Elevated Expression Of Pro-inflammatory Cytokines Research Articles

Anti-inflammatory properties of bone morphogenetic protein 4 in human adipocytes.

Obesity is characterized by increased adipocyte number and size as well as white adipose tissue (WAT) inflammation, which is fundamental for the development of insulin resistance and type-2 diabetes. These processes, regulated by various endocrine, paracrine and autocrine factors, are extensively studied with the hope to interfere and to inhibit weight gain and related complications in obese patients. Recent data suggest an important role of bone morphogenic protein 4 (BMP4) in the regulation of adipogenesis and development of obesity. BMP4 is a growth factor of the transforming growth factor-β superfamily. Initially, BMPs were identified as inducers of ectopic bone formation. It is now apparent, however, that these proteins have different pleiotropic developmental actions and including playing a role in white adipogenesis. Here, we demonstrate that the expression of BMP4 in human WAT is negatively correlated to body mass index and to the expression of pro-inflammatory cytokines. In vitro, BMP4 expression in cultured human adipocytes is upregulated after induction of differentiation. Cells treated with exogenous BMP4 increased peroxisome proliferator-activated receptor γ (PPARγ) expression and significantly reduced the expression of pro-inflammatory cytokines including tumor necrosis factor α (TNF-α) and monocyte chemoattractant protein 1. TNF-α treatment of fully differentiated adipocytes resulted in downregulation of the expression of adipogenic genes and elevated expression of pro-inflammatory cytokines. Exogenous BMP4 addition significantly reduced the negative effect of TNF-α on the expression profile of adipocytes. Finally, treatment of human adipocytes with exogenous BMP4 reduced the adipocytes' chemoattractant potential and the migration of monocytes toward adipocyte-conditioned medium. These results indicate that BMP4 is an important anti-inflammatory molecule, which may act through PPARγ and reduces TNF-α-mediated pro-inflammatory cytokine production in human adipocytes. Through its anti-inflammatory potential, BMP4 may serve as a protective factor for inflammation-related diseases such as insulin-tolerance or type-2 diabetes.

Sex dimorphism in periodontitis in animal models.

Although surveys in the USA have shown that male subjects are more prone to develop periodontitis, sex as a risk factor in periodontitis, and its mechanism, remain controversial. Animal models are ideal for investigating immunological mechanisms of sex dimorphism in periodontitis because in these models it is possible to exclude the interference of gender-related risk factors, such as smoking and oral hygiene habits. Based on surveys in humans and reports on sex dimorphism in other diseases, our hypothesis is that sex is a risk factor in periodontitis. Different murine models (oral gavage model and ligature model) for periodontitis have been utilized to determine susceptibility to periodontitis in female and male mice. Periodontal bone levels were measured as the distance from the cemento-enamel junction to the alveolar bone crest (CEJ-ABC) in young female or male mice (8-10wk of age). Differential expression of inflammatory mediators in the gingivae of female and male mice was determined by quantitative real-time PCR. In comparison with male mice, female mice displayed significantly (p<0.05) increased periodontal bone loss, accompanied by elevated expression of proinflammatory cytokines (interleukin-1β, interleukin-6 and interleukin-17A) and higher numbers of oral bacteria. In contrast to the results in humans, in which periodontitis susceptibility is also influenced by confounding gender-related behaviors, in the murine oral gavage model and ligature model, female mice appear to be more susceptible to periodontal bone loss than male mice. In the ligature model, we observed significantly (p<0.05) higher CEJ-ABC distance, gingival proinflammatory cytokine production and number of oral bacteria in female mice. Furthermore, our results imply that female mice develop periodontitis with a higher progression rate. Our study has therefore established that animal models can be used to dissect the mechanisms underlying genuine gender-based differences in periodontal disease susceptibility and/or progression.

TLR-3 is present in human adipocytes, but its signalling is not required for obesity-induced inflammation in adipose tissue in vivo.

Innate immunity plays a pivotal role in obesity-induced low-grade inflammation originating from adipose tissue. Key receptors of the innate immune system including Toll-like receptors-2 and -4 (TLRs) are triggered by nutrient excess to promote inflammation. The role of other TLRs in this process is largely unknown. In addition to double-stranded viral mRNA, TLR-3 can also recognize mRNA from dying endogenous cells, a process that is frequently observed within obese adipose tissue. Here, we identified profound expression of TLR-3 in adipocytes and investigated its role during diet-induced obesity. Human adipose tissue biopsies (n=80) and an adipocyte cell-line were used to study TLR-3 expression and function. TLR-3-/- and WT animals were exposed to a high-fat diet (HFD) for 16 weeks to induce obesity. Expression of TLR-3 was significantly higher in human adipocytes compared to the non-adipocyte cells part of the adipose tissue. In vitro, TLR-3 expression was induced during differentiation of adipocytes and stimulation of the receptor led to elevated expression of pro-inflammatory cytokines. In vivo, TLR-3 deficiency did not significantly influence HFD-induced obesity, insulin sensitivity or inflammation. In humans, TLR-3 expression in adipose tissue did not correlate with BMI or insulin sensitivity (HOMA-IR). Together, our results demonstrate that TLR-3 is highly expressed in adipocytes and functionally active. However, TLR-3 appears to play a redundant role in obesity-induced inflammation and insulin resistance.

