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91.
IL-10 displays modulatory properties on the synthesis of platelet-activating factor (PAF), a potent inflammatory mediator of vascular injury. Despite the fact that IL-10 is considered to be an anti-inflammatory cytokine, IL-10 levels correlate with disease activity in SLE. Moreover, in SLE IL-10 is unable to exert its immunosuppressive and anti-inflammatory effects. We have investigated the ability of IL-10 to stimulate PAF production from monocytes of SLE patients. Spontaneous and IL-10-stimulated PAF production by peripheral blood monocytes was measured in active (n = 13) and inactive (n = 14) SLE patients and in 15 normal control subjects. We observed that monocytes derived from patients with active SLE, but not from controls or inactive SLE, spontaneously produced significant amounts of PAF. Moreover, IL-10 enhanced the synthesis of PAF from monocytes of active SLE patients only. IL-10-induced PAF production correlated with the severity of the disease and with the extent of proteinuria. These results indicate that IL-10 only stimulates the synthesis of PAF from monocytes of SLE patients when immunologically active, suggesting that IL-10 may possess a paradoxical proinflammatory effect in SLE by promoting the production of PAF, a secondary mediator of inflammation.  相似文献   
92.
PROBLEM: A T-helper cell type 2 (Th2) cytokine dominated microenvironment has been predicted to be crucial for successful pregnancy. However, little information is available about local cytokine secretion in the human decidua. We determined the spontaneous secretion of interleukin-4 (IL-4), interferon-gamma (IFN-gamma) and IL-10 by decidual mononuclear cells at the single cell level and compared it with their secretion by peripheral blood mononuclear cells (PBMC) in the first trimester of pregnancy. METHODS OF STUDY: The cytokine secretion from decidual and blood cells was detected by a sensitive enzyme-linked immunosorbent spot-forming cell (ELISPOT)-assay. RESULTS: Cells secreting IL-4 (median 153, range 8-530), IL-10 (median 188, range 32-1600) and IFN-gamma (median 123, range 15-1140) were detected in all decidual and blood samples. The cytokine secretion showed a co-linear pattern in both the blood and decidua, i.e. when one cytokine was secreted at high levels, the others followed the trend. No correlation was found between the number of cytokine secreting cells in blood and decidua for any of the cytokines. CONCLUSIONS: Interleukin-4 and IL-10 are locally secreted in the decidua early during normal pregnancy, probably counteracting the fetal rejecting effects of co-expressed IFN-gamma. The cytokine secretion by blood cells does not generally reflect the local secretion pattern during first trimester pregnancy.  相似文献   
93.
The complete DNA nucleotide sequence of theEcoRI DNA fragment N (0.235 to 0.258 viral map units) of equine herpes virus type 2 (EHV-2) strain T400/3 was determined. This DNA fragment comprises 4237 bp with a base composition of 55.23% G+C and 44.77% A+T. Nineteen open reading frames (ORFs) of 50-287 amino acid (aa) residues were detected. ORF number 10 is located between the nucleotide position 2220 and 2756 coding for a protein of 179 amino acid residues. This protein shows significant homology to the cytokine synthesis inhibitory factor (CSIF; interleukin 10) of human (76.4%) and mouse (68.5%), and to the Epstein-Barr virus (EBV) protein BCRF1 (70.6%). The existence of an interleukin 10 (IL-10) analogous gene within the genome of the EHV-2 was confirmed by screening the genome of nine EHV-2 strains using specific oligonucleotide primers corresponding to the 5 and 3 region of this particular gene by polymerase chain reaction. In all experiments an 870 bp DNA product was amplified. The specifity of the amplified DNA fragments obtained from individual EHV-2 strains was confirmed by DNA-DNA hybridization experiments. The DNA sequence analysis of the amplified DNA products of the EHV-2 strain LK was carried out. This analysis revealed the identity of the corresponding IL-10 gene (540 bp) of this strain to the IL-10 gene of EHV-2 strain T400/3. The presented data indicate that the EHV-2 genome harbors a viral interleukin 10-like gene. This is further evidence that the IL-10 gene can be present in the genomes of members of the Herpesviridae family.  相似文献   
94.
