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1.
BACKGROUND: Chronic alcohol consumption polarizes the immune response away from Th1-mediated cell-mediated immunity. In the present report we investigate the first onset of alteration in immune parameters during ethanol consumption in terms of changes in splenic leukocyte cellularity and surface phenotype as well as alterations in Th1 and Th2 function. METHODS: BALB/c and C57BL/6 mice were fed ethanol-containing liquid diets, were pair-fed an isocaloric liquid control diet, or were fed solid diet and water ad libitum for up to 12 days. At intervals during the feeding period, splenic leukocytes were assessed for phenotypic markers by flow cytometry and for their ability to support antigen-induced interferon-gamma (IFNgamma) production in a coculture system. Mice were bled at intervals throughout the feeding period, and serum immunoglobin E (IgE) and alcohol levels were determined. RESULTS: Data show that phenotypic and functional alterations occur within the first few days of alcohol consumption. Both liquid diets affect splenic cellularity, and by dietary day 5, ethanol-containing liquid diets further reduce B and NK cell numbers. The decline in B cells is accompanied by a concomitant decline in the amount of major histocompatibility complex class II expressed on this population. Functional alteration in Th1-mediated IFNgamma production occurred in the population fed ethanol-containing liquid diets by dietary day 5. Th2 function, as indicated by systemic serum IgE levels in these unimmunized mice, is increased by dietary day 6 to 8 and correlated with significant blood alcohol levels. CONCLUSIONS: Ethanol consumption by mice causes a rapid decrease in splenic cellularity accompanied by a decrease in Th1 function and a rapid increase in systemic IgE levels.  相似文献   

2.
目的观察急性冠状动脉综合征(acute coronary,syndromes,ACS)患者应用阿托伐他汀后外周血中1型辅助性T细胞(Th1)和2型辅助性T细胞(Th2)的频率及其相关细胞因子的变化,探讨他汀类药物对ACS患者辅助性T细胞分化的影响。方法选择ACS患者73例,随机分为安慰剂组(36例)和阿托伐他汀组(37例),入选实验后即刻,1、3、14天抽取外周血,检测Th1和Th2频率及其相关细胞因子的浓度,其中Th1相关细胞因子为干扰素γ、白细胞介素2,Th2相关细胞因子为白细胞介素4、白细胞介素10。结果安慰剂组与阿托伐他汀组即刻外周血Th1和Th2频率及其相关细胞因子水平比较,差异无统计学意义(P0.05);阿托伐他汀组外周血1、3、14天Th1相关细胞因子干扰素γ、白细胞介素2水平较安慰剂组明显降低(P0.05),而Th2相关细胞因子白细胞介素10水平较安慰剂组明显升高(P0.05);阿托伐他汀组1、3、14天Th1频率较安慰剂组明显降低(P0.05),而Th2频率两组间差异无统计学意义(P0.05)。结论阿托伐他汀通过调节Th1和Th2亚群分化失衡,抑制炎性反应,提示他汀类药物对ACS患者有更广泛的保护作用。  相似文献   

3.
李文庭  贺永文  肖志宏 《肝脏》2009,14(1):30-32
目的研究转化生长因子β1(TGF—β1)对大鼠肝星状细胞(HSC)表达β-连环蛋白(β-catenin)的影响。方法采用逆转录聚合酶链反应(RT—PCR)比较经不同浓度的TGF-β1刺激不同时间后HSC表达β-catenin、smad3和α-SMA mRNA的变化,并比较三者之间的关系。结果1ng/ml TGF—β1刺激2h后,HSC表达β—catenin mRNA、smad3 mRNA和α—SMA mRNA量最大,β—catenin mRNA表达与两者均具有明显的相关关系(r=0.947,P〈0.01;r=0.950,P〈0.01)。结论β—catenin在TGF—β1活化HSC的过程中发挥重要作用。  相似文献   

