[Show abstract][Hide abstract] ABSTRACT: IL-6 plays a central role in supporting pathological TH2 and TH17 cell development and inhibiting the protective T regulatory cells in allergic asthma. TH17 cells have been demonstrated to regulate allergic asthma in general and T-bet-deficiency-induced asthma in particular. Here we found an inverse correlation between T-bet and Il-6 mRNA expression in asthmatic children. Moreover, experimental subcutaneous immunotherapy (SIT) in T-bet((-/-)) mice inhibited IL-6, IL-21R and lung TH17 cells in a setting of asthma. Finally, local delivery of an anti-IL-6R antibody in T-bet((-/-)) mice resulted in the resolution of this allergic trait. Noteworthy, BATF, crucial for the immunoglobulin-class-switch and TH2,TH17 development, was found down-regulated in the lungs of T-bet((-/-)) mice after SIT and after treatment with anti-IL-6R antibody, indicating a critical role of IL-6 in controlling BATF/IRF4 integrated functions in TH2, TH17 cells and B cells also in a T-bet independent fashion in allergic asthma.
[Show abstract][Hide abstract] ABSTRACT: NFAT transcription factors control T-cell activation and function. Specifically, the transcription factor NFATc2 affects the regulation of cell differentiation and growth and plays a critical role in the development of colonic inflammation. Here, we used an experimental model of colitis-associated colorectal carcinoma to investigate the contribution of NFATc2 to the promotion of colonic tumors. Compared with wild-type animals that readily presented with multiple colon tumors, NFATc2-deficient mice were protected from tumor development. This observed decrease in colonic tumor progression was associated with reduced endoscopic inflammation, increased apoptosis of lamina propria T lymphocytes, and significantly reduced levels of the critical proinflammatory cytokines interleukin (IL)-21 and IL-6. Administration of hyper IL-6 abrogated protection from tumor progression in NFATc2-knockout mice and restored tumor incidence to control levels. Taken together, our findings highlight a pivotal role for NFATc2 in the establishment of inflammation-associated colorectal tumors mediated by control of IL-6 expression.
Cancer Research 06/2012; 72(17):4340-50. · 8.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: PURPOSE:
Although the central role of the immune system for tumor prognosis is generally accepted a single robust marker is not yet available.
Based on ROC (receiver operating characteristic) analyses robust markers were identified from a 60 gene B-cell derived metagene and analyzed in gene expression profiles of 1810 breast cancer, 1056 non-small cell lung cancer, 513 colorectal and 426 ovarian cancer patients. Protein and RNA levels were examined in paraffin embedded tissue of 330 breast cancer patients. The cell types were identified using immunohistochemical co-staining and confocal fluorescence microscopy.
We identified immunoglobulin kappa C (IGKC) which as a single marker is similarly predictive and prognostic as the entire B-cell metagene. IGKC was consistently associated with metastasis free survival across different molecular subtypes in node-negative breast cancer (n=965) and predicted response to anthracycline-based neoadjuvant chemotherapy (n=845) [P less than 0.001]. In addition, IGKC gene expression was prognostic in non-small cell lung cancer and colorectal cancer. No association was observed in ovarian cancer. IGKC protein expression was significantly associated with survival in paraffin embedded tissues of 330 breast cancer patients. Tumor infiltrating plasma cells were identified as the source of IGKC expression
Our findings provide IGKC as a novel diagnostic marker for risk stratification in human cancer and support concepts to exploit the humoral immune response for anti-cancer therapy. It could be validated in several independent cohorts and performed similarly well in RNA from fresh frozen as well as from paraffin tissue and on protein level by immunostaining.
Clinical Cancer Research 02/2012; · 7.84 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Humanized murine models comprise a new tool to analyze novel therapeutic strategies for allergic diseases of the intestine.
In this study we developed a human PBMC-engrafted murine model of allergen-driven gut inflammation and analyzed the underlying immunologic mechanisms.
Nonobese diabetic (NOD)-scid-γc(-/-) mice were injected intraperitoneally with human PBMCs from allergic donors together with the respective allergen or not. Three weeks later, mice were challenged with the allergen orally or rectally, and gut inflammation was monitored with a high-resolution video miniendoscopic system, as well as histologically.
