Effects of increased human tumor necrosis factor-like molecule 1A expression in peripheral blood of children with acute Guillain-Barre syndrome on interferon-gamma secretion

BACKGROUND： Human tumor necrosis factor-like molecule 1A （hTL1A） is a strong T helper cell type 1 （Thl） co-stimulator. Guillain-Barre syndrome （GBS） is an autoimmune disorder of the nervous system, which is mediated by Thl cells. OBJECTIVE： To determine hTL1A expression in peripheral blood T lymphocytes of acute GBS children and the effects of hTL1A on secretion of interferon-γ. DESIGN, TIME AND SETTING： A randomized, controlled, neuroimmunological in vitro study was performed at the Central Laboratory of First Hospital of Jilin University, China from November 2005 to November 2007. MATERIALS： Venous blood samples were obtained from 6 healthy donors, aged 6-12 years （all routine blood examination items were normal）, and 6 additional children with acute GBS, aged 6-12 years. The GBS children fell ill within 1 week and were not treated with hormones or immunoglobulin Purified recombinant human soluble tumor necrosis factor-like molecule 1A （rhsTL1A, 1 mg/mL, relative molecular mass 22 000, 6× His tag, soluble form） was supplied by the Central Laboratory of First Hospital of Jilin University, China. METHODS： Peripheral blood mononuclear cells were isolated from healthy donors using the standard Ficoll gradient centrifugation and were incubated in 96-well culture plates. The cells were assigned to the following groups： control （2 μg/mL phytohemagglutinin）, 2μg/mL phytohemagglutinin ＋ 25, 100 and 400 ng/mL rhsTL1A. T cell proliferation was quantified using the tritiated thymidine （3H-TdR） method. Serum interferon-γ levels in acute GBS children were detected by enzyme-linked immunosorbent assay （ELISA）. The ratio of hTL1A-positive T cells to CD3-positive T cells in peripheral blood of acute GBS children was determined using flow cytometry. Following in vitro pre-activation of peripheral blood mononuclear cells by 2 μg/mL phytohemagglutinin, the peripheral blood mononuclear cells were treated with 400 ng/mL exogenous rhsTLIA. Finally, peripheral blood mononuclear cell-secreted interferon-γlevels were measured by ELISA. MAIN OUTCOME MEASURES： The following parameters were measured： rhsTLIA stimulation index to stimulate proliferation of T cells; the serum interferon-γ levels in acute GBS children; the ratio of hTL1A-positive cells to CD3-positive cells; the levels of interferon-γ secreted by peripheral blood mononuclear cells in acute GBS children, as well as rhsTL1A-stimulated interferon-γ levels. RESULTS： T cell proliferation assay revealed that the stimulation index in each rhsTL1A group was greater than the control group. The stimulation index of the 400 ng/mL rhsTL1A group was the greatest. Serum interferon-γ levels in acute GBS children were significantly greater than the control group （P 〈 0.05）. The ratio of hTLIA＋ CD3＋ T cells to CD3＋ T cells in acute GBS children was significantly greater than the control group （P 〈 0.01 ）. Phytohemagglutinin stimulated peripheral blood mononuclear cells to a greater extent than 400 ng/mL rhsTL1A in the acute GBS group, and the secreted interferon-γ levels were significantly increased （P 〈 0.05）. CONCLUSION： In T cells pre-activated with 2 μg/mL phytohemagglutinin, proliferation was effectively increased with 400 ng/mL rhsTL1A treatment. Expression of hTLIA was increased in activated T cells from peripheral blood of acute GBS children, followed by increased interferon-γ secretion. These mechanisms are considered to be part of the pathological process that induces the secretion of inflammatory cytokines in GBS syndrome.