4.
PURPOSE: Only five percent of all patients with ulcerative colitis develop primary sclerosing cholangitis. T cells accumulate at the sites of the colonic and bile duct inflammation in both ulcerative colitis and primary sclerosing cholangitis. T helper cell populations comprise functionally distinct subsets characterized by the cytokines they produce. Several alterations in cytokine production have been described in patients with ulcerative colitis. The aim of this study was to investigate possible differences in T helper subsets and cytokine production in peripheral blood and colonic mucosa among ulcerative colitis patients with and without primary sclerosing cholangitis. METHODS: Eleven patients with primary sclerosing cholangitis and extensive ulcerative colitis, 11 patients with extensive ulcerative colitis and no liver disease, and 5 patients without any history of liver disease who underwent routine colonoscopy because of previous polypectomy were included in the study. Colonoscopy with multiple biopsies was performed on all patients. Lamina propria mononuclear cells and peripheral blood mononuclear cells were isolated. A modified version of solid-phase enzyme-linked immunospot assay was used for the separate counting of cells producing interferon-, interleukin-2 (T helper 1), and interleukin-4 (T helper 2). RESULTS: No differences in spontaneous production of cytokines from peripheral blood mononuclear cells was found among the three groups. Patients with primary sclerosing cholangitis compared with patients with ulcerative colitis without liver disease showed a significant increase in the number of cells secreting interferon- after purified protein derivative stimulation (P<0.02). More cells secreting interferon- were found in the two ulcerative colitis groups than in the cell populations from healthy controls (P<0.03). The number of cells secreting interferon- in the primary sclerosing cholangitis group was significantly lower than in the ulcerative colitis group without liver disease (P<0.04). The number of cells secreting interleukin-4 was lower in the primary sclerosing cholangitis group than among the patients with ulcerative colitis only (P=0.05). CONCLUSION: Isolated lymphocytes from colonic mucosa differ in cytokine production in patients with ulcerative colitis with and without primary sclerosing cholangitis.This study was supported by grants from The Swedish Medical Research Council (7129), foundations of the Karolinska Institute, the Nanna Svartz foundation, the Swedish Society of Medicine, and the Ruth and Richard Juhlin foundation.  相似文献   

5.
In tuberculosis, Mycobacterium tuberculosis (MTB)-stimulated T-cell responses are depressed transiently, whereas antibody levels are increased. Lymphoproliferative responses of peripheral blood mononuclear cells (PBMCs) from Pakistani tuberculosis (TB) patients to both mycobacterial and candidal antigens were suppressed by approximately 50% when compared to healthy purified protein derivative (PPD)-positive household contacts. Production of interferon gamma (IFN-gamma) in response to PPD also was depressed by 78%. Stimulation with PPD and the 30-kDa alpha antigen of MTB (30-kDa antigen) induced greater secretion of transforming growth factor beta (TGF-beta), but not interleukin 10 (IL-10) or tumor necrosis factor alpha (TNF-alpha), by PBMCs from TB patients compared to healthy contacts. The degree of suppression correlated with the duration of treatment; patients treated for <1 month had significantly lower T-cell blastogenesis and IFN-gamma production and higher levels of TGF-beta than did patients treated for >1 month. Neutralizing antibody to TGF-beta normalized lymphocyte proliferation in response to PPD, partially restored blastogenesis to candidal antigen, and significantly increased PPD-stimulated production of IFN-gamma in TB patients but not in contacts. Neutralizing antibody to IL-10 augmented, but did not normalize, T-cell responses to both PPD and candida in TB patients and candidal antigen in contacts. TGF-beta, produced in response to MTB antigens, therefore plays a prominent role in down-regulating potentially protective host effector mechanisms and looms as an important mediator of immunosuppression in TB.  相似文献   

