134 resultados para interleukins
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Pós-graduação em Bases Gerais da Cirurgia - FMB
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Pós-graduação em Bases Gerais da Cirurgia - FMB
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Aims: Development of effective immune-based therapies for patients with non-small-cell lung carcinoma (NSCLC) depends on an accurate characterization of complex interactions that occur between immune cells and the tumour environment. Methods and results: Innate and adaptive immune responses were evaluated in relation to prognosis in 65 patients with surgically excised NSCLC. Immunohistochemistry and morphometry were used to determine the abundance and distribution of immune cells. We found low numbers of immune cells and levels of cytokines in the tumour environment when compared with surrounding parenchyma. Smoking was associated inversely with the adaptive immune response and directly with innate immunity. We observed a prominent adaptive immune response in squamous cell carcinomas (SCC) but greater innate immune responses in adenocarcinomas and large cell carcinomas. Cox model analysis showed a low risk of death for smoking <41 packs/year, N-0 tambour stage, squamous carcinoma, CD4(+) > 16.81% and macrophages/monocytes >4.5%. Collectively, the data indicate that in NSCLC there is not a substantive local immune cell infiltrate within the tumour. Conclusion: Although immune cell infiltration is limited in NSCLC it appears to have an impact on prognosis and this may be of relevance for new immunotherapeutic approaches.
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Background and Objectives Transfusion-related acute lung injury (TRALI) is characterized by leukocyte transmigration and alveolar capillary leakage shortly after transfusion. TRALI pathogenesis has not been fully elucidated. In some cases, the infusion of alloantibodies (immune model), whereas in others the combination of neutrophil priming by proinflammatory molecules with the subsequent infusion of biological response modifiers (BRMs) in the hemocomponent (non-immune model) have been implicated. Our aim was to compare the pathological events involved in TRALI induced by antibodies or BRMs using murine models. Materials and Methods In the immune model, human HNA-2+ neutrophils were incubated in vitro with a monoclonal antibody (anti-CD177, clone 7D8) directed against the HNA-2 antigen and injected i.v. in NOD/SCID mice. In the non-immune model, BALB/c mice were treated with low doses of lipopolysaccharide (LPS) followed by platelet-activating factor (PAF) infusion 2 h later. Forty minutes after PAF administration, or 6 h after neutrophil injection, lungs were isolated and histological analysis, determination of a variety of cytokines and chemokines including keratinocyte-derived chemokine (KC), MIP-2, the interleukins IL-1 beta, IL-6, IL-8 as well as TNFa, cell influx and alveolar capillary leakage were performed. Results In both models, characteristic histological findings of TRALI and an increase in KC and MIP-2 levels were detected. In contrast to the immune model, in the non-immune model, there was a dramatic increase in IL-1 beta and TNFa. However, capillary leakage was only detected if PAF was administrated. Conclusions Regardless of the triggering event(s), KC, MIP-2 and integrins participate in TRALI pathogenesis, whereas PAF is essential for capillary leakage when two events are involved.
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The gut microbiota (GM) is essential for human health and contributes to several diseases; indeed it can be considered an extension of the self and, together with the genetic makeup, determines the physiology of an organism. In this thesis has been studied the peripheral immune system reconstitution in pediatric patients undergoing allogeneic hematopoietic stem cell transplantation (aHSCT) in the early phase; in parallel, have been also explored the gut microbiota variations as one of the of primary factors in governing the fate of the immunological recovery, predisposing or protecting from complications such as the onset of acute graft-versus-host disease (GvHD). Has been demonstrated, to our knowledge for the first time, that aHSCT in pediatric patients is associated to a profound modification of the GM ecosystem with a disruption of its mutualistic asset. aGvHD and non-aGvHD subjects showed differences in the process of GM recovery, in members abundance of the phylum Bacteroidetes, and in propionate fecal concentration; the latter are higher in the pre-HSCT composition of non-GvHD subjects than GvHD ones. Short-chain fatty acids (SCFAs), such as acetate, butyrate and propionate, are end-products of microbial fermentation of macronutrients and distribute systemically from the gut to blood. For this reason, has been studied their effect in vitro on human DCs, the key regulators of our immune system and the main player of aGvHD onset. Has been observed that propionate and, particularly, butyrate show a strong and direct immunomodulatory activity on DCs reducing inflammatory markers such as chemokines and interleukins. This study, with the needed caution, suggests that the pre-existing GM structure can be protective against aGvHD onset, exerting its protective role through SCFAs. They, indeed, may regulate cell traffic within secondary lymphoid tissues, influence T cell development during antigen recognition, and, thus, directly shape the immune system.
