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Intracellular Cytokine Staining (intracellular + cytokine_staining)
Selected AbstractsExpression of CD8, identifies a distinct subset of effector memory CD4+ T lymphocytesIMMUNOLOGY, Issue 2 2006Iole Macchia Summary Circulating CD4+ CD8+ T lymphocytes have been described in the peripheral blood of humans and several animal species. However, the origin and functional properties of these cells remain poorly understood. In the present study, we evaluated the frequency, phenotype and function of peripheral CD4+ CD8+ T cells in rhesus macaques. Two distinct populations of CD4+ CD8+ T cells were identified: the dominant one was CD4hi CD8lo and expressed the CD8,, homodimer, while the minor population was CD4lo CD8hi and expressed the CD8,, heterodimer. The majority of CD4hi CD8,lo T cells exhibited an activated effector/memory phenotype (CCR5lo CD7, CD28, HLA-DR+) and expressed relatively high levels of granzyme B. Intracellular cytokine staining assays demonstrated that the frequency of cytomegalovirus-specific T cells was enriched five-fold in CD4hi CD8,lo T cells compared to single-positive CD4+ T cells, whereas no consistent enrichment was observed for simian immunodeficiency virus (SIV)-specific T cells. Cross-sectional studies of SIV-infected animals demonstrated that the frequency of CD4hi CD8,lo T cells was lower in wild-type SIV-infected animals compared to uninfected controls, although prospective studies of SIV-infected animals demonstrated depletion of CD4hi CD8,lo lymphocytes only in a subset of animals. Taken together, these data suggest that CD4+ T cells expressing CD8, represent an effector/memory subset of CD4+ T cells and that this cell population can be depleted during the course of SIV infection. [source] PAN,DR-Binding Hsp60 self epitopes induce an interleukin-10,mediated immune response in rheumatoid arthritisARTHRITIS & RHEUMATISM, Issue 7 2009Huib de Jong Objective Human Hsp60 is expressed in the joints of patients with rheumatoid arthritis (RA) and can elicit a regulatory T cell response in the peripheral blood and synovial fluid. However, Hsp60 can also trigger strong proinflammatory pathways. Thus, to understand the nature of these Hsp60-directed responses in RA, it is necessary to study such responses at the molecular, epitope-specific level. This study was undertaken to characterize the disease specificity and function of pan,DR-binding Hsp60,derived epitopes as possible modulators of autoimmune inflammation in RA. Methods Lymphocyte proliferation assays (using 3H-thymidine incorporation and carboxyfluorescein diacetate succinimidyl ester [CFSE] staining) and measurement of cytokine production (using multiplex immunoassay and intracellular staining) were performed after in vitro activation of peripheral blood mononuclear cells from patients with RA, compared with healthy controls. Results A disease (RA),specific immune recognition, characterized by T cell proliferation as well as increased production of tumor necrosis factor , (TNF,), interleukin-1, (IL-1,), and IL-10, was found for 3 of the 8 selected peptides in patients with RA as compared with healthy controls (P < 0.05). Intracellular cytokine staining and CFSE labeling showed that CD4+ T cells were the subset primarily responsible for both the T cell proliferation and the cytokine production in RA. Interestingly, the human peptides had a remarkably different phenotype, with a 5,10-fold higher IL-10:TNF, ratio, compared with that of the microbial peptides. Conclusion These results suggest a disease-specific immune-modulatory role of epitope-specific T cells in the inflammatory processes of RA. Therefore, these pan,DR-binding epitopes could be used as a tool to study the autoreactive T cell response in RA and might be suitable candidates for use in immunotherapy. [source] Infection of mice with the helminth Strongyloides stercoralis suppresses pulmonary allergic responses to ovalbuminCLINICAL & EXPERIMENTAL ALLERGY, Issue 3 2001Chun-Chi Wang Asthma and helminth infections induce similar immune responses characterized by the presence of peripheral blood eosinophilia and elevated serum IgE levels. Epidemiological surveys have reported either increases or decreases in the development of atopic diseases and asthma based on the prevalence of helminth infections in the