Tumor immunoevasion via acidosis-dependent induction of regulatory tumor-associated macrophages.

Many tumors evolve sophisticated strategies to evade the immune system, and these represent major obstacles for efficient antitumor immune responses. Here we explored a molecular mechanism of metabolic communication deployed by highly glycolytic tumors for immunoevasion. In contrast to colon adenocarcinomas, melanomas showed comparatively high glycolytic activity, which resulted in high acidification of the tumor microenvironment. This tumor acidosis induced Gprotein-coupled receptor-dependent expression of the transcriptional repressor ICER in tumor-associated macrophages that led to their functional polarization toward a non-inflammatory phenotype and promoted tumor growth. Collectively, our findings identify a molecular mechanism of metabolic communication between non-lymphoid tissue and the immune system that was exploited by high-glycolytic-rate tumors for evasion of the immune system.

TH9 cells that express the transcription factor PU.1 drive T cell-mediated colitis via IL-9 receptor signaling in intestinal epithelial cells.

The molecular checkpoints that drive inflammatory bowel diseases are incompletely understood. Here we found more T cells expressing the transcription factor PU.1 and interleukin 9 (IL-9) in patients with ulcerative colitis. In an animal model, citrine reporter mice had more IL-9-expressing mucosal T cells in experimental oxazolone-induced colitis. IL-9 deficiency suppressed acute and chronic colitis. Mice with PU.1 deficiency in T cells were protected from colitis, whereas treatment with antibody to IL-9 suppressed colitis. Functionally, IL-9 impaired intestinal barrier function and prevented mucosal wound healing in vivo. Thus, our findings suggest that the TH9 subset of helper T cells serves an important role in driving ulcerative colitis by regulating intestinal epithelial cells and that TH9 cells represent a likely target for the treatment of chronic intestinal inflammation.

Alternative Splice Forms of CYLD Mediate Ubiquitination of SMAD7 to Prevent TGFB Signaling and Promote Colitis.

BACKGROUND & AIMS: The CYLD lysine 63 deubiquitinase gene (CYLD) encodes tumor suppressor protein that is mutated in familial cylindromatosus, and variants have been associated with Crohn disease (CD). Splice forms of CYLD that lack exons 7 and 8 regulate transcription factors and functions of immune cells. We examined the expression of splice forms of CYLD in colon tissues from patients with CD and their effects in mice. METHODS: We performed immunohistochemical analyses of colon tissues from patients with untreated CD and patients without inflammatory bowel diseases (controls). We obtained mice that expressed splice forms of CYLD (sCYLD mice) without or with SMAD7 (sCYLD/SMAD7 mice) from transgenes and CYLD-knockout mice (with or without transgenic expression of SMAD7) and performed endoscopic analyses. Colitis was induced in Rag1-/- mice by transfer of CD4+ CD62L+ T cells from C57/Bl6 or transgenic mice. T cells were isolated from mice and analyzed by flow cytometry and quantitative real-time polymerase chain reaction and intestinal tissues were analyzed by histology and immunohistochemistry. CYLD forms were expressed in mouse embryonic fibroblasts, primary T cells, and HEK293T cells, which were analyzed by immunoblot, mobility shift, and immunoprecipitation assays. RESULTS: The colonic lamina propria from patients with CD was infiltrated by T cells and had higher levels of sCYLD (but not full-length CYLD) and SMAD7 than tissues from controls. Incubation of mouse embryonic fibroblasts and T cells with transforming growth factor ß increased their production of sCYLD and decreased full-length CYLD. Transgenic expression of sCYLD and SMAD7 in T cells prevented the differentiation of regulatory T cells and T-helper type 17 cells and increased the differentiation of T-helper type 1 cells. The same effects were observed in colon tissues from sCYLD/SMAD7 mice but not in those from CYLD-knockout SMAD7 mice. The sCYLD mice had significant increases in the numbers of T-helper type 1 cells and CD44high CD62Llow memory-effector CD4+ T cells in the spleen and mesenteric lymph nodes compared with wild-type mice; sCYLD/SMAD7 mice had even larger increases. The sCYLD/SMAD7 mice spontaneously developed severe colitis, with infiltration of the colon by dendritic cells, neutrophils, macrophages, and CD4+ T cells and increased levels of Ifng, Il6, Il12a, Il23a, and Tnf mRNAs. Co-transfer of regulatory T cells from wild-type, but not from sCYLD/SMAD7, mice prevented the induction of colitis in Rag1-/- mice by CD4+ T cells. We found increased levels of poly-ubiquitinated SMAD7 in sCYLD CD4+ T cells. CYLD formed a nuclear complex with SMAD3, whereas sCYLD recruited SMAD7 to the nucleus, which inhibited the expression of genes regulated by SMAD3 and SMAD4. We found that sCYLD mediated lysine 63-linked ubiquitination of SMAD7. The sCYLD-SMAD7 complex inhibited transforming growth factor ß signaling in CD4+ T cells. CONCLUSIONS: Levels of the spliced form of CYLD are increased in colon tissues from patients with CD. sCYLD mediates ubiquitination and nuclear translocation of SMAD7 and thereby decreases transforming growth factor ß signaling in T cells. This prevents immune regulatory mechanisms and leads to colitis in mice.

