scholarly journals Maturation of Human Dendritic Cells by Cell Wall Skeleton of Mycobacterium bovis Bacillus Calmette-Guérin: Involvement of Toll-Like Receptors

2000 ◽  
Vol 68 (12) ◽  
pp. 6883-6890 ◽  
Author(s):  
Shoutaro Tsuji ◽  
Misako Matsumoto ◽  
Osamu Takeuchi ◽  
Shizuo Akira ◽  
Ichiro Azuma ◽  
...  
Keyword(s):  
Cell Wall ◽  
Dendritic Cells ◽  
Mycobacterium Bovis ◽  
Surface Expression ◽  
Necrosis Factor Alpha ◽  
Mycolic Acids ◽  
Tnf Α ◽  
Toll Like Receptor 2 ◽  
Factor Alpha ◽  
Human Dendritic Cells

ABSTRACT The constituents of mycobacteria are an effective immune adjuvant, as observed with complete Freund's adjuvant. In this study, we demonstrated that the cell wall skeleton of Mycobacterium bovis bacillus Calmette-Guérin (BCG-CWS), a purified noninfectious material consisting of peptidoglycan, arabinogalactan, and mycolic acids, induces maturation of human dendritic cells (DC). Surface expression of CD40, CD80, CD83, and CD86 was increased by BCG-CWS on human immature DC, and the effect was similar to those of interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-α), heat-killed BCG, and viable BCG. BCG-CWS induced the secretion of TNF-α, IL-6, and IL-12 p40. CD83 expression was increased by a soluble factor secreted from BCG-CWS-treated DC and was completely inhibited by monoclonal antibodies against TNF-α. BCG-CWS-treated DC stimulated extensive allogeneic mixed lymphocyte reactions. The level of TNF-α secreted through BCG-CWS was partially suppressed in murine macrophages with no Toll-like receptor 2 (TLR 2) or TLR4 and was completely lost in TLR2 and TLR4 double-deficient macrophages. These results suggest that the BCG-CWS induces TNF-α secretion from DC via TLR2 and TLR4 and that the secreted TNF-α induces the maturation of DC per se.

scholarly journals Interaction of Neisseria meningitidis with Human Dendritic Cells

2001 ◽  
Vol 69 (11) ◽  
pp. 6912-6922 ◽  
Author(s):  
Annette Kolb-Mäurer ◽  
Alexandra Unkmeir ◽  
Ulrike Kämmerer ◽  
Claudia Hübner ◽  
Thomas Leimbach ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Neisseria Meningitidis ◽  
Proinflammatory Cytokines ◽  
Interleukin 1 ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Cytokine Levels ◽  
Factor Alpha ◽  
Human Dendritic Cells ◽  
Necrosis Factor

ABSTRACT Infection with Neisseria meningitidis serogroup B is responsible for fatal septicemia and meningococcal meningitis. The severity of disease directly correlates with the production of the proinflammatory cytokines tumor necrosis factor alpha (TNF-α), interleukin-1 (IL-1), IL-6, and IL-8. However, the source of these cytokines has not been clearly defined yet. Since bacterial infection involves the activation of dendritic cells (DCs), we analyzed the interaction of N. meningitidis with monocyte-derived DCs. Using N. meningitidis serogroup B wild-type and unencapsulated bacteria, we found that capsule expression significantly impaired neisserial adherence to DCs. In addition, phagocytic killing of the bacteria in the phagosome is reduced by at least 10- to 100-fold. However, all strains induced strong secretion of proinflammatory cytokines TNF-α, IL-6, and IL-8 by DCs (at least 1,000-fold at 20 h postinfection [p.i.]), with significantly increased cytokine levels being measurable by as early as 6 h p.i. Levels of IL-1β, in contrast, were increased only 200- to 400-fold at 20 h p.i. with barely measurable induction at 6 h p.i. Moreover, comparable amounts of cytokines were induced by bacterium-free supernatants of Neisseria cultures containing neisserial lipooligosaccharide as the main factor. Our data suggest that activated DCs may be a significant source of high levels of proinflammatory cytokines in neisserial infection and thereby may contribute to the pathology of meningococcal disease.

