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1.
Adhesion molecules, including ICAM-1, are an important factor in allergic inflammation caused by inhalant allergens, but there are no studies investigating their possible role in Hymenoptera venom allergy (HVA). We measured the level of ICAM-1 in 13 venom-allergic patients before and after ultra-rush venom immunotherapy (VIT). Eight patients were treated by yellow jacket venom and 5 were treated by honeybee venom. Serum ICAM-1 levels were assayed by an immunoenzymatic method, with a detection limit of 0.35 ng/ml. The mean level of ICAM-1 changed from 316.4±78.2 ng/ml before VIT to 294.7±77.9 after VIT. This difference was statistically significant (p = 0.019). These findings show that in patients with HVA there is an over-expression of ICAM-1, and that ultra-rush VIT significantly decreases ICAM-1 levels. It is likely that the known ability of VIT to correct the imbalance in T lymphocytes subpopulations and in the associated production of cytokines may account for this observation. In fact, such cytokines include IL-4 and TNF-alpha, that up-regulate adhesion molecules.  相似文献   

2.
BACKGROUND: To describe immune and endocrine responses in severe hymenoptera hypersensitivity requiring venom immunotherapy (VIT) during in vitro fertilization (IVF). CASE PRESENTATION: A 39-year old patient was referred for history of multiple miscarriage and a history of insect sting allergy. Four years earlier, she began subcutaneous injection of 100 mcg mixed vespid hymenoptera venom/venom protein every 5-6 weeks. The patient had one livebirth and three first trimester miscarriages. Allergy treatment was maintained for all pregnancies ending in miscarriage, although allergy therapy was discontinued for the pregnancy that resulted in delivery. At our institution ovulation induction incorporated venom immunotherapy (VIT) during IVF, with a reduced VIT dose when pregnancy was first identified. Serum IgE was monitored with estradiol during ovulation induction and early pregnancy. Response to controlled ovarian hyperstimulation was favorable while VIT was continued, with retrieval of 12 oocytes. Serum RAST (yellow jacket) IgE levels fluctuated in a nonlinear fashion (range 36-54%) during gonadotropin therapy and declined after hCG administration. A healthy female infant was delivered at 35 weeks gestation. The patient experienced no untoward effects from any medications during therapy. CONCLUSION: Our case confirms the safety of VIT in pregnancy, and demonstrates RAST IgE can remain <60% during IVF. With proper monitoring, VIT during IVF can be safe and appropriate for selected patients and does not appear to adversely affect blastocyst implantation, early embryo development or perinatal outcome. Further studies will be needed to develop VIT guidelines specifically applicable to IVF.  相似文献   

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To examine the role of CD28 and CTLA-4 in Th cell differentiation, we used a novel microsphere-based system to compare the effects of CD28 ligation by Ab or CD80/CD86. One set of beads was prepared by coating with anti-CD3 and anti-CD28 Ab. Another set of beads was prepared by immobilizing anti-CD3 and murine CD80-Ig fusion protein or murine CD86-Ig fusion protein on the beads. The three sets of beads were compared in their effects on the ability to activate and differentiate splenic CD4 T cells. When purified naive CD4(+) cells were stimulated in vitro, robust proliferation of similar magnitude was induced by all three sets of beads. When cytokine secretion was examined, all bead preparations induced an equivalent accumulation of IL-2. In contrast, there was a marked difference in the cytokine secretion pattern of the Th2 cytokines IL-4, IL-10, and IL-13. The B7-Ig-stimulated cultures had high concentrations of Th2 cytokines, whereas there were low or undetectable concentrations in the anti-CD28-stimulated cultures. Addition of anti-CTLA-4 Fab augmented B7-mediated IL-4 secretion. These studies demonstrate that B7 is a critical and potent stimulator of Th2 differentiation, and that anti-CD28 prevents this effect.  相似文献   

