首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Potent stimuli for CD 4+ T cell differentiation are cytokines. Among them, IL-12 or IL-4 induce naive CD 4+ T cells to Th 1 or Th 2 cells, respectively. In this study we found that macrophage-tropic (M-tropic) HIV-1 strains more efficiently replicated in interleukin 12 (IL-12) induced T helper 1 (Th 1)-type culture derived from normal CD 4+ T cells than T-cell-line-tropic (T-tropic) strains did. In contrast, T-tropic strains preferentially infected IL-4 induced Th 2-type culture derived from same donor CD 4+ T cells. Additional studies using chimeric viruses demonstrated that the V 3 region of gp 120 was the principle determinant for this efficient replication. It was also isolated T-tropic viruses from an acutely infected patient who had been evidenced as severe CD 4 depletion during short time course. These results indicate that HIV-1 isolates exhibit differences in the ability to infect CD 4+ T cell subset such as Th 1 or Th 2 cells, and that this difference may partly correlate with the viral pathogenesis. The findings suggest that immunological condition is one of the factors responsible for inducing selection of HIV-1 strains.  相似文献   

2.
Human recombinant alpha interferon, A/D, significantly reduced the replication and cell fusion induced by herpes simplex virus type 1 in monkey cells. Thin-section electron microscopy of interferon-treated monkey cells showed distinct assembly of nucleocapsids within the nucleus. Analysis of virus-specific proteins by the immunoblot technique confirmed that A/D interferon had no significant effect on the expression of major nucleocapsid proteins, although the expression of glycoproteins B and D was reduced in interferon-treated cells. The possibility of an interferon-induced block at a late stage in virus morphogenesis is discussed.  相似文献   

3.
Decreased glutamine concentrations are found in patients with catabolic stress and are related to susceptibility to infections. In this study, we evaluated the role of glutamine in Th1/Th2 cytokine responses. Peripheral blood mononuclear cells were stimulated with phytohemagglutinin (PHA), live attenuated bacillus Calmette-Guérin (BCG), or measles virus in the presence of different glutamine concentrations. We found that glutamine at an optimal concentration (0.6 mM) significantly enhanced PHA-stimulated lymphocyte proliferation as well as Th1 [interferon-gamma (IFN-gamma) and interleukin-2 (IL-2)] and Th2 cytokine (IL-4 and IL-10) production. In the absence of glutamine, BCG and measles virus elicited minimal lymphocyte proliferation, whereas BCG enhanced Th1 cytokine response and measles virus promoted Th2 cytokine response. Interestingly, addition of glutamine promoted the BCG-elicited Th1 cytokine response (IFN-gamma), but suppressed the measles-induced Th2 cytokine response (IL-10). These results suggest that appropriate glutamine levels may influence host responses to different antigens and microorganisms. Furthermore, predominately Th1, but not Th2, cytokine responses required the presence of optimal concentrations of glutamine.  相似文献   

4.
The thiol antioxidant N-acetyl- L-cysteine (NAC), known as a precursor of glutathione (GSH), is used in AIDS treatment trials, as a chemoprotectant in cancer chemotherapy and in treatment of chronic bronchitis. In vitro, GSH and NAC are known to enhance T cell proliferation, production of IL-2 and up-regulation of the IL-2 receptor. The 120-kD CD30 surface antigen belongs to the tumour necrosis factor (TNF) receptor superfamily. It is expressed by activated T helper (Th) cells and its expression is sustained in Th2 cells. We have analysed the effect of GSH and NAC on the cytokine profile and CD30 expression on human allergen-specific T cell clones (TCC). TCC were stimulated with anti-CD3 antibodies in the presence of different concentrations of GSH and NAC. Both thiols caused a dose dependent down-regulation of IL-4, IL-5 and IFN-gamma levels in Th0 and Th2 clones, with the most pronounced decrease of IL-4. Furthermore, they down-regulated the surface expression of CD30, and the levels of soluble CD30 (sCD30) in the culture supernatants were decreased. In contrast, the surface expression of CD28 or CD40 ligand (CD40L) was not significantly changed after treatment with 20 m M NAC. These results indicate that GSH and NAC favour a Th1 response by a preferential down-regulation of IL-4. In addition, the expression of CD30 was down regulated by GSH and NAC, suggesting that CD30 expression is dependent on IL-4, or modified by NAC. In the likely event that CD30 and its soluble counterpart prove to contribute to the pathogenesis in Th2 related diseases such as allergy, NAC may be considered as a future therapeutic agent in the treatment of these diseases.  相似文献   