Using the aeroallergens birch or grass pollen as model allergens and, for some donors, also hazelnut allergen, we show that allergen-specific human IgE in murine sera and allergen-specific proliferation and cytokine production of human CD4(+) T cells recovered from spleens after 3 weeks could only be measured in mice treated with PBMCs plus allergen. Importantly, these mice had the highest endoscopic scores evaluating translucent structure, granularity, fibrin, vascularity, and stool after oral or rectal allergen challenge and a strong histologic inflammation of the colon. Analyzing the underlying mechanisms, we demonstrate that allergen-associated colitis was dependent on IgE, human IgE receptor-expressing effector cells, and the mediators histamine and platelet-activating factor.
These results demonstrate that allergic gut inflammation can be induced in human PBMC-engrafted mice, allowing the investigation of pathophysiologic mechanisms of allergic diseases of the intestine and evaluation of therapeutic interventions.
The Journal of allergy and clinical immunology 01/2012; 129(4):1126-35. · 12.05 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: IL-28 (IFN-λ) cytokines exhibit potent antiviral and antitumor function but their full spectrum of activities remains largely unknown. Recently, IL-28 cytokine family members were found to be profoundly down-regulated in allergic asthma. We now reveal a novel role of IL-28 cytokines in inducing type 1 immunity and protection from allergic airway disease. Treatment of wild-type mice with recombinant or adenovirally expressed IL-28A ameliorated allergic airway disease, suppressed Th2 and Th17 responses and induced IFN-γ. Moreover, abrogation of endogenous IL-28 cytokine function in IL-28Rα(-/-) mice exacerbated allergic airway inflammation by augmenting Th2 and Th17 responses, and IgE levels. Central to IL-28A immunoregulatory activity was its capacity to modulate lung CD11c(+) dendritic cell (DC) function to down-regulate OX40L, up-regulate IL-12p70 and promote Th1 differentiation. Consistently, IL-28A-mediated protection was absent in IFN-γ(-/-) mice or after IL-12 neutralization and could be adoptively transferred by IL-28A-treated CD11c(+) cells. These data demonstrate a critical role of IL-28 cytokines in controlling T cell responses in vivo through the modulation of lung CD11c(+) DC function in experimental allergic asthma.
EMBO Molecular Medicine 06/2011; 3(6):348-61. · 7.80 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The transcription factor IRF4 is involved in several T-cell-dependent chronic inflammatory diseases. To elucidate the mechanisms for pathological cytokine production in colitis, we addressed the role of the IRF transcription factors in human inflammatory bowel disease (IBD) and experimental colitis.
IRF levels and cytokine production in IBD patients were studied as well as the effects of IRF4 deficiency in experimental colitis.
In contrast to IRF1, IRF5, and IRF8, IRF4 expression in IBD was augmented in the presence of active inflammation. Furthermore, IRF4 levels significantly correlated with IL-6 and IL-17 mRNA expression and to a lesser extent with IL-22 mRNA expression in IBD. To further explore the role of IRF4 under in vivo conditions, we studied IRF4-deficient and wildtype mice in experimental colitis. In contrast to DSS colitis, IRF4 deficiency was protective in T-cell-dependent transfer colitis associated with reduced RORα/γt levels and impaired IL-6, IL-17a, and IL-22 production, suggesting that IRF4 acts as a master regulator of mucosal Th17 cell differentiation. Subsequent mechanistic studies using database analysis, chromatin immunoprecipitation, and electrophoretic mobility shift assays identified a novel IRF4 binding site in the IL-17 gene promoter. Overexpression of IRF4 using retroviral infection induced IL-17 production and IL-17 together with IL-6 induced RORγt expression.
IRF4 can directly bind to the IL-17 promotor and induces mucosal RORγt levels and IL-17 gene expression thereby controlling Th17-dependent colitis. Targeting of this molecular mechanism may lead to novel therapeutic approaches in human IBD.