population. The aim of this study was to determine if a pre-existing helminth infection would increase or decrease subsequent allergic responses to an unrelated allergen in the lungs. BALB/cByJ mice were infected with the nematode parasite Strongyloides stercoralis prior to ovalbumin (OVA) immunization and intratracheal challenge. Bronchoalveolar lavage (BAL) and fluid (BALF) were collected 3 days post-challenge and cellular and humoral immune responses were measured. Intracellular cytokine staining revealed increased IL-4 and IL-5 producing cells in BAL from mice infected with S. stercoralis before OVA sensitization. Increased IL-5 protein levels and decreased IFN-, protein levels were also observed in the BALF. There was, however, no increase in airway eosinophil accumulation in mice infectd with parasites before sensitization with OVA as compared to mice exposed to OVA alone. Furthermore, eotaxin levels in the lungs induced by OVA was suppressed in mice infected with the parasite before OVA sensitization. The development of OVA specific IgE responses in BALF was also impaired in mice infected with the parasite before sensitization with OVA. These results suggest that a pre-existing helminth infection may potentiate a systemic Type 2-type response yet simultaneously suppress in the lungs allergen-specific IgE responses and eotaxin levels in response to subsequent exposure to allergens. [source] Interleukin-10-secreting T cells define a suppressive subset within the HIV-1-specific T-cell populationEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 5 2009Eirik A. Torheim Abstract Recent studies have indicated that Treg contribute to the HIV type 1 (HIV-1)-related immune pathogenesis. However, it is not clear whether T cells with suppressive properties reside within the HIV-1-specific T-cell population. Here, PBMC from HIV-1-infected individuals were stimulated with a 15-mer Gag peptide pool, and HIV-1-specific T cells were enriched by virtue of their secretion of IL-10 or IFN-, using immunomagnetic cell-sorting. Neither the IL-10-secreting cells nor the IFN-,-secreting cells expressed the Treg marker FOXP3, yet the IL-10-secreting cells potently suppressed anti-CD3/CD28-induced CD4+ as well as CD8+ T-cell proliferative responses. As shown by intracellular cytokine staining, IL-10- and IFN-,-producing T cells represent distinct subsets of the HIV-1-specific T cells. Our data collectively suggest that functionally defined HIV-1-specific T-cell subsets harbor potent immunoregulatory properties that may contribute to HIV-1-associated T-cell dysfunction. [source] Inflammation and drug hepatotoxicity: Aggravation of injury or clean-up mission?,HEPATOLOGY, Issue 5 2005Hartmut Jaeschke BACKGROUND & AIMS Inflammatory mediators released by nonparenchymal inflammatory cells in the liver have been implicated in the progression of acetaminophen (APAP) hepatotoxicity. Among hepatic nonparenchymal inflammatory cells, we examined the role of the abundant natural killer (NK) cells and NK cells with T-cell receptors (NKT cells) in APAP-induced liver injury. METHODS C57BL/6 mice were administered a toxic dose of APAP intraperitoneally to cause liver injury with or without depletion of NK and NKT cells by anti-NK1.1 monoclonal antibody (MAb). Serum alanine transaminase (ALT) levels, liver histology, hepatic leukocyte accumulation, and cytokine/chemokine expression were assessed. RESULTS Compared with APAP-treated control mice, depletion of both NK and NKT cells by anti-NK1.1 significantly protected mice from APAP-induced liver injury, as evidenced by decreased serum ALT level, improved survival of mice, decreased hepatic necrosis, inhibition of messenger RNA (mRNA) expression for interferon-gamma (IFN-gamma), Fas ligand (FasL), and chemokines including KC (Keratinocyte-derived chemokine); MIP-1 alpha (macrophage inflammatory protein-1 alpha); MCP-1 (monocyte chemoattractant protein-1); IP-10 (interferon-inducible protein); Mig (monokine induced by IFN-gamma) and decreased neutrophil accumulation in the liver. Hepatic NK and NKT cells were identified as the major source of IFN-gamma by intracellular cytokine staining. APAP induced much less liver injury in Fas-deficient (lpr) and FasL-deficient (gld) mice compared with that in wild-type mice. CONCLUSIONS NK and NKT cells play a critical role in the progression of