5.
The effect of zinc, nickel, cobalt and cadmium complexes of acyclovir (ACV) and its omicron-acetylated derivative (Ac-ACV) on the replication of wild type (wt) and ACV-resistant (ACV(R)) strains of Herpes simplex virus 1 (HSV-1) and Herpes simplex virus 2 (HSV-2) was examined. According to cytotoxicity, these compounds followed the order Ni-ACV chloride > Cd-ACV 3 Ni-ACV nitrate > ACV = Zn-ACV nitrate = Ac-ACV = Zn-Ac-ACV > Zn-ACV chloride > Co-ACV. Besides Ac-ACV, the only active complexes in inhibiting virus replication were Zn-ACV nitrate and Zn-Ac-ACV, which effectively suppressed the growth of both wt and ACVR strains of HSV-1 and HSV-2. The most active and most selective inhibitor of the growth of ACVR strains of HSV-1 and HSV-2 was Ac-ACV; its EC50 and SI were 100 and 10 times higher than those of ACV, respectively. Zn-Ac-ACV was less active than Ac-ACV, obviously due to the stability of the complex. Zn-ACV nitrate was active against both wt and ACVR strains of HSV-1; its activity and selectivity were 100 and 75 times higher than those of ACV, respectively. Ac-ACV and Zn-Ac-ACV suppressed the pre-mitotic arrest caused by HSV-1 infection during the first 2 hrs of infection and later on restored the cell division.  相似文献   

6.
熊果酸对正常人外周血淋巴细胞Th1型细胞因子的影响   总被引:2,自引:0,他引:2  
本实验旨在研究熊果酸对正常人外周血淋巴细胞Th1型细胞因子的影响,并对机制作初步探讨。采用半定量RT-PCR和夹心法ELISA分别检测不同浓度熊果酸对PHA和PMA活化的外周血淋巴细胞的Th1型细胞因子(IFN-γ和IL-2)mRNA的表达及分泌的影响。结果显示Th1型细胞因子mRNA和蛋白的表达水平均随熊果酸浓度的增加而下降(P<0.05),表明熊果酸可能对IFN-γ和IL-2在转录和(或)转录后水平发挥抑制作用,有可能用于自身免疫性疾病和超敏反应性疾病的防治。而熊果酸和地塞米松分子结构相似,可能通过类似机制下调糖皮质激素受体发挥作用。  相似文献   

7.
OBJECTIVES: We examined the effect and time of addition of beta-chemokines on human immunodeficiency virus type 1 (HIV-1) replication, binding, and uncoating in human macrophages and measured CCR5 receptor expression during virus binding and uncoating. METHODS: Macrophages were treated with beta-chemokines before infection, at infection, or postinfection, and virus replication was determined by p24 antigen level. Binding and uncoating of 35[S]-methionine-labeled HIV-1 was measured. CCR5 expression was determined by flow cytometry. RESULTS: The beta-chemokines potently inhibited virus replication. The strongest inhibition occurred when cultures were pretreated and maintained with beta-chemokines. Beta-chemokines also caused strong inhibition of viral uncoating and a considerable decrease in CCR5 expression during uncoating. CONCLUSIONS: CCR5 receptors appear to be internalized and recycled to the cell surfaces during HIV entry. The down-regulation of CCR5 expression by beta-chemokines during virus uncoating probably accounts for the reduction in virus uncoating (entry) and hence in virus replication.  相似文献   

8.
目的通过测定早产儿血浆中还原型谷胱甘肽(GSH)含量,评价早产儿体内的抗氧化能力.方法将20例临床及X线表现排除RDS的早产儿及10例正常足月儿,分别于0d、3d采静脉血2ml ,测定两组新生儿外周血浆中GSH的含量,比较两组婴儿之间及早产儿0d 、3d 时GSH含量.结果早产儿出生时GSH含量明显低于足月儿(P<0.01),且早产儿3d时GSH含量较0d时明显降低,差异显著(P<0.05).结论早产出生总是伴有GSH水平低下,且生后2-3d 达到最低值,这将影响其肺脏的抗氧化防御能力.因此,早产儿生后需及时补充GSH.  相似文献   

