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81.
目的 探究白藜芦醇对脑小血管疾病(CSVD)大鼠神经细胞损伤及免疫因子白细胞介素-6(IL-6)、白细胞介素-10(IL-10)水平的影响。方法 将60只CSVD大鼠分为假手术组、模型组和治疗组,每组20只。通过水迷宫实验测试大鼠神经认知功能,HE染色观察大鼠海马组织病理学改变,TUNEL染色检测大鼠海马组织神经细胞凋亡率,Western blotting检测大鼠海马组织BAX/BCL-2、IL-6、IL-10蛋白的表达,酶联免疫吸附试验(ELISA)检测外周血IL-6、IL-10、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽(GSH)和丙二醛(MDA)水平。结果 模型组大鼠神经行为评分高于治疗组(P <0.05)。模型组大鼠穿越次数和停留时间少于假手术组(P <0.05),治疗组大鼠穿越次数和停留时间较模型组增加(P <0.05)。模型组大鼠海马组织神经细胞凋亡率、BAX/BCL-2蛋白表达比值高于假手术组(P <0.05),治疗组大鼠海马组织神经细胞凋亡凋亡率、AX/BCL-2蛋白表达比值低于模型组(P <0.05)。与假手术组比较,模型组... 相似文献
82.
Inflammatory foci are rich in proteases released by neutrophils (serine proteases) and macrophages (metalloproteases). These enzymes can degrade extracellular matrix proteins and cell membrane bound proteins thus contributing to the development and progression of inflammatory reaction. In this study we have investigated the influence of collagenase (metalloprotease) and trypsin (serine protease) on murine resident and oil-induced peritoneal macrophages (Mf). Short in vitro treatment of Mf, not affecting cell viability, significantly reduced the release of reactive oxygen intermediates (ROIs) and at the same time triggered the increase of IL-6 production and to lesser extent of TNF-alpha production. Both these effects were dependent on enzyme concentration used and were particularly well pronounced in resident macrophages. In addition both enzymes cleaved a number of cell-membrane molecules, including CD23, CD14, CD95L, and Mac-3. We hypothesize that the enzymatic digestion of certain Mf surface receptor proteins in inflammatory foci may be responsible for modification of cell behaviour either by preventing the generation of specific signal or alternatively by delivering a mock substitute signal to the cell interior. In effect inhibition of ROIs production limits their destructive effects and the increase in the secretion of IL-6 stimulates the synthesis of acute phase proteins and triggers other anti-inflammatory mechanisms thus directing Mf present in inflammatory foci into regulatory pathway rather than allowing them to perform solely the effector function. 相似文献
83.
细胞因子是在免疫和炎症反应中起重要作用的小分子蛋白质,克隆和研究新的细胞因子具有重要的理论意义和应用价值.我们利用抑制性减数杂交技术(SSH),从PHA刺激的U937细胞中成功克隆了一个新的细胞因子趋化素样因子1(CKLF1).CKLF1全长cDNA包括530个碱基,有一个编码99个氨基酸的完整开放读码框架.CKLF1存在其他三种变异体,命名为CKLF2,3,4,分别编码152,67和120个氨基酸,其中,CKLF2是CKIF的全基因产物.亚细胞定位和Western blot分析发现,CKLF1和CKLF3主要为分泌性表达,而CKLF2和CKLF4主要以膜结合形式表达.CKLF1与已发现的其他细胞因子之间没有明显的同源性,CKLF1在PHA刺激的U937细胞中的表达可被IL-10部分抑制.重组的CKLF1在体内外对嗜中性细胞、单核细胞和淋巴细胞具有明显的趋化活性;在体内能引起肺部明显的炎性改变,与CKLF1转基因小鼠的肺部病变相;CKLF1还能刺激骨髓细胞和小鼠骨骼肌细胞增殖.CKLF2能促进小鼠肌母C2C12细胞增殖和分化,促进BALB/c 3T3细胞增殖,并能拮抗撤血清引起的细胞凋亡,以上结果表明CKLF1可能在炎症和骨骼肌再生过程中发挥重要作用.在CKLF1,2的序列基础上,利用生物信息学方法克隆了小鼠CKLF2,4和大鼠CKLF1,2,它们与人CKLF1,2,4有相似的结构和功能;在人和小鼠CKLF的序列基础上,我们成功克隆了其他4个与CKLF有同源性的新基因,命名为趋化素样因子相关蛋白1-4(CKLF-RP1-4),它们与CKLF2有相似的结构,在16号染色体上成基因簇形式存在,因此,CKLF代表一个有重要功能的新基因超家族. 相似文献
84.
85.