5.
Functional T-cell responses are initiated by physical interactions between T-cells and antigen-presenting cells (APCs), including dendritic cells (DCs) and B-cells. T-cells are activated more effectively by DCs than by B-cells, but little is known about the key molecular mechanisms that underpin the particular potency of DC in triggering T-cell responses. To better understand the influence of physical intercellular interactions on APC efficacy in activating T-cells, we used single cell force spectroscopy to characterize and compare the mechanical forces of interactions between DC:T-cells and B:T-cells. Following antigen stimulation, intercellular interactions of DC:T-cell conjugates were stronger than B:T-cell interactions. DCs induced higher levels of T-cell calcium mobilization and production of IL-2 and IFNγ than were elicited by B-cells, thus suggesting that tight intercellular contacts are important in providing mechanically stable environment to initiate T-cell activation. Blocking antibodies targeting surface co-stimulatory molecules CD80 or CD86 weakened intercellular interactions and dampen T-cell activation, highlighting the amplificatory roles of CD80/86 in regulating APC:T-cell interactions and T-cell functional activation. The variable strength of mechanical forces between DC:T-cells and B:T-cell interactions were not solely dependent on differential APC expression of CD80/86, since DCs were superior to B-cells in promoting strong interactions with T-cells even when CD80 and CD86 were inhibited. These data provide mechanical insights into the effects of co-stimulatory molecules in regulating APC:T-cell interactions.  相似文献   

6.
Some oligosaccharides have immunoregulatory and anti-inflammatory functions in the intestine. This study investigated the immunoregulatory effect of lactosucrose (LS) on 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitic rats. Alkaline phosphatase activity was increased but myeloperoxidase activity was decreased in the LS-TNBS group, as compared with the TNBS group (colitis rats without receiving LS). LS supplementation stimulated IL-4 and IL-10 production, while up-regulating CD86 expression in dendritic cells. LS supplementation reduced the ratio of CD80/CD86 and the ratio of IFN-γ/IL-4 compared to the TNBS group. Moreover, IFN-γ was significantly correlated with CD80 (r = 0.764, p < 0.01), whereas IL-4 was significantly correlated with CD86 (r = 0.489, p < 0.05). These results indicated that LS attenuated colitis by promoting the production of Th2-type cytokines and rebalancing the ratio of Th1/Th2 and that enhanced IL-4 production is correlated with enhanced CD86 expression in the gut. Therefore, LS is a functional food for patients with inflammatory bowel disease.  相似文献   

7.
目的:研究CD80、CD86在鼻咽癌中的表达变化及其临床病理意义。方法:选择2014年10月至2018年10月本院接诊的鼻咽癌确诊患者64例纳入研究,依据鼻咽癌复发情况分复发组(n=30)和未复发组(n=34);同期选取正常鼻粘膜活检组织33例作为正常对照组,采用SP免疫组化法检测鼻咽癌患者癌组织或正常鼻粘膜活检组织CD80、CD86蛋白的表达,并经Spearman相关性分析法分析CD80、CD86蛋白表达与鼻咽癌恶化程度的相关性。结果:鼻咽癌的癌组织CD80、CD86蛋白均呈高表达,阳性表达主要定位于细胞膜、细胞质,与肿瘤临床TNM分期、淋巴结转移均显著相关(P0.05)。复发组、未复发组肿瘤组织中的mRNA(ARD1、Ptch1、Survivin)表达显著高于对照组,且复发组高于未复发组,差异有统计学意义(P0.05)。Spearman相关性分析显示CD80、CD86蛋白表达与鼻咽癌细胞侵袭能力呈显著正相关(r=0.403、0.547,P0.05)。结论:鼻咽癌的癌组织内CD80、CD86蛋白均呈高表达,与鼻咽癌的临床分期、淋巴结转移及放疗预后关系密切,可能作鼻咽癌临床诊治及预后评估的重要参考指标。  相似文献   

8.
The CD28 costimulatory pathway is critical to T cell activation. Blockade of the interaction of CD28 with its ligands CD80 and CD86 using CTLA4-Ig has been proposed as a therapy for a number of immune-based disorders. We have used a murine model of influenza virus infection to study the role of CD28-dependent costimulation in the development of antiviral immune responses. In vivo treatment with CTLA4-Ig to block the interaction of CD28 with CD80 and CD86 reduced virus-specific cytotoxicity and IFN-gamma production by bronchoalveolar lavage fluid CD8+ T lymphocytes in vitro. It also resulted in decreased numbers of virus-specific CD8+ T lymphocytes in the bronchoalveolar lavage fluid, lung, and spleen and lowered virus-specific Ab titers. Mice treated with CTLA4-Ig were able to control and clear the virus infection, but this was delayed compared with controls. Treatment with Y100F-Ig, a mutant form of CTLA4-Ig which selectively binds to CD80 and blocks the CD28-CD80 interaction leaving CD28-CD86 binding intact, did not affect Ab production, spleen cytotoxic precursors, or clearance of virus. However, Y100F-Ig treatment had a clear effect on lung effector cell function. Secretion of IFN-gamma by bronchoalveolar lavage fluid CD8+ T lymphocytes in vitro was decreased, and the number of virus-specific CD8+ T lymphocytes in the bronchoalveolar lavage fluid and lungs of infected mice was reduced. These results indicate that CD28-dependent costimulation is important in the antiviral immune response to an influenza virus infection. The individual CD28 ligand, CD80, is important for some lung immune responses and cannot always be compensated for by CD86.  相似文献   