scholarly journals Transient Neutralization of Tumor Necrosis Factor Alpha Can Produce a Chronic Fungal Infection in an Immunocompetent Host: Potential Role of Immature Dendritic Cells

2005 ◽  
Vol 73 (1) ◽  
pp. 39-49 ◽  
Author(s):  
Amy C. Herring ◽  
Nicole R. Falkowski ◽  
Gwo-Hsiao Chen ◽  
Rod A. McDonald ◽  
Galen B. Toews ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
Fungal Infection ◽  
Immune Deviation ◽  
Immunocompetent Host ◽  
Necrosis Factor Alpha ◽  
Immature Dendritic Cells ◽  
Tnf Α ◽  
Factor Alpha ◽  
Ifn Γ ◽  
Necrosis Factor

ABSTRACT The mechanisms underlying induction of immune dysregulation and chronic fungal infection by a transient tumor necrosis factor alpha (TNF-α) deficiency remain to be defined. The objective of our studies was to determine the potential contribution of neutropenia and immature dendritic cells to the immune deviation. Administration of an anti-TNF-α monoclonal antibody at day 0 neutralized TNF-α only during the first week of a pulmonary Cryptococcus neoformans infection. Transient neutralization of TNF-α resulted in transient depression of interleukin-12 (IL-12), monocyte chemotactic protein 1 (MCP-1), and gamma interferon (IFN-γ) production but permanently impaired long-term clearance of the infection from the lungs even after the levels of these cytokines increased and a vigorous inflammatory response developed. Early neutrophil recruitment was defective in the absence of TNF-α. However, as demonstrated by neutrophil depletion studies, this did not account for the decrease in IL-12 and IFN-γ levels and did not play a role in establishing chronic pulmonary cryptococcal infection. Transient TNF-α neutralization also produced a deficiency in CD11c+ MHC II+ cells and IL-12 in the lymph nodes, potentially implicating a defect in mature dendritic cell trafficking. Transfer of cryptococcal antigen-pulsed immature dendritic cells into naïve mice prior to intratracheal challenge resulted in the development of a nonprotective immune response to C. neoformans that was similar to that observed in anti-TNF-α-treated mice (increased IL-4, IL-5, and IL-10 levels, pulmonary eosinophilia, and decreased clearance). Thus, stimulation of an antifungal response by immature dendritic cells can result in an immune deviation similar to that produced by transient TNF-α deficiency, identifying a new mechanism by which a chronic fungal infection can occur in an immunocompetent host.

scholarly journals Fimbriated Porphyromonas gingivalis Is More Efficient than Fimbria-Deficient P. gingivalis in Entering Human Dendritic Cells In Vitro and Induces an Inflammatory Th1 Effector Response

2004 ◽  
Vol 72 (3) ◽  
pp. 1725-1732 ◽  
Author(s):  
Ravi Jotwani ◽  
Christopher W. Cutler
Keyword(s):  
Dendritic Cells ◽  
Porphyromonas Gingivalis ◽  
Cell Metabolism ◽  
Necrosis Factor Alpha ◽  
Immature Dendritic Cells ◽  
Factor Alpha ◽  
Ifn Γ ◽  
Gingival Mucosa ◽  
Human Dendritic Cells