APAP-induced liver injury by secreting IFN-gamma, modulating chemokine production and accumulation of neutrophils, and up-regulating FasL expression in the liver, all of which may promote the inflammatory response of liver innate immune system, thus contributing to the severity and progression of liver injury downstream of the metabolism of APAP and depletion of reduced glutathione (GSH) in hepatocytes. [source] Incubation phase of acute hepatitis B in man: Dynamic of cellular immune mechanismsHEPATOLOGY, Issue 5 2000George J.M. Webster After hepatitis B virus (HBV) infection, liver injury and viral control have been thought to result from lysis of infected hepatocytes by virus-specific cytotoxic T cells. Patients are usually studied only after developing significant liver injury, and so the viral and immune events during the incubation phase of disease have not been defined. During a single-source outbreak of HBV infection, we identified patients before the onset of symptomatic hepatitis. The dynamics of HBV replication, liver injury, and HBV-specific CD8+ and CD4+ cell responses were investigated from incubation to recovery. Although a rise in alanine transaminase (ALT) levels was present at the time of the initial fall in HBV-DNA levels, maximal reduction in virus level occurred before significant liver injury. Direct ex vivo quantification of HBV-specific CD4+ and CD8+ cells, by using human leukocyte antigen (HLA) class I tetramers and intracellular cytokine staining, showed that adaptive immune mechanisms are present during the incubation phase, at least 4 weeks before symptoms. The results suggest that the pattern of reduction in HBV replication is not directly proportional to tissue injury during acute hepatitis B in humans. Furthermore, because virus-specific immune responses and significant reductions in viral replication are seen during the incubation phase, it is likely that the immune events central to viral control occur before symptomatic disease. [source] Virological and immunological features of active cytomegalovirus infection in nonimmunosuppressed patients in a surgical and trauma intensive care unit,JOURNAL OF MEDICAL VIROLOGY, Issue 8 2010Marifina Chilet Abstract Cytomegalovirus (CMV) reactivation occurs frequently in critically ill patients. The natural course of CMV infection and the interaction between CMV and the adaptive immune system in this setting remain poorly defined. Fifty-three CMV-seropositive patients in a surgical and trauma intensive care unit were included in this study. The CMV DNA load in tracheal aspirates (TA) and plasma (PL) was monitored by qPCR. CMV-specific T-cell immunity was assessed by intracellular cytokine staining. Plasma TNF-, levels were determined by ELISA. CMV reactivation occurred in 39.7% of patients (23% had CMV DNA detected only in TA). The analysis of TA allowed an earlier diagnosis in 28% of patients. Clearance of CMV DNAemia preceded that of CMV DNA in TA in some episodes. Peak CMV DNA levels were significantly higher in TA than in PL (P,=,0.02). CMV reactivation developed in the presence of CMV-specific T cells. Termination of CMV reactivation was associated with an expansion of functional CMV-specific T cells. Plasma levels of TNF-, did not allow for the prediction of the occurrence of CMV reactivation. CMV-specific T-cell immunity is preserved in most critically ill patients experiencing CMV reactivation. Analysis of respiratory specimens is imperative for an optimal monitoring of CMV reactivation in this setting. J. Med. Virol. 82:1384,1391, 2010. © 2010 Wiley-Liss, Inc. [source] Impact of changes in antigen level on CD38/PD-1 co-expression on HIV-specific CD8 T cells in chronic, untreated HIV-1 infection,,JOURNAL OF MEDICAL VIROLOGY, Issue 3 2010Thomas Vollbrecht Abstract Excessive immune activation is a hallmark of chronic uncontrolled HIV infection. During the past years, growing evidence suggests that immune inhibitory signals also play an important role in progressive disease. However, the relationship between positive and negative immune signals on HIV-specific CD8 T cells has not been studied in detail so far in chronic HIV-1 infection. In this study, the expression of markers of positive (CD38) and negative (PD-1) immune signals on virus-specific CD8 T cells in chronic, untreated HIV-1 infection was evaluated using intracellular