Rectal Delivery of a DNAzyme That Specifically Blocks the Transcription Factor GATA3 and Reduces Colitis in Mice.

BACKGROUND & AIMS: GATA3 is a transcription factor that regulates T-cell production of cytokines. We investigated the role of GATA3 in development of colitis in mice. METHODS: We performed quantitative polymerase chain reaction and immunofluorescence analyses of colon tissues from patients with Crohn's disease (n = 61) or ulcerative colitis (UC, n = 74) or from patients without inflammatory bowel diseases (n = 22), to measure levels of GATA3. Colitis was induced by administration of oxazolone or 2,4,6-trinitrobenzenesulfonic acid to control mice, mice with T-cell-specific deletion of GATA3, and mice with deletion of tumor necrosis factor receptor (TNFR) 1 and TNFR2 (TNFR double knockouts); some mice were given a GATA3-specific DNAzyme (hgd40) or a control DNAzyme via intrarectal administration, or systemic injections of an antibody to TNF before or during sensitization and challenge phase of colitis induction. Colon tissues were collected and immunofluorescence and histochemical analyses were performed. Lamina propria mononuclear cells and T cells were isolated and analyzed by flow cytometry or cytokine assays. Colonic distribution of labeled DNAzyme and inflammation were monitored by in vivo imaging (endoscopy) of mice. RESULTS: Levels of GATA3 messenger RNA were higher in colon tissues from patients with UC, but not ileal Crohn's disease, than control tissues; levels of GATA3 correlated with levels of inflammatory cytokines (interleukin [IL] 9, IL17A, IL6, IL5, IL4, IL13, and TNF). We observed increased expression of GATA3 by lamina propria T cells from mice with colitis compared with controls. Mice with T-cell-specific deletion of GATA3 did not develop colitis and their colonic tissues did not produce inflammatory cytokines (IL6, IL9, or IL13). The DNAzyme hgd40 inhibited expression of GATA3 messenger RNA by unstimulated and stimulated T cells, and distributed throughout the inflamed colons of mice with colitis. Colon tissues from mice given hgd40 had reduced expression of GATA3 messenger RNA, compared with mice given a control DNAzyme. Mice given hgd40 did not develop colitis after administration of oxazolone or 2,4,6-trinitrobenzenesulfonic acid; lamina propria cells from these mice expressed lower levels of IL6, IL9, and IL13 than cells from mice given the control DNAzyme. Mini-endoscopic images revealed that hgd40 and anti-TNF reduced colon inflammation over 3 days; hgd40 reduced colitis in TNFR double-knockout mice. CONCLUSIONS: Levels of GATA3 are increased in patients with UC and correlate with production of inflammatory cytokines in mice and humans. A DNAzyme that prevents expression of GATA3 reduces colitis in mice, independently of TNF, and reduces levels of cytokines in the colon. This DNAzyme might be developed for treatment of patients with UC.

Nuclear factor of activated T cells - a transcription factor family as critical regulator in lung and colon cancer.