ABSTRACT Porphyromonas gingivalis is a fimbriated mucosal pathogen implicated in chronic periodontitis (CP). The fimbriae are required for invasion of the gingival mucosa and for induction of CP in animal models of periodontitis. CP is associated with infection of immature dendritic cells (DCs) by P. gingivalis in situ and with increased numbers of dermal DCs (DDCs) and mature DCs in the lamina propria. The role of fimbriae in gaining entry into human DCs and how this modulates the inflammatory and effector immune responses, however, have not been explored. To address this, we generated monocyte-derived DCs (MDDCs) in vitro which phenotypically and functionally resemble DDCs. We show here that virulent fimbriated P. gingivalis 381, in contrast to its fimbria-deficient mutant, P. gingivalis DPG3, efficiently gains entry to MDDCs in a manner dependent on active cell metabolism and cytoskeletal rearrangement. In addition, uptake of 381, unlike DPG3, induces DCs to undergo maturation, upregulate costimulatory molecules, and secrete inflammation cytokines interleukin-1β (IL-1β), IL-6, tumor necrosis factor alpha, IL-10, and IL-12. Moreover, MDDCs pulsed with 381 also stimulated a higher autologous mixed lymphocyte reaction and induced a Th1-type response, with gamma interferon (IFN-γ) being the main cytokine. Monocytes used as controls demonstrated fimbria-dependent uptake of 381 as well but produced low levels of inflammatory cytokines compared to MDDCs. When MDDCs were pulsed with recombinant fimbrillin of P. gingivalis (10 μg/ml), maturation of MDDCs was also induced; moreover, matured MDDCs induced proliferation of autologous CD4+ T cells and release of IFN-γ. Thus, these results establish the significance of P. gingivalis fimbriae in the uptake of P. gingivalis by MDDCs and in induction of immunostimulatory Th1 responses.

scholarly journals Haemophilus ducreyi Lipooligosaccharides Induce Expression of the Immunosuppressive Enzyme Indoleamine 2,3-Dioxygenase via Type I Interferons and Tumor Necrosis Factor Alpha in Human Dendritic Cells

2011 ◽  
Vol 79 (8) ◽  
pp. 3338-3347 ◽  
Author(s):  
Wei Li ◽  
Barry P. Katz ◽  
Stanley M. Spinola
Keyword(s):  
Dendritic Cells ◽  
Tumor Necrosis ◽  
Treg Cells ◽  
Type I Interferons ◽  
Type I ◽  
Necrosis Factor Alpha ◽  
Content Type ◽  
Tnf Α ◽  
Factor Alpha ◽  
Necrosis Factor

ABSTRACTHaemophilus ducreyicauses chancroid, a genital ulcer disease. In human inoculation experiments, most volunteers fail to clear the bacteria despite the infiltration of innate and adaptive immune cells to the infected sites. The immunosuppressive protein indoleamine 2,3-dioxygenase (IDO) is a rate-limiting enzyme in thel-tryptophan-kynurenine metabolic pathway. Tryptophan depletion and tryptophan metabolites contribute to pathogen persistence by inhibiting T cell proliferation, inducing T cell apoptosis, and promoting the expansion of FOXP3+regulatory T (Treg) cells. We previously found that FOXP3+Treg cells are enriched in experimental lesions and thatH. ducreyiinduced IDO transcription in dendritic cells (DC) derived from blood of infected volunteers who developed pustules. Here, we showed that enzymatically active IDO was induced in DC byH. ducreyi. Neutralizing antibodies against interferon alpha/beta receptor 2 chain (IFNAR2) and tumor necrosis factor alpha (TNF-α) inhibited IDO induction. Inhibitors of the mitogen-activated protein kinase (MAPK) p38 and nuclear factor-κB (NF-κB) also inhibited IDO expression. Neither bacterial contact with nor uptake by DC was required for IDO activation.H. ducreyiculture supernatant andH. ducreyilipooligosaccharides (LOS) induced IDO expression, which required type I interferons, TNF-α, and the three MAPK (p38, c-Jun N-terminal kinase, and extracellular signal regulated kinase) and NF-κB pathways. In addition, LOS-induced IFN-β activated the JAK-STAT pathway. Blocking the LOS/Toll-like receptor 4 (TLR4) signaling pathway greatly reducedH. ducreyi-induced IDO production. These findings indicate thatH. ducreyi-induced IDO expression in DC is largely mediated by LOS via type I interferon- and TNF-α-dependent mechanisms and the MAPK, NF-κB, and JAK-STAT pathways.

scholarly journals Macrophage-Elicited Osteoclastogenesis in Response to Bacterial Stimulation Requires Toll-Like Receptor 2-Dependent Tumor Necrosis Factor-Alpha Production