Sulforaphane Reduces Inflammatory Gene Expression in Microglia from Aged Mice

Increased oxidative stress resulting from heightened microglial activation is associated with age‐related cognitive impairment, neurodegenerative disease, and response to immune stimulus. The primary compensatory mechanism for neutralizing oxidative stress is through the nuclear factor E2‐related factor 2 (Nrf2) pathway which regulates transcription of antioxidant response element (ARE) genes. Here, BV2 cells and brain CD11b+ microglial cells isolated from young adult and aged mice were used to investigate the effects of sulforaphane (SFN), a potent Nrf2‐inducing bioactive, on ARE and inflammatory gene expression associated with increased age. We hypothesized that SFN would upregulate ARE genes in primary microglial cells and that this would attenuate elevated proinflammatory cytokine expression in microglia from aged mice. In support of our hypothesis, SFN upregulated antioxidant genes NAD(P)H dehydrogenase, quinone 1 (NQO1), heme oxygenase‐1 (HMOX1), and the modulatory subunit of glutamate‐cysteine ligase, modifier subunit (GCLM) in BV2 cells and primary microglia. Primary microglia from aged mice had higher expression of interleukin (IL‐)1β, IL‐6, and inducible nitric oxide synthase (iNOS) than adult controls, and SFN reduced IL‐1β and iNOS in microglia from aged mice. Taken together these data indicate that SFN is a potential therapeutic supplement that may be beneficial for reducing microglia‐mediated neuroinflammation and oxidative stress associated with aging.Supported by NIH RO1AG16710

Ndfip1 regulates itch ligase activity and airway inflammation via UbcH7.

The ubiquitin-ligating enzyme (E3) Itch plays a crucial role in the regulation of inflammation, and Itch deficiency leads to severe airway inflammation. However, the molecular mechanisms by which Itch function is regulated remain elusive. In this study, we found that nontypeable Haemophilus influenzae induces the association of Itch with Ndfip1. Both Itch(-/-) and Ndfip1(-/-) mice exhibited severe airway inflammation in response to nontypeable Haemophilus influenza, which was associated with elevated expression of proinflammatory cytokines. Ndfip1 enhanced Itch ligase activity and facilitated Itch-mediated Tak1 ubiquitination. Mechanistically, Ndfip1 facilitated recruitment of ubiquitin-conjugating enzyme (E2) UbcH7 to Itch. The N-terminal region of Ndfip1 binds to UbcH7, whereas the PY motif binds to Itch. Hence, Ndfip1 acts as an adaptor for UbcH7 and Itch. Reconstitution of full-length Ndfip1 but not the mutants that fail to interact with either UbcH7 or Itch, restored the defect in Tak1 ubiquitination and inhibited elevated proinflammatory cytokine expression by Ndfip1(-/-) cells. These results provide new mechanistic insights into how Itch function is regulated during inflammatory signaling, which could be exploited therapeutically in inflammatory diseases.

CD8+ T cell profiles in patients with rheumatoid arthritis and their relationship to disease activity.

CD8+ T cells are abundant in rheumatoid arthritis (RA). However, their role in disease pathogenesis is poorly defined. This study was undertaken to investigate the relationship between disease activity and CD8+ T cell phenotypes, production of cytokines, and production of cytotoxic molecules in the peripheral blood (PB) and synovial fluid (SF) of patients with RA. CD8+ T cell phenotypes were determined in 96 patients with RA (44 with disease in remission, 34 with active disease, 18 with low disease activity) and in 64 sex- and age-matched healthy controls. Ten paired PB and SF samples from patients with active RA were analyzed. The expression of surface markers, cytokines, and proteolytic enzymes in CD8+ T cells was evaluated using flow cytometry. PB CD8+ T cells from RA patients with active disease exhibited an effector (CD27-CD62L-) phenotype (P = 0.005), with elevated expression of proinflammatory cytokines (tumor necrosis factor α [TNFα], interferon-γ [IFNγ], interleukin-6 [IL-6], IL-17A) when compared to healthy controls. In a state of remission, the same phenotype observed in patients with active disease persisted, including a significant increase in the frequency of CD69 (P < 0.001), but lower cytokine production was observed. SF CD8+ T cells from RA patients expressed more robust effector memory (CD27+CD62L-) and activated (CD69+) profiles compared to the T cell subsets in paired PB samples. Production of cytokines (IL-6, IL-17A, and IFNγ) by CD8+ T cells from RA PB was positively correlated within individual donors. Moreover, production of cytokines (TNFα, IFNγ, and IL-17A) by CD8+ T cells from RA PB positively correlated with the Disease Activity Score in 28 joints. The activation status and proinflammatory potential of CD8+ T cell subsets observed in the RA patients in this study strongly suggest that a phenotype of local and systemic cytotoxic effector T cells plays a role in this disease.