Nuclear factor of activated T cells (NFAT) was first identified as a transcription factor which is activated upon T cell stimulation. Subsequent studies uncovered that a whole family of individual NFAT proteins exists with pleiotropic functions not only in immune but also in nonimmune cells. However, dysregulation of NFAT thereby favors malignant growth and cancer. Summarizing the recent advances in understanding how individual NFAT factors regulate the immune system, this review gives new insights into the critical role of NFAT in cancer development with special focus on inflammation-associated colorectal cancer.

Improvement of Spinocerebellar Ataxia 3 Symptoms Treated with Eurythmy Therapy: A Case Vignette.

A 58-year-old male with genetically confirmed spinocerebellar ataxia 3 was treated with 10 sessions of eurythmy therapy. He was rated 9 on the "Scale for Assessment and Rating of Ataxia" before therapy started. Among movement and mental symptoms, he complained about sleep disturbances, insensitivity in the feet, and spasms in the legs. The patient was asked to build strong inner images as a basis for the eurythmy therapy movement exercises. After 10 sessions, he reported improvement in sleep disturbances, insensitivity in the feet, and spasms in the legs. He improved to 7.5 points on the "Scale for Assessment and Rating of Ataxia". In the 3 months, before starting and during eurythmy therapy, the patient did not alter the only medication taken (Bryophyllum 50% powder) and did not undergo any other therapy.Ein 58-jähriger Mann mit genetisch bestätigter spinozerebellärer Ataxie 3 wurde mit 10 Sitzungen Heileurythmie behandelt. Vor Beginn der Therapie wurde er auf der "Scale for Assessment and Rating of Ataxia" mit 9 bewertet. Neben Bewegungs- und psychischen Symptomen klagte er über Schlafstörungen, Unempfindlichkeit in den Füßen und Spasmen in den Beinen. Der Patient wurde aufgefordert, starke innere Bilder als Grundlage für die heileurythmischen Bewegungsübungen aufzubauen. Nach 10 Sitzungen berichtete er über eine Verbesserung der Schlafstörungen, der Unempfindlichkeit in den Füßen und der Spasmen in den Beinen. Er verbesserte sich auf 7.5 Punkte auf der "Scale for Assessment and Rating of Ataxia". Während der drei Monate vor Beginn und während der Eurythmie Therapie änderte der Patient seine Medikation nicht (Bryophyllum 50% Pulver) und unterzog sich keiner weiteren Therapie.

PU.1-driven Th9 Cells Promote Colorectal Cancer in Experimental Colitis Models Through Il-6 Effects in Intestinal Epithelial Cells.

BACKGROUND AND AIMS: Colorectal cancer [CRC] is one of the most frequent malignancies, but the molecular mechanisms driving cancer growth are incompletely understood. We characterised the roles of the cytokine IL-9 and Th9 cells in regulating CRC development. METHODS: CRC patient samples and samples from AOM/DSS treated mice were analysed for expression of IL-9, CD3, and PU.1 by FACS analysis and immunohistochemistry. IL-9 citrine reporter mice, IL-9 knockout mice, and PU.1 and GATA3 CD4-Cre conditional knockout mice were studied in the AOM/DSS model. DNA minicircles or hyper-IL-6 were used for overexpression of cytokines in vivo. Effects of IL-6 and IL-9 were determined in organoid and T cell cultures. Claudin2/3 expression was studied by western blotting and bacterial translocation by FISH. RESULTS: We uncovered a significant expansion of IL-9- and PU.1-expressing mucosal Th9 cells in CRC patients, with particularly high levels in patients with colitis-associated neoplasias. PU.1+ Th9 cells accumulated in experimental colorectal neoplasias. Deficiency of IL-9 or inactivation of PU.1 in T cells led to impaired tumour growth in vivo, suggesting a protumoral role of Th9 cells. In contrast, GATA3 inactivation did not affect Th9-mediated tumour growth. Mechanistically, IL-9 controls claudin2/3 expression and T cell-derived IL-6 production in colorectal tumours. IL-6 abrogated the anti-proliferative effects of IL-9 in epithelial organoids in vivo. IL-9-producing Th9 cells expand in CRC and control IL-6 production by T cells. CONCLUSIONS: IL-9 is a crucial regulator of tumour growth in colitis-associated neoplasias and emerges as potential target for therapy.