Ubiquitin Reduces Expression of Intercellular Adhesion Molecules and Tumor Necrosis Factor-α in Lung Tissue of Experimental Acute Lung Injury

Background Intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) are two important cytokines in inflammatory response, which may induce rolling and adhesion of both leukocytes and lymphocytes, while modulating vascular permeability at the same time. These adhesion molecules usually serve as surrogate markers of activation and injury of vascular endothelial cells. Tumor necrosis factor-α (TNF-α) is a key factor to induce the expression and production of the above cell adhesion molecules. However, it remains to be elucidated whether exogenous ubiquitin exerts any effect on the cytokines in sepsis-induced ALI. Methods Sixty mice were devided randomly into five groups with twelve mice in each group, i.e. CLP group, SHAM group, UB1 group (10 mg/kg), UB2 group (5 mg/kg) and UB3 group(1 mg/kg). Mice of SHAM group underwent sham operation, and other four groups underwent CLP. Six hours after surgery, mice of three UB groups received ubiquitin by caudal vein injection while CLP and SHAM group received vehicle. Seven hours after surgery, blood and lungs of all mice were collected. ICAM-1, VCAM-1 and TNF-α level of 9% lung homogenate and serum TNF-α level were measured by ELISA. Results Pulmonary ICAM-1, VCAM-1 and TNF-α level of three UB groups were lower than CLP and SHAM group, and there were several comparisons with a statistically significant difference. Serum TNF-α level of three UB groups were slightly lower than CLP group, but far higher than SHAM group. Pulmonary ICAM-1 level, VCAM-1 level and serum TNF-α level of UB3 group were lower than UB1 and UB2 group, and there was a significant difference in VCAM-1 between UB3 and UB1 group. Pulmonary TNF-α level of UB3 group was slightly higher than UB1 and UB2 group.

Claudin 1 mediates tumor necrosis factor alpha-induced cell migration in human gastric cancer cells

AIM: To investigate the role of claudin 1 in the regulation of genes involved in cell migration and tumor necrosis factor alpha (TNF-α)-induced gene expression in human gastric adenocarcinoma cells.

Elevated levels of interleukin-1β, interleukin-6, tumor necrosis factor-α and vascular endothelial growth factor in patients with knee articular cartilage injury

BACKGROUND Inflammatory cytokines play a vital role in the occurrence of osteoarticular injury and inflammation. Whether inflammation-associated factors interleukin-1β(IL- 1β), IL-6, tumor necrosis factor-α(TNF-α) and vascular endothelial growth factor (VEGF) are involved in the pathogenesis of keen articular cartilage injury remains poorly understood. AIM To measure the levels of inflammatory factors [IL-1β, IL-6, TNF-α and VEGF] in patients with knee articular cartilage injury. METHODS Fifty-five patients with knee articular cartilage injury were selected as patient groups, who were divided into three grades [mild (n = 20), moderate (n = 19) and severe (n = 16)] according to disease severity and X-ray examinations. Meanwhile, 30 healthy individuals who underwent physical examination were selected as the control group. The levels of IL-1β, IL-6, TNF-α and VEGF were measured by ELISA and immunohistochemical staining. RESULTS Compared with the control group, patient groups displayed significantly higher levels of IL-1β, IL-6, TNF-α and VEGF, and the extent of increase was directly proportional to the severity of injury (P < 0.05). In addition, the number of cells with positive staining of IL-1β, IL-6, TNF-α and VEGF in the synovial membrane were significantly increased, along with increased disease severity (P < 0.05). After treatment, the scores of visual analogue scale and the Western Ontario and McMaster University of Orthopaedic Index in patient groups were 2.26 ± 1.13 and 15.56 ± 7.12 points, respectively, which were significantly lower than those before treatment (6.98 ± 1.32 and 49.48 ± 8.96). Correlation analysis suggested that IL-1β and TNF-α were positively correlated with VEGF. CONCLUSION IL-1β, IL-6, TNF-α and VEGF levels are increased in patients with knee articular cartilage injury, and are associated with the disease severity, indicating they might play an important role in the occurrence and development of knee articular cartilage injury. Furthermore, therapeutically targeting them might be a novel approach for the treatment of keen articular cartilage injury.

