槲皮素对LPS延迟中性粒细胞自发性凋亡效应的抑制作用

目的：研究槲皮素对接受细菌脂多糖(LPS)刺激的中性粒细胞(PMN)自发性凋亡的影响，探讨槲皮素的抗炎作用机制。方法：以人外周血PMN为研究对象，选择光镜和流式细胞术检测细胞凋亡情况，对裂解的片段化DNA进行定量(二苯胺测定法)和定性(琼脂糖凝胶电泳)分析。结果：槲皮素(1～100μmol／L)对PMN的自发性凋亡率并无影响，但却能部分恢复由LFS所延迟的PMN自发性凋亡进程。当槲皮素的浓度为40μmol／L时，其恢复作用达到最大。结论：槲皮素对LPS延迟PMN自发性凋亡的效应产生了抑制作用，减轻了因预激因子活化PMN而加重的炎症反应，部分揭示了槲皮素的抗炎作用机制。     

槲皮素对LPS诱导的中性粒细胞产生白介素6的影响

目的 研究离体培养的人中性粒细胞在被LPS激活的情况下,槲皮素对中性粒细胞产生IL-6的影响。方法 运用ELISA法检测槲皮素对LPS诱导的中性粒细胞分泌IL-6的影响;运用流式细胞术检测槲皮素对LPS活化的中性粒细胞内IL-6的蛋白水平的影响;运用逆转录PCR（RT-PCR）技术检测槲皮素对LPS活化的中性粒细胞表达IL-6 mRNA的影响。结果 在无刺激的情况下中性粒细胞不产生IL-6,LPS（1μg／mL）以时间依赖性的方式诱导中性粒细胞表达IL-6 mRNA,合成并分泌IL-6,并在16h达到高峰。然而,预先用槲皮素（40μmol／L）处理中性粒细胞30min后,LPS诱导的中性粒细胞表达IL-6 mRNA,合成并分泌IL-6则受到了抑制。结论IL-6是炎症早期重要的促炎症因子。因此,槲皮素抑制LPS诱导中性粒细胞产生IL-6,提示槲皮素可能通过对炎症因子负性调控而发挥其抗炎作用。     

缺血预适应阻抑犬冠状窦血中性粒细胞CD11b/CD18的表达

本文旨在探讨缺血预适应（ＩＰ）心肌保护效应是否与其防止中性粒细胞（ＰＭＮ）ＣＤ１１ｂ／ＣＤ１８分子的表达有关。采用犬衣降支动脉（ＬＡＤ）建立ＩＰ模型,在长缺血前各５ｍｉｎ血和再灌注,反复４次,于基础、缺血前、缺血１ｈ、再灌注０．５和２ｈ分别采集冠状窦血作式细胞仪分析ＰＭＮＣＶＤ１１ＣＤ１８的表达,并一单纯ＩＲ组比较。ＩＲ组在心肌缺因与再灌注各时点ＰＭＮＣＤ１１ｂ／ＣＤ１８表达均显著增加,而ＩＰ组除     

不同复苏溶液对失血性休克大鼠中性粒细胞CD11a、CD11b表达的影响

目的观察不同复苏溶液对失血性休克大鼠PMN表面CD11a、CD11b表达的影响.方法成年Wistar大鼠随机分为0.9%NaCl(NS)、7.5%NaCl(HS)、5%NaCl-3.5%NaAc(HSA)三组,每组6只.动物麻醉后,自股动脉放血,于10min内使MAP下降至5.07-5.47kPa,维持90min.按4mL/kg体重分别注入NS、HS、HSA,5min内输完.随后输注三倍最大失血量的复方氯化钠溶液,40min内输完.分别于休克前、后、给液后1.5h、3h、6h取血0.2mL,流式细胞仪测定PMN表面CD11a、CD11b表达的变化.结果休克后,各组PMN表面CD11a表达下降,但与休克前比较无显著差别.给液后1.5h,各组CD11a表达继续下降;给液后3h,各组CD11a表达稍有回升;给液后6h,各组CD11a表达又呈下降趋势,HSA组CD11a表达显著低于休克前水平;各组间于各时相点均无显著差别.休克后,各组PMN表面CD11b表达增加,与休克前比较有非常显著差别.给液后3h内,各组CD11b表达随观察时间的延长呈进行性增加;给液后6h,NS组CD11b表达继续增加,HS组和HSA组CD11b表达有下降趋势.各组CD11b表达于给液后各时相点均较休克前和休克时非常显著增加,HS组和HSA组CD11b表达于给液后各时相点均低于NS组,但无显著差别.结论液体复苏后,失血性休克大鼠PMN表面CD11a表达呈下降趋势,CD11b表达呈上升趋势,HS和HSA有减弱这种趋势的作用.     