6.
Objective: Foxp3+ regulatory T cells (Tregs) play a central role in maintaining immune tolerance. Their expansion in malignant diseases leads to the suppression of host anti‐tumour responses. In this study, we evaluated the clinical significance of Tregs in patients with myelodysplastic syndrome (MDS). Patients and Methods: We analysed the number of CD4+ CD25+ Foxp3+ Tregs using three‐colour flow cytometry in the peripheral blood of 26 patients with MDS classified according to the World Health Organization classification method into four cases of refractory anaemia and refractory anaemia with ringed sideroblasts (RA/RARS), 15 cases of refractory cytopenia with multilineage dysplasia (RCMD), three cases of refractory anaemia with excess blast‐1 (RAEB‐1) and four cases of refractory anaemia with excess blast‐2 (RAEB‐2). Eighteen healthy volunteers were included as the control group. Results: The mean absolute numbers of Tregs in the RA/RARS group (0.06 × 109/L; 95% CI, 0.02–0.10 × 109/L) and RAEB group (0.06 × 109/L; 95% CI, 0.02–0.10 × 109/L) were significantly higher than that of the control group (0.03 × 109/L; 95% CI, 0.02–0.03 × 109/L) (P < 0.05). However, in the RCMD group, there was no significant difference in the mean absolute number of Tregs (0.03 × 109/L; 95% CI, 0.02–0.04 × 109/L) compared with the control group. Regarding the mean level of the CD8/Foxp3 ratio, there were significant decreases in the RA/RARS group (2.8; 95% CI, 0.7–4.9; P < 0.01), RCMD group (3.4; 95% CI, 2.0–4.4; P < 0.001) and RAEB group (2.1; 95% CI, 1.7–2.5; P < 0.001) compared with the control group (6.1; 95% CI, 5.1–7.0). Conclusions: The expansion of natural CD4+ Tregs may contribute to the suppression of CD8 through the Th1‐mediated immune response in MDS. The low CD8/Foxp3 ratio is a characteristic feature in MDS. To determine whether the expansion of CD4+ Tregs contributes to the progression of MDS subtypes into more aggressive subtypes, more MDS cases and further follow‐up are required.  相似文献   

7.
Aims/hypothesis We quantified the glomerular expression of thrombospondin-1 (THBS1, also known as TSP-1), transforming growth factor beta 1 (TGFB1, also known as TGF-β1) and connective tissue growth factor (CTGF) at each stage of diabetic nephropathy. We also examined the roles of THBS1 and CTGF in mediating high-glucose- and glycated-albumin-induced synthesis of the matrix protein, fibronectin, by mesangial cells. Methods THBS1, latent and active TGFB1, and CTGF, were detected by immunohistochemistry and in situ hybridisation in biopsies from 19 insulin-dependent diabetic patients with incipient, manifest and advanced diabetic nephropathy, and in 11 control kidneys. Findings were quantified by image analysis. Human mesangial cells were cultured with normal or high glucose, albumin or glycated albumin (Amadori product), +/−THBS1 or CTGF antisense oligonucleotides, or with peptide W, an inhibitor of TGFB1 bioactivation by THBS1. Proteins were measured by western blot analysis or ELISA. Results In glomeruli of normal kidneys, mRNA and protein levels for THBS1, latent-TGFB1 and CTGF were low. They were increased in the incipient stage of diabetic nephropathy, predominantly in mesangial areas, with further increases at later stages of the disease. Little or no active TGFB1 immunostaining was detected prior to manifest diabetic nephropathy. In contrast to high-glucose conditions, increases in fibronectin synthesis that were stimulated by glycated albumin were not dependent on THBS1 activation of latent TGFB1. However, increased fibronectin synthesis in both conditions required CTGF. Conclusions/interpretation Increased glomerular expression of all three factors occurs from the earliest stage of diabetic nephropathy. In contrast to THBS1, CTGF is required for mesangial synthesis of fibronectin stimulated by high glucose or glycated albumin, and is thus a potential therapeutic target. N. A. Wahab and L. Schaefer made an equal contribution to the work reported in this paper  相似文献   