The JAK1/3 inhibitor tofacitinib suppresses T cell homing and activation in chronic intestinal inflammation.

BACKGROUND & AIMS: The molecular mechanism of action of the Janus kinase (JAK) inhibitor tofacitinib is poorly understood. METHODS: Here, we analysed the inhibitory effect of tofacitinib on mucosal and blood T cells from patients with ulcerative colitis (UC). Furthermore tofacitinib treatment was analysed in experimental colitis models and wound healing. Additionally, tofacitinib effects were analysed in bioassays. RESULTS: Tofacitinib significantly reduced T cell derived inflammatory cytokine production (Th2, Th9, Th17) in patients with active UC. Additionally, impaired expression of the homing receptors alpha4/beta1 and alpha4/beta7 as well as reduced gut homing capacity of T cells in a humanized mouse model of colitis were observed. Tofacitinib suppressed acute and chronic oxazolone colitis compared to untreated wild-type mice associated with downregulation of cytokines produced by Th2, Th9 and Th17 cells. Functionally, tofacitinib induced apoptosis of intestinal epithelial cells and prevented mucosal wound healing in vivo at higher concentration. Thus, our findings suggest that tofacitinib is quite effective in protecting from colitis by inhibition of a bundle of T cell derived cytokines like IL-5, IL-6, IL-9, IL-13 and IL-17A. CONCLUSION: Application of tofacitinib emerges as an attractive concept for treatment of chronic intestinal inflammation at lower concentrations, whereas higher concentrations require attention due to prolonged wound healing.

Development of a documentation instrument for movement-orientated Mind-Body-Therapies taking the example of Eurythmy-Therapy.

INTRODUCTION: Movement orientated Mind-Body-Interventions become more popular. But there are no standardized documentation tools to show if an improvement in movement could correlate with an improvement in health. Yet systematic documentation is a vital requirement to their efficacy. METHOD: We developed a 5-module documentation structure including patients' perspective. Over a period of five months 11 therapists used the modules to document their treatments on 41 patients and evaluated their feasibility at hand a questionnaire. RESULTS: 10 therapists and 37 patients met the inclusion criteria. In a documented variety of treatment concepts moderate to large effect size in observed movement qualities was found. Furthermore large correlation of observed movement qualities and patients' self-reported Quality of Life indicators could be shown. CONCLUSION: The modules were regarded feasible. Moreover, the outcomes showed initial sensitivity to change. They should therefore be tested in various movement orientated Mind-Body-Therapies.

FUSE binding protein 1 (FUBP1) expression is upregulated by T-cell acute lymphocytic leukemia protein 1 (TAL1) and required for efficient erythroid differentiation.

During erythropoiesis, haematopoietic stem cells (HSCs) differentiate in successive steps of commitment and specification to mature erythrocytes. This differentiation process is controlled by transcription factors that establish stage- and cell type-specific gene expression. In this study, we demonstrate that FUSE binding protein 1 (FUBP1), a transcriptional regulator important for HSC self-renewal and survival, is regulated by T-cell acute lymphocytic leukaemia 1 (TAL1) in erythroid progenitor cells. TAL1 directly activates the FUBP1 promoter, leading to increased FUBP1 expression during erythroid differentiation. The binding of TAL1 to the FUBP1 promoter is highly dependent on an intact GATA sequence in a combined E-box/GATA motif. We found that FUBP1 expression is required for efficient erythropoiesis, as FUBP1-deficient progenitor cells were limited in their potential of erythroid differentiation. Thus, the finding of an interconnection between GATA1/TAL1 and FUBP1 reveals a molecular mechanism that is part of the switch from progenitor- to erythrocyte-specific gene expression. In summary, we identified a TAL1/FUBP1 transcriptional relationship, whose physiological function in haematopoiesis is connected to proper erythropoiesis.

miRNA142-3p targets Tet2 and impairs Treg differentiation and stability in models of type 1 diabetes.