Mice fed fish oil diet and upregulation of brown adipose tissue thermogenic markers.

Fish oil (FO) elicits diverse beneficial effects. Reduction in or prevention of body mass (BM) gain in animal models may be associated with modulation of brown adipose tissue (BAT). We aimed to evaluate the effects of different high-fat diets with FO on BAT metabolism and thermogenic markers. C57BL/6 male mice (3-month-old) were fed different diets during 8 weeks: standard-chow diet (SC 10% fat), high-fat lard diet (HF-L 50% fat), high-fat lard plus FO diet (HF-L+FO 50% fat), and high-fat FO diet (HF-FO 50% fat). We evaluated BM and performed an oral glucose tolerance test. At euthanasia, plasma was collected for leptin, and triacylglycerol measurement and interscapular BAT was dissected and stored for molecular analyses. HF-L group showed elevated BM; glucose intolerance associated with diminished TC10 and GLUT4 expressions; hypertriglyceridemia associated with increased CD36 and diminished CPT1 expression; elevated expression of pro-inflammatory cytokines; and reduced PPAR expression. Furthermore, these animals showed hyperleptinemia with increased expression of thermogenic markers (beta3-AR, PGC1alpha, and UCP1). Conversely, HF-L+FO and HF-FO groups showed reduced BM gain with regularization of glucose tolerance and triglyceridemia, GLUT4, TC10, CD36, CPT1, and cytokines expressions. Both groups exhibited elevated PPAR and thermogenic markers expression in a dose-dependent way. FO improves metabolic profile and upregulates thermogenic markers, suggesting an elevated thermogenesis that leads to reduced BM gain.

Adenosine Regulates the Proinflammatory Signaling Function of Thrombin in Endothelial Cells

The plasma level of the regulatory metabolite adenosine increases during the activation of coagulation and inflammation. Here we investigated the effect of adenosine on modulation of thrombin-mediated proinflammatory responses in HUVECs. We found that adenosine inhibits the barrier-disruptive effect of thrombin in HUVECs by a concentration-dependent manner. Analysis of cell surface expression of adenosine receptors revealed that A2A and A2B are expressed at the highest level among the four receptor subtypes (A2B > A2A > A1 > A3 ) on HUVECs. The barrier-protective effect of adenosine in response to thrombin was recapitulated by the A2A specific agonist, CGS 21680, and abrogated both by the siRNA knockdown of the A2A receptor and by the A2A -specific antagonists, ZM-241385 and SCH-58261. The thrombin-induced RhoA activation and its membrane translocation were both inhibited by adenosine in a cAMP-dependent manner, providing a molecular mechanism through which adenosine exerts a barrier-protective function. Adenosine also inhibited thrombin-mediated activation of NF-κB and decreased adhesion of monocytic THP-1 cells to stimulated HUVECs via down-regulation of expression of cell surface adhesion molecules, VCAM-1, ICAM-1, and E-selectin. Moreover, adenosine inhibited thrombin-induced elevated expression of proinflammatory cytokines, IL-6 and HMGB-1; and chemokines, MCP-1, CXCL-1, and CXCL-3. Taken together, these results suggest that adenosine may inhibit thrombin-mediated proinflammatory signaling responses, thereby protecting the endothelium from injury during activation of coagulation and inflammation.

Rotavirus acceleration of murine type 1 diabetes is associated with increased MHC class I-restricted antigen presentation by B cells and elevated proinflammatory cytokine expression by T cells