[Show abstract][Hide abstract] ABSTRACT: Signal transducer and activator of transcription (STAT)-3 inhibitors play an important role in regulating immune responses. Galiellalactone (GL) is a fungal secondary metabolite known to interfere with the binding of phosphorylated signal transducer and activator of transcription (pSTAT)-3 as well of pSTAT-6 dimers to their target DNA in vitro. Intra nasal delivery of 50 μg GL into the lung of naive Balb/c mice induced FoxP3 expression locally and IL-10 production and IL-12p40 in RNA expression in the airways in vivo. In a murine model of allergic asthma, GL significantly suppressed the cardinal features of asthma, such as airway hyperresponsiveness, eosinophilia and mucus production, after sensitization and subsequent challenge with ovalbumin (OVA). These changes resulted in induction of IL-12p70 and IL-10 production by lung CD11c(+) dendritic cells (DCs) accompanied by an increase of IL-3 receptor α chain and indoleamine-2,3-dioxygenase expression in these cells. Furthermore, GL inhibited IL-4 production in T-bet-deficient CD4(+) T cells and down-regulated the suppressor of cytokine signaling-3 (SOCS-3), also in the absence of STAT-3 in T cells, in the lung in a murine model of asthma. In addition, we found reduced amounts of pSTAT-5 in the lung of GL-treated mice that correlated with decreased release of IL-2 by lung OVA-specific CD4(+) T cells after treatment with GL in vitro also in the absence of T-bet. Thus, GL treatment in vivo and in vitro emerges as a novel therapeutic approach for allergic asthma by modulating lung DC phenotype and function resulting in a protective response via CD4(+)FoxP3(+) regulatory T cells locally.
International Immunology 01/2011; 23(1):1-15. · 3.14 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Lung cancer is the leading cause of cancer deaths worldwide. The cytokine interleukin-17A supports tumour vascularization and growth, however, its role in lung cancer is unknown. Here we show, in the lungs of patients with lung adenocarcinoma, an increase in interleukin-17A that is inversely correlated with the expression of T-bet and correlated with the T regulatory cell transcription factor Foxp3. Local targeting of interleukin-17A in experimental lung adenocarcinoma results in a reduction in tumour load, local expansion of interferon-γ-producing CD4(+) T cells and a reduction in lung CD4(+)CD25(+)Foxp3(+) regulatory T cells. T-bet((-/-)) mice have a significantly higher tumour load compared with wild-type mice. This is associated with the local upregulation of interleukin-23 and induction of interleukin-17A/interleukin-17R-expressing T cells infiltrating the tumour. Local anti-interleukin-17A antibody treatment partially improves the survival of T-bet((-/-)) mice. These results suggest that local anti-interleukin-17A antibody therapy could be considered for the treatment of lung tumours.
[Show abstract][Hide abstract] ABSTRACT: The pro-inflammatory cytokine interleukin (IL)-6 (refs. 1-5) can bind to cells lacking the IL-6 receptor (IL-6R) when it forms a complex with the soluble IL-6R (sIL-6R) (trans signaling). Here, we have assessed the contribution of this system to the increased resistance of mucosal T cells against apoptosis in Crohn disease (CD), a chronic inflammatory disease of the gastrointestinal tract. A neutralizing antibody against IL-6R suppressed established experimental colitis in various animal models of CD mediated by type 1 T-helper cells, by inducing apoptosis of lamina propria T cells. Similarly, specific neutralization of sIL-6R in vivo by a newly designed gp130-Fc fusion protein caused suppression of colitis activity and induction of apoptosis, indicating that sIL-6R prevents mucosal T-cell apoptosis. In patients with CD, mucosal T cells showed strong evidence for IL-6 trans signaling, with activation of signal transducer and activator of transcription 3, bcl-2 and bcl-xl. Blockade of IL-6 trans signaling caused T-cell apoptosis, indicating that the IL-6-sIL-6R system mediates the resistance of T cells to apoptosis in CD. These data indicate that a pathway of T-cell activation driven by IL-6-sIL-6R contributes to the perpetuation of chronic intestinal inflammation. Specific targeting of this pathway may be a promising new approach for the treatment of CD.