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The effects of hematopoietic cytokines on the expression of transforming growth factors (TGF beta) mRNA and the effect of TGF beta on cytokine and on a major extracellular matrix protein, collagen I, mRNA expression was studied in human marrow stromal cells. As with other cultured mesenchymal cells, stromal cells constitutively express TGF beta 1 but not TGF alpha mRNA. In simian virus 40 (SV40)-transformed stromal cells downregulation of TGF beta 1 expression was observed 2 hours after incubation with recombinant human (rh) tumor-necrosis factor alpha (TNF alpha) and 144 h after addition of rh granulocyte macrophage colony-stimulating factor (GM-CSF). Neither interleukin-1 (IL-1)beta nor IL-6 had an observable effect on TGF beta 1 mRNA expression. TGF beta upregulated collagen I mRNA expression. These data suggest that cytokines may influence TGF beta mRNA expression.  相似文献   

10.
The pathways for differentiation of human CD4(+) T cells into functionally distinct subsets of memory cells in vivo are unknown. The identification of these subsets and pathways has clear implications for the design of vaccines and immune-targeted therapies. Here, we show that populations of apparently naive CD4(+) T cells express the chemokine receptors CXCR3 or CCR4 and demonstrate patterns of gene expression and functional responses characteristic of memory cells. The proliferation history and T cell receptor repertoire of these chemokine-receptor(+) cells suggest that they are very early memory CD4(+) T cells that have "rested down" before acquiring the phenotypes described for "central" or "effector" memory T cells. In addition, the chemokine-receptor(+) "naive" populations contain Th1 and Th2 cells, respectively, demonstrating that Th1/Th2 differentiation can occur very early in vivo in the absence of markers conventionally associated with memory cells. We localized ligands for CXCR3 and CCR4 to separate foci in T cell zones of tonsil, suggesting that the chemokine-receptor(+) subsets may be recruited and contribute to segregated, polarized microenvironments within lymphoid organs. Importantly, our data suggest that CD4(+) T cells do not differentiate according to a simple schema from naive --> CD45RO(+) noneffector/central memory --> effector/effector memory cells. Rather, developmental pathways branch early on to yield effector/memory populations that are highly heterogeneous and multifunctional and have the potential to become stable resting cells.  相似文献   

11.
目的探讨Th1/Th2、Tc1/Tc2亚群比例在慢性HBV感染的临床分型中的变化,以及在慢性HBV感染免疫病理损伤中的作用。方法用PMA、Ionomycin作为刺激剂,采用流式细胞仪(FACS)胞内细胞因子法对慢性HBV感染者外周血CD3+CD8+T细胞和CD3+CD8-T细胞内IFN~y和IL-4的表达进行分析,比较慢性肝炎、肝炎肝硬化(活动性)、慢性重症肝炎各组Th1/Th2、Tc1/Tc2亚群比例变化。结果慢性肝炎、肝炎肝硬化(活动性)、慢性重症肝炎患者的Th1、Tc1细胞均高于正常对照组。慢性重症肝炎组Th1、Tc1显著高于慢性肝炎、正常对照组(P〈0.01),慢性重症肝炎组Tc1显著高于活动性肝炎后肝硬化组(P〈0.05)。肝炎肝硬化(活动性)组Tc1显著高于正常对照组(P〈0.05)。Th1、Tc1细胞随着慢性乙型肝炎肝脏炎症活动的加剧而增高。而Th2、Tc2细胞则在各组中均无显著性差异(P〉0.05)。慢性重症肝炎患者恢复期Th1和Tc1细胞显著低于治疗前水平(P〈0.01)。结论在慢性HBV感染中,机体免疫平衡偏向Th1类反应,Th1、Tc1细胞与肝脏炎症活动严重程度呈正相关。提示Th1和Tc1细胞在慢性乙型肝炎肝脏病理发生中可能起了重要作用。  相似文献   