目的:研究白细胞介素10(IL-10)对精氨酸血管加压素(AVP)诱导大鼠心脏成纤维细胞(CFs)钙调神经磷酸酶(CaN)活性的影响。方法:用培养的新生SD大鼠CFs,四氮唑盐(MTT)比色法检测CFs增殖,流式细胞仪检测细胞周期,分光光度法测定CaN活性。结果:(1)10-7 mol/L AVP组CFs的吸光度(A490)明显高于对照组(P<0.01)。IL-10呈浓度依赖性下调 AVP诱导的CFs的A490值(P<0.05或P<0.01)。IL-10本身对CFs的增殖无抑制作用。(2)10-7 mol/L AVP组CFs的S期百分率及增殖指数均明显高于对照组(均P<0.01);10-6 g/L IL-10+10-7 mol/LAVP组S期百分率及增殖指数均明显低于AVP组(P<0.01)。(3)10-7 mol/L AVP组CaN活性明显高于对照组(P<0.01);10-8、10-7、10-6和10-5g/L +10-7 mol/L AVP组的CaN活性均明显低于AVP组(P<0.01),但仍高于对照组(P<0.01或P<0.05)。IL-10呈浓度依赖性下调 AVP诱导CFs的CaN活性。结论:IL-10具有抑制AVP诱导CFs增殖和下调CFs的CaN活性的作用,这可能对预防和逆转心脏重构有一定的价值。  相似文献   
95.
Sixty-six bipolar I lithium clinic patients were studied for a history of psychotic symptoms at some time during the course of their illness. Agreement between different sources of information was calculated, and the patient population was divided into psychotic and non-psychotic subgroups. Probability of remaining well on lithium for the different subgroups was analyzed by the life table method. Psychosis during mania appeared to be associated with especially good early lithium prophylaxis.  相似文献   
96.
M Ennis  F L Pearce  C A Vernon 《Neuroscience》1979,4(9):1391-1398
The effects of antibodies to the nerve growth factor from mouse salivary gland were examined in vitro and in vivo. Treatment of explants of receptive ganglia with antibody and complement did not produce cell damage as judged by the ability of the tissue to respond to nerve growth factor. New-born mice experimentally depleted of or genetically deficient in key complement components were susceptible to the action of the antiserum.These results show that the effect of the antibody is independent of complement and are consistent with the view that it acts by neutralization of endogenous nerve growth factor.  相似文献   
97.
Vockerodt M  Haier B  Buttgereit P  Tesch H  Kube D 《Virology》2001,280(2):183-198
Infection of B cells with Epstein-Barr Virus (EBV) induces interleukin-10 (IL-10) production, which may contribute to transformation. IL-10 can modulate the immune response at certain levels, playing a crucial role in balancing humoral and cellular responses. Moreover, it can function as a growth and differentiation factor for B cells. However, the mechanism of IL-10 induction is still unclear. Here we demonstrate that IL-10 was specifically induced by the EBV-latent membrane protein 1 (LMP1) in Burkitt's lymphoma (BL) cell lines BL2 and BL41. In two T cell lines (Jurkat, MOLT3), two NHL cell lines (U266, MHH-PREB1), or three Hodgkin's disease (HD) cell lines (L428, L540, and KMH2), LMP1 did not induce IL-10 expression. In contrast, LMP1 activated CD40 or CD54 (ICAM1) expression in the analyzed cell lines. LMP1 derivatives lacking the C-terminal activation regions (CTAR), by deletion of the amino acids between 187 and 351 (Delta CTAR1) or 232 and 386 (Delta CTAR2), alone, or together induced IL-10 at very low amounts compared to wild-type LMP1. Inhibition of LMP1-mediated NF kappa B activation by constitutive repressive I kappa B-alpha only marginally impaired IL-10 expression in BL2 cells, while SB2035080 at 5 microM (a specific p38/SAPK2 inhibitor) led to reduced IL-10 expression. Our findings confirm the role of LMP1 in transactivation of cellular genes possibly important for tumor immunoescape but show that more than one signaling pathway is involved in this activation and suggests the necessity of a defined conformation of CTARs to activate IL-10 involving p38/SAPK2.  相似文献   
98.