Interleukin-1β,Tumor Necrosis Factor-α and Lipopolysaccharide Induce Expression of Monocyte Chemoattractant Protein-1 in Calf Aortic Smooth Muscle Cells

Summary: To investigate whether interleukin-1β(IL-1β), tumor necrosis factor-α (TNF-α) and lipopolysaccharide (LPS) induce expression of monocyte chemoattractant protein-1 (MCP-1 ) mRNA and protein in calf aortic smooth muscle cells(SMCs), calf aortic SMCs were cultured by a substrate-attached explant method. The cultured SMCs were used between the third to the fifth passage. After the cells became confluent, the SMCs were exposed to 2 ng/ml IL-1β, 20ng/ml TNF-1α and 100 ng/ml LPS respectively, and the total RNA of SMCs which were incubated for 4 h at 37℃ were extracted from the cells by using guanidinium isothiocyanate method. The expres- ion of MCP-1 mRNA in SMCs was detected by using dot blotting analysis using a probe of γ-32 P- end-labelled 35-mer oligonucleotide. After a 24-h incubation, the media conditioned by the cul- tured SMCs were collected. The MCP-1 protein content in the conditioned media was determined by using sandwich ELISA. The results were as follows: Dot blotting analysis showed that the cul- tured SMCs could express MCP-1 mRNA. After a 4-h exposure to IL-1β, TNF-α and LPS, the MCP-1 mRNA expression in SMCs was increased (3.6-fold, 2. 3-fold and 1. 6-fold, respectively). ELISA showed that the levels of MCP-1 protein in the conditioned media were also increased (2.9- fold, 1.7-fold and 1.1-fold, respectively). The results suggest that calf aortic SMCs could ex- press MCP-1 mRNA and protein. IL-1β and TNF-α can induce strong expression of MCP-1 mRNA and protein, and the former is more effective than the latter.

Evaluation of leptin,interleukin-1 beta and tumor necrosis factor alpha in serum of malaria patients as prognostic markers of treatment outcome

Objective:To analyze scrum leptin levels in patients with malaria falciparum and compare them with healthy controls and correlate with development and outcome of malaria infection.Methods:Sixty cases of malaria falciparum were included in this study as patients.Thirty healthy individuals of comparable age,racial and body mass index were taken as controls.All patients were diagnosed by clinical picture and the presence of malaria parasites in blood film.Estimation of liver function test,kidney function test,complete blood count,fasting blood sugar,fasting serum insulin,pro-inflammatory cytokine tumor necrosis factor alpha(TNFα)and interleukin 1(IL1),estimation of morning serum leptin and calculation of body mass index(kg/m^2)were done in both groups on the day of admission,on discharge and 7 d after discharge.Results:At admission,leptin levels were significantly higher in patients group than in control while lasting serum insulin levels were not significantly different between the two groups.There were significant increases as regard to TNFαand IL1 in malaria patients.Significant differences were observed between the control and the patient group for leptin,TNFαand IL1 at the time of admission and discharge.After discharge for 7 d.a significant decline in scrum leptin levels,TNFαand IL1 in the patients group was observed as compared with time of admission and time of discharge,a positive correlation between serum leptin levels and TNFαand IL1.Conclusions:Leptin hormone level might play an important role in development and outcome of malaria infection.

Increased tumor necrosis factor receptor 1 expression in human colorectal adenomas

AIM: To determine the expression statuses of tumor necrosis factor (TNF)-α, its receptors (TNF-R) and downstream effector molecules in human colorectal adenomas. METHODS: We measured the serum concentrations of TNF-α and its receptors in 62 colorectal adenoma patients and 34 healthy controls. The protein expression of TNF-α, TNF-R1, TNF-R2 and downstream signals of the TNF receptors, such as c-Jun N-terminal kinase (JNK), nuclear factor-κ B and caspase-3, were also investigated in human colorectal adenomas and in normal colorectal mucosal tissues by immunohistochemistry. Immunofluorescence confocal microscopy was used to investigate the consistency of expression of TNF-R1 and phospho-JNK (p-JNK). RESULTS: The serum levels of soluble TNF-R1 (sTNF-R1) in adenoma patients were significantly higher than in the control group (3.67 ± 0.86 ng/mL vs 1.57 ± 0.72 ng/mL, P < 0.001). Receiver operating characteristic analysis revealed the high diagnostic sensitivity of TNF-R1 measurements (AUC was 0.928) for the diagnosis of adenoma, and the best cut-off level of TNF-R1 was 2.08 ng/mL, with a sensitivity of 93.4% and a specificity of 82.4%. There were no significant differences in the serum levels of TNF-α or sTNF-R2 between the two groups. Immunohistochemistry showed high levels of TNF-R1 and p-JNK expression in the epithelial cells of adenomas. Furthermore, a high incidence of co-localization of TNF-R1 and p-JNK was identified in adenoma tissue. CONCLUSION: TNF-R1 may be a promising biomarker of colorectal adenoma, and it may also play an important role in the very early stages of colorectal carcinogenesis.