9.
Regulatory T cells (Treg) are important in maintaining tolerance to self tissues. As both CD28 and CTLA-4 molecules are implicated in the function of Treg, we investigated the ability of their two natural ligands, CD80 and CD86, to influence the Treg-suppressive capacity. During T cell responses to alloantigens expressed on dendritic cells, we observed that Abs against CD86 potently enhanced suppression by CD4(+)CD25(+) Treg. In contrast, blocking CD80 enhanced proliferative responses by impairing Treg suppression. Intriguingly, the relative expression levels of CD80 and CD86 on dendritic cells are modulated during progression from an immature to a mature state, and this correlates with the ability of Treg to suppress responses. Our data show that CD80 and CD86 have opposing functions through CD28 and CTLA-4 on Treg, an observation that has significant implications for manipulation of immune responses and tolerance in vivo.  相似文献   

10.
Activated human blood γδ T cells have also been previously demonstrated to behave as professional APCs, although the processes that control APC function have not been characterized. n this study, we show that the acquisition of potent APC function by human blood γδ T cells is achieved after physical interaction with an Ab-coated target cell, a process that we refer to as licensing. In cancer models, licensing of γδ T cells by tumor-reactive mAbs promotes the uptake of tumor Ags and professional presentation to tumor-reactive αβ T cells. We propose that licensing by Ab is a mechanism whereby the adaptive properties of γδ T cells are induced by their innate functions in a spatially and temporally controlled manner.  相似文献   

11.
CD80 and CD86 interact with CD28 and deliver costimulatory signals required for T cell activation. We demonstrate that ex vivo allergen stimulation of bronchial biopsy tissue from mild atopic asthmatic, but not atopic nonasthmatic, subjects induced production of IL-5, IL-4, and IL-13. Explants from both study groups did not produce IFN-gamma, but secreted the chemokine RANTES without any overt stimulation. In addition to allergen, stimulation of asthmatic explants with mAbs to CD3 and TCR-alphabeta but not TCR-gammadelta induced IL-5 secretion. Allergen-induced IL-5 and IL-13 production by the asthmatic tissue was inhibited by anti-CD80 and, to a lesser extent, by anti-CD86 mAbs. In contrast, the production of these cytokines by PBMCs was not affected by mAbs to CD80, was inhibited by anti-CD86, and was strongly attenuated in the presence of both Abs. FACS analysis revealed that stimulated asthmatic bronchial tissue was comprised of CD4+ T cells that expressed surface CD28 (75. 3%) but little CTLA-4 (4.0%). Neutralizing mAbs to CD40 ligand had no effect on the cytokine levels produced by asthmatic tissue or PBMCs. Collectively, these findings suggest that allergen-specific alphabeta T cells are resident in asthmatic bronchial tissue and demonstrate that costimulation by both CD80 and CD86 is essential for allergen-induced cytokine production. In contrast, CD86 appears to be the principal costimulatory molecule required in PBMC responses. Attenuation of type 2 alphabeta T cell responses in the bronchial mucosa by blocking these costimulatory molecules may be of therapeutic potential in asthma.  相似文献   

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13.
The interactions between CD80 and CD86 on antigen-presenting cells and CD28 on T cells serve as an important costimulatory signal in the activation of T cells. Although the simplistic two-signal hypothesis has been challenged in recent years by the identification of different costimulators, this classical pathway has been shown to significantly impact antiviral humoral and cellular immune responses. How the CD80/CD86-CD28 pathway affects the control of chronic or latent infections has been less well characterized. In this study, we investigated its role in antiviral immune responses against murine gammaherpesvirus 68 (MHV-68) and immune surveillance using CD80/CD86(-/-) mice. In the absence of CD80/CD86, primary antiviral CD8(+) T-cell responses and the induction of neutralizing antibodies were severely impaired. During long-term immune surveillance, the virus-specific CD8(+) T cells were impaired in IFN-gamma production and secondary expansion and exhibited an altered phenotype. Surprisingly, a low level of viral reactivation in the lung was observed, and this effect was independent of CD28 and CTLA-4. Thus, CD80 and CD86, signaling through CD28 and possibly another unidentified receptor, are required for optimal immune surveillance and antiviral immune responses to murine gammaherpesvirus.  相似文献   