Rotavirus infection has been proposed to enhance progression towards type 1 diabetes in at-risk children. Rhesus monkey rotavirus (RRV) accelerates diabetes onset in non-obese diabetic (NOD) and T cell receptor transgenic NOD8.3 mice. Infected NOD mice show virus spread to pancreatic lymph nodes (PLN) and mesenteric lymph nodes (MLN), induction of a serum T helper 1-biased specific antibody response and proinflammatory cytokine mRNA expression in PLN and islets. Here, we analysed the effects of RRV infection on intestinal responses and the activation of antigen presenting cells (APC), T cells and B cells in PLN, MLN, spleen and islets. Diabetes acceleration by RRV was associated with minimal immune activation in Peyer's patches. Increased proinflammatory cytokine expression by APC, including dendritic cells, was observed exclusively in the PLN, while cytokine expression by T cells was detected in islets, PLN, MLN and spleen. RRV infection of NOD8.3 mice increased IFNγ expression by CD8+ T cells, which primarily recognise an islet autoantigen. A peptide corresponding to RRV VP7 amino acids 5–13, with sequence similarity to this islet autoantigen, did not induce activation or proliferation of NOD8.3 mouse T cells. RRV infection of NOD mice elevated B cell MHC I expression in PLN and MLN, and increased the B cell-mediated proliferation of islet antigen-specific CD8+ T cells. These studies demonstrate that RRV infection of NOD mice activates APC, T cells and B cells at sites where autoreactive lymphocytes accumulate, in association with proinflammatory cytokine expression and an increased capacity to present antigen. Taken together with previous findings, these data support a possible role for bystander activation in type 1 diabetes acceleration by RRV.

Does Nrf2 Gene Transfer Facilitate Recovery After Contusion Spinal Cord Injury?

Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) modulates gene expression in response to oxidative damage in neurodegenerative diseases, including spinal cord injury (SCI). We noticed that activation of Nrf2 pathway persists for an extended time after clinically relevant contusion model of SCI. Injured Nrf2(-/-) mice were impaired in hindlimb function, exhibited increased atrophy, demyelination, and astrogliosis of the SC concomitant with altered expression of genes controlling apoptosis, inflammation, and neurotrophic factors suggesting the importance of Nrf2 for recovery. We used lentiviral gene transfer to increase Nrf2 expression and improve functional recovery after SCI. Although the transferred Nrf2 was expressed in neurons and astrocytes, we noticed hindlimb function impairment and elevated expression of pro-inflammatory cytokines as an adverse effect. These toxic effects were not reduced by including Nrf2 in the lentiviral vector. Augmenting the amount of delivered Nrf2 gene diminished toxic effects of the lentivirus, yet was not sufficient to improve functional recovery. Results of this study lead to the hypothesis that Nrf2 plays a crucial and multifaceted role in recovery from SCI, but even high overexpression of Nrf2 in injured SC may not offer extra benefit, providing protection only against lentivirus-induced toxicity that is manifested in the SC.

Role of cytokines and Jak3/Stat3 signaling in the 1,2-dimethylhydrazine dihydrochloride-induced rat model of colon carcinogenesis

The molecular mechanisms by which colon cancer cells regulate the expression of various proinflammatory and anti-inflammatory cytokines and transcription factors resulting in tumor progression have not been well clarified. The present study thus explores the effect of cancer cell-derived cytokines and transcription factors on the chemoprevention of a rat model of early colon carcinogenesis. Elevated expression of proinflammatory cytokines [interleukin-1β (IL-1β), IL-2, interferon γ, and tumor necrosis factor-α] and the transcription factors [Janus kinase 3 (Jak3) and signal transducer and activator of transcription 3 (Stat3)] was found in the 1,2-dimethylhydrazine dihydrochloride (DMH) group; however, this elevated expression was reversed by the individual and combination treatment with piroxicam, a traditional nonsteroidal anti-inflammatory drug [inhibiting both cyclooxygenase-1 (COX-1) and COX-2] and c-phycocyanin, a cyanobacterium-derived biliprotein from Spirulina platensis (selective COX-2 inhibitor). In the DMH group, low expression of IL-4, an anti-inflammatory cytokine, was further observed with respect to the other groups. Expression of inducible nitric oxide synthase and nitric oxide/citrulline levels was also analyzed and was found to be elevated with DMH treatment. Increased apoptotic index and stimulated levels of Bcl-2-associated death promoter (Bad), a proapoptotic protein, were observed in piroxicam-treated and c-phycocyanin-treated rats. In-silico molecular docking of piroxicam as a ligand with several regulatory proteins was performed, indicating that, except inducible nitric oxide synthase, it effectively binds with COX-1, COX-2, Jak3, and Stat3. Piroxicam and c-phycocyanin perhaps showed chemopreventive properties by inhibiting proinflammatory cytokines and Jak3/Stat3 signaling while promoting apoptosis. In addition, a combination regimen was found to be more beneficial than monotherapy.

Abstract 1544: Control of tumor-associated macrophage alternative activation by MIF.