Nature medicine 11/2010; 16(11):1341. · 27.14 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The proinflammatory cytokines interleukin 1beta (IL-1beta) and IL-18 are central players in the pathogenesis of inflammatory bowel disease (IBD). In response to a variety of microbial components and crystalline substances, both cytokines are processed via the caspase-1-activating multiprotein complex, the NLRP3 inflammasome. Here, the role of the NLRP3 inflammasome in experimental colitis induced by dextran sodium sulfate (DSS) was examined.
IL-1beta production in response to DSS was studied in macrophages of wild-type, caspase-1(-/-), NLRP3(-/-), ASC(-/-), cathepsin B(-/-) or cathepsin L(-/-) mice. Colitis was induced in C57BL/6 and NLRP3(-/-) mice by oral DSS administration. A clinical disease activity score was evaluated daily. Histological colitis severity and expression of cytokines were determined in colonic tissue.
Macrophages incubated with DSS in vitro secreted high levels of IL-1beta in a caspase-1-dependent manner. IL-1beta secretion was abrogated in macrophages lacking NLRP3, ASC or caspase-1, indicating that DSS activates caspase-1 via the NLRP3 inflammasome. Moreover, IL-1beta secretion was dependent on phagocytosis, lysosomal maturation, cathepsin B and L, and reactive oxygen species (ROS). After oral administration of DSS, NLRP3(-/-) mice developed a less severe colitis than wild-type mice and produced lower levels of proinflammatory cytokines in colonic tissue. Pharmacological inhibition of caspase-1 with pralnacasan achieved a level of mucosal protection comparable with NLRP3 deficiency.
The NLRP3 inflammasome was identified as a critical mechanism of intestinal inflammation in the DSS colitis model. The NLRP3 inflammasome may serve as a potential target for the development of novel therapeutics for patients with IBD.
[Show abstract][Hide abstract] ABSTRACT: The Ca(2+)-regulated calcineurin/nuclear factor of activated T cells (NFAT) cascade controls alternative pathways of T-cell activation and peripheral tolerance. Here, we describe reduction of NFATc2 mRNA expression in the lungs of patients with bronchial adenocarcinoma. In a murine model of bronchoalveolar adenocarcinoma, mice lacking NFATc2 developed more and larger solid tumors than wild-type littermates. The extent of central tumor necrosis was decreased in the tumors in NFATc2((-/-)) mice, and this finding was associated with reduced tumor necrosis factor-alpha and interleukin-2 (IL-2) production by CD8(+) T cells. Adoptive transfer of CD8(+) T cells of NFATc2((-/-)) mice induced transforming growth factor-beta(1) in the airways of recipient mice, thus supporting CD4(+)CD25(+)Foxp-3(+)glucocorticoid-induced tumor necrosis factor receptor (GITR)(+) regulatory T (T(reg)) cell survival. Finally, engagement of GITR in NFATc2((-/-)) mice induced IFN-gamma levels in the airways, reversed the suppression by T(reg) cells, and costimulated effector CD4(+)CD25(+) (IL-2Ralpha) and memory CD4(+)CD127(+) (IL-7Ralpha) T cells, resulting in abrogation of carcinoma progression. Agonistic signaling through GITR, in the absence of NFATc2, thus emerges as a novel possible strategy for the treatment of human bronchial adenocarcinoma in the absence of NFATc2 by enhancing IL-2Ralpha(+) effector and IL-7Ralpha(+) memory-expressing T cells.
Cancer Research 05/2009; 69(7):3069-76. · 8.65 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: EBV-induced gene 3 (EBI-3) codes for a soluble type I receptor homologous to the p40 subunit of IL-12 that is expressed by APCs following activation. In this study, we assessed the role of EBI-3 in a model of lung melanoma metastasis. Intravenous injection of the B16-F10 cell line resulted in a significant reduction of lung tumor metastasis in EBI-3(-/-) recipient mice compared with wild-type mice. The immunological finding accompanying this effect was the expansion of a newly described cell subset called IFN-gamma producing killer dendritic cells associated with CD8(+) T cell responses in the lung of EBI-3(-/-) mice including IFN-gamma release and TNF-alpha-induced programmed tumor cell death. Depletion of CD8(+) T cells as well as targeting T-bet abrogated the protective effects of EBI-3 deficiency on lung melanoma metastases. Finally, adoptive transfer of EBI-3(-/-) CD8(+) T cells into tumor bearing wild-type mice inhibited lung metastasis in recipient mice. Taken together, these data demonstrate that targeting EBI-3 leads to a T-bet-mediated antitumor CD8(+) T cell responses in the lung.