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Although previous studies have shown that altered B7 costimulation plays a critical role in UV irradiation-induced regulation of immunity, the individual roles of the B7 receptors (CD28 and CTLA-4) or the B7 family members (CD80 and CD86) have not been explored. Thus, we investigated CTLA-4 signaling during photocarcinogenesis of chronically UV-B-exposed mice using an antagonistic anti-CTLA-4 Ab. Anti-CTLA-4-treated mice developed significantly fewer UV-induced tumors. Moreover, anti-CTLA-4 treatment induced long-lasting protective immunity because progressively growing UV tumors inoculated into anti-CTLA-4- and UV-treated mice that had not developed tumors were rejected. Next, we used mice deficient for CD80, CD86, or both in photocarcinogenesis studies to assess the relative contributions of these CTLA-4 ligands. Double-deficient mice showed significantly reduced UV-induced skin tumor development, whereas CD86(-/-) mice produced skin cancer earlier compared with CD80(-/-) and control mice. The growth of UV-induced tumors appears to be controlled by UV-induced suppressor T cells, because CD80(-/-)/CD86(-/-) mice had strongly reduced numbers of UV-induced CD4(+)CD25(+) suppressor T cells. In vitro, CTLA-4 blockade inhibited the suppressor activity of UV-induced CD4(+)CD25(+) T cells, suggesting that reduced photocarcinogenesis might be due to decreased numbers or function of suppressor T cells. Together, these data indicate that blocking CD80/86-CTLA-4 signaling induced immune protection against the development of UV-induced skin tumors. Furthermore, CD86-mediated costimulation appears to play a more critical role in the protection against photocarcinogenesis than CD80.  相似文献   

16.
THE purpose of this study was to investigate the effects of Tityus serrulatus venom (TSV) on murine peritoneal macrophages evaluated in terms of activation. The effects of crude TSV were analysed by detection of cytokines, oxygen intermediate metabolites (H2O2) and nitric oxide (NO) in supernatants of peritoneal macrophages. Several functional bioassays were employed including an in vitro model for envenomating: cytotoxicity of TSV was assessed using the lyses percentage. Tumor necrosis factor (TNF) activity was assayed by measuring its cytotoxic activity on L-929 cells, and interleukin-6 (IL-6) and interferon-gamma (IFN-gamma) were assayed by enzyme-linked immunosorbent assay, whereas NO levels were detected by Griess colorimetric reactions in culture supernatant of macrophages incubated with TSV and subsequently exposed to either lipopolysaccharide or IFN-gamma. Incubation of macrophages with TSV increased production of IL-6 and IFN-gamma in a dose-dependent manner. TNF production was not detected in supernatants treated with TSV at any concentration. The increase in IL-6 secretion was not associated with concentration-dependent cytoxicity of TSV on these cells. These data suggest that the cytotoxicity does not appear to be the main cause of an increased cytokine production by these cells. Although NO is an important effector molecule in macrophage microbicidal activity, the inducing potential of the test compounds for its release was found to be very moderate, ranging from 125 to 800 mM. Interestingly, NO levels of peritoneal macrophages were increased after IFN-gamma. Moreover, NO production had an apparent effect on macrophage activity. The results obtained here also shown that the TSV induces an important elevation in H2O2 release. These results combined with NO production suggest that TSV possesses significant immunomodulatory activities capable of stimulating immune functions in vitro.  相似文献   

17.
Beta-arrestin 2 has been shown to participate in the pathogenesis of asthma by inducing Th2 cell migration to the lungs. Whether beta-arrestin 2 regulates cytokine production of CD4+ T cells is still unknown. The aim of the present study was to investigate the effect of beta-arrestin 2 on the cytokine production of CD4+ T lymphocytes and the mechanism involved in a mouse model for asthma. After silencing beta-arrestin 2 expression in CD4+ T lymphocytes from asthmatic mice by RNA interference (RNAi), the interleukin-4 (IL-4) and interferon-gamma (IFN-gamma) levels in CD4+ T lymphocyte culture supernatants with or without terbutaline stimulation were determined. Cell-surface beta2 adrenergic receptor (beta2AR) as well as GATA3 expression of CD4+ T lymphocytes were also measured. CD4+ T lymphocytes of mice with allergic asthma expressed higher levels of beta-arrestin 2 on both mRNA and protein levels. beta-arrestin 2 RNAi decreased IL-4 (43.16%) and GATA3 (protein 77.21%, mRNA 62.98%) expression after terbutaline stimulation. Cell-surface beta2AR of CD4+ T lymphocytes decreased (15.27%) after terbutaline treatment, but recovered after beta-arrestin 2 RNAi down-modulation. These findings demonstrate that beta-arrestin 2 regulates IL-4 production and GATA3 expression of CD4+ T lymphocytes partly through the beta2AR signaling pathway in an allergic asthma model.  相似文献   

