordon P; Nakano, Hideki; Cook, Donald N

    2017-09-01

    Asthma is associated with exposure to a wide variety of allergens and adjuvants. The extent to which overlap exists between the cellular and molecular mechanisms triggered by these various agents is poorly understood, but it might explain the differential responsiveness of patients to specific therapies. In particular, it is unclear why some, but not all, patients benefit from blockade of TNF. Here, we characterized signaling pathways triggered by distinct types of adjuvants during allergic sensitization. Mice sensitized to an innocuous protein using TLR ligands or house dust extracts as adjuvants developed mixed eosinophilic and neutrophilic airway inflammation and airway hyperresponsiveness (AHR) following allergen challenge, whereas mice sensitized using proteases as adjuvants developed predominantly eosinophilic inflammation and AHR. TLR ligands, but not proteases, induced TNF during allergic sensitization. TNF signaled through airway epithelial cells to reprogram them and promote Th2, but not Th17, development in lymph nodes. TNF was also required during the allergen challenge phase for neutrophilic and eosinophilic inflammation. In contrast, TNF was dispensable for allergic airway disease in a protease-mediated model of asthma. These findings might help to explain why TNF blockade improves lung function in only some patients with asthma.

  11. Lipopolysaccharides with acylation defects potentiate TLR4 signaling and shape T cell responses.

    Directory of Open Access Journals (Sweden)

    Anna Martirosyan

    Full Text Available Lipopolysaccharides or endotoxins are components of Gram-negative enterobacteria that cause septic shock in mammals. However, a LPS carrying hexa-acyl lipid A moieties is highly endotoxic compared to a tetra-acyl LPS and the latter has been considered as an antagonist of hexa-acyl LPS-mediated TLR4 signaling. We investigated the relationship between the structure and the function of bacterial LPS in the context of human and mouse dendritic cell activation. Strikingly, LPS with acylation defects were capable of triggering a strong and early TLR4-dependent DC activation, which in turn led to the activation of the proteasome machinery dampening the pro-inflammatory cytokine secretion. Upon activation with tetra-acyl LPS both mouse and human dendritic cells triggered CD4(+ T and CD8(+ T cell responses and, importantly, human myeloid dendritic cells favored the induction of regulatory T cells. Altogether, our data suggest that LPS acylation controlled by pathogenic bacteria might be an important strategy to subvert adaptive immunity.

  12. The TLR5 ligand flagellin promotes asthma by priming allergic responses to indoor allergens

    Science.gov (United States)

    Wilson, Rhonda H.; Maruoka, Shuichiro; Whitehead, Gregory S.; Foley, Julie F.; Flake, Gordon P.; Sever, Michelle L.; Zeldin, Darryl C.; Kraft, Monica; Garantziotis, Stavros; Nakano, Hideki; Cook, Donald N.

    2012-01-01

    Allergic asthma is a complex disease characterized by eosinophilic pulmonary inflammation, mucus production and reversible airway obstruction1. Exposure to indoor allergens is a clear risk factor for asthma, but this disease is also associated with high household levels of total and Gram-negative bacteria2. The ability of bacterial products to act as adjuvants3 suggests they might promote asthma by priming allergic sensitization to inhaled allergens. In support of this idea, house dust extracts (HDEs) can activate antigen presenting dendritic cells (DC) in vitro and promote allergic sensitization to inhaled innocuous proteinsin vivo4. It is unknown which microbial products provide most of the adjuvant activity in HDEs. A screen of microbial products for their adjuvant activity in the airway revealed that the bacterial protein, flagellin (FLA) stimulated strong allergic responses to an innocuous inhaled protein. Moreover, toll-like receptor (TLR)5, the mammalian receptor for FLA5,6, was required for priming strong allergic responses to natural indoor allergens present in HDEs. In addition, the incidence of human asthma was associated with high serum levels of FLA-specific antibodies. Together, these findings suggest that household FLA promotes the development of allergic asthma by TLR5-dependent priming of allergic responses to indoor allergens. PMID:23064463

  13. Neonatal plasma polarizes TLR4-mediated cytokine responses towards low IL-12p70 and high IL-10 production via distinct factors.