cytokine staining. Viral escape mutations were assessed by autologous virus sequence analysis and subsequent peptide titration assays. Single-epitope CD8 T-cell responses toward Gag, Pol, and Nef were compared in 12 HIV-1 controllers (viral load <5,000,cp/ml) and 12 HIV-1 progressors (viral load >50,000,cp/ml) and a highly significant increase of CD38/PD-1 co-expression on virus-specific CD8 T cells in progressors was found (P,<,0.0001). The level of CD38/PD-1 co-expression was independent of epitope specificity. Longitudinal follow-up revealed a clear drop in CD38/PD-1 co-expression on virus-specific CD8 T cells after the suppression of antigen following either viral escape mutation or the initiation of HAART (P,=,0.004). Antigen persistence with a fluctuating viral load revealed stable levels of CD38/PD-1 co-expression whereas significant rises in viral load were accompanied or even preceded by substantial increases in CD38/PD-1 co-expression. The CD38/PD-1 phenotype clearly distinguishes HIV-specific CD8 T-cell responses between controllers and progressors. Whether it plays a causative role in disease progression remains debatable. J. Med. Virol. 82:358,370, 2010. © 2010 Wiley-Liss, Inc. [source] Dissection of the CMV specific T-cell response is required for optimized cardiac transplant monitoring,JOURNAL OF MEDICAL VIROLOGY, Issue 9 2008Alexander Kirchner Abstract Despite the success of antivirals in preventing clinically overt CMV disease in cardiac allograft recipients, sub-clinical active CMV infection remains a major concern because of its association with allograft rejection and vasculopathy. The measurement of CMV specific T-cell responses is a promising approach to assessing this situation. For simplicity, class-I MHC/peptide-multimers staining CD8 T-cells directly are often used but this ignores a much wider range of responses including the whole CD4 T-cell compartment. CD4 T-cells, however, were recently shown to be critical to reducing CMV load early after transplantation. To determine how extensive T-cell responses to CMV are, the responses to two dominant CMV proteins, IE-1 and pp65, were dissected in detail accounting for T-cell lineage, frequencies, epitope recognition and changes over time in more than 25 heart transplant recipients. Cross-sectional results from over 30 healthy CMV-carriers were analyzed for comparison. Responses were unexpectedly complex, with considerable inter-individual variation in terms of dominance, breadth, and recognized epitopes. Whereas the use of MHC/peptide-multimers for clinical CD8 T-cell response monitoring alone can be justified in some situations, short term T-cell activation combined with intracellular cytokine staining was clearly found to be of more general usefulness. The performance of IFN-gamma, TNF-alpha, or IL-2 as single read-outs in identifying activated T-cells was examined and confirmed that the frequently used IFN-gamma was best suited. These results should be used to inform the design of clinically applicable and diagnostically useful approaches to monitoring CMV specific responses in heart transplant recipients. J. Med. Virol. 80:1604,1614, 2008. © 2008 Wiley-Liss, Inc. [source] Low-dose cyclosporine A therapy increases the regulatory T cell population in patients with atopic dermatitisALLERGY, Issue 11 2009C. Brandt Background:, Atopic dermatitis (AD) is a T cell dependent chronic relapsing inflammatory skin disorder successfully treated with cyclosporine A (CsA). Clinical observations indicate that even low-dose CsA therapy is successful in severely affected AD patients. We studied the impact of low-dose CsA therapy on the ability of T helper cells to be activated, and examined whether regulatory T (Treg) cells are increased in these patients. Methods:, Peripheral T cells were activated in a whole blood sample and interleukin-2 producing cells were measured by intracellular cytokine staining. Regulatory T cells were analyzed by intracellular FoxP3 staining. Regulatory T cells (CD4+CD25+CD127low) and effector T cells (CD4+CD25,CD127+) were sorted by flow cytometry and used for suppression assays. Results:, A group of AD patients treated with low-dose CsA had a significantly larger Treg cell population than a healthy control subject group. In individual patients, onset of low-dose CsA therapy reduced the ability of T cells