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51.
为进一步探讨细胞免疫对AA发病的影响,阐明细胞因子在AA患者中变化的基础与临床意义,采用酶联免疫试剂盒ELISA法对38例AA患者及20例正常人外周血单个核细胞(PBMNC)培养上清诱生G-CSF,IL-6,TNFα,IFNα及IL-8水平进行测定,同时采用改良APAAP法观察外周血T细胞亚群及HLA-DR抗原表达,结果AA患者PBMNC培养上清中G-CSF阳性率减低,IL-6,TNFαIFNα及 相似文献
52.
Satoshi Takahashi Dawn D. Tooley Levente Kapás Jidong Fang Jerome M. Seyer James M. Krueger 《Pflügers Archiv : European journal of physiology》1995,431(2):155-160
Tumor necrosis factor (TNF) is a cytokine that possesses many biological activities, including enhancement of non-rapid-eye-movement sleep (NREMS). The role of endogenous TNF in the regulation of spontaneous sleep is unknown. If TNF is involved in sleep regulation, then reduction of endogenous TNF should suppress spontaneous sleep. A soluble TNF-binding protein I (TNF-BP I) and a synthetic fragment of TNF-BP I, TNF-R-(159–178), that contains the biologically active region of TNF-BP I, were used. These substances bind TNF and possess TNF-inhibitory activity; their effects on rabbit sleep after intracerebroventricular injection were determined across a 6-h recording period. Two doses of TNF-BP I (0.05 g and 0.5 g) were administered; the higher dose of TNF-BP I significantly decreased NREMS. Four doses of TNF-R-(159–178) (0.25 g, 2.5 g, 25 g and 50 g) were used. The 25 g and 50 g doses significantly suppressed NREMS. The highest dose (50 g) also decreased REM sleep. These results are consistent with the hypothesis that endogenous brain TNF is involved in the regulation of normal sleep. 相似文献
53.
54.
Sigmundsdóttir H Johnston A Gudjónsson JE Valdimarsson H 《Clinical immunology (Orlando, Fla.)》2004,111(1):119-125
At both cutaneous and mucosal sites, interleukin (IL)-10, IL-12 and transforming growth factor (TGF)-beta are important regulators of chronic inflammatory disease, where cutaneous lymphocyte-associated antigen (CLA) and alphaE integrin (CD103) may be expressed. Stimulation with streptococcal pyrogenic exotoxin C (SpeC) increased the expression of CD103 by CD8+ but not CD4+ T cells. While adding IL-12 augmented the expression of CLA, superantigen-induced expression of CD103 was markedly suppressed by IL-12, which could be reversed by TGF-beta. Antibodies against TGF-beta inhibited, and a combination of anti-TGF-beta and IL-12 completely abrogated the induced CD103 expression. IL-10 strongly decreased the frequency of CLA+ and although not increasing the frequency of CD103+CD8+ T cells, the amount of CD103 expressed per cell was markedly increased. Thus, the expression of CLA and CD103 may be antagonistically regulated by IL-10 and IL-12 and the balance between these cytokines could influence the T cell migration of inflammatory cells into epithelial tissues. 相似文献
55.
J. Börgermann S. Flohé R. J. Scheubel O. Kuss A. Simm F. U. Schade I. Friedrich 《Inflammation research》2007,56(3):126-132
Objective and design: Cardiopulmonary bypass (CPB) impairs monocyte and neutrophil proliferation, cytokine synthesis, and antigen presentation.
This study compares in vivo data with results from an extracorporeal circulation (ECC) model, distinguishing direct effects on cytokine synthesis from
regulatory mechanisms.
Patients and methods: Whole blood from 18 patients prior to, during and after CPB was stimulated with lipopolysaccharide (LPS). Tumor necrosis factor
(TNF)-α, interleukin (IL)-6, and IL-8 levels were measured. Additionally, blood from 4 volunteers was circulated in an ECC
model. Cytokine levels were measured before and during mock ECC.
Results: LPS-induced cytokine synthesis was reduced after CPB (TNF-α: 11 %; IL-6: 29 %; IL-8: 48 % of preoperative values, all p <
0.001). In mock ECC, cytokine production (except IL-8) was suppressed: TNF-α production was lowest 60 min after starting ECC,
IL-6 synthesis was lowest at 90 min (33 % and 15 % vs. pre-ECC levels; both p < 0.001). Patient sera contained cytokine-inhibitory
activity after CPB, an activity not found in mock ECC.
Conclusions: (1) In patients, CPB induces early transient LPS hyporesponsiveness; (2) blood contact with foreign surfaces induces LPS hyporesponsiveness;
(3) serum cytokineinhibitory activities are released after CPB, but not in mock ECC. Impaired leukocyte function may explain
increased susceptibility to infections after CPB.
Received 16 September 2006; accepted without revision by K. Visvanathan 18 October 2006 相似文献
56.