The Journal of Immunology 12/2008; 181(9):6148-57. · 5.52 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: IL-2 influences both survival and differentiation of CD4(+) T effector and regulatory T cells. We studied the effect of i.n. administration of Abs against the alpha- and the beta-chains of the IL-2R in a murine model of allergic asthma. Blockade of the beta- but not the alpha-chain of the IL-2R after allergen challenge led to a significant reduction of airway hyperresponsiveness. Although both treatments led to reduction of lung inflammation, IL-2 signaling, STAT-5 phosphorylation, and Th2-type cytokine production (IL-4 and IL-5) by lung T cells, IL-13 production and CD4(+) T cell survival were solely inhibited by the blockade of the IL-2R beta-chain. Moreover, local blockade of the common IL-2R/IL-15R beta-chain reduced NK cell number and IL-2 production by lung CD4(+)CD25(+) and CD4(+)CD25(-) T cells while inducing IL-10- and TGF-beta-producing CD4(+) T cells in the lung. This cytokine milieu was associated with reduced CD4(+) T cell proliferation in the draining lymph nodes. Thus, local blockade of the beta-chain of the IL-2R restored an immunosuppressive cytokine milieu in the lung that ameliorated both inflammation and airway hyperresponsiveness in experimental allergic asthma. These findings provide novel insights into the functional role of IL-2 signaling in experimental asthma and suggest that blockade of the IL-2R beta-chain might be useful for therapy of allergic asthma in humans.
The Journal of Immunology 08/2008; 181(3):1917-26. · 5.52 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The proinflammatory cytokine IL-6 seems to have an important role in the intestinal inflammation that characterizes inflammatory bowel diseases (IBDs) such as Crohn disease and ulcerative colitis. However, little is known about the molecular mechanisms regulating IL-6 production in IBD. Here, we assessed the role of the transcriptional regulator IFN regulatory factor-4 (IRF4) in this process. Patients with either Crohn disease or ulcerative colitis exhibited increased IRF4 expression in lamina propria CD3+ T cells as compared with control patients. Consistent with IRF4 having a regulatory function in T cells, in a mouse model of IBD whereby colitis is induced in RAG-deficient mice by transplantation with CD4+CD45RB(hi) T cells, adoptive transfer of wild-type but not IRF4-deficient T cells resulted in severe colitis. Furthermore, IRF4-deficient mice were protected from T cell-dependent chronic intestinal inflammation in trinitrobenzene sulfonic acid- and oxazolone-induced colitis. In addition, IRF4-deficient mice with induced colitis had reduced mucosal IL-6 production, and IRF4 was required for IL-6 production by mucosal CD90+ T cells, which it protected from apoptosis. Finally, the protective effect of IRF4 deficiency could be abrogated by systemic administration of either recombinant IL-6 or a combination of soluble IL-6 receptor (sIL-6R) plus IL-6 (hyper-IL-6). Taken together, our data identify IRF4 as a key regulator of mucosal IL-6 production in T cell-dependent experimental colitis and suggest that IRF4 might provide a therapeutic target for IBDs.
Journal of Clinical Investigation 08/2008; 118(7):2415-26. · 12.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Inhibition of histone deacetylases, well known for its antiproliferative efficacy in vivo, was recently shown to ameliorate inflammation in experimental colitis. Since inflammatory bowel disease is associated with an increased risk of developing colon cancer, here the combined anti-inflammatory and proapoptotic efficacy of histone deacetylase inhibitors was studied in mouse models.
The novel histone deacetylase inhibitor ITF2357 was compared with suberoylanilide hydroxamic acid in models of experimental colitis. Effects on tumour growth were studied after treatment of mice with azoxymethane and dextran sulphate sodium, and in interleukin 10 (IL10) knockout mice, respectively. Possible underlying mechanisms involving apoptosis and nuclear factor (NF)-kappaB activation were addressed by flow cytometry and western blot.