2007 ◽  
Vol 76 (2) ◽  
pp. 812-819 ◽  
Author(s):  
Takashi Ukai ◽  
Hiromichi Yumoto ◽  
Frank C. Gibson ◽  
Caroline Attardo Genco
Keyword(s):  
Tumor Necrosis Factor ◽  
Cell Surface ◽  
Tumor Necrosis Factor Alpha ◽  
Tumor Necrosis ◽  
Toll Like Receptor ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Toll Like Receptor 2 ◽  
Factor Alpha ◽  
Necrosis Factor

ABSTRACT The receptor activator of NF-κB ligand (RANKL) and the proinflammatory cytokines are believed to play important roles in osteoclastogenesis. We recently reported that the innate immune recognition receptor, Toll-like receptor 2 (TLR2), is crucial for inflammatory bone loss in response to infection by Porphyromonas gingivalis, the primary organism associated with chronic inflammatory periodontal disease. However, the contribution of macrophage-expressed TLRs to osteoclastogenesis has not been defined. In this study, we defined a requirement for TLR2 in tumor necrosis factor-alpha (TNF-α)-elicited osteoclastogenesis in response to exposure to P. gingivalis. Culture supernatant (CS) fluids from P. gingivalis-stimulated macrophages induced bone marrow macrophage-derived osteoclastogenesis. This activity was dependent on TNF-α and occurred independently of RANKL, interleukin-1β (IL-1β), and IL-6. CS fluids from P. gingivalis-stimulated TLR2−/− macrophages failed to express TNF-α, and these fluids induced significantly less osteoclast formation compared with that of the wild-type or the TLR4−/− macrophages. In addition, P. gingivalis exposure induced up-regulation of TLR2 expression on the cell surface of macrophages, which was demonstrated to functionally react to reexposure to P. gingivalis, as measured by a further increase in TNF-α production. These results demonstrate that macrophage-dependent TLR2 signaling is crucial for TNF-α-dependent/RANKL-independent osteoclastogenesis in response to P. gingivalis infection. Furthermore, the ability of P. gingivalis to induce the cell surface expression of TLR2 may contribute to the chronic inflammatory state induced by this pathogen.

scholarly journals Human Macrophages, but Not Dendritic Cells, Are Activated and Produce Alpha/Beta Interferons in Response to Mopeia Virus Infection

2004 ◽  
Vol 78 (19) ◽  
pp. 10516-10524 ◽  
Author(s):  
Delphine Pannetier ◽  
Caroline Faure ◽  
Marie-Claude Georges-Courbot ◽  
Vincent Deubel ◽  
Sylvain Baize
Keyword(s):  
Dendritic Cells ◽  
Adaptive Immune Response ◽  
Hemorrhagic Fever ◽  
Surface Expression ◽  
Lassa Fever ◽  
Lassa Virus ◽  
Necrosis Factor Alpha ◽  
Factor Alpha ◽  
The Difference ◽  
Antigen Presenting

ABSTRACT Lassa virus (LV) and Mopeia virus (MV) are closely related members of the Arenavirus genus, sharing 75% amino acid sequence identity. However, LV causes hemorrhagic fever in humans and nonhuman primates, whereas MV cannot induce disease. We have previously shown that antigen-presenting cells (APC)—macrophages (MP) and dendritic cells (DC)—sustain high replication rates of LV but are not activated, suggesting that they play a role in the immunosuppression observed in severe cases of Lassa fever. Here, we infected human APC with MV and analyzed the cellular responses induced. MV infection was productive in MP and even more so in DC. Apoptosis was not induced in either cell type. Moreover, unlike DC, MP were early and strongly activated in response to MV, as shown by the increased surface expression of CD86, CD80, CD54, CD40, and HLA-abc and by the production of mRNA encoding alpha interferon (IFN-α), IFN-β, tumor necrosis factor alpha and interleukin-6. In addition, MV-infected MP produced less of the virus than DC, which was related to the fact that these cells secreted IFN-α. Thus, the strong activation of MP is probably a major event in the control of MV infection and may be involved in the induction of an adaptive immune response in infected hosts. These results may explain the difference in pathogenicity between LV and MV.