to be activated to 42 ± 18% (P < 0.005) and significantly increased Treg cells, both in absolute numbers (1.6-fold change) and frequencies (1.7-fold change). Treg cells from AD patients showed similar suppressive capacities as Treg cells from healthy donors. Furthermore, Treg cells from AD patients had skin homing properties. Conclusion:, Our results indicate that the therapeutic effect of low-dose CsA therapy in AD patients might be not only mediated by the inhibition of T cell hyperactivity but also by an increased population of Treg cells. [source] ORIGINAL ARTICLE: Enhanced Maternal Anti-Fetal Immunity Contributes to the Severity of Hypertensive Disorder Complicating PregnancyAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2010Li-Ping Liu Citation Liu L-P, Huang W, Lu Y-C, Liao A-H. Enhanced maternal anti-fetal immunity contributes to the severity of hypertensive disorder complicating pregnancy. Am J Reprod Immunol 2010 Problem, The aim of this study was to evaluate how fetal monocyte activation and maternal anti-fetal antigen-specific antibody-secreting cells (ASC) affect the severity of hypertensive disorder complicating pregnancy (HDCP). Method of study, Forty-six healthy third-trimester pregnant women and 20 patients with gestational hypertension, 20 with mild pre-ecalmpsia and another 20 with severe pre-eclampsia were included in the study. Interleukin-6 (IL-6) release from cord blood monocytes was examined by intracellular cytokine staining and flow cytometric analysis. Moreover, the maternal anti-fetal antigen-specific ASC were detected by enzyme-linked immunospot assay. Results, A significantly increased percentage of IL-6-positive monocytes were detected in the cord blood of study groups compared with the controls (P < 0.01). The percentage of IL-6-positive monocytes was increased as the disease progressed (P < 0.05). There were more anti-fetal antigen-specific ASC in the study groups than those in the controls (P < 0.001). Furthermore, the anti-fetal antigen-specific ASC showed difference in gestational hypertensive and severe pre-eclamptic groups (P < 0.05). Conclusion, We conclude that the fetal monocyte activation and the increase in maternal anti-fetal antigen-specific ASC were related to the incidence and severity of HDCP. These results provide both indirect and direct evidence for the occurrence of exaggerated maternal humoral immunity against the fetal antigens in HDCP. [source] HLA,B27 misfolding and the unfolded protein response augment interleukin-23 production and are associated with Th17 activation in transgenic ratsARTHRITIS & RHEUMATISM, Issue 9 2009Monica L. DeLay Objective To determine whether HLA,B27 misfolding and the unfolded protein response (UPR) result in cytokine dysregulation and whether this is associated with Th1 and/or Th17 activation in HLA,B27/human ,2 -microglobulin (Hu,2m),transgenic rats, an animal model of spondylarthritis. Methods Cytokine expression in lipopolysaccharide (LPS),stimulated macrophages was analyzed in the presence and absence of a UPR induced by chemical agents or by HLA,B27 up-regulation. Cytokine expression in colon tissue and in cells purified from the lamina propria was determined by real-time reverse transcription,polymerase chain reaction analysis, and differences in Th1 and Th17 CD4+ T cell populations were quantified after intracellular cytokine staining. Results Interleukin-23 (IL-23) was found to be synergistically up-regulated by LPS in macrophages undergoing a UPR induced by pharmacologic agents or by HLA,B27 misfolding. IL-23 was also increased in the colon tissue from B27/Hu,2m-transgenic rats concurrently with the development of intestinal inflammation, and IL-17, a downstream target of IL-23, exhibited robust up-regulation in a similar temporal pattern. IL-23 and IL-17 transcripts were localized to CD11+ antigen-presenting cells and CD4+ T cells, respectively, from the colonic lamina propria. Colitis was associated with a 6-fold expansion of CD4+ IL-17,expressing T cells. Conclusion The IL-23/IL-17 axis is strongly activated in the colon of B27/Hu,2m-transgenic rats with spondylarthritis-like disease. HLA,B27 misfolding and UPR activation in macrophages can result in enhanced induction of the pro-Th17 cytokine IL-23. These results suggest a possible link between HLA,B27 misfolding and immune dysregulation in