9.
Mapping of a major antioxidant, glutathione (GSH), was achieved in the human brain in vivo using a doubly‐selective multiple quantum filtering based chemical shift imaging (CSI) of GSH at 3 T. Both in vivo and phantom tests in CSI and single voxel measurements were consistent with excellent suppression of overlapping signals from creatine, γ‐Amino butyric acid (GABA) and macromolecules. GSH concentration in the fronto‐parietal region was 1.20 ± 0.16 µmol/g (mean ± SD, n = 7). The longitudinal relaxation time (T1) of GSH in the human brain was 397 ± 44 ms (mean ± SD, n = 5), which was substantially shorter than that of other metabolites. This GSH‐CSI method permits us to address regional differences of GSH in the human brain under conditions where oxidative stress has been implicated, including multiple sclerosis, aging and neurodegenerative diseases. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

10.
11.
Recent evidence from mouse models indicates that neonatal exposure to lipopolysaccharide (LPS) can prevent experimentally induced allergic disease. Furthermore, we noted that human cord blood mononuclear cells (CBMC) have an increased proliferative response to LPS relative to their respective maternal peripheral blood mononuclear cells (PBMC). We sought, therefore, to examine the cytokine expression profile induced by LPS in CBMC and its relationship to the LPS-mediated proliferative response. CBMC and maternal PBMC were evaluated for IL-10, IL-4, IL-13, IL-12 alpha, and IFN-gamma expression after LPS stimulation by real-time PCR. IFN-gamma secretion was detected by enzyme-linked immunosorbent assay. LPS increased IFN-gamma and IL-13, but decreased IL-4 expression in CBMC (P < 0.024, P < 0.014, and P < 0.027, respectively). In PBMC, however, no significant changes in expression were noted after LPS stimulation. Stimulation by LPS significantly increased the secretion of IFN-gamma in CBMC compared with PBMC at the two concentrations analyzed (1 ng/ml, P < 0.048; 10,000 ng/ml, P < 0.003). The magnitude of the LPS-mediated proliferative effect in CBMC directly correlated to the level of induction of IFN-gamma (P < 0.01), but inversely correlated to the induced levels of IL-4 and IL-13 (P < 0.01 and P = 0.01, respectively). No association of the CBMC proliferative response to IL-12 alpha or IL-10 was noted. Thus, a high proliferative response to LPS in CBMC correlates with a change from a Th2- to Th1-induced cytokine expression profile. Since early exposure to LPS may protect against allergic disease, one may speculate that an aberrant response to LPS may increase the likelihood of developing overt disease in susceptible individuals.  相似文献   

12.
Mercuric chloride (HgCl2) has contrasting effects on different rat strains: susceptible strains, e.g. Brown Norway (BN) develop polyclonal B cell activation, multiple autoantibodies and widespread tissue injury. Lewis (LEW) rats are resistant: no autoimmune response occurs after HgCl2; instead, there is immunosuppression. We have previously shown, by fully quantitative polymerase chain reaction (PCR), up-regulation of interleukin-4 (IL-4) gene expression in HgCl2-treated BN rats, implicating Th2 cells in the autoimmune syndrome. Involvement of the reciprocal Th1 subset, producing interferon-γ (IFN-γ), in resistance of LEW rats to HgCl2 has been suggested. We now report extensive analysis of Th1 and Th2 cytokine gene expression in spleen and lymph nodes of susceptible (BN) and resistant (LEW) rats after HgCl2. IL-4 and IFN-γ were analyzed by quantitative PCR, other cytokines were assessed using semiquantitative PCR: the relative merits of these two techniques are discussed. We show pronounced up-regulation of IL-4 and more modest up-regulation of IFN-γ in BN rats, but no up-regulation of either in LEW rats. Baseline levels of IFN-γ were higher in LEW rats. Semi-quantitative PCR showed increased expression of IL-2, IL-6 and IL-10 in BN; in LEW rats only IL-10 was increased. There was no marked change in IL-5, IL-13 or transforming growth factor-β (TGF-β) in either strain. These data further support the key role of IL-4 in HgCl2-induced autoimmunity, and suggest that failure of up-regulation of IL-4, together with higher baseline IFN-γ expression, accounts for resistance of LEW rats to HgCl2. However, neither IFN-γ nor TGF-β can be implicated in HgCl2-induced immunosuppression in the LEW rat in vivo: our data suggest a role for IL-10 in this phenomenon.  相似文献   