白蛋白对脂多糖诱导中性粒细胞胞外诱捕网生成的抑制作用

目的探讨白蛋白对脂多糖(LPS)诱导人外周血中性粒细胞胞外诱捕网(neutrophil extracellular traps,NETs)生成的抑制作用及机制。方法分离人外周血中性粒细胞,分别培养于无白蛋白和含生理浓度白蛋白的培养体系中,加入LPS刺激,同时使用钙离子(Ca²⁺)以及自噬调节剂干预,采用sytox green染色法检测NETs,采用Fluo-4 AM染色法检测胞内Ca²⁺水平,免疫荧光法检测NETs相关蛋白髓过氧化物酶(MPO)、弹性蛋白酶(NE)和瓜氨酸化组蛋白H3(cit-H3)以及自噬体相关蛋白LC3B的表达。结果 LPS可诱导中性粒细胞释放NETs,白蛋白可抑制NETs生成;白蛋白可降低LPS刺激下中性粒细胞胞内Ca²⁺浓度和自噬水平。Ca²⁺载体可增强中性粒细胞自噬水平并促进LPS诱导的NETs生成,Ca²⁺螯合剂可降低自噬水平并抑制NETs生成。自噬激动剂可显著增强NETs,自噬抑制剂则显著抑制NETs。结论白蛋白对LPS诱导中性粒细胞胞外诱捕网(N...     

严重烧伤病人PMNCD11b/CD18受体表达及特异性iRNA对其调节作用

本文探讨了严重烧伤对病人外周血中性粒细胞 (PMN)CD11b/CD18受体表达的影响及特异性免疫核糖核酸 (iRNA)对其调节作用。结果发现 :(1)严重烧伤病人PMNCD11b/CD18受体表达率明显下降 ,至伤后第 10天时 ,分别只有正常的6 7 1%和 6 8 9% ,且其下降程度与烧伤面积成正比 ;(2 )伤后早期应用特异性iRNA可明显提高烧伤病人PMNCD11b/CD18受体表达率 ;(3)临床观察发现 ,治疗组伤后创面细菌培养阳性率 ,创面脓毒症及菌血症的发生率明显低于对照组 (P均 <0 0 5 ) ,创面愈合时间明显短于对照组 (P <0 0 1)。该结果为临床应用特异性iRNA防治烧伤后感染提供了实验依据。     

中性粒细胞介导组织损伤的机理

中性粒细胞（ＰＭＮ）介导组织损伤的机制主要包括两个方面：（１）ＰＭＮ被激活，并在趋化因子的作用下聚集于组织中；（２）激活的ＰＭＮ通过“呼吸爆发”和脱颗粒作用，产生大量的氧自由基、蛋白颗粒酶以及细胞因子等炎性介质，引起组织细胞的损伤，乃至多器官功能衰竭的发生     

高渗盐水预处理可减轻中性粒细胞介导的肝脏缺血再灌注损伤

目的：探讨高渗盐水预处理对肝脏缺血再灌注损伤的拮抗作用及其机制。方法：建立大鼠局部肝脏缺血再灌注模型。设假手术组（sham组）、缺血再灌注组（IR组）和高渗盐水预处理组（HTS组），分别于再灌注后1 h、3 h、6 h、12 h和24 h处死大鼠，测定谷丙转氨酶（ALT）；抗凝血流式细胞仪测定中性粒细胞CD11b/CD18(Mac-1)的阳性率；RT-PCR和Western blotting分别测定肝内细胞间黏附分子1（ICAM-1）的mRNA和蛋白表达；比色法测定肝脏内髓过氧化物酶（MPO）活性；常规病理及电镜观察肝脏的病理学改变及肝脏内中性粒细胞的浸润情况。结果： ① HTS组在3 h、6 h和12 h血清ALT水平明显低于IR组（P<0.05）。②HTS组在6 h和12 h中性粒细胞Mac-1表达显著弱于IR组（P<0.05）。③HTS组肝脏MPO活性在再灌注后6 h、12 h和24 h明显低于IR组（P<0.05）。④HTS组大鼠肝脏内ICAM-1mRNA及蛋白表达明显低于IR组。⑤HTS组肝内中性粒细胞浸润、肝细胞浊肿和肝窦狭窄程度轻于IR组。结论： HTS预处理能够通过抑制中性粒细胞Mac-1和肝内ICAM-1的表达，明显抑制肝内中性粒细胞的黏附和聚集，起到拮抗肝脏缺血再灌注损伤的作用。     