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13.
Background and Aim: As an important cytokine that modulate the cell cycle, the involvement of transforming growth factor beta‐1 (TGF‐β1) in carcinogenesis has been extensively studied for many years. Literatures have demonstrated that TGF‐β1 gene polymorphisms may alter the risk of various cancers, such as lung, prostate and breast. To investigate whether polymorphisms of the TGF‐β1 gene can modify the risk of gastric cancer, we conduct this hospital‐based, case‐control study. Methods: One hundred and sixty‐seven cases and 193 gender, age‐matched healthy controls were enrolled in this case‐control study. TGF‐β1 polymorphisms C‐509T and T + 869C were identified by PCR‐RFLP and ARMS‐PCR protocols, respectively. Results: Significantly different distributions of both genes were demonstrated between the case and control. Variant genotypes ?509CT, ?509TT, +869TC and +869CC were associated with increased risk of gastric cancer (P = 0.001, OR = 2.54; P = 0.016, OR = 2.09; P < 0.001, OR = 3.46; P < 0.001, OR = 4.04, respectively). With haplotype analysis, wild type CT (?509C and +869T) led to a lower frequency in case than that in control (P < 0.001), while haplotype TC was more frequent in case than in control (P < 0.001). Multiple logistic regression analysis revealed that individuals with haplotype TC had an increased likelihood of developing gastric cancer (OR = 3.19, 95%CI = 1.72–5.90). Conclusions: Our findings imply that ?509C > T and +869T > C gene polymorphisms in TGF‐β1 may be a critical risk factor of genetic susceptibility to gastric cancer in the Chinese population.  相似文献   

14.
Summary With progressive disease, the majority of patients with human immunodeficiency virus (HIV) infection develop bone marrow failure with anemia, leukopenia, and thrombocytopenia, the cause of which has not yet been clarified. Besides direct infection of bone marrow progenitor cells and immune-mediated cytolysis, the action of inhibitory cytokines, like transforming growth factor beta (TGF-) and tumor necrosis factor alpha (TNF-), has to be discussed with regard to their pathophysiological role in HIV-induced bone marrow failure. Therefore, the influence of recombinant human TGF- and TNF- on colony growth of pluripotent (CFU-GEMM), erythroid (BFU-E), and granulocyte-macrophage (CFU-GM) progenitor cells from the bone marrow of HIV-1-infected persons and normal controls was assessed in methylcellulose cultures. Both cytokines inhibited the colony formation of hematopoietic progenitor cells from HIV-positive persons. When added to unseparated bone marrow cells from HIV-infected persons and normal controls, the 50% inhibition (ID50) of BFU-E by TGF- occurred at 1.3 ng/ml and 3.7 ng/ml, respectively, while the ID50 of CFU-GM occurred at 15.5 ng/ml and 142.7 ng/ml. Concentrations of TNF-, causing 50% inhibition of colony formation by bone marrow cells from HIV-infected or noninfected individuals were 6.3 U/ml and 17.0 U/ml for BFU-E, and 24.4 U/ml and >3,000 U/ml for CFU-GM, respectively. The ID50 of the CFU-GEMM growth was below the lowest concentration of both cytokines tested. The suppressive effects were specifically abolished by antibodies against TGF- and TNF-, thus confirming that the inhibitory activities were due to the cytokine preparation used.The study was supported by a grant from theBundesgesundheitsamt  相似文献   

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Given the known role of the fas cytolytic pathway in B-cell regulation, we evaluated whether fas–fasL interactions might induce chronic lymphocytic leukaemia (CLL) cell death. De novo CLL cells expressed a low level of surface fas, and were not lysed by fasL-bearing cells. CLL cells cultured in media containing the type I cytokines interleukin (IL)-12 or interferon (IFN)-α had increased fas expression, and were readily lysed by fasL-bearing cells. In contrast, the type II cytokine IL-4 did not increase CLL cell fas, and abrogated type I cytokine-induced fas up-regulation. With prolonged culture, IL-4 exposed CLL cells expressed an intermediate level of fas; however, such CLL cells were resistant to fas-mediated lysis. These results indicate that IL-4 inhibits fas-mediated killing of CLL cells at the level of both fas receptor expression and post-receptor events. Additionally, we have defined in vitro culture conditions which generate fasL-bearing T cells from CLL patients; such T cells efficiently mediated fas-based lysis of autologous fas-positive CLL cells. We therefore conclude that type I and type II cytokines differentially regulate the fas pathway in CLL cells, and that a combination of type I cytokines and fasL-expressing T cells may represent a new approach to the immunotherapy of CLL.  相似文献   