13.
In order to identify cellular genes which interfere with HIV-1 replication in monocyte-derived macrophages (MAC), cells were stimulated with interferon (IFN) or lipopolysaccharide (LPS) leading to a pronounced inhibition of HIV-1 infection in these cells, and the resulting gene expression was analyzed. Using the microarray technology we identified a gene named Stimulated Trans-Acting Factor of 50 kDa (Staf50), which is known to repress the activity of the HIV-1 LTR. Analysis of the Staf50 expression by real-time PCR showed an overexpression in IFNalpha (up to 20-fold) and LPS (up to 10-fold)-stimulated MAC as well as in infected cells (up to 3-fold). For stable overexpression, 293 T cells and primary macrophages were transduced with Staf50-IRES-GFP bicistronic pseudotype viruses. After transduction, 293 T CD4/CCR5 and MAC were infected with HIV-1, and virus replication was monitored by p24 ELISA. Overexpression of Staf50 inhibited the HIV-1 infection between 50% and 90% in 293 T CD4/CCR5 as well as in MAC. Our findings suggest that host genetic effects in combination with viral properties determine the susceptibility of an appropriate target cell for HIV-1 infection as well as the replication potential of the virus in the cell resulting in an overall productive infection.  相似文献   

14.
目的:通过研究喘可治注射液对人外周血单个核细胞(PBMCs)Th1/Th2细胞因子谱的影响,探讨喘可治注射液的免疫调节作用机制。方法:以流式微球分析(CBA)法检测不同处理情况下,人外周血单个核细胞分泌Th1(IFN-γTNF-α、IL-2)和Th2(IL4、IL-6、IL-10)细胞因子水平。结果:健康人PBMCs体外培养12小时后,上清中细胞因子主要为TNF-α和IL-6,喘可治使Th1和Th2细胞因子全面升高;喘可治对PDB加离子霉素诱导的PBMCs分泌Th1和Th2细胞因子具有抑制作用,并能抑制流感病人异常升高的INF-γ、TNF-α、IL-6和IL-10分泌。结论:喘可治注射液上调健康人PBMCs分泌TH1和Th2细胞因子,对异常活化的PBMCs分泌的Th1和Th2细胞因子则具有下调作用。  相似文献   

15.
目的 探讨细胞因子在新型甲型H1N1流感重症患者不同临床预后中作用。方法 2009年4月至2010年1月间北京佑安医院收治甲型H1N1流感重症患者28例(16例治疗痊愈,12例死亡)为研究对象,正常对照11例。Luminex技术检测血清中Th1/Th2细胞因子水平。结果 Th1类细胞因子中IL-2,IL-12 (P70),IFN-γ水平在死亡组明显低于治愈组及正常组,差异有统计学意义,P值均< 0.05。Th2类细胞因子中IL-4水平在死亡组明显低于治愈组及正常组,P=0.0012,0.031。结论 新型H1N1感染重症治愈患者、死亡患者Th1类细胞因子水平均呈下降趋势,死亡组患者下降更为明显,Th1类细胞因子水平的严重减低可能与重症患者预后不良相关。  相似文献   

16.

Objective

In vitro cell culture models are widely used in inflammation research; however, information regarding the time- and dose-dependency of inflammatory responses toward LPS in these cell lines is scattered in the literature.

Material

J774A.1 mouse macrophage and THP-1 human monocyte cell lines.

Treatment

J774A.1 and THP-1 cells were treated with 0–500?ng/mL lipopolysaccharide for 0–24?h.

Methods

SRB and BCA tests were used to measure total protein. Real-time PCR was used to determine gene expression levels, and ELISA was used to assess the protein levels. One-way ANOVA and Tukey’s Honestly Significant Difference test were used to test the significance levels.