Abstract Tumor stromal alternatively activated macrophages are important determinants of anti-tumor T lymphocyte responses, intratumoral neovascularization and metastatic dissemination. Our recent efforts to investigate the mechanism of macrophage migration inhibitory factor (MIF) in antagonizing anti-melanoma immune responses reveal that macrophage-derived MIF is necessary for maximal macrophage alternative activation in melanoma-bearing mice. Both peripheral and tumor-associated macrophages (TAMs) isolated from melanoma bearing MIF-deficient mice display elevated pro-inflammatory cytokine expression and reduced anti-inflammatory, immunosuppressive and pro-angiogenic gene products compared to macrophages from tumor bearing MIF wildtype mice. Moreover, TAMs and myeloid-derived suppressor cells (MDSCs) from MIF-deficient mice exhibit reduced T lymphocyte immunosuppressive activities than do those from their wildtype littermates. Corresponding with reduced tumor immunosuppression and neoangiogenic potential by TAMs, MIF-deficiency confers protection against transplantable subcutaneous melanoma outgrowth and melanoma lung metastatic colonization. Finally, we report for the first time that our previously discovered MIF small molecule antagonist, 4-iodo-6-phenylpyrimidine (4-IPP), recapitulates MIF-deficiency in vitro and in vivo and attenuates tumor polarized macrophage alternative activation, immunosuppression, neoangiogenesis and melanoma tumor outgrowth. These studies are the first to describe a functional contribution by MIF to tumor-associated macrophage alternative activation and provide justification for immunotherapeutic targeting of MIF in melanoma patients. Citation Format: Kavitha Yaddanapudi, Kalyani Putty, Beatriz Rendon, Gwyneth Lamont, Jonathan Faughn, Robert Mitchell. Control of tumor-associated macrophage alternative activation by MIF. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1544. doi:10.1158/1538-7445.AM2013-1544

Control of Tumor-Associated Macrophage Alternative Activation by Macrophage Migration Inhibitory Factor

Tumor stromal alternatively activated macrophages are important determinants of antitumor T lymphocyte responses, intratumoral neovascularization, and metastatic dissemination. Our recent efforts to investigate the mechanism of macrophage migration inhibitory factor (MIF) in antagonizing antimelanoma immune responses reveal that macrophage-derived MIF participates in macrophage alternative activation in melanoma-bearing mice. Both peripheral and tumor-associated macrophages (TAMs) isolated from melanoma bearing MIF-deficient mice display elevated proinflammatory cytokine expression and reduced anti-inflammatory, immunosuppressive, and proangiogenic gene products compared with macrophages from tumor-bearing MIF wild-type mice. Moreover, TAMs and myeloid-derived suppressor cells from MIF-deficient mice exhibit reduced T lymphocyte immunosuppressive activities compared with those from their wild-type littermates. Corresponding with reduced tumor immunosuppression and neo-angiogenic potential by TAMs, MIF deficiency confers protection against transplantable s.c. melanoma outgrowth and melanoma lung metastatic colonization. Finally, we report for the first time, to our knowledge, that our previously discovered MIF small molecule antagonist, 4-iodo-6-phenylpyrimidine, recapitulates MIF deficiency in vitro and in vivo, and attenuates tumor-polarized macrophage alternative activation, immunosuppression, neoangiogenesis, and melanoma tumor outgrowth. These studies describe an important functional contribution by MIF to TAM alternative activation and provide justification for immunotherapeutic targeting of MIF in melanoma patients.

The role of PPARγ in carbon nanotube-elicited granulomatous lung inflammation

BackgroundAlthough granulomatous inflammation is a central feature of many disease processes, cellular mechanisms of granuloma formation and persistence are poorly understood. Carbon nanoparticles, which can be products of manufacture or the environment, have been associated with granulomatous disease. This paper utilizes a previously described carbon nanoparticle granuloma model to address the issue of whether peroxisome proliferator-activated receptor gamma (PPARγ), a nuclear transcription factor and negative regulator of inflammatory cytokines might play a role in granulomatous lung disease. PPARγ is constitutively expressed in alveolar macrophages from healthy individuals but is depressed in alveolar macrophages of patients with sarcoidosis, a prototypical granulomatous disease. Our previous study of macrophage-specific PPARγ KO mice had revealed an intrinsically inflammatory pulmonary environment with an elevated pro-inflammatory cytokines profile as compared to wild-type mice. Based on such observations we hypothesized that PPARγ expression would be repressed in alveolar macrophages from animals bearing granulomas induced by MWCNT instillation.MethodsWild-type C57Bl/6 and macrophage-specific PPARγ KO mice received oropharyngeal instillations of multiwall carbon nanotubes (MWCNT) (100 μg). Bronchoalveolar lavage (BAL) cells, BAL fluids, and lung tissues were obtained 60 days post-instillation for analysis of granuloma histology and pro-inflammatory cytokines (osteopontin, CCL2, and interferon gamma [IFN-γ] mRNA and protein expression.ResultsIn wild-type mice, alveolar macrophage PPARγ expression and activity were significantly reduced in granuloma-bearing animals 60 days after MWCNT instillation. In macrophage-specific PPARγ KO mice, granuloma formation was more extensive than in wild-type at 60 days after MWCNT instillation. PPARγ KO mice also demonstrated elevated pro-inflammatory cytokine expression in lung tissue, laser-microdissected lung granulomas, and BAL cells/fluids, at 60 days post MWCNT exposure.ConclusionsOverall, data indicate that PPARγ deficiency promotes inflammation and granuloma formation, suggesting that PPARγ functions as a negative regulator of chronic granulomatous inflammation.