18.
利用肝再生增强因子(augmenter of liver regeneration, ALR)的siRNA阻断人肝癌细胞株HepG2表达ALR,观察HepG2细胞MHCI、DR、CD80、CD86的表达是否受影响,以探讨ALR是否通过影响MHCI、DR、CD80、CD86表达参与肝癌细胞逃避机体的免疫监视.培养HepG2,分为未转染组、转染阳性SiRNA组、转染阴性SiRNA组、转染脂质体空质粒组; RT-PCR检测转染前后hALR mRNA的表达, RT-PCR、Western blot印迹法、流式细胞术(FCM)检测HepG2细胞表达MHCI、DR、CD80、CD86的水平.结果表明,转染阳性SiRNA组hALR mRNA 的表达较转染阴性SiRNA组明显下降,转染阳性SiRNA组和转染阴性SiRNA组MHCI、DR、CD80、CD86的表达均无差异;脂质体转染组除CD80 mRNA外,MHCI、DR、CD86 mRNA表达均较未转染组增高;脂质体转染组MHCI、DR、CD80、CD86的表达水平均较未转染组有上升趋势.因此,阳性SiRNA具有显著和特异性抑制hALR表达的作用,阻断ALR的表达不影响HepG2细胞表达MHCI、DR、CD80、CD86,ALR不通过影响MHCI、DR、CD80、CD86的表达参与肝癌细胞逃避机体免疫监视.转染载体可能影响某些基因的表达.  相似文献   

19.
The Nef protein of HIV-1 mediates immune evasion by relocating major histocompatibility complex (MHC) molecules and the immune costimulatory molecules CD80 and CD86 away from the monocytic cell surface. We describe a two-pronged mechanism by which Nef removes CD80 and CD86 from the cell surface. While MHCI, CD80, and CD86 are all internalized via a dynamin-independent pathway, the endocytic mechanism used for costimulatory molecules is distinct from MHCI relocation. Nef expression results in the activation and actin-dependent translocation of Src kinase to the cell periphery. At the cell surface, Src promotes Rac activation via TIAM, a guanine nucleotide exchange factor for Rac. Nef also binds to the cytosolic tails of CD80 and CD86, triggering their endocytosis via Rac-based actin polymerization. These data reveal the use of an unusual molecular mechanism triggered in the host cell by HIV to affect its viral immune evasion strategy and suggest approaches for its subversion.  相似文献   

20.
为了探讨肺内调节肽对人支气管上皮细胞(human bronchial epithelial cells,HBECs)人类白细胞抗原DR(human leukocyte antigen DR,HLA—DR)、CD80和CD86表达的影响,采用免疫细胞化学技术和流式细胞术检测HBECs在非应激和臭氧应激两种状态下HLA-DR、CD80、CD86的表达。结果显示,HBECs表达HLA—DR,臭氧应激状态下HBECs HLA-DR表达降低(P〈0.05);VIP、P3513和CGRP使非应激和臭氧应激两种状态下的HBECs HLA—DR表达增高(均P〈0.05)。HBECs表达协同刺激分子CD80,臭氧应激状态下CD80表达降低(P〈0.05),VIP对非应激的HBECs的CD80表达无影响,使臭氧应激状态下CD80表达增高(P〈0.05);CGRP使非应激状态下的HBECs的CD80表达降低(P〈0.05),使臭氧应激状态下CD80表达增高(P〈0.05);P3513使非应激状态下CD80表达增高(P〈0.05),可使臭氧应激状态下CD80表达降低(P〈0.05)。在HBECs没有检测到CD86表达,臭氧攻击也不能刺激其表达。上述结果提示,HBECs具备成为抗原递呈细胞的必要条件,肺内调节肽可通过调节HLA—DR和协同刺激分子的表达调节HBECs的抗原递呈作用。  相似文献   

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