this animal model, with implications for human disease. [source] Effector CD8+ T cells in systemic sclerosis patients produce abnormally high levels of interleukin-13 associated with increased skin fibrosisARTHRITIS & RHEUMATISM, Issue 4 2009Patrizia Fuschiotti Objective T lymphocytes play an important role in systemic sclerosis (SSc), a connective tissue disease characterized by inflammation, fibrosis, and vascular damage. While their precise role and antigen specificity are unclear, T cell,derived cytokines likely contribute to the induction of fibrosis. The aim of this study was to establish the role of cytokine dysregulation by T cells in the pathogenesis of SSc. Methods To identify relationships between a specific cytokine, T cell subset, and the disease course, we studied a large cohort of patients with diffuse cutaneous SSc (dcSSc) or limited cutaneous SSc (lcSSc). Using Luminex analysis and intracellular cytokine staining, we analyzed the intrinsic ability of CD4+ and CD8+ T cell subsets to produce cytokines following in vitro activation. Results High levels of the profibrotic type 2 cytokine interleukin-13 (IL-13) were produced following activation of peripheral blood effector CD8+ T cells from SSc patients as compared with normal controls or with patients with rheumatoid arthritis. In contrast, CD4+ T cells showed a lower and more variable level of IL-13 production. This abnormality correlated with the extent of fibrosis and was more pronounced in dcSSc patients than in lcSSc patients. Conclusion Dysregulated IL-13 production by effector CD8+ T cells is important in the pathogenesis of SSc and is critical in the predisposition to more severe forms of cutaneous disease. Our study is the first to identify a specific T cell phenotype that correlates with disease severity in SSc and can be used as a marker of immune dysfunction in SSc and as a novel therapeutic target. [source] Promotion of the local differentiation of murine Th17 cells by synovial macrophages during acute inflammatory arthritisARTHRITIS & RHEUMATISM, Issue 12 2008Paul J. Egan Objective To examine the generation of proinflammatory Th17 cells at the site of tissue inflammation and in draining lymph nodes using an interleukin-17 (IL-17),dependent model of acute inflammatory arthritis. Methods Arthritis was elicited in mice by intraarticular injection of methylated bovine serum albumin (mBSA) into the knee and subcutaneous injection of IL-1,. Anti,IL-17 or control antibodies were administered during arthritis induction. Cytokine expression was evaluated by intracellular cytokine staining of synovial lymphocytes, by polymerase chain reaction analysis of RNA extracted from lymph node cells, and by enzyme-linked immunosorbent assay of cell culture supernatants. Th17 differentiation of naive CD4+ T cells was assessed in cocultures with macrophages from arthritic mice. Results Anti,IL-17 antibody administered during acute arthritis markedly reduced disease, indicating that the model is IL-17 dependent. IL-17 messenger RNA (mRNA), but not protein, was detected in draining lymph node CD4+ T cells and preceded joint inflammation. In addition, mRNA for Th17 cell,stimulatory cytokines (transforming growth factor ,, IL-6) and Th17 cell,inhibitory cytokines (interferon-,, IL-4) was detected in lymph nodes following injection of mBSA and IL-1,. Th17 cells were clearly identified in the inflamed synovium at the peak of disease. Synovial macrophages supported Th17 cell generation from naive CD4+ T cell precursors stimulated via CD3 in vitro and produced high levels of IL-6. In contrast, peritoneal macrophages failed to induce Th17 cell differentiation and produced less IL-6. Conclusion These results suggest that Th17 cell differentiation is initiated in draining lymph nodes but that IL-17,producing cells are restricted to the inflamed synovium, being generated in response to local cytokines produced by inflammatory macrophages. [source] Increased numbers of circulating polyfunctional Th17 memory cells in patients with seronegative spondylarthritidesARTHRITIS & RHEUMATISM, Issue 8 2008Camilla Jandus Objective A distinct subset of proinflammatory CD4+ T cells that produce interleukin-17 was recently identified. These cells are implicated in different autoimmune disease models, such as experimental autoimmune encephalomyelitis and collagen-induced