In vitro comparisons of induction of perforin (PFP), granzyme B (GRB), production of cytokines, and cell-mediated cytotoxicity by interleukin-2 (IL-2), interleukin-15 (IL-15), or combinational IL-2/IL-15-induced lymphokine-activated killer cells were studied in this study. Whereas IL-2-induction was associated with a decrease in cultured cell population over a 7-day period, IL-15 alone or in combination with IL-2 resulted in significant increase including cytotoxic T lymphocytes and subsets of CD56+ lymphocytes, particularly cytokine-induced killer and cytolytic natural killer-T lymphocytes. The overall PFP, GRB, and tumor necrosis factor-alpha expression in different subtypes were also significantly higher with IL-15 alone or in combination with IL-2 induction with resultant superior cytotoxicity compared to IL-2 treatment. There was no significant advantage of addition of IL-2 over IL-15 induction. These results offer further information on the cytotoxic potency of these cytokines and their mechanisms of action implicating potential use of IL-15 as part of cytokine adoptive immunotherapy. 相似文献
86.
IL-8 mRNA in human gingival epithelial cells (HGECs) is up-regulated by Fusobacterium nucleatum, and up-/down-regulated by Porphyromonas gingivalis in a complex interaction in the early stages (< or = 4 h) after infection. The mechanisms involved in this regulation in response to F. nucleatum and/or P. gingivalis infection, and identification of co-regulated cytokine genes, are the focus of this investigation. Heat, formalin or protease treatment of F. nucleatum cells attenuated the IL-8 mRNA up-regulation. NF-kappaB, mitogen-activated protein kinase (MAPK) p38 and MAPK kinase/extracellular signal-regulated kinase (MEK/ERK) pathways were involved in IL-8 mRNA induction by F. nucleatum. Pretreatment of P. gingivalis with heat, formalin or protease enhanced IL-8 mRNA induction. NF-kappaB, MARK p38, and MEK/ERK pathways were also involved in this induction. In contrast, down-regulation of IL-8 mRNA by P. gingivalis involved MEK/ERK, but not NF-kappaB or MAPK p38 pathways. cDNA arrays analysis revealed that mRNA down-regulation by P. gingivalis is a specific reaction that only a number of genes, e.g. IL-1beta, IL-8, macrophage inflammatory protein-2alpha, and migration inhibitory factor-related protein-14, are affected based on examination of 278 cytokine/receptor genes. These data indicate that F. nucleatum and P. gingivalis trigger specific and differential gene regulation pathways in HGECs. 相似文献
87.
88.
血浆TPO水平变化与血小板减少疾病的关系 总被引:2,自引:0,他引:2
目的:探讨血浆血小板生成素(Thrombopoietin,TPO)水平变化与血小板减少疾病的关系。方法:采用多抗夹心酶联免疫吸附法对68例各种不同原因致血小板减少患者通过应用白介素-11(rhIL-11)来动态检测TPO水平,rhIL-11剂量为25μg/(kg.d),皮下注射,连用10天。结果:(1)急性白血病(Acute leukemia,AL)化疗后血小板减少患者TPO水平低于正常对照组;再生障碍性贫血(Aplastic anemia,AA)及骨髓增生异常综合征(Myelodysplastic syndrome,MDS)患者TPO水平高于正常对照组;原发性血小板减少性紫癜(Idiopathic thrombocytopenic purpura,ITP)及肝硬化(Liver cirrhosis)患者TPO水平与正常对照组无明显差异。而其中的白血病化疗后血小板减少患者和AA患者的骨髓巨核细胞数较TPO正常组显著降低。(2)上述疾病患者用rhIL-11有效者TPO水平趋于正常,无效或疗效欠佳者,则TPO无变化。有效者TPO水平与血小板计数呈负相关。结论:血浆TPO检测,有助于临床鉴别各种血小板减少疾病的病因,对血小板减少患者合理应用rhIL-11提供理论的依据。 相似文献
89.
Krásná E Kolesár L Slavcev A Valhová S Kronosová B Jaresová M Stríz I 《Inflammation》2005,29(1):33-37
IL-18 is a multifunctional cytokine that augments both innate and acquired immunity and potentiates Th1 and Th2 reactions.
We studied the expression of IL-18 receptor (IL-18R) on renal and respiratory epithelial cell lines. Both cell lines upregulated
IL-18R mRNA and IL-18R membrane expression in response to TNF alpha and other proinflammatory cytokines. The function of IL-18R
was confirmed by induction of IL-8 release from epithelial cells in response to recombinant IL-18. Epithelial cells may represent
an important target for IL-18, mainly under inflammatory conditions associated with TNF alpha release. 相似文献
90.
Functional topography of discrete domains of human CD38 总被引:6,自引:0,他引:6
Ausiello CM Urbani F Lande R la Sala A Di Carlo B Baj G Surico N Hilgers J Deaglio S Funaro A Malavasi F 《Tissue antigens》2000,56(6):539-547