Elliott DE Setiawan T Metwali A Blum A Urban JF Weinstock JV 《European journal of immunology》2004,34(10):2690-2698
Inflammatory bowel disease (IBD) is prevalent in industrialized countries, but rare in less-developed countries. Helminths, common in less-developed countries, may induce immunoregulatory circuits protective against IBD. IL-10(-/-) mice given piroxicam develop severe and persistent colitis. Lamina propria mononuclear cells from colitic IL-10(-/-) mice released IFN-gamma and IL-12. The ongoing piroxicam-induced colitis could be partially blocked with anti-IL-12 monoclonal antibody suggesting that the inflammation was at least partly IL-12 dependent. Colonization of piroxicam-treated colitic IL-10(-/-) mice with Heligmosomoides polygyrus (an intestinal helminth) suppressed established inflammation and inhibited mucosal IL-12 and IFN-gamma production. H. polygyrus augmented mucosal IL-13, but not IL-4 or IL-5 production. Transfer of mesenteric lymph node (MLN) T cells from IL-10(-/-) animals harboring H. polygyrus into colitic IL-10(-/-) recipients inhibited colitis. MLN T cells from worm-free mice did not. Foxp3 (scurfin) drives regulatory T cell function. H. polygyrus enhanced Foxp3 mRNA expression in MLN T cells that had regulatory activity. This suggests that H. polygyrus inhibits ongoing IL-10(-/-) colitis in part through blocking mucosal Th1 cytokine production. Resolution of inflammation is associated with increased IL-13 production and can be adoptively transferred by MLN T cells. 相似文献
57.
目的:研究严重烫伤后血IL-6和IL-1α对中性粒细胞(PMN)凋亡的影响。方法:复制30%体表面积Ⅲ度烫伤大鼠模型;分离PMN,TUNEL荧光标记,流式细胞仪分析细胞凋亡;PMNcaspase3活性以荧光免疫吸附酶法测定;血清IL-6和IL-1α水平以酶联免疫法测定。结果:血清IL-6水平(μg/L)在伤后各组(3、6、12、24、48h依次分别为9.14±1.16、12.49±1.14、3.01±0.75、1.41±0.28和1.56±0.43)和IL-1α水平(ng/L)在伤后3、6、12h组(90.08±8.39、320.93±14.48和47.84±5.19)均分别显著高于伤前对照组IL-6(0.24±0.07)和IL-1α(27.65±4.86)水平(P<0.05);伤后各组PMN凋亡率(%)按时点依次为9.89±2.00、4.98±1.35、1.31±0.72、2.49±1.87和6.88±1.13显著少于伤前组13.66±3.88(P<0.05);PMNcaspase-3的活性测定结果与PMN的凋亡表现相一致。结论:大鼠烫伤后外周血PMN凋亡明显延迟;IL-6和IL-1α等细胞因子是重要的影响因素,减少细胞内caspase-3的激活可能是其机制之一。 相似文献
58.
59.
Amy C. Fuchs Eric V. Granowitz Leland Shapiro Edouard Vannier Gerhard Lonnemann Jonathan B. Angel Jeffrey S. Kennedy Arthur R. Rabson Elaine Radwanski Melton B. Affrime David L. Cutler Paul C. Grint Charles A. Dinarello 《Journal of clinical immunology》1996,16(5):291-303
We conducted a double-blind, placebo-controlled study to investigate the safety, pharmacokinetics, and immunological properties of interleukin-10 (IL-10) administration in healthy humans. Volunteers received a single intravenous bolus injection of recombinant human IL-10 (1, 10, or 25g/kg) or placebo. Cytokine production in whole blood and peripheral blood mononuclear cells (PBMC) was assessed before and 3, 6, 24, and 48 hr after the injection. Peak serum concentrations of IL-10 (15±1.1, 208±20.1, and 505±22.3 ng/ml) occurred after 2–5 min for 1, 10, and 25g/kg IL-10, respectively. The terminal-phase half-life was 3.18 hr. A transient leukocytosis (24–63% above baseline) was observed 6 hr after injection, which coincided with a dose-dependent decrease (12–24%) in neutrophil superoxide generation. There was a marked inhibition (60–95%) of endotoxin-induced IL-6 production from whole blood in each group receiving IL-10. Production of IL-8 in endotoxin-stimulated blood was reduced in the 10g/kg group. In PBMC stimulated with phytohemagglutinin and phorbol ester, there was a decrease (72–87%) in interferon- (IFN) production 6 hr after IL-10 with a return to pre-IL-10 levels after 24 hr. This reduction was only partially associated with a decrease in the number of CD2-bearing cells. We conclude that IL-10 administration into humans is without significant side effects, and a single injection reducesex vivo production of IL-6, IL-8, and IFN. 相似文献
60.
目的:探讨哮喘患者痰液嗜酸性粒细胞凋亡(EOS)与IL-5和sIL-2R的关系。方法:选择哮喘患者(哮喘组)急性发作期和缓解期30例,20名健康人(正常组)作对照。分别采用ELISA法测定患者痰液白细胞介素5(IL-5)和可溶性白介素2受体(sIL-2R),应用流式细胞仪检测痰液EOS凋亡。结果:哮喘患者急性发作期和缓解期痰液中IL-5和sIL-2R明显升高,EOS凋亡率增高,而正常组未发现EOS凋亡。急性发作期哮喘患者EOS凋亡率与IL-5呈明显的负相关,r为~0.78。结论:哮喘患者气道局部有EOS凋亡现象,并受到IL-5相互作用的调节。sIL-2R与EOS凋亡率无明显的相关性。 相似文献