Upregulation of stromal cell-derived factor-1 alpha/CXCR4 axis-induced migration of human neural progenitors by tumor necrosis factor-alpha and interleukin-8

BACKGROUND： Studies of several animal models of central nervous system diseases have shown that neural progenitor cells （NPCs） can migrate to injured tissues. Stromal cell-derived factor 1 alpha （SDF-la）, and its primary physiological receptor CXCR4, have been shown to contribute to this process. OBJECTIVE： To investigate migration efficacy of human NPCs toward a SDF-1α gradient, and the regulatory roles of tumor necrosis factor-α （TNF-α） and interleukin-8 （IL-8） in SDF-1α/CXCR4 axis-induced migration of NPCs. DESIGN, TIME AND SETTING： An in vitro, randomized, controlled, cellular and molecular biology study was performed at the Laboratory of Department of Cell Biology, Medical College of Soochow University between October 2005 and November 2007. MATERIALS： SDF-1α and mouse anti-human CXCR4 fusion antibody were purchased from R＆D Systems, USA. TNF-αwas purchased from Biomyx Technology, USA and IL-8 was kindly provided by the Biotechnology Research Institute of Soochow University. METHODS： NPCs isolated from forebrain tissue of 9 to 10-week-old human fetuses were cultured in vitro. The cells were incubated with 0, 20, and 40 ng/mL TNF-α, or 0, 20, and 40 ng/mL IL-8, for 48 hours prior to migration assay. For antibody-blocking experiments, cells were further pretreated with 0, 20, and 40 μg/mL mouse anti-human CXCR4 fusion antibody for 2 hours. Subsequently, the transwell assay and CXCR4 blockade experiments were performed to evaluate migration of human NPCs toward a SDF-1α gradient. Serum-free culture medium without SDF-1α served as the negative control. MAIN OUTCOME MEASURES： The transwell assay was performed to evaluate migration of human NPCs toward a SDF-1α gradient, which was blocked by fusion antibody against CXCR4. In addition, CXCR4 expression in human NPCs stimulated by TNF-α and IL-8 was measured by flow cytometry. RESULTS： Results from the transwell assay demonstrated that SDF-1α was a strong chemoattractant for human NPCs （P 〈 0.01）, and 20 ng/mL produced the highest levels of migration. Anti-human CXCR4 fusion antibody significantly blocked the chemotactic effect （P 〈 0.05）. Flow cytometry results showed that treatment with TNF-α and IL-8 resulted in increased CXCR4 expression and greater chemotaxis efficiency of NPCs towards SDF-1α（P 〈 0.01）. CONCLUSION： These results demonstrated that SDF-la significantly attracted NPCs in vitro, and neutralizing anti-CXCR4 antibody could block part of this chemotactic function. TNF-α and IL-8 increased chemotaxis efficiency of NPCs towards the SDF-1αgradient by upregulating CXCR4 expression in NPCs.