scholarly journals Glucocorticoids and Tumor Necrosis Factor Alpha Cooperatively Regulate Toll-Like Receptor 2 Gene Expression

2004 ◽  
Vol 24 (11) ◽  
pp. 4743-4756 ◽  
Author(s):  
Marcela A. Hermoso ◽  
Tetsuya Matsuguchi ◽  
Kathleen Smoak ◽  
John A. Cidlowski
Keyword(s):  
Innate Immunity ◽  
Transcription Factors ◽  
Tumor Necrosis Factor ◽  
Tumor Necrosis ◽  
Toll Like Receptor ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Toll Like Receptor 2 ◽  
Factor Alpha ◽  
Necrosis Factor

ABSTRACT Tumor necrosis factor alpha (TNF-α) and glucocorticoids are widely recognized as mutually antagonistic regulators of adaptive immunity and inflammation. Surprisingly, we show here that they cooperatively regulate components of innate immunity. The Toll-like receptor 2 (TLR2) gene encodes a transmembrane receptor critical for triggering innate immunity. Although TLR2 mRNA and protein are induced by inflammatory molecules such as TNF-α, we show that TLR2 is also induced by the anti-inflammatory glucocorticoids in cells where they also regulate MKP-1 mRNA and protein levels. TNF-α and glucocorticoids cooperate to regulate the TLR2 promoter, through the involvement of a 3′ NF-κB site, a STAT-binding element, and a 3′ glucocorticoid response element (GRE). Molecular studies show that the IκBα superrepressor or a STAT dominant negative element prevented TNF-α and dexamethasone stimulation of TLR2 promoter. Similarly, an AF-1 deletion mutant of glucocorticoid receptor or ablation of a putative GRE notably reduced the cooperative regulation of TLR2. Using chromatin immunoprecipitation assays, we demonstrate that all three transcription factors interact with both endogenous and transfected TLR2 promoters after stimulation by TNF-α and dexamethasone. Together, these studies define novel signaling mechanism for these three transcription factors, with a profound impact on discrimination of innate and adaptive immune responses.

scholarly journals The Staphylococcus aureus Lipoprotein SitC Colocalizes with Toll-Like Receptor 2 (TLR2) in Murine Keratinocytes and Elicits Intracellular TLR2 Accumulation

2010 ◽  
Vol 78 (10) ◽  
pp. 4243-4250 ◽  
Author(s):  
P. Müller ◽  
M. Müller-Anstett ◽  
J. Wagener ◽  
Q. Gao ◽  
S. Kaesler ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Host Cells ◽  
Hek293 Cells ◽  
Toll Like Receptor ◽  
Intracellular Accumulation ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Tlr2 Activation ◽  
Toll Like Receptor 2 ◽  
Factor Alpha

ABSTRACT SitC is one of the predominant lipoproteins in Staphylococcus aureus. Recently, SitC was shown to be capable of stimulating Toll-like receptor 2 (TLR2), but the mechanism of TLR2 activation by SitC has not been analyzed in detail so far. In this study, we purified C-terminally His-tagged SitC (SitC-His) from Staphylococcus aureus. SitC-His induced interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) release in human monocytes and also NF-κB activation in TLR2-transfected HEK293 cells, indicating TLR2-specific activation. SitC not only induced a TLR2-dependent release of IL-6 in primary murine keratinocytes (MKs) but also induced intracellular accumulation of TLR2, which was time and concentration dependent. Cy2-labeled SitC-His colocalized specifically with TLR2 in MKs and was also internalized in TLR2 knockout MKs, suggesting a TLR2-independent uptake. Neither activation nor colocalization of SitC-His was observed with TLR4 or Nod2. The results show that the native lipoprotein SitC-His specifically colocalizes with TLR2, is internalized by host cells, induces proinflammatory cytokines, and triggers intracellular accumulation of TLR2.

scholarly journals Effect of Mycobacterium bovis BCG Vaccinationon Mycobacterium-Specific Cellular Proliferation and TumorNecrosis Factor Alpha Production from Distinct Guinea PigLeukocytePopulations