In dextran sulphate sodium- and trinitrobenzene sulphonic acid-induced colitis, treatment with ITF2357 was superior to suberoylanilide hydroxamic acid as shown by macroscopic and histological amelioration of inflammation, by reduced production of interferon gamma (IFN gamma) and by increased production of IL10. In both models of inflammation-mediated tumourigenesis, inhibition of histone deacetylases resulted in a significant suppression of tumour growth in terms of size and number, along with reduced signs of inflammation. As for potential mechanisms of ITF2357 action, increased acetylation of histone 3, reduced production of IFN gamma and enhanced apoptosis in lamina propria mononuclear cells were found to accompany a histone deacetylase-dependent activation of NF-kappaB.
These results indicate that inhibition of histone deactylases can attenuate inflammation-mediated tumour growth, which is paralled by an inhibition of NF-kappaB. Thus histone deacetylase inhibitors provide a promising strategy that combines anti-inflammatory and proapoptotic modes of action.
[Show abstract][Hide abstract] ABSTRACT: The transcriptional regulation of cytokines released and controlled by memory T cells is not well understood. Defective IFN-gamma production in allergic asthma correlates in human beings with the risk of wheezing in childhood.
To understand the role of the transcription factor nuclear factor of activated T cells 2 (NFATc2) in memory and effector T cells in the airways in experimental allergic asthma.
We used murine models of allergic asthma and adoptive cell transfer of fluorescence-activated sorted cells in a disease model.
Mice lacking NFATc2 developed an increase in airwayhyperresponsiveness (AHR), remodeling, and serum IgE levelson ovalbumin sensitization. This phenotype was associated withCD81CD1222 T cells deficient in IFN-g production in theairways. The origin of this phenotype in NFATc2(2/2) mice wasrelated to an expanded population of lung CD81CD1221(IL-2Rb chain) CD127hi (IL-7 receptor [R] a chain1) long-livedmemory cells. Adoptive transfer of ovalbumin-specific CD81NFATc2(2/2) T cells enhanced the AHR generated byNFATc2(2/2) CD41 T cells in immunodeficient mice, increasedIL-17, and reduced IFN-g production in the reconstituted mice. Depletion of the memory CD81CD1221IL-7Rhigh T-cellpopulation corrected the defect in IFN-g production by lungNFATc2(2/2) CD81CD1222 cells and abrogated the increasedAHR observed in NFATc2(2/2) CD81 T-cell-reconstituted micewith a severe combined immunodeficiency disorder.
Taken together, our results suggest that NFATc2 expression in long-lived memory CD8+ T cells controls IL-2 and IFN-gamma production in lung CD8+ T cells, which then limits TH17 and TH2 development in the airways during allergen challenge.
The Journal of allergy and clinical immunology 05/2008; 121(4):992-9.e6. · 12.05 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Members of the transforming growth factor beta (TGF-beta) superfamily of signaling molecules are involved in the regulation of many developmental processes that involve the interaction between mesenchymal and epithelial tissues. Smad7 is a potent inhibitor of many members of the TGF-beta family, notably TGF-beta and activin. In this study, we show that embryonic overexpression of Smad7 in stratified epithelia using a keratin 5 promoter, results in severe morphogenetic defects in skin and teeth and leads to embryonic and perinatal lethality. To further analyze the functions of Smad7 in epithelial tissues of adult mice, we used an expression system that allowed a controlled overexpression of Smad7 in terms of both space and time. Skin defects in adult mice overexpressing Smad7 were characterized by hyper-proliferation and missing expression of early markers of keratinocyte differentiation. Upon Smad7-mediated blockade of TGF-beta superfamily signaling, ameloblasts failed to produce an enamel layer in incisor teeth. In addition, TGF-beta blockade in adult mice altered the pattern of thymic T cell differentiation and the number of thymic T cells was significantly reduced. This study shows that TGF-beta superfamily signaling is essential for development of hair, tooth and T-cells as well as differentiation and proliferation control in adult tissues.
European Journal of Cell Biology 01/2008; 86(11-12):781-99. · 3.21 Impact Factor