Increase of tumor necrosis factor receptor 1 expression in women with unexplained early spontaneous abortion

Objective: To investigate membrane tumor necrosis factor receptor 1 protein expression level in decidua and concentration of soluble tumor necrosis factor receptor 1 in serum in women with unexplained early spontaneous abortion, threatened abortion, and compare the levels with healthy pregnant women. Methods: Thirty-seven women with unexplained early spontaneous abortion, 27 women with threatened abortion, and 34 healthy pregnant women undergoing artificial abortion of pregnancy at 6 - 10 weeks of gestation were selected. Decidual samples were collected when women were undergoing artificial abortion, and blood samples were collected at the same time. The level of membrane tumor necrosis factor receptor 1 in decidua was detected by flow cytometer, and the concentration of soluble tumor necrosis factor receptor 1 in sera was measured with an enzyme-linked immunosorbent assay. Results: The percentages of membrane tumor necrosis factor receptor 1 positive decidual cells were 16.42 ± 7.10 Mean ± SD for women with unexplained early spontaneous abortion and 13. 14 ± 6.30 for healthy pregnant women ( P < 0.05). Serum concentration of soluble tumor necrosis factor receptor 1 was significantly higher in women with unexplained early spontaneous abortion than in healthy pregnant women and in women with threatened abortion, and no difference was found between healthy pregnant women and women with threatened abortion. Conclusion: Women with unexplained early spontaneous abortion present significantly higher expression of tumor necrosis factor receptor 1 than healthy pregnant women, suggesting that over-expression of tumor necrosis factor receptor 1 may contribute to the development of early spontaneous abortion.

Tumor necrosis factor alpha receptor 1 deficiency in hepatocytes does not protect from non-alcoholic steatohepatitis, but attenuates insulin resistance in mice

BACKGROUND End-stage liver disease caused by non-alcoholic steatohepatitis(NASH)is the second leading indication for liver transplantation.To date,only moderately effective pharmacotherapies exist to treat NASH.Understanding the pathogenesis of NASH is therefore crucial for the development of new therapies.The inflammatory cytokine tumor necrosis factor alpha(TNF-α)is important for the progression of liver disease.TNF signaling via TNF receptor 1(TNFR1)has been hypothesized to be important for the development of NASH and hepatocellular carcinoma in whole-body knockout animal models.AIM To investigate the role of TNFR1 signaling in hepatocytes for steatohepatitis development in a mouse model of diet-induced NASH.METHODS NASH was induced by a western-style fast-food diet in mice deficient for TNFR1 in hepatocytes(TNFR1ΔHEP)and their wild-type littermates(TNFR1fl/fl).Glucose tolerance was assessed after 18 wk and insulin resistance after 19 wk of feeding.After 20 wk mice were assessed for features of NASH and the metabolic syndrome such as liver weight,liver steatosis,liver fibrosis and markers of liver inflammation.RESULTS Obesity,liver injury,inflammation,steatosis and fibrosis was not different between TNFR1ΔHEP and TNFR1fl/fl mice.However,Tnfr1 deficiency in hepatocytes protected against glucose intolerance and insulin resistance.CONCLUSION Our results indicate that deficiency of TNFR1 signaling in hepatocytes does not protect from diet-induced NASH.However,improved insulin resistance in this model strengthens the role of the liver in glucose homeostasis.

The interleukin-1 receptor antagonist (IL-1-Ra) and soluble tumor necrosis factor receptor I (sTNF RI) in periodontal disease

The course and severity of periodontitis can be significantly affected by bacterial virulence as well as host immunity dysfunction. Periodontal tissue destruction has been proved to result from cascade of cytokines synthesized by reactive cells upon stimulation by pathogenic bacteria and lipopolysaccharides within their cell membranes. The clinical use of genetically programmed cells, producing substances blocking IL-1, based on recombinant IL-1 antagonist, as well as cytokines activating fibroblasts and osteoblasts to regenerate the destroyed periodontal tissue could prove alternative to the conventional treatment. Another cytokine of interest in respect to periodontitis ethiopathogenesis is soluble tumor necrosis factor receptor I (sTNF RI). Observation of soluble TNF receptors as physiologic inhibitors of TNF led to its administration in therapeutic process as well as in therapy selected cases of aggressive periodontitis.