Spleen cells from a Lewis rat immunized with affinity-purified B10 anti-(T,G)-A-L antibody were fused with the non-secreting murine hybridoma SP2/0. Cell lines secreting monoclonal antibodies specific for mu- and kappa-chains, as well as an idiotope on anti-(T,G)-A-L antibodies, were isolated and characterized. The anti-mu and -kappa antibodies, are true anti-isotypes, reacting with sera from all strains of mice tested. The anti-idiotope antibodies recognize a determinant on antibodies binding a GT-containing epitope. The proportion of anti-GAT antibody bearing the idiotope varies markedly in different murine strains. A 1000-fold higher level of antibody from Igha mice than from Ighb and Ighe mice is required to give an equivalent inhibition of the idiotope-anti-idiotope reaction. Analysis of monoclonal antibodies expressing the idiotope indicates that the affinity of binding between idiotope and anti-idiotope can vary by as much as two orders of magnitude. Immunoadsorbants prepared with anti-idiotope antibody bind suppressor factor secreted by a GAT-specific T-cell hybridoma.  相似文献   
99.
目的 观察系统性红斑狼疮(systemic lupus erythematosus,SLE)患者血清IL-10的表达与疾病活动的关系.方法 选取22例SLE患者及24名健康人作为对照,根据狼疮疾病活动指数(SLE disease activity index,SLEDAI)将SLE患者分为活动期组和非活动期组,检测血清抗dsDNA抗体,血清总补体溶血活性(CH50)及C反应蛋白(C reactive protein,CRP),酶联免疫吸附法(ELISA)检测血清IL-10表达.结果 与对照组[(18.11±6.97)ng/L]相比,IL-10在SLE活动期组[(78.54±5.62)ng/L,P<0.01]及非活动期组[(30.36±10.98)ng/L,P<0.05]均有所增高,活动期组增高更为明显(与非活动期组相比,P<0.05).IL-10水平与SLEDAI呈正相关(SLE活动期,r=0.77,P<0.01;SLE非活动期,r=0.84,P<0.01),IL-10的水平与抗dsDNA抗体(r=0.71,P<0.01)、CRP(r=0.63,P<0.01)和CH50(r=-0.56,P<0.05)均相关.结论 IL-10在SLE患者血清中表达升高,在疾病活动时更为明显,IL-10能反应疾病活动的程度,可以做为临床观察SLE疾病活动的指标之一.  相似文献   
100.
M-CSF和IL-10对人单核细胞表面分子表达的影响   总被引:1,自引:0,他引:1  
本文采用流式细胞术检测人外周血单核细胞表面CD14、CD2 3、CD6 4、CD11b、CD18、CD2 9表达 ,研究巨噬细胞集落刺激因子 (M CSF )和白细胞介素 (IL ) 10对单核细胞炎症效应和免疫效应功能的影响。结果显示 ,(1)M CSF诱导单核细胞表面CD14及CD2 3分子的表达 (P <0 0 5 )。IL 10抑制CD2 3的表达 ,促进CD6 4的表达 ,并协同M CSF诱导单核细胞CD14的表达 ,拮抗M CSF对CD2 3的诱导作用。M CSF能协同IL 10对单核细胞CD6 4的诱导作用 ;(2 )M CSF能诱导单核细胞表面CD11b及CD18的表达 (P <0 0 5 )。结论 :M CSF通过促进单核细胞表面CD11b、CD18、CD14、CD2 3的表达及协同促进CD6 4的表达而促进单核细胞粘附、炎性渗出、IgG及IgE依赖的细胞杀伤和吞噬功能 ,促进单核 巨噬细胞在炎症反应、体液免疫应答效应阶段发挥效应细胞功能。IL 10通过促进CD6 4的表达 ,增强体液免疫应答效应阶段单核 巨噬细胞的免疫效应功能 ,但通过抑制CD2 3的表达 ,下调IgE介导的体液免疫效应。  相似文献   
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