中性粒细胞呼吸爆发的产生机制及其炎症效应

中性粒细胞的呼吸爆发功能在宿主防御及炎症反应中起着重要的作用。该反应起始于吞噬小体表面的NADPH氧化酶的活化，它将O2还原成O2^-，随后O2^-经歧化作用转变成H2O2。在有Cl^-的情况下，髓过氧化物酶可以催化H2O2生成HOCl。HOCl是高效的杀菌剂，通过与邻近的巯基、氨基反应发挥其杀伤毒性。呼吸爆发在清除微生物的同时也会对机体正常组织造成损伤，许多疾病的发生均与活性氧的代谢有关。     

中性粒细胞CD64表达在疾病诊疗中的应用进展

中性粒细胞CD64的表达可用于细菌感染所引起的感染性疾病的早期诊断,如败血症,呼吸道感染,烧伤和术后感染等,以及自身免疫性、炎症性疾病的活动期和合并感染的鉴别诊断.不同的临界值的划分,使中性粒细胞CD64表达也可应用于非感染性炎症性疾病的活动性和严重程度判断.若将CD64联合其他炎症性指标共同检测,可提高诊断的敏感性和特异性,也可更好地鉴别细菌感染和病毒感染.中性粒细胞CD64表达的检测有利于疾病辅助诊断、病情监测、预后判断、疗效评估、以及指导临床用药等,具有广阔的临床应用前景.     

Quercetin inhibits LPS-induced delay in spontaneous apoptosis and activation of neutrophils

Objective: To investigate the effects of quercetin, an herbal flavonoid, on LPS-induced delay in spontaneous apoptosis, adhesion molecules (CD62L, CD11b/CD18) expression of neutrophils, and superoxide (O₂⁻) generation by LPS-primed fMLP-induced human neutrophils. Methods: Neutrophils were incubated in the presence or absence of lipopolysaccharide (LPS) at a final concentration of 1 μg/ml for 24 hours. Some wells with neutrophils were pre-treated with quecetin at the final concentration ranging from 0–100 μM for 30 min and then 1 μg/ml LPS was added into the cultures for 24 hours. The apoptosis of neutrophils was evaluated by flowcytometry analysis of propidum iodide (PI)-staining of the nuclei and annexin V staning of phosphatidylserine (PS) in the cell membrane. Agarose gel electrophoresis of low molecular weight DNA was performed to analyze DNA fragmentation. The effects of quercetin on adhesion molecules were detected by using flowcytometry analysis. The generation of O₂⁻ by LPS-primed fMLP-induced neutrophils was determined by reduced cytochrome c assay. Results: LPS markedly inhibited the spontaneous apoptosis of neutrophils, but the inhibitory effect was abrogated after the pre-treatment of neutrophils with quercetin (~40 μM) for 30 min. Quercetin (40 μM) also prevented LPS-induced down-regulation of CD62L expression, up-regulation of CD11b/CD18 expression, and O₂⁻ generation by fMLP-induced neutrophils. Conclusion: As one of the pro-inflammatory factors, LPS aggravates inflammation through priming neutrophils to synthesize/release cytotoxic contents and prolonging functional lifespan of neutrophils by delaying the spontaneous apoptosis. Thus, our data suggest to us that quercetin might decrease the susceptibility of neutrophils to pro-inflammatory factors (e. g. LPS), which could partially explain the anti-inflammatory mechanisms of quercetin. Received 5 May 2005; returned for revision 26 August 2005; accepted by I. Ahnfelt R?nne 5 September 2005     

益活清胰Ⅰ号对重症急性胰腺炎大鼠中性粒细胞与内皮细胞黏附的抑制作用

目的观察益活清胰Ⅰ号对重症急性胰腺炎(severe acute pancreatitis,SAP)大鼠的中性粒细胞(polymorphonuclear cell,PMN)-内皮细胞(endothelial cell,EC)黏附率及PMN表面黏附分子CD11/CD18表达的影响,探讨其治疗SAP的机理。方法81只SD大鼠随机分为假手术组(n=27)、造模组(n=27)、治疗组(n=27),SAP模型采用5%的牛磺胆酸钠胰胆管逆行注射方法建立。6、12、24h分批处死动物9只采集动脉血和胰腺组织标本,测定胰腺组织的MPO活性,HE染色光镜下观察胰腺组织的病理变化。分离PMN,与体外培养的血管内皮细胞作用测定PMN-EC黏附率,ELISA法测定PMN表面CD11a/CD18、CD11b/CD18。结果与假手术组比较,造模组和治疗组术后各时点胰腺组织MPO活性、PMN-EC黏附率、PMN表面CD11a/CD18和CD11b/CD18均增高(P<0.01),治疗组术后各时点胰腺组织MPO活性、PMN-EC黏附率、PMN表面CD11a/CD18和CD11b/CD18均显著低于造模组(P<0.01)。造模组胰腺组织出血和坏死严重,治疗组的病理损伤明显减轻。结论益活清胰Ⅰ号能降低PMN表面CD11a/CD18和CD11b/CD18的表达水平,减轻PMN与EC的黏附,从而有助于减轻PMN与EC黏附所致的胰腺组织病理损伤。     