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INTRODUCTION: The purpose of this study was to investigate the adhesion and invasion of periodontopathogenic bacteria in varied mixed infections and the release of interleukins from an epithelial cell line (KB cells). METHODS: KB cells were co-cultured with Porphyromonas gingivalis ATCC 33277 and M5-1-2, Tannerella forsythia ATCC 43037, Treponema denticola ATCC 35405 and Fusobacterium nucleatum ATCC 25586 in single and mixed infections. The numbers of adherent and internalized bacteria were determined up to 18 h after bacterial exposure. Additionally, the mRNA expression and concentrations of released interleukin (IL)-6 and IL-8 were measured. RESULTS: All periodontopathogenic bacteria adhered and internalized in different numbers to KB cells, but individually without any evidence of co-aggregation also to F. nucleatum. High levels of epithelial mRNA of IL-6 and IL-8 were detectable after all bacterial challenges. After the mixed infection of P. gingivalis ATCC 33277 and F. nucleatum ATCC 25586 the highest levels of released interleukins were found. No IL-6 and IL-8 were detectable after the mixed infection of P. gingivalis M5-1-2 and F. nucleatum ATCC 25586 and the fourfold infection of P. gingivalis ATCC 33277, T. denticola ATCC 35405, T. forsythia ATCC 43037 and F. nucleatum ATCC 25586. CONCLUSION: Anaerobic periodontopathogenic bacteria promote the release of IL-6 and IL-8 by epithelial cells. Despite a continuous epithelial expression of IL-8 mRNA by all bacterial infections these effects are temporary because of the time-dependent degradation of cytokines by bacterial proteases. Mixed infections have a stronger virulence potential than single bacteria. Further research is necessary to evaluate the role of mixed infections and biofilms in the pathogenesis of periodontitis.
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The production of epithelial neutrophil activating peptide-78 (NA-78) and the interleukins IL-8 and IL-6 by endometrial stromal cells is stimulated by pro-inflammatory interleukin-1 (IL-1) and tumour necrosis factor-α (TNF-α). IL-8 is suggested to play a role in the pathogenesis of endometriosis, and in these women the peritoneal fluid concentrations of ENA-78 and IL-8 are increased. TNF-α has been tested together with interferon-γ because of their cooperative stimulation of IL-6. The release of IL-8, however, is inhibited with increasing interferon levels. The aim of the study was the analysis of the production of ENA-78, IL-6 and IL-8 by cultured human endometrial stromal cells in the presence of varying concentrations of IL-1β, TNF-α, and interferon-γ.