EFFECTS OF PHYTOLACCA ACINOSA POLYSACCHARIDES I ON CYTOTOXICITY OF MACROPHAGES AND ITS PRODUCTION OF TUMOR NECROSIS FACTOR AND INTERLEUKIN 1

The in vivo effects of Phytolacca acinosa poly-saccharides I (PEP-I) on immunologic cytotoxicity of mouse peritoneal macrophages and its production of tumor necrosis factor (TNF) and interleukin 1 (IL-1) were studied. PEP-I 80 or 160 mg kg was given ip twice every 4 day. Both doses were found to have significant enhancing activity on macrophages cytotoxicity against S180 sarcoma cells and malignant transformed fibroblast L929 cells. Peritoneal activated macrophages were incubated with LPS for 2 and 24 hrs to induce TNF and IL-1, respectively. The TNF and IL-1 activities were tested from cytotoxicity against L929 cells in an absorbence assay of enzymatic reaction and proliferation of thymocytes co-stimulated assay separately. The optimal time for TNF production was found on day 8. Significant increases in TNF and IL-1 were observed. In comparison of the effect of PEP-I on TNF with that of known priming agent BCG, there was no difference between them, but PEP-I had a high effect on IL-1. These results suggest that cytotoxicity of macrophages primed by PEP-I is closely related to its TNF and IL-1 production.

Effects of Irbesartan and Metformin on tumor necrosis factor receptor and monocyte chemotactic protein 1 in patients with early diabetic nephropathy

Objective: To explore the effect of Irbesartan and Metformin on tumor necrosis factor receptor 1 and monocyte chemoattractant protein-1 in patients with early diabetic nephropathy. Methods: A total of 162 patients with early diabetic nephropathy who had been admitted to the Hospital between February 2017 and February 2018 were randomly assigned into a Metformin group, an Irbesartan group, and a combination therapy group. The Metformin group were treated with oral Metformin, those in the Irbesartan group were given oral Irbesartan for treatment, and the combination therapy group was treated with Metformin combined with Irbesartan. After 3 months of continuous treatment, the levels of sTNFR1, high-sensitivity C-reactive protein, monocyte chemoattractant protein-1, glucose metabolism index, proteinuria, and serum creatinine levels in the two groups were compared. Results:After treatment, the levels of sTNFR1, sICAM-1, hs-CRP, and MCP-1 in the three groups decreased compared with those before treatment, and the levels in the combination therapy group were all shown to be lower than those of the Metformin group and the Irbesartan group, with statistically significant differences (P<0.05). The levels of glycosylated hemoglobin and fasting blood glucose in the three groups were significantly lower than before treatment, and those in the combination therapy group were lower than the Metformin group and Irbesartan group, where the difference was statistically significant (P<0.05). The 24-hour urinary protein quantification, urinary albumin excretion rate, and serum creatinine in the combination therapy group were lower than those in the Metformin group and in the Irbesartan group, where the differences were statistically significant (P<0.05). Conclusion: The effects of metformin combined with irbesartan on early diabetic nephropathy patients were significant, which can effectively reduce the levels of serum sTNFR1 and MCP-1, relieve inflammation and improve glucose metabolism and proteinuria level.

Effect of Llinagliptin on tumor necrosis factor receptor and monocyte chemoattractant protein-1 in patients with diabetic nephropathy

Objective:To explore the effect of Linagliptin on tumor necrosis factor receptor and monocyte chemoattractant protein-1 in patients with diabetic nephropathy.Methods: A total of 98 patients with diabetic nephropathy admitted to the Hospital from January 2017 to September 2018 were enrolled. The patients were divided into two groups according to the random double-blind method, with 49 cases in each group. The control group was treated with Metformin, whereas the experimental group was treated with Linagliptin plus Metformin. After 3 months of continuous treatment, the renal function [urinary albumin excretion rate, 24 h urine protein quantitation and serum creatinine], glycolipids metabolic levels [glycated hemoglobin, fasting blood glucose, total cholesterol and triglycerides], monocyte chemoattractant protein-1, tumor necrosis factor receptor, high-sensitivity C-reactive protein, and adverse reactions were compared between the two groups.Results:After 3 months of treatment, the levels of UAER, 24 h Upor and Scr in the experimental group were shown to be lower than those in the control group, and the difference was statistically significant. After 3 months of treatment, the levels of HbA1c, FPG, TC and TG in the experimental group were shown to be lower than the control group, and the difference was statistically significant. After 3 months of treatment, the levels of MCP-1, sTNFR1 and hs-CRP in the experimental group were lower than those in the control group, and the difference was statistically significant. There was no significant difference in incidence of adverse reactions between the two groups.Conclusion: For patients with diabetic nephropathy, Linagliptin is with higher safety, which can help improve their glycolipids metabolic levels and renal function, reduce the inflammatory response and the levels of MCP-1 and sTNFR1, and yet incur fewer adverse reactions.