18.
Role of gamma interferon and T cells in congenital Toxoplasma transmission   总被引:2,自引:0,他引:2  
In the BALB/c mouse model, primary infection with Toxoplasma gondii during the second third of gestation leads to a high percentage of infected foetuses. However, immunity induced by infection contracted before pregnancy prevents parasites from crossing the placenta and completely protects the foetuses, as well as the pregnant women. In order to clarify the roles of CD4+, CD8+ T lymphocytes and IFN-gamma in this protection, pregnant BALB/c mice were treated with depleting monoclonal antibodies against CD4, CD8, IFN-gamma, or control antibody. Only the foetuses of the groups treated with anti-CD8 and anti-IFN-gamma antibodies developed congenital toxoplasmosis. The maternal production of IFN-gamma was depressed in the mice depleted of CD4 and CD8 cells (P < 0.001). Determination of the blood parasite load demonstrated that materno-foetal transmission of T. gondii correlates with maternal parasitaemia. Together, these results show that CD8+ T lymphocytes and IFN-gamma play an important role in protection against congenital toxoplasmosis during reinfection.  相似文献   

19.
AIM: To investigate the effect of herbal compound 861 (Cpd861) on the transforming growth factor-β1 (TGFβ1)/ activin receptor-like kinase 1 (ALK1, type Ⅰ receptor) signaling-pathway-related gene expression in the LX-2 cell line, and the inhibitory mechanism of Cpd861 on the activation of LX-2 cells.
METHODS: LX-2 cells were treated with TGFβ1 (5 ng/mL) Cpd861 (0.1 mg/mL), TGFβ1 (5 ng/mL) plus Cpd861 (5 ng/mL) for 24 h to investigate the effect of Cpd861 on the TGFβ1/ALK1 pathway. Real-time PCR was performed to examine the expression of α-SMA (α-smooth muscle actin), ALK1, Id1 (inhibitor of differentiation 1). Western blotting was carried out to measure the levels of α-SMA and phosphorylated Smad1, and immunocytochemical analysis for the expression of α-SMA.
RESULTS: In LX-2 cells, TGFβ1/ALK1-pathway-related gene expression could be stimulated by TGFβ1, which led to excessive activation of the cells. Cpd861 decreased the activation of LX-2 cells by reducing the expression of α-SMA mRNA and protein expression. This effect was related to inhibition of the above TGFβ1/ALK1-pathway- related expression of genes such as Id1 and ALK1, and phosphorylation of Smad1 in LX-2 cells, even with TGFβ1 co-treatment for 24 h.
CONCLUSION: Cpd861 can restrain the activation of LX-2 cells by inhibiting the TGFβ1/ALK1/Smad1 pathway.  相似文献   

20.
Sézary syndrome (SzS), the leukemic form of cutaneous T-cell lymphoma, is characterized by clonal proliferation of CD4+ T cells and immune dysfunctions, raising the possibility of cytokine-related abnormalities. We previously described a decreased response to the growth-inhibitory effects of transforming growth factor type beta (TGF-beta) in SzS T cells accompanied by apparent loss of surface type II TGF-beta receptor (TGF beta RII). To specifically determine if defects exist in TGF beta RII protein expression and/or transport in SzS patients, we developed a sensitive flow cytometric method to detect TGF beta RII on the surface and intracellularly in the CD4+ T cells. Our results indicate that unlike normal CD4+ T cells, CD4+ T cells from 9 of 12 SzS patients expressed little, if any, surface TGF beta RII in response to mitogen stimulation. At the intracellular level, however, pools of TGF beta RII were comparable to those in normal CD4+ T cells. This indicates that defective trafficking of this inhibitory cytokine receptor may contribute significantly to the development of this disease.  相似文献   

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