    Directory of Open Access Journals (Sweden)

    Mirjam E Belderbos

    Full Text Available Human neonates are highly susceptible to infection, which may be due in part to impaired innate immune function. Neonatal Toll-like receptor (TLR responses are biased against the generation of pro-inflammatory/Th1-polarizing cytokines, yet the underlying mechanisms are incompletely defined. Here, we demonstrate that neonatal plasma polarizes TLR4-mediated cytokine production. When exposed to cord blood plasma, mononuclear cells (MCs produced significantly lower TLR4-mediated IL-12p70 and higher IL-10 compared to MC exposed to adult plasma. Suppression by neonatal plasma of TLR4-mediated IL-12p70 production, but not induction of TLR4-mediated IL-10 production, was maintained up to the age of 1 month. Cord blood plasma conferred a similar pattern of MC cytokine responses to TLR3 and TLR8 agonists, demonstrating activity towards both MyD88-dependent and MyD88-independent agonists. The factor causing increased TLR4-mediated IL-10 production by cord blood plasma was heat-labile, lost after protein depletion and independent of lipoprotein binding protein (LBP or soluble CD14 (sCD14. The factor causing inhibition of TLR4-mediated IL-12p70 production by cord blood plasma was resistant to heat inactivation or protein depletion and was independent of IL-10, vitamin D and prostaglandin E2. In conclusion, human neonatal plasma contains at least two distinct factors that suppress TLR4-mediated IL-12p70 production or induce IL-10 or production. Further identification of these factors will provide insight into the ontogeny of innate immune development and might identify novel targets for the prevention and treatment of neonatal infection.

  14. Neonatal Plasma Polarizes TLR4-Mediated Cytokine Responses towards Low IL-12p70 and High IL-10 Production via Distinct Factors

    Science.gov (United States)

    Belderbos, Mirjam E.; Levy, Ofer; Stalpers, Femke; Kimpen, Jan L.; Meyaard, Linde; Bont, Louis

    2012-01-01

    Human neonates are highly susceptible to infection, which may be due in part to impaired innate immune function. Neonatal Toll-like receptor (TLR) responses are biased against the generation of pro-inflammatory/Th1-polarizing cytokines, yet the underlying mechanisms are incompletely defined. Here, we demonstrate that neonatal plasma polarizes TLR4-mediated cytokine production. When exposed to cord blood plasma, mononuclear cells (MCs) produced significantly lower TLR4-mediated IL-12p70 and higher IL-10 compared to MC exposed to adult plasma. Suppression by neonatal plasma of TLR4-mediated IL-12p70 production, but not induction of TLR4-mediated IL-10 production, was maintained up to the age of 1 month. Cord blood plasma conferred a similar pattern of MC cytokine responses to TLR3 and TLR8 agonists, demonstrating activity towards both MyD88-dependent and MyD88-independent agonists. The factor causing increased TLR4-mediated IL-10 production by cord blood plasma was heat-labile, lost after protein depletion and independent of lipoprotein binding protein (LBP) or soluble CD14 (sCD14). The factor causing inhibition of TLR4-mediated IL-12p70 production by cord blood plasma was resistant to heat inactivation or protein depletion and was independent of IL-10, vitamin D and prostaglandin E2. In conclusion, human neonatal plasma contains at least two distinct factors that suppress TLR4-mediated IL-12p70 production or induce IL-10 or production. Further identification of these factors will provide insight into the ontogeny of innate immune development and might identify novel targets for the prevention and treatment of neonatal infection. PMID:22442690

  15. Lipopolysaccharide-induced inhibition of transcription of tlr4 in vitro is reversed by dexamethasone and correlates with presence of conserved NFκB binding sites

    Energy Technology Data Exchange (ETDEWEB)

    Bonin, Camila P., E-mail: mila_bonin@yahoo.com.br [Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-900 (Brazil); Baccarin, Raquel Y.A., E-mail: baccarin@usp.br [Department of Clinics, School of Veterinary Medicine, University of São Paulo, São Paulo 05508-900 (Brazil); Nostell, Katarina, E-mail: katarina.nostell@slu.se [Department of Clinical Sciences, Swedish University of Agricultural Sciences, Box 7054, 750 07 Uppsala (Sweden); Nahum, Laila A., E-mail: laila@nahum.com.br [Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte 30190-002 (Brazil); Faculdade Infórium de Tecnologia, Belo Horizonte 30130-180 (Brazil); Fossum, Caroline, E-mail: caroline.fossum@bvf.slu.se [Department of Biomedicine and Veterinary Public Health, Section for Immunology, Swedish University of Agricultural Sciences, BMC, Box 588, SE 751 23 Uppsala (Sweden); Camargo, Maristela M. de, E-mail: mmcamar@usp.br [Department of Immunology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-900 (Brazil)

    2013-03-08

    Highlights: ► Chimpanzees, horses and humans have regions of similarity on TLR4 and MD2 promoters. ► Rodents have few regions of similarity on TLR4 promoter when compared to primates. ► Conserved NFkB binding sites were found in the promoters of TLR4 and MD2. ► LPS-induced inhibition of TLR4 transcription is reversed by dexamethasone. ► LPS-induced transcription of MD2 is inhibited by dexamethasone. -- Abstract: Engagement of Tol