Study of tumor necrosis factor receptor in the inflammatory bowel disease

Ulcerative colitis(UC)and Crohn’s disease(CD)are part of Inflammatory Bowel Diseases(IBD)and have pathophysiological processes such as bowel necrosis and enteric neurons and enteric glial cells.In addition,the main inflammatory mediator is related to the tumor necrosis factor-alpha(TNF-α).TNF-αis a mediator of the intestinal inflammatory processes,thus being one of the main cytokines involved in the pathogenesis of IBD,however,its levels,when measured,are present in the serum of patients with IBD.In addition,TNF-αplays an important role in promoting inflammation,such as the production of interleukins(IL),for instance IL-1βand IL-6.There are two receptors for TNF as following:The tumor necrosis factor 1 receptor(TNFR1);and the tumor necrosis factor 2 receptor(TNFR2).They are involved in the pathogenesis of IBD and their receptors have been detected in IBD and their expression is correlated with disease activity.The soluble TNF form binds to the TNFR1 receptor with,and its activation results in a signaling cascade effects such as apoptosis,cell proliferation and cytokine secretion.In contrast,the transmembrane TNF form can bind both to TNFR1 and TNFR2.Recent studies have suggested that TNF-αis one of the main pro-inflammatory cytokines involved in the pathogenesis of IBD,since TNF levels are present in the serum of both patients with UC and CD.Intravenous and subcutaneous biologics targeting TNF-αhave revolutionized the treatment of IBD,thus becoming the best available agents to induce and maintain IBD remission.The application of antibodies aimed at neutralizing TNF-αin patients with IBD that induce a satisfactory clinical response in up to 60%of patients,and also induced long-term maintenance of disease remission in most patients.It has been suggested that anti-TNF-αagents inactivate the pro-inflammatory cytokine TNF-αby direct neutralization,i.e.,resulting in suppression of inflammation.However,anti-TNF-αantibodies perform more complex functions than a simple blockade.

Tumor necrosis factor alpha increases intestinal permeability in mice with fulminant hepatic failure

AIM:To determine the effect of tumor necrosis factor alpha(TNF-α) on intestinal permeability(IP) in mice with fulminant hepatic failure(FHF),and the expression of tight junction proteins.METHODS:We selected D-lactate as an index of IP,induced FHF using D-galactosamine/lipopolysaccharide and D-galactosamine/TNF-α,assessed the results using an enzymatic-spectrophotometric method,transmission electron microscopy,immunohistochemistry,Western blotting and real-time quantitative polymerase chain reaction.The effect of the administration of antiTNF-α immunoglobulin G(IgG) antibody,before the administration of D-galactosamine/lipopolysaccharide,on TNF-α was also assessed.RESULTS:IP was significantly increased in the mouse model of FHF 6 h after injection(13.57 ± 1.70 mg/L,13.02 ± 1.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.001).Electron microscopic analysis revealed tight junction(TJ) disruptions,epithelial cell swelling,and atrophy of intestinal villi.Expression of occludin and claudin-1 mRNA was significantly decreased in both FHF models(occludin:0.57 ± 0.159 fold vs baseline,P = 0.000;claudin-1:0.3067 ± 0.1291 fold vs baseline,P = 0.003),as were the distribution density of proteins in the intestinal mucosa and the levels of occludin and claudin-1 protein(occludin:0.61 ± 0.0473 fold vs baseline,P = 0.000;claudin-1:0.6633 ± 0.0328 fold vs baseline,P = 0.000).Prophylactic treatment with antiTNF-α IgG antibody prevented changes in IP(4.50 ± 0.97 mg/L vs 3.76 ± 0.67 mg/L,P = 0.791),intestinal tissue ultrastructure,and the mRNA levels of occludin and claudin-1 expression(occludin:0.8865 ± 0.0274 fold vs baseline,P = 0.505;claudin-1:0.85 ± 0.1437 fold vs baseline,P = 0.1),and in the protein levels(occludin:0.9467 ± 0.0285 fold vs baseline,P > 0.05;claudin-1:0.9533 ± 0.0186 fold vs baseline,P = 0.148).CONCLUSION:Increased in IP stemmed from the downregulation of the TJ proteins occludin and claudin-1,and destruction of the TJ in the colon,which were induced by TNF-α in FHF mice.