In type 1 diabetes, the appearance of islet autoantibodies indicates the onset of islet autoimmunity, often many years before clinical symptoms arise. While T cells play a major role in the destruction of pancreatic beta cells, molecular underpinnings promoting aberrant T cell activation remain poorly understood. Here, we show that during islet autoimmunity an miR142-3p/Tet2/Foxp3 axis interferes with the efficient induction of regulatory T (Treg) cells, resulting in impaired Treg stability in mouse and human. Specifically, we demonstrate that miR142-3p is induced in islet autoimmunity and that its inhibition enhances Treg induction and stability, leading to reduced islet autoimmunity in non-obese diabetic mice. Using various cellular and molecular approaches we identify Tet2 as a direct target of miR142-3p, thereby linking high miR142-3p levels to epigenetic remodeling in Tregs. These findings offer a mechanistic model where during islet autoimmunity miR142-3p/Tet2-mediated Treg instability contributes to autoimmune activation and progression.

The transcriptional regulator FUBP1 influences disease outcome in murine and human myeloid leukemia.

The transcriptional regulator far upstream element binding protein 1 (FUBP1) acts as an oncoprotein in solid tumor entities and plays a role in the maintenance of hematopoietic stem cells. However, its potential function in leukemia is unknown. In murine models of chronic (CML) and acute myeloid leukemia (AML) induced by BCR-ABL1 and MLL-AF9, respectively, knockdown of Fubp1 resulted in prolonged survival, decreased numbers of CML progenitor cells, decreased cell cycle activity and increased apoptosis. Knockdown of FUBP1 in CML and AML cell lines recapitulated these findings and revealed enhanced DNA damage compared to leukemia cells expressing wild type FUBP1 levels. FUBP1 was more highly expressed in human CML compared to normal bone marrow cells and its expression correlated with disease progression. In AML, higher FUBP1 expression in patient leukemia cells was observed with a trend toward correlation with shorter overall survival. Treatment of mice with AML with irinotecan, known to inhibit topoisomerase I and FUBP1, significantly prolonged survival alone or in combination with cytarabine. In summary, our data suggest that FUBP1 acts as cell cycle regulator and apoptosis inhibitor in leukemia. We demonstrated that FUBP1 might play a role in DNA repair, and its inhibition may improve outcome in leukemia patients.

A miRNA181a/NFAT5 axis links impaired T cell tolerance induction with autoimmune type 1 diabetes.

Molecular checkpoints that trigger the onset of islet autoimmunity or progression to human type 1 diabetes (T1D) are incompletely understood. Using T cells from children at an early stage of islet autoimmunity without clinical T1D, we find that a microRNA181a (miRNA181a)-mediated increase in signal strength of stimulation and costimulation links nuclear factor of activated T cells 5 (NFAT5) with impaired tolerance induction and autoimmune activation. We show that enhancing miRNA181a activity increases NFAT5 expression while inhibiting FOXP3+ regulatory T cell (Treg) induction in vitro. Accordingly, Treg induction is improved using T cells from NFAT5 knockout (NFAT5ko) animals, whereas altering miRNA181a activity does not affect Treg induction in NFAT5ko T cells. Moreover, high costimulatory signals result in phosphoinositide 3-kinase (PI3K)-mediated NFAT5, which interferes with FoxP3+ Treg induction. Blocking miRNA181a or NFAT5 increases Treg induction in murine and humanized models and reduces murine islet autoimmunity in vivo. These findings suggest targeting miRNA181a and/or NFAT5 signaling for the development of innovative personalized medicines to limit islet autoimmunity.

The role of morbidity for proxy-reported well-being in the last year of life.

Late-life well-being often shows steep deteriorations, but the contributing factors are not well understood, in part because data about people's final year of life are scarce. Here, we draw from and test theoretical perspectives that health-related vulnerabilities undermine the experience and skills older adults typically use to maintain well-being (Charles, 2010). To do so, we examined how various morbidity factors shape final-year well-being trajectories. We applied change score models to retrospective proxy-reports from the Socio-Economic Panel (N = 1,776; age at death = 19-101 years; 47% women) and covary for characteristics of the deceased and the bereaved proxy. Terminal decline in proxy-reported well-being amounted to 0.57 SD in less than a year, with larger individual differences at 3 months versus 12 months before death. Declines were reportedly steeper for those in poor health, need of care, not dying from sudden causes of death, dying with cancer, and not dying at home. People who entered their final year with preserved well-being and cognition experienced steeper final-year decrements. Morbidity factors conjointly accounted for less than 20% of variance, indicating that health decrements shape final-year well-being in multifaceted ways, but are not the be-all and the end-all of why well-being declines for some, but not for others. Unique effects of particular morbidity factors were modest, suggesting that prevailing multimorbidity makes the particular conditions in part interchangeable. Extending self-report data typically available until 1 year before death, our findings suggest that proxy-based results move our understanding of terminal well-being decline further. (PsycINFO Database Record

Chemically induced mouse models of acute and chronic intestinal inflammation.