地奥司明对肾缺血再灌注大鼠肾组织MPO和中性粒细胞CD11b、CD54及CD62L水平的影响

 目的：观察地奥司明（DOSM）对肾缺血/再灌注（I/R）大鼠肾组织髓过氧化物酶（MPO）和中性粒细胞CD11b、CD54及CD62L表达水平的影响。方法: 180只SD大鼠随机分成3组:假手术组(SO)、肾缺血/再灌注模型组(I/R)和地奥司明+肾缺血/再灌注模型组(DOSM+I/R)。采用ELISA方法测定肾脏组织中MPO的水平,流式细胞分析法检测中性粒细胞表面CD11b、CD54和CD62L的表达水平。结果: 在1h、3h、6h、12h、24h和48h不同时间点的肾组织中,I/R和DOSM＋I/R两组MPO活性均随时间逐渐升高,于6h达最高,后逐渐下降,两组相比有显著性差异（P＜0.05或P＜0.01）。中性粒细胞CD11b、CD54及CD62L的表达在相同时段I/R组显著高于SO组（P＜0.05或P＜0.01);而在DOSM+I/R组显著低于I/R组（P＜0.05或P＜0.01)。结论：DOSM可显著降低肾I/R病理过程中MPO活性,显著降低中性粒细胞CD11b、CD54及CD62L的表达,有助于减轻I/R时炎性细胞的浸润。     

吞噬感染与非感染凋亡粒细胞对人巨噬细胞的活化具有不同影响

目的　探讨感染与非感染诱导的凋亡中性粒细胞对人巨噬细胞 (MΦ)活性的影响。方法　用大肠杆菌 (E .coli)或金黄色葡萄球菌 (S .aureus)感染中性粒细胞 ,或经紫外线照射 ,以诱导其凋亡 ,观察吞噬这些凋亡细胞对人MΦ活性的影响。结果　吞噬照射诱导的凋亡粒细胞通过降低TNF α和增加TGF β来抑制MΦ活性。与此相反 ,吞噬感染所致的凋亡细胞可明显增加MΦ的TNF α产量并上调CD6 4 (FcγRⅠ )的表达。结论　粒细胞凋亡是调控免疫和炎症反应的一个重要机制。在炎症早期 ,粒细胞凋亡多由病原感染所致 ,吞噬这些细胞可激活MΦ而有助于控制病原 ;一旦病原被清除 ,在感染灶的多余粒细胞发生凋亡 ,吞噬这些非感染凋亡细胞可抑制MΦ活性 ,从而有助于炎症的消退并减少组织损伤     

Increased expression of surface activation markers on neutrophils following migration into the nasal lumen

BACKGROUND : The sequence of events following the recruitment of a free-flowing neutrophil in the peripheral circulation, via adhesion, migration and release of mediators, to a neutrophil on the surface of the nasal epithelium is a co-ordinated process. Little is known about the state of neutrophil activation following this course of events. OBJECTIVES : To investigate the expression of surface activation markers on neutrophils, reflecting activation during their recruitment to the nose, and to see whether the inflammatory process during allergic rhinitis influences this process. METHOD : Nine healthy controls and 12 patients with grass pollen-induced intermittent allergic rhinitis were investigated during the peak of the pollen season. The expression of CD11b, CD66b and CD63 on the neutrophil cell surface, as a reflection of activation, was analysed using flow cytometry. Neutrophils were derived from peripheral blood and nasal lavage fluid. In addition, eosinophil cationic protein (ECP) and myeloperoxidase (MPO) as well as L-, P- and E-selectins in the nasal lavage fluid were analysed using RIA and ELISA, respectively. RESULTS : A marked increase in the expression of all three CD markers on the neutrophil cell surface was noticed following migration from the bloodstream to the surface of the nasal mucosa. At the peak of the grass pollen season, the MPO levels increased, reflecting an increase in the total number of nasal fluid neutrophils. In parallel, the expression of CD11b was further augmented. The expression of the CDb11b was reduced on neutrophils remaining in the circulation. In addition, the level of L-selectin was reduced on neutrophils derived from the blood during allergic inflammation. CONCLUSION : Neutrophils might become activated during their transfer from the blood to the surface of the nasal mucosa, but these changes may also be due to depletion of activated neutrophils in the blood via activated endothelial/epithelial adhesion and chemoattractant measures. The increased expression of surface activation markers during allergic rhinitis suggests roles for neutrophils in the inflammatory process.