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BACKGROUND: Psoriasis is a chronic immune-mediated skin disease, in which interleukins 12 and 23 have been postulated to play a critical role. However, the cellular source of these cytokines in psoriatic lesions are still poorly defined and their relative contribution in inducing skin inflammation has been discussed controversially. OBJECTIVES: To investigate immunoreactivity of the bioactive forms of IL-12 and IL-23 in plaque psoriasis and to characterize the dendritic cell (DC) and macrophage subsets responsible for the production of these cytokines. METHODS: Immunohistochemistry was performed on normal skin (n=11) as well as non-lesional (n=11) and lesional (n=11) skin of patients with plaque psoriasis using monoclonal antibodies targeting the bioactive forms of IL-12 (IL-12p70) and IL-23 (IL-23p19/p40) on serial cryostat sections using the alkaline phosphatase-antialkaline phosphatase. Co-localization of IL-12 and IL-23 with different dendritic cells and macrophage cell markers (CD1a, CD11c, CD14, CD32, CD68, CD163, CD208/DC-LAMP) was performed using double immunofluorescence staining. RESULTS: Immunoreactivity for IL-12 and IL-23 was significantly enhanced in lesional psoriatic skin as compared to non-lesional and normal skin. No difference was observed between IL-12 and IL-23 immunoreactivity in any skin types. Both IL-12 and IL-23 immunoreactivity was readily detected mainly in CD11c+, CD14+, CD32+, CD68+ and some CD163+, DC-LAMP+ cells. IL-12 and occasionally IL-23 were also found in some CD1a+ dendritic cells. In addition, an enhanced expression mainly of IL-23 was observed in keratinocytes. CONCLUSIONS: Bioactive forms of IL-12 and IL-23 are highly expressed in various DC and macrophage subsets and their marked in situ production suggest that both cytokines have crucial pathogenic role in psoriasis.
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Acute infection with the hepatitis C virus (HCV) induces a wide range of innate and adaptive immune responses. A total of 20-50% of acutely HCV-infected individuals permanently control the virus, referred to as 'spontaneous hepatitis C clearance', while the infection progresses to chronic hepatitis C in the majority of cases. Numerous studies have examined host genetic determinants of hepatitis C infection outcome and revealed the influence of genetic polymorphisms of human leukocyte antigens, killer immunoglobulin-like receptors, chemokines, interleukins and interferon-stimulated genes on spontaneous hepatitis C clearance. However, most genetic associations were not confirmed in independent cohorts, revealed opposing results in diverse populations or were limited by varying definitions of hepatitis C outcomes or small sample size. Coordinated efforts are needed in the search for key genetic determinants of spontaneous hepatitis C clearance that include well-conducted candidate genetic and genome-wide association studies, direct sequencing and follow-up functional studies.
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Recurrent airway obstruction (RAO), or heaves, is a naturally occurring asthma-like disease that is related to sensitisation and exposure to mouldy hay and has a familial basis with a complex mode of inheritance. A genome-wide scanning approach using two half-sibling families was taken in order to locate the chromosome regions that contribute to the inherited component of this condition in these families. Initially, a panel of 250 microsatellite markers, which were chosen as a well-spaced, polymorphic selection covering the 31 equine autosomes, was used to genotype the two half-sibling families, which comprised in total 239 Warmblood horses. Subsequently, supplementary markers were added for a total of 315 genotyped markers. Each half-sibling family is focused around a severely RAO-affected stallion, and the phenotype of each individual was assessed for RAO and related signs, namely, breathing effort at rest, breathing effort at work, coughing, and nasal discharge, using an owner-based questionnaire. Analysis using a regression method for half-sibling family structures was performed using RAO and each of the composite clinical signs separately; two chromosome regions (on ECA13 and ECA15) showed a genome-wide significant association with RAO at P < 0.05. An additional 11 chromosome regions showed a more modest association. This is the first publication that describes the mapping of genetic loci involved in RAO. Several candidate genes are located in these regions, a number of which are interleukins. These are important signalling molecules that are intricately involved in the control of the immune response and are therefore good positional candidates.