Inflammatory bowel diseases (IBDs) result in diarrhea and abdominal pain with further potential complications such as tissue fibrosis and stenosis. Animal models help in understanding the immunopathogenesis of IBDs and in the design of novel therapeutic concepts. Here we present an updated version of a protocol we published in 2007 for key models of acute and chronic forms of colitis induced by 2,4,6-trinitro-benzene sulfonic acid (TNBS), oxazolone and dextran sulfate sodium (DSS). This protocol update describes an adaptation of the existing protocol that modifies the technique. This protocol has been used to generate improved mouse models that better reflect the nature of IBDs in humans. In TNBS and oxazolone colitis models, topical administration of hapten reagents results in T-cell-mediated immunity against haptenized proteins and luminal antigens. By contrast, to generate DSS colitis models, mice orally receive DSS, causing death of epithelial cells, compromising barrier function and causing subsequent inflammation. The analysis of the acute colitis models can be performed within 1-2 weeks, whereas that of the chronic models may take 2-4 months. The strengths of the acute models are that they are based on the analysis of short-lasting barrier alterations, innate immune effects and flares. The advantages of the chronic models are that they may offer better insight into adaptive immunity and complications such as neoplasia and tissue fibrosis. The protocol requires basic skills in laboratory animal research.

Camptothecin and its analog SN-38, the active metabolite of irinotecan, inhibit binding of the transcriptional regulator and oncoprotein FUBP1 to its DNA target sequence FUSE.

The transcriptional regulator FUSE Binding Protein 1 (FUBP1) is overexpressed in more than 80% of all human hepatocellular carcinomas (HCCs) and other solid tumor entities including prostate and colorectal carcinoma. FUBP1 expression is required for HCC tumor cell expansion, and it functions as an important pro-proliferative and anti-apoptotic oncoprotein that binds to the single-stranded DNA sequence FUSE to regulate the transcription of a variety of target genes. In this study, we screened an FDA-approved drug library and discovered that the Topoisomerase I (TOP1) inhibitor camptothecin (CPT) and its derivative 7-ethyl-10-hydroxycamptothecin (SN-38), the active irinotecan metabolite that is used in the clinics in combination with other chemotherapeutics to treat carcinoma, inhibit FUBP1 activity. Both molecules prevent in vitro the binding of FUBP1 to its single-stranded target DNA FUSE, and they induce deregulation of FUBP1 target genes in HCC cells. Our results suggest the interference with the FUBP1/FUSE interaction as a further molecular mechanism that, in addition to the inactivation of TOP1, may contribute to the therapeutic potential of CPT/SN-38. Targeting of FUBP1 in HCC therapy with SN-38/irinotecan could be a particularly interesting option because of the high FUBP1 levels in HCC cells and their dependency on FUBP1 expression.

Elevated levels of Bcl-3 inhibits Treg development and function resulting in spontaneous colitis.

Bcl-3 is an atypical NF-κB family member that regulates NF-κB-dependent gene expression in effector T cells, but a cell-intrinsic function in regulatory T (Treg) cells and colitis is not clear. Here we show that Bcl-3 expression levels in colonic T cells correlate with disease manifestation in patients with inflammatory bowel disease. Mice with T-cell-specific overexpression of Bcl-3 develop severe colitis that can be attributed to defective Treg cell development and function, leading to the infiltration of immune cells such as pro-inflammatory γδT cells, but not αß T cells. In Treg cells, Bcl-3 associates directly with NF-κB p50 to inhibit DNA binding of p50/p50 and p50/p65 NF-κB dimers, thereby regulating NF-κB-mediated gene expression. This study thus reveals intrinsic functions of Bcl-3 in Treg cells, identifies Bcl-3 as a potential prognostic marker for colitis and illustrates the mechanism by which Bcl-3 regulates NF-κB activity in Tregs to prevent colitis.