Results

In J774A.1 and THP-1 cells, cytokines responded in distinct patterns upon LPS stimulation in a time- and dose-dependent manner, and the differential regulation of the response to LPS between J774A.1 and THP-1 cells appeared to correlate with the differential regulation of TLR4 at the mRNA level.

Conclusion

In summary, this study indicated that temporal and dose-dependent responses to LPS need to be controlled for and that extrapolation of data on mechanisms may differ between cell lines of different origin.  相似文献   

17.
BACKGROUND: Human bocavirus (hBoV) is regarded as one of the possible etiologic agents in lower respiratory tract infection and bronchial asthma exacerbation in children despite frequent co-detection with other respiratory viruses. The immunologic response in children with hBoV infection is still not clear. OBJECTIVES: To investigate the profiles of T helper-1 (Th1)/T helper-2 (Th2) cytokines in children with hBoV-associated bronchiolitis. STUDY DESIGN: This study utilized of 59 nasopharyngeal aspirates from 59 infants aged 24 months or younger, including 29 from children with hBoV-related bronchiolitis and 30 with respiratory syncytial virus (RSV)-related bronchiolitis. Eighteen infants hospitalized for elective surgeries were included as controls. Nasopharyngeal aspirates were tested simultaneously for cytokines interleukin (IL)-2, IL-4, IL-5, IL-10, interferon (IFN)-gamma, and tumor necrosis factor (TNF)-alpha using the Cytometric Bead Array. RESULTS: Significantly higher concentrations of IFN-gamma (p=0.0001), IL-2 (0.006), and IL-4 (p=0.0002) were observed in hBoV positive specimens than in controls. The concentration of IL-10 (p=0.04) and TNF-alpha (p=0.006) in the RSV-positive group was significantly higher than in the hBoV-positive group, while there was no difference in other cytokines concentration between the two groups. CONCLUSIONS: These results showed that both of Th1 and Th2 cytokines were increased in children with hBoV-related bronchiolitis compared to normal controls, but Th2-polarized responses were not observed.  相似文献   

18.
19.
目的 探讨细胞因子在新型甲型H1N1流感重症患者不同临床预后中作用。方法 2009年4月至2010年1月间北京佑安医院收治甲型H1N1流感重症患者28例(16例治疗痊愈,12例死亡)为研究对象,正常对照11例。Luminex技术检测血清中Th1/Th2细胞因子水平。结果 Th1类细胞因子中IL-2,IL-12 (P70),IFN-γ水平在死亡组明显低于治愈组及正常组,差异有统计学意义,P值均< 0.05。Th2类细胞因子中IL-4水平在死亡组明显低于治愈组及正常组,P=0.0012,0.031。结论 新型H1N1感染重症治愈患者、死亡患者Th1类细胞因子水平均呈下降趋势,死亡组患者下降更为明显,Th1类细胞因子水平的严重减低可能与重症患者预后不良相关。  相似文献   

20.
Apoptotic cells are readily recognized and engulfed by phagocytes and usually do not induce inflammation or tissue damage. Furthermore, they can actively suppress a pro-inflammatory response in phagocytes: In the presence of apoptotic cells, activated monocytes/macrophages produce more of the anti-inflammatory and immunoregulatory cytokines IL-10 and TGF-beta, but less of the pro-inflammatory cytokines TNFalpha, IL-1beta and IL-12. This immunoregulatory effect is most likely mediated by several receptors on monocytes/macrophages including the thrombospondin receptor (CD36). In addition to the modulation of cytokine secretion, apoptotic cell material inhibited the expression of MHC class II molecules on the surface of monocytes/macrophages. Decreased MHC II expression appeared to be mediated predominantly by increased IL-10 secretion in a para-/autocrine manner. Here, we show that the functional modulation of antigen-presenting monocytes/macrophages by apoptotic cells also influences T cell activation and function. When human peripheral blood mononuclear cells were stimulated with recall antigens in the presence of apoptotic cells, interferon gamma (IFN gamma) secretion was markedly suppressed, whereas secretion of the Th2 cytokine IL-4 was not significantly altered. Hence, apoptotic cells shift the T cell cytokine secretion pattern towards a Th2-like response. This Th2 shift can largely be prevented by neutralizing IL-10, indicating an important role of this cytokine for modulating T cell cytokine secretion patterns.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号