TL1A/DR3 interaction is associated with pathogenesis of inflammatory bowel disease in adults and children

Event Abstract Back to Event TL1A/DR3 interaction is associated with pathogenesis of inflammatory bowel disease in adults and children Tomasz J. Slebioda1*, Piotr M. Wierzbicki1, Marcin Stanislawowski1, Krzysztof Celinski2, Piotr Landowski3, Barbara Kaminska3, Agnieszka Bojarska-Junak4, Jacek Rolinski4, Krystian Adrych5 and Zbigniew Kmiec6 1 Medical University of Gdansk, Department of Histology, Poland 2 Medical University of Lublin, Department of Gastroenterology with Endoscopic Unit, Poland 3 Medical Univesrity of Gdansk, Department of Pediatrics, Pediatric Gastroenterology, Hepatology and Nutrition, Poland 4 Medical University of Lublin, Department of Clinical Immunology, Poland 5 Medical University of Gdansk, Department of Gastroenterology and Hepatology, Poland 6 University of Warmia and Mazury, Department of Human Histology and Embryology, Poland TL1A is a proinflammatory cytokine and the ligand for death receptor 3 (DR3). These proteins are strongly up-regulated on activated cells of the immune system. TL1A/DR3 interaction costimulates T-cells and induces production of several proinflammatory cytokines (including IL-4, IL-13, IL-17A, IFN-γ) by these cells. TL1A and DR3 are linked to the development of Crohn’s disease (CD) and ulcerative colitis (UC), although their exact pathological role remains unknown. In this study, we investigated the mRNA level of TL1A, IL-4, IL-13, IL-17A and IFN-γ in colon mucosal biopsies of paediatric and adult inflammatory bowel disease (IBD) patients. We found that expression of TL1A was significantly elevated in inflamed but not in non-inflamed colonic tissue of both CD and UC patients as compared to healthy individuals. Interestingly, we detected up-regulation of DR3 only in inflamed colonic tissue of paediatric but not adult patients. Up-regulation of TL1A mRNA was accompanied by elevated expression of proinflammatory cytokines and positively correlated with the expression level of IL-17A mRNA in inflamed and non-inflamed tissue of both paediatric and adult UC patients. Furthermore, TL1A and DR3 protein expression was localized by immunohistochemical technique not only to mucosa-infiltrating mononuclear cells but also to enterocytes. Our study also provides evidence for the first time that TL1A mRNA expression is significantly higher while DR3 mRNA expression is significantly lower in healthy adults compared to healthy children. These findings show that TL1A contributes to the development of IBD via induction of IL-17A expression and this observation may have therapeutic implications. Keywords: TL1A, inflammatory bowel disease, DR3, TNFSF15, Inflammation, IL17A Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Immune-mediated disease pathogenesis Citation: Slebioda TJ, Wierzbicki PM, Stanislawowski M, Celinski K, Landowski P, Kaminska B, Bojarska-Junak A, Rolinski J, Adrych K and Kmiec Z (2013). TL1A/DR3 interaction is associated with pathogenesis of inflammatory bowel disease in adults and children. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.00153 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 11 Mar 2013; Published Online: 22 Aug 2013. * Correspondence: Dr. Tomasz J Slebioda, Medical University of Gdansk, Department of Histology, Gdansk, Poland, t.slebioda@gumed.edu.pl Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Tomasz J Slebioda Piotr M Wierzbicki Marcin Stanislawowski Krzysztof Celinski Piotr Landowski Barbara Kaminska Agnieszka Bojarska-Junak Jacek Rolinski Krystian Adrych Zbigniew Kmiec Google Tomasz J Slebioda Piotr M Wierzbicki Marcin Stanislawowski Krzysztof Celinski Piotr Landowski Barbara Kaminska Agnieszka Bojarska-Junak Jacek Rolinski Krystian Adrych Zbigniew Kmiec Google Scholar Tomasz J Slebioda Piotr M Wierzbicki Marcin Stanislawowski Krzysztof Celinski Piotr Landowski Barbara Kaminska Agnieszka Bojarska-Junak Jacek Rolinski Krystian Adrych Zbigniew Kmiec PubMed Tomasz J Slebioda Piotr M Wierzbicki Marcin Stanislawowski Krzysztof Celinski Piotr Landowski Barbara Kaminska Agnieszka Bojarska-Junak Jacek Rolinski Krystian Adrych Zbigniew Kmiec Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. 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Oral polio vaccination failure in urban slum children is associated with malnutrition and evidence of chronic inflammation (166.2)