arthritis, but their involvement in human autoimmune disease has not yet been clearly established. The purpose of this study was to assess the frequency and functional properties of Th17 cells in healthy donors and in patients with different autoimmune diseases. Methods Peripheral blood was obtained from 10 psoriatic arthritis (PsA), 10 ankylosing spondylitis (AS), 10 rheumatoid arthritis (RA), and 5 vitiligo patients, as well as from 25 healthy donors. Synovial tissue samples from a separate group of patients were also evaluated (obtained as paraffin-embedded sections). Peripheral blood cells were analyzed by multiparameter flow cytometry and immunohistochemistry. Cytokine production was examined by enzyme-linked immunosorbent assay and intracellular cytokine staining using specific monoclonal antibodies. Synovial tissue was examined for infiltrating T cells by immunohistochemical analysis. Results We found increased numbers of circulating Th17 cells in the peripheral blood of patients with seronegative spondylarthritides (PsA and AS), but not in patients with RA or vitiligo. In addition, Th17 cells from the spondylarthritis patients showed advanced differentiation and were polyfunctional in terms of T cell receptor,driven cytokine production. Conclusion These observations suggest a role of Th17 cells in the pathogenesis of certain human autoimmune disorders, in particular the seronegative spondylarthritides. [source] Elevated CD16 expression by monocytes from patients with tumor necrosis factor receptor,associated periodic syndromeARTHRITIS & RHEUMATISM, Issue 12 2007Ian Todd Objective Tumor necrosis factor receptor,associated periodic syndrome (TRAPS) is an inherited autosomal-dominant autoinflammatory condition caused by mutations in the ectodomain of the 55-kd tumor necrosis factor (TNF) receptor superfamily 1A. Proinflammatory blood monocytes with the phenotype CD14+,CD16+,HLA,DR++ are a major source of TNF, and the number of such monocytes is increased during infection and inflammation. The aim of this study was to investigate whether the expression of circulating CD16+ monocytes is affected in patients with TRAPS. Methods Peripheral blood obtained from patients with TRAPS and healthy control subjects was stained with monoclonal antibodies to detect CD14++,CD16, monocytes and CD14+,CD16+ monocytes, using flow cytometry. Lipopolysaccharide-induced TNF production was measured by intracellular cytokine staining. Activation-induced shedding of CD16 was investigated by treating blood samples with phorbol myristate acetate. Results The level of CD16 expression by CD14+,CD16+ monocytes, but not their absolute number, was significantly elevated in patients with TRAPS, even though the patients were not experiencing clinically overt episodes of autoinflammation at the time of sampling. These findings are similar to those for the C-reactive protein levels and erythrocyte sedimentation rates in the same patients. The enhanced level of CD16 expression by monocytes from patients with TRAPS was not attributable to a defect in activation-induced shedding of CD16. The CD14+,CD16+ monocytes were the predominant source of TNF in both patients and healthy control subjects. Conclusion The level of CD16 expression by monocytes was elevated in patients with TRAPS, as a feature of the underlying constitutive inflammation status. [source] Increased frequency of intracellular interleukin (IL)-13 and IL-10, but not IL-4, expressing CD4+ and CD8+ peripheral T cells of patients with atopic dermatitisBRITISH JOURNAL OF DERMATOLOGY, Issue 6 2002M. Aleksza Summary Background A number of studies exist demonstrating the increased expression of type 2 cytokines and decreased capacity to produce interferon-, (IFN-,) in peripheral blood mononuclear cells (PBMCs) of patients with atopic dermatitis (AD). Objectives To clarify the results of recent studies concerning the role of interleukin (IL)-4 and IL-13 in PBMCs of AD patients, we analysed the activation status of lymphocyte subpopulations. Methods We measured the intracellular expression and serum levels of certain type 1 and type 2 cytokines, using cell surface and intracellular cytokine staining, flow cytometry and enzyme-linked immunosorbent assay techniques. Results The frequency of IL-10 and IL-13 producing CD4+ and CD8+ T cells was significantly higher in patients