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Restoration of the tumor-suppression function by gene transfer of the melanoma differentiation-associated gene 7 (MDA7)/interleukin 24 (IL-24) successfully induces apoptosis in melanoma tumors in vivo. To address the molecular mechanisms involved, we previously revealed that MDA7/IL-24 treatment of melanoma cells down-regulates interferon regulatory factor (IRF)-1 expression and concomitantly up-regulates IRF-2 expression, which competes with the activity of IRF-1 and reverses the induction of IRF-1-regulated inducible nitric oxide synthase (iNOS). Interferons (IFNs) influence melanoma cell survival by modulating apoptosis. A class I IFN (IFN-alpha) has been approved for the treatment of advanced melanoma with some limited success. A class II IFN (IFN-gamma), on the other hand, supports melanoma cell survival, possibly through constitutive activation of iNOS expression. We therefore conducted this study to explore the molecular pathways of MDA7/IL-24 regulation of apoptosis via the intracellular induction of IFNs in melanoma. We hypothesized that the restoration of the MDA7/IL-24 axis leads to upregulation of class I IFNs and induction of the apoptotic cascade. We found that MDA7/IL-24 induces the secretion of endogenous IFN-beta, another class I IFN, leading to the arrest of melanoma cell growth and apoptosis. We also identified a series of apoptotic markers that play a role in this pathway, including the regulation of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Fas-FasL. In summary, we described a novel pathway of MDA7/IL-24 regulation of apoptosis in melanoma tumors via endogenous IFN-beta induction followed by IRF regulation and TRAIL/FasL system activation.
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BACKGROUND Recurrent urticaria (RU) is a common skin disease of horses, but little is known about its pathogenesis. HYPOTHESIS/OBJECTIVE The aim of this study was to characterize the inflammatory cell infiltrate and cytokine expression pattern in the skin of horses with RU. ANIMALS Biopsies of lesional and nonlesional skin of horses with RU (n = 8) and of skin from healthy control horses (n = 8) were evaluated. METHODS The inflammatory cell infiltrate was analysed by routine histology. Immunohistochemistry was used to identify T cells (CD3), B ells (CD79), macrophages (MAC387) and mast cells (tryptase). Expression of T-helper 2 cytokines (interleukins IL-4, IL-5 and IL-13), a T-helper 1 cytokine (interferon-γ), IL-4 receptor α and thymic stromal lymphopoietin was assessed by quantitative RT-PCR. Results - In subepidermal lesional skin of RU-affected horses, increased numbers of eosinophils (P ≤ 0.01), CD79-positive (P ≤ 0.01), MAC387-positive (P ≤ 0.01) and tryptase-positive cells (P ≤ 0.05) were found compared with healthy horses. Subepidermal lesional skin of RU-affected horses contained more eosinophils (P ≤ 0.05) and tryptase-positive cells (P ≤ 0.05) compared with nonlesional skin. There was no significant difference in infiltrating cells between nonlesional skin and skin of healthy horses. Expression of IL-4 (P ≤ 0.01), IL-13 (P ≤ 0.05), thymic stromal lymphopoietin (P ≤ 0.05) and IL-4 receptor α (P ≤ 0.05) was increased in lesional skin of RU-affected horses compared with control horses. Expression of IL-4 was higher (P ≤ 0.05) in lesional compared with nonlesional RU skin. CONCLUSIONS AND CLINICAL IMPORTANCE Analysis of cytokine expression and inflammatory infiltrate suggests that T-helper 2 cytokines, eosinophils, mast cells and presumptive macrophages play a role in the pathogenesis of equine RU.
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PROBLEM Given the important role of regulatory T cells (Treg) for successful pregnancy, the ability of soluble maternal and fetal pregnancy factors to induce human Treg was investigated. METHOD OF STUDY Peripheral blood mononuclear cells (PBMCs) or isolated CD4+CD25‒ cells were cultured in the presence of pooled second or third trimester pregnancy sera, steroid hormones or supernatants from placental explants, and the numbers and function of induced CD4+CD25+FOXP3+ Treg were analysed. RESULTS Third trimester pregnancy sera and supernatants of early placental explants, but not sex steroid hormones, induced an increase of Tregs from PBMCs. Early placental supernatant containing high levels of tumour necrosis factor-α, interferon-γ, interleukins -1, -6 and -17, soluble human leucocyte antigen-G, and transforming growth factor-β1, increased the proportion of Treg most effectively and was able to induce interleukin-10-secreting-Treg from CD4+CD25‒cells. CONCLUSIONS Compared with circulating maternal factors, placental- and fetal-derived factors appear to exert a more powerful effect on numerical changes of Treg, thereby supporting fetomaternal tolerance during human pregnancy.