2003 ◽  
Vol 71 (12) ◽  
pp. 7035-7042 ◽  
Author(s):  
Todd M. Lasco ◽  
Toshiko Yamamoto ◽  
Teizo Yoshimura ◽  
Shannon Sedberry Allen ◽  
Lynne Cassone ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Mycobacterium Bovis ◽  
Cellular Proliferation ◽  
Strong Positive Correlation ◽  
Necrosis Factor Alpha ◽  
Alpha Production ◽  
Tnf Α ◽  
Factor Alpha ◽  
Mycobacterial Strain ◽  
Necrosis Factor

ABSTRACT In this study, we focused on three leukocyte-rich guinea pig cell populations, bronchoalveolar lavage (BAL) cells, resident peritoneal cells (PC), and splenocytes (SPC). BAL cells, SPC, and PC were stimulated either with live attenuated Mycobacterium tuberculosis H37Ra or with live or heat-killed virulent M. tuberculosis H37Rv (multiplicity of infection of 1:100). Each cell population was determined to proliferate in response to heat-killed virulent H37Rv, whereas no measurable proliferative response could be detected upon stimulation with live mycobacteria. Additionally, this proliferative capacity (in SPC and PC populations) was significantly enhanced upon prior vaccination with Mycobacterium bovis BCG. Accordingly, in a parallel set of experiments we found a strong positive correlation between production of antigen-specific bioactive tumor necrosis factor alpha (TNF-α) and prior vaccination with BCG. A nonspecific stimulus, lipopolysaccharide, failed to induce this effect on BAL cells, SPC, and PC. These results showed that production of bioactive TNF-α from mycobacterium-stimulated guinea pig cell cultures positively correlates with the vaccination status of the host and with the virulence of the mycobacterial strain.

scholarly journals Human Mast Cell Activation by Staphylococcus aureus: Interleukin-8 and Tumor Necrosis Factor Alpha Release and the Role of Toll-Like Receptor 2 and CD48 Molecules

2008 ◽  
Vol 76 (10) ◽  
pp. 4489-4497 ◽  
Author(s):  
Claudio M. Rocha-de-Souza ◽  
Beata Berent-Maoz ◽  
David Mankuta ◽  
Allon E. Moses ◽  
Francesca Levi-Schaffer
Keyword(s):  
Staphylococcus Aureus ◽  
Mast Cells ◽  
Tumor Necrosis ◽  
Toll Like Receptor ◽  
Atopic Diseases ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Toll Like Receptor 2 ◽  
Factor Alpha ◽  
Necrosis Factor

ABSTRACT The ability of Staphylococcus aureus to invade and survive within host cells is believed to contribute to its propensity to cause persistent and metastatic infections. In addition, S. aureus infections often are associated with atopic diseases such as dermatitis, rhinitis, and asthma. Mast cells, the key cells of allergic diseases, have a pivotal role in innate immunity and have the capacity of phagocytosis, and they can destroy some pathogenic bacteria. However, little is known about the ability of some other bacteria to survive and overcome mast cell phagocytosis. Therefore, we were interested in evaluating the interplay between mast cells and S. aureus. In this study, we show that human cord blood-derived mast cells (CBMC) can be infected by pathogenic S. aureus. S. aureus displayed a high adherence to mast cells as well as invasive and survival abilities within them. However, when infections were performed in the presence of cytochalasin D or when CBMC were preincubated with anti-Toll-like receptor 2 (TLR2) or anti-CD48 antibodies, the invasiveness and the inflammatory response were abrogated, respectively. Furthermore, we observed an increase of TLR2 and CD48 molecules on CBMC after S. aureus infection. The infection of CBMC with S. aureus also caused the release of tumor necrosis factor alpha (TNF-α) and interleukin-8 (IL-8). Both live and killed S. aureus organisms were found to trigger TNF-α and IL-8 release by CBMC in a time-dependent manner. Cumulatively, these findings suggest that S. aureus internalizes and survives in mast cells. This may play an important role in infections and in atopic diseases associated with S. aureus.

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