with AD, while the frequency of IFN-, secreting helper and cytotoxic T cells was significantly lower in patients with AD than in control subjects. The serum levels of IL-10 and IL-13 were also significantly increased. There were no significant differences observed between the experimental groups in the frequency of IL-4 producing CD4+ and CD8+ cells. Conclusions This study demonstrates a type 2 cytokine production in the CD4+ and CD8+ T cells of AD patients, which is characterized by an elevated IL-13, but not by IL-4 secretion, and by an increased level of the immunoregulatory IL-10, which can contribute to a decrease in IFN-, expression. [source] Differential expansion, activation and effector functions of conventional and plasmacytoid dendritic cells in mouse tissues transiently infected with Listeria monocytogenesCELLULAR MICROBIOLOGY, Issue 7 2006Miguel A. Tam Summary Dendritic cells (DC) are crucial in generating immunity to infection. Here we characterize changes in DC in terms of number, activation and effector functions, focusing on conventional DC (cDC) and plasmacytoid DC (pDC), in Listeria -infected mice. Kinetic studies showed a subset- and tissue-specific expansion of cDC and upregulation of CD80 and CD86 on splenic and mesenteric lymph node (MLN) cDC after intragastric infection. Expansion of pDC was more prolonged than cDC, and pDC upregulated CD86 and MHC-II, but not CD80, in both the spleen and MLN. cDC were an important source of IL-12 but not TNF-, during infection, while pDC made neither of these cytokines. Instead other CD11cint cells produced these cytokines. Using five-colour flow cytometry and double intracellular cytokine staining, we detected phenotypically similar CD11cintCD11b+Gr1+ cells with distinct capacities to produce TNF-,/IL-12 or TNF-,/iNOS (inducible nitric oxide synthase) in Listeria -infected tissues. IL-12p70 was also produced by sorted CD11chi and CD11cintCD11b+Gr1+ cells. Furthermore, production of TNF-,, iNOS and IL-12 was differentially dependent on cellular localization of the bacteria. Cytosol-restricted bacteria induced TNF-, and iNOS-producing cells, albeit at lower frequency than wild-type bacteria. In contrast, IL-12 was induced only with wild-type bacteria. These data provide new insight into the relative abundance and function of distinct CD11c-expressing populations during the early stage of Listeria infection. [source] T helper 1 (Th1)/Th2 cytokine expression shift of peripheral blood CD4+ and CD8+ T cells in patients at the post-acute phase of strokeCLINICAL & EXPERIMENTAL IMMUNOLOGY, Issue 3 2008G. L. Theodorou Summary Local humoral and cellular immune responses modulate the inflammatory processes involved in the development of atherosclerotic lesions, as well as in the evolution of brain infarcts in stroke patients. The role of systemic adaptive immunity on the progression of such disease manifestations is less clear. In the current study, we evaluated the percentages of T helper 1 (Th1) [interleukin (IL)-2, interferon (IFN)-,] and Th2 (IL-4, IL-10) cytokine-producing peripheral blood CD4+ and CD8+ T cells in 23 patients with a history of ischaemic stroke (IS) at the chronic stable phase of the disease (median post-stroke time 34·5 months). Seven stroke-free individuals matched for age and vascular risk factors (matched controls, MC) were collected for comparison. To measure cytokine values at baseline and after stimulation, we used a flow cytometry method of intracellular cytokine staining. Intrinsic Th1 and Th2 cytokine production in unstimulated T cells was negligible in all study participants. Following mitogenic stimulation with phorbol 12-myristate13-acetate/ionomycin, both the IS and the MC groups exhibited a similarly strong Th1 response; IL-2 production predominated in the CD4+ T cells and IFN-, in the CD8+ T cells. However, when measuring the Th2 cytokine-production capacity post-stimulation, a significant increase in the percentage of IL-4-producing T cells was observed in the IS groups, compared with the MC group, resulting in a significantly lower ratio of IFN-,-/IL-4-producing T cells. No such Th2 enhancement could be confirmed for the case of IL-10. We propose that in IS patients there is a systemic shift of the immune system towards Th2 responses at the late post-acute phase of stroke. [source] | |||||||||||||||||||||||||