Abstract Oral vaccines for polio (OPV) and rotavirus have been shown to be much less effective in poor children in the developing world. The reason(s) for oral vaccine failure in this setting has been unknown. We hypothesized that failure of orally administered vaccines such as OPV was due to tropical enteropathy and resultant inflammation from endotoxin exposure. We tested this hypothesis in a cohort of children followed from birth in an urban slum of Dhaka Bangladesh. Response to oral poliovirus vaccine was measured in the children who received the recommended minimum of three doses of OPV by age 6 months. Diminished antibody responses to OPV were associated with malnutrition, serum endotoxin-specific antibodies, and shorter breastfeeding duration. In a subset of these children, we investigated the mechanism for vaccine failure using a systems-immunology approach, performing comprehensive cellular assays on peripheral blood mononuclear cells, including a single-cell mass-spectrometry based assessment of cellular phenotypes and functional capacities. From this analysis, children with vaccine failure exhibited globally reduced cellular responsiveness to a range of cytokine stimulations, as well as elevated pro-inflammatory cytokine expression. These data indicate that oral vaccine failure in this at-risk group is related to malnutrition, gut barrier dysfunction and shorter duration of breast-feeding in early childhood, and is associated with a chronic inflammatory immune phenotype.

Palmitate-Activated Macrophages Confer Insulin Resistance to Muscle Cells by a Mechanism Involving Protein Kinase C θ and ε

BackgroundMacrophage-derived factors contribute to whole-body insulin resistance, partly by impinging on metabolically active tissues. As proof of principle for this interaction, conditioned medium from macrophages treated with palmitate (CM-PA) reduces insulin action and glucose uptake in muscle cells. However, the mechanism whereby CM-PA confers this negative response onto muscle cells remains unknown.Methodology/Principal FindingsL6-GLUT4myc myoblasts were exposed for 24 h to palmitate-free conditioned medium from RAW 264.7 macrophages pre-treated with 0.5 mM palmitate for 6 h. This palmitate-free CM-PA, containing selective cytokines and chemokines, inhibited myoblast insulin-stimulated insulin receptor substrate 1 (IRS1) tyrosine phosphorylation, AS160 phosphorylation, GLUT4 translocation and glucose uptake. These effects were accompanied by a rise in c-Jun N-terminal kinase (JNK) activation, degradation of Inhibitor of κBα (IκBα), and elevated expression of proinflammatory cytokines in myoblasts. Notably, CM-PA caused IRS1 phosphorylation on Ser1101, and phosphorylation of novel PKCθ and ε. Co-incubation of myoblasts with CM-PA and the novel and conventional PKC inhibitor Gö6983 (but not with the conventional PKC inhibitor Gö6976) prevented PKCθ and ε activation, JNK phosphorylation, restored IκBα mass and reduced proinflammatory cytokine production. Gö6983 also restored insulin signalling and glucose uptake in myoblasts. Moreover, co-silencing both novel PKC θ and ε isoforms in myoblasts by RNA interference, but not their individual silencing, prevented the inflammatory response and restored insulin sensitivity to CM-PA-treated myoblasts.Conclusions/Clinical SignificanceThe results suggest that the block in muscle insulin action caused by CM-PA is mediated by novel PKCθ and PKCε. This study re-establishes the participation of macrophages as a relay in the action of fatty acids on muscle cells, and further identifies PKCθ and PKCε as key elements in the inflammatory and insulin resistance responses of muscle cells to macrophage products. Furthermore, it portrays these PKC isoforms as potential targets for the treatment of fatty acid-induced, inflammation-linked insulin resistance.