A Stat6/Pten Axis Links Regulatory T Cells with Adipose Tissue Function.

Obesity and type 2 diabetes are associated with metabolic defects and adipose tissue inflammation. Foxp3+ regulatory T cells (Tregs) control tissue homeostasis by counteracting local inflammation. However, if and how T cells interlink environmental influences with adipocyte function remains unknown. Here, we report that enhancing sympathetic tone by cold exposure, beta3-adrenergic receptor (ADRB3) stimulation or a short-term high-calorie diet enhances Treg induction in vitro and in vivo. CD4+ T cell proteomes revealed higher expression of Foxp3 regulatory networks in response to cold or ADRB3 stimulation in vivo reflecting Treg induction. Specifically, Ragulator-interacting protein C17orf59, which limits mTORC1 activity, was upregulated in CD4+ T cells by either ADRB3 stimulation or cold exposure, suggesting contribution to Treg induction. By loss- and gain-of-function studies, including Treg depletion and transfers in vivo, we demonstrated that a T cell-specific Stat6/Pten axis links cold exposure or ADRB3 stimulation with Foxp3+ Treg induction and adipose tissue function. Our findings offer a new mechanistic model in which tissue-specific Tregs maintain adipose tissue function.

IL-9 regulates intestinal barrier function in experimental T cell-mediated colitis.

As previous studies suggested that IL-9 may control intestinal barrier function, we tested the role of IL-9 in experimental T cell-mediated colitis induced by the hapten reagent 2,4,6-trinitrobenzenesulfonic acid (TNBS). The deficiency of IL-9 suppressed TNBS-induced colitis and led to lower numbers of PU.1 expressing T cells in the lamia propria, suggesting a regulatory role for Th9 cells in the experimental TNBS colitis model. Since IL-9 is known to functionally alter intestinal barrier function in colonic inflammation, we assessed the expression of tight junction molecules in intestinal epithelial cells of TNBS-inflamed mice. Therefore we made real-time PCR analyses for tight junction molecules in the inflamed colon from wild-type and IL-9 KO mice, immunofluorescent stainings and investigated the expression of junctional proteins directly in intestinal epithelial cells of TNBS-inflamed mice by Western blot studies. The results demonstrated that sealing proteins like occludin were up regulated in the colon of inflamed IL-9 KO mice. In contrast, the tight junction protein Claudin1 showed lower expression levels when IL-9 is absent. Surprisingly, the pore-forming molecule Claudin2 revealed equal expression in TNBS-treated wild-type and IL-9-deficient animals. These results illustrate the pleiotropic functions of IL-9 in changing intestinal permeability in experimental colitis. Thus, modulation of IL-9 function emerges as a new approach for regulating barrier function in intestinal inflammation.

Single-Stranded DNA-Binding Transcriptional Regulator FUBP1 Is Essential for Fetal and Adult Hematopoietic Stem Cell Self-Renewal.

The ability of hematopoietic stem cells (HSCs) to self-renew is a prerequisite for the establishment of definitive hematopoiesis and life-long blood regeneration. Here, we report the single-stranded DNA-binding transcriptional regulator far upstream element (FUSE)-binding protein 1 (FUBP1) as an essential factor of HSC self-renewal. Functional inactivation of FUBP1 in two different mouse models resulted in embryonic lethal anemia at around E15.5 caused by severely diminished HSCs. Fetal and adult HSCs lacking FUBP1 revealed an HSC-intrinsic defect in their maintenance, expansion, and long-term blood reconstitution, but could differentiate into all hematopoietic lineages. FUBP1-deficient adult HSCs exhibit significant transcriptional changes, including upregulation of the cell-cycle inhibitor p21 and the pro-apoptotic Noxa molecule. These changes caused an increase in generation time and death of HSCs as determined by video-microscopy-based tracking. Our data establish FUBP1 and its recognition of single-stranded genomic DNA as an important element in the transcriptional regulation of HSC self-renewal.