Protective effect of curcumin on tumor necrosis factor-alpha-induced neuronal damage in the rat hippocampus A relationship to the inhibition of neuronal Ca^(2+) influx

BACKGROUND： Previous studies of curcumin have focused mainly on its cytotoxic properties for antitumor therapy. There are few studies addressing the application of curcumin in the prevention and treatment of nervous system diseases. OBJECTIVE： To observe the protective effect of curcumin against tumor necrosis factor-alpha （TNF-α）-induced neuronal damage in the rat hippocampus and to explore the intervention effect of curcumin on Ca^2＋ influx following neuronal damage. DESIGN, TIME AND SETTING： A cell morphological and physiological study was performed at the Institute of Brain Research, Medical College of Jinan University, China, from December 2006 to June 2007. MATERIALS： Curcumin （Sigma, USA） and TNF-α （Sigma, USA） were used in this study. METHODS： Hippocampal neurons were isolated from one-day neonatal rats and primarily cultured for 5 days. Following this they received 1 pmol/L curcumin and 100 ng/mL TNF-a pre-treatment. Dynamic morphological changes were observed for 1 hour by inverted microscopy. At 48 hours post-treatment, static morphological characteristics of the neurons were observed using inverted microscopy. Subsequently, hippocampal neurons were primarily cultured for 7 days, after receiving 1 pmol/L curcumJn and 4.5 ng/mL TNF-a pre-treatment. Intracellular free Ca^2＋ was measured using Fluo 3/acetoxymethyl ester. MAIN OUTCOME MEASURES： Effects of curcumin on TNF-a-induced neuronal damage and Ca^2＋ influx in the rat hippocampus were measured. RESULTS： Following curcumin treatment, TNF-a-induced neurons grew as normal. TNF-a induced a rapid Ca^2＋ influx into the neuronal cytoplasm; however, Ca2＋ fluorescence intensity only slightly increased when neurons were co-perfused with curcumin and TNF-α. CONCLUSION： Curcumin has a protective effect on rat hippocampal neurons possibly by reducing the TNF-α-induced rapid Ca^2＋ influx into neuronal cytoplasm and by maintaining the Ca^2＋ homeostasis.

Tumor necrosis family receptor superfamily member 9/tumor necrosis factor receptor-associated f

Hepatitis C virus(HCV)infection is an excellent immunological model for understanding the mechanisms developed by non-cytopathic viruses and tumors to evade the adaptative immune response.The antigen-specific cytotoxic T cell response is essential for keeping HCV under control,but during persistent infection,these cells become exhausted or even deleted.The exhaustion process is progressive and depends on the infection duration and level of antigenemia.During high antigenic load and long duration of infection,T cells become extremely exhausted and ultimately disappear due to apoptosis.The development of exhaustion involves the impairment of positive co-stimulation induced by regulatory cytokines,such as transforming growth factor beta 1.This cytokine downregulates tumor necrosis factor receptor(TNFR)-associated factor 1(TRAF1),the signal transducer of the T cell co-stimulatory molecule TNFR superfamily member 9(known as 4-1BB).This impairment correlates with the low reactivity of T cells and an exhaustion phenotype.Treatment with interleukin-7 in vitro restores TRAF1 expression and rescues T cell effector function.The process of TRAF1 loss and its in vitro recovery is hierarchical,and more affected by severe disease progression.In conclusion,TRAF1 dynamics on T cells define a new pathogenic model that describes some aspects of the natural history of HCV,and sheds light on novel immunotherapy strategies for chronic viral infections and cancer.