Persistent rheumatic musculoskeletal pain and disorders at one year post-chikungunya epidemic in south Maharashtra—a rural community based observational study with special focus on naïve persistent rheumatic musculoskeletal cases and selected cytokine expression

The recent Chikungunya (CHIKV) epidemic (2006) unleashed an unrecognized spectrum of rheumatic musculoskeletal (RMSK) pain and disorders. The data on persistent RMSK is lacking. About 10% clinical acute cases are considered to suffer from chronic arthritis. We used an arthritis camp approach in a 9000 populated village Modnimb (district Sholapur) in December 2007 to identify naive cases of RMSK following symptomatic CHIKV outbreak in December 2006. A 10-day intensive publicity through public announcement and media pamphlet distribution program was carried out to attract villagers with persistent aches and pains and a past history of acute CHIKV illness to attend a 3 day free of cost evaluation arthritis camps. Blood samples were collected from consenting patients. Village volunteers and health workers participated in it. 1.4 percent (95% confidence interval 1.13, 1.60) village population was found to suffer from naive persistent RMSK pain and disorders at 1 year following acute CHIKV infection. Patients were generally >45 years age and females were predominant. Knee was the predominant pain site in 79% cases. Though 27% cases suffered from non-specific arthralgias (NSA), the diagnosis in 48% and 15% cases respectively was consistent with OA (often knee and spine) and undifferentiated inflammatory arthritis (0.2% crude prevalence). Overall, the clinical RMSK profile was benign and none reported any significant functional disability or mobility impairment. Seventy-three percent patients tested seropositive for anti-CHIKV IgG antibody; none for IgM antibody. None showed any abnormality on routine laboratory haematology and biochemistry testing; seropositive RF, ANA and anti-CCP was infrequent. Though CRP values were low, IL-6 was elevated and was not associated with any clinical phenotype. As compared to normal healthy population values assayed a year prior to the epidemic in a neighboring village, cases with persistent RMSK showed elevated IFN-γ, TNF-α and IL-13. Also, the clinical phenotype and cytokine expression did not seem to differ between the seropositive and seronegative groups for anti-CIKV IgG antibody. Conclusion In this rural community study, at least 1.4% population continued to suffer from some form of RMSK at 1 year following acute CHIKV epidemic. Though clinically unimpressive, a large number showed elevated pro-inflammatory cytokine expression. A longer follow-up may explain this disconnect.

Elevated proinflammatory cytokine expression in affected skin in small fiber neuropathy

Small fiber neuropathy (SFN) is a subtype of sensory neuropathy with acral pain and normal findings in routine nerve conduction studies. Twenty-four patients with SFN and matched controls were prospectively studied in this case-control study. Patients were assessed clinically, with standardized pain and depression questionnaires, by neurophysiologic tests, and by quantitative sensory testing. All patients underwent skin punch biopsy in a clinically affected (distal calf) and a nonaffected area (proximal thigh). Blood samples were collected for systemic cytokine gene expression analysis. Patients with SFN had a 2-fold higher gene expression for interleukin (IL)-2 (p < 0.0001), IL-10 (p = 0.01), and transforming growth factor-beta1 (p = 0.001) in peripheral blood. Skin samples from affected areas showed increased IL-6 (7-fold; p = 0.001) and IL-8 (5-fold; p = 0.002) gene expression when compared to healthy controls. In 10/24 patients, SFN was termed length-dependent (LD) because of a > or =5-fold higher intraepidermal nerve fiber density in the proximal than in the distal skin. Patients with LD-SFN had higher gene expression in the affected distal skin than in nonaffected skin for tumor necrosis factor-alpha (2.6-fold; p = 0.04), IL-1beta (2-fold; p = 0.02), IL-6 (>200-fold; p = 0.01), and IL-8 (>500-fold; p = 0.046). Inflammatory cells were present in most SFN samples but their numbers were not correlated with cytokine levels. Elevated local proinflammatory cytokines may be involved in the pathophysiology of pain in length-dependent small fiber neuropathy. These findings suggest a potential therapeutic role of locally applied cytokine inhibitors.

Periodontal inflammation and bone loss in aged mice

Young mice do not develop measurable periodontal bone loss, unless heavily infected with human periodontal pathogens. However, mice with a genetically altered immune system are unable to control their own oral flora and develop periodontitis early in life. Based on the potential of the indigenous oral microbiota to cause periodontitis, we hypothesized that normal mice may ultimately develop inflammatory periodontal bone loss, i.e. as a function of age. If confirmed, this could serve as an aging model of chronic periodontitis. Periodontal bone levels were measured as the distance from the cementoenamel junction to the alveolar bone crest in young mice (8-10 wk of age), old mice (>or= 18 mo of age) and mice of intermediate ages. Differential expression of inflammatory mediators in the gingivae of young and old mice was determined by quantitative real-time PCR. In comparison with young mice, old mice displayed significantly (p < 0.05) increased periodontal bone loss, accompanied by elevated expression of proinflammatory cytokines (interleukin-1 beta, tumor necrosis factor alpha and interleukin-17A) and innate immune receptors involved in the induction or amplification of inflammation (Toll-like receptor 2, CD14, CD11b, CD18, complement C5a receptor and triggering receptor expressed on myeloid cells 3). Mice develop naturally induced periodontal bone loss as a function of age. This aging model of periodontitis represents a genuinely chronic model to study mechanisms of periodontal tissue destruction.