休克淋巴液对肠系膜微淋巴管内皮细胞炎症介质表达的影响

目的：观察休克淋巴液对大鼠肠系膜微淋巴管内皮细胞（MMLEC）诱生型一氧化氮合酶（iNOS）、肿瘤坏死因子（TNF-α）、白细胞介素6（IL-6）表达的影响，探讨休克淋巴液损伤MMLEC的机制。方法：正常大鼠MMLEC原代培养，应用第三代MMLEC进行研究。无菌条件下复制大鼠重症失血性休克模型（血压40 mmHg，维持90 min），引流休克时肠淋巴液及门静脉血，并以正常肠淋巴液、门静脉血作为对照。以4%终浓度的休克淋巴液作用MMLEC 6 h，以休克血浆、正常淋巴液、正常血浆、胎牛血清（FBS）、DMEM培养液作为对照。提取MMLEC的cDNA，RT-PCR检测iNOS、TNF-α及IL-6 mRNA的表达；同时检测培养上清液MDA、NO、TNF-α及IL-6含量的变化。结果：4%终浓度的休克淋巴液作用6 h后，MMLEC的iNOS、TNF-α、IL-6 mRNA表达以及培养上清液MDA、NO、TNF-α和IL-6水平显著高于正常淋巴液组、休克血浆组、正常血浆组、FBS组以及DMEM组；且休克血浆作用MMLEC 6 h后的iNOS、TNF-α、IL-6 mRNA表达以及培养上清液的MDA、NO、TNF-α及IL-6水平显著高于正常淋巴液组、正常血浆组、FBS组以及DMEM组。结论：休克淋巴液可使大鼠MMLEC的 iNOS、TNF-α及IL-6 mRNA表达增强，促进自由基释放，从而诱导细胞损伤。     

休克淋巴液对大鼠内皮细胞VEGF表达的影响

目的观察休克淋巴液对大鼠肺微血管内皮细胞(PMVEC)、肠系膜微淋巴管内皮细胞(MMLEC)、血管内皮生长因子(VEGF)表达的影响。方法无菌条件下复制大鼠重症失血性休克模型,引流休克时肠系膜淋巴液或收集门静脉血,同时收集正常淋巴液及门静脉血作为对照。以4%终浓度的处理因素与第3代PMVEC及MMLEC共同孵育6h,RT-PCR测定VEGF mRNA表达。结果不同处理因素与PMVEC及MMLEC孵育6h后,休克淋巴液组两种内皮细胞的VEGF mRNA表达均显著低于休克血浆组、正常淋巴液组、正常血浆组、胎牛血清(FBS)组、DMEM组;休克血浆组显著低于正常淋巴液组、正常血浆组、FBS组和DMEM组;其它组间无统计学差异。结论休克淋巴液可抑制内皮细胞的VEGF mRNA表达,且作用强于休克血浆。     

Vascular Endothelial Cell Injury Partly Induced by Mesenteric Lymph in Heat Stroke

Animal models have shown that mesenteric lymph plays important roles in the pathogenesis of endothelium injury in many critical ill states. Gut-derived septicemia and endothelium injury are the two key pathogenesis of heat stroke (HS); however, it is unclear whether mesenteric lymph is cytotoxic to endothelium in HS. HS rat models were prepared in a prewarmed incubator. Mesenteric lymph, collected pre-, during, and post-HS, was analyzed for biological activity on human umbilical vein endothelial cell (HUVEC) in vitro. The effect of HS lymph on the production of von Willebrand factor (vWF), thrombomodulin (TM), and IL-6 by HUVEC was investigated. In vivo, vascular endothelium injury biomarkers, circulating endothelial cell (CEC), as well as serum soluble vWF and TM were tested in rats of HS and HS with mesenteric lymph duct ligation (HS-LDL). HS but not heat stroke sham mesenteric lymph-injured endothelial cells showed significantly increased HUVEC cytotoxicity and enhanced HUVEC monolayer permeability as well as elevated levels of vWF and TM production by HUVEC. IL-6 production by HUVEC was augmented by HS lymph in vitro. The effects of HS lymph on IL-6 production had a time course resembling that of the toxic effects of HS lymph on HUVEC. In vivo, when compared with HS rats, decreased CEC counts as well as lower serum vWF and TM concentrations were detected in HS-LDL rats. HS mesenteric lymph is probably harmful to vascular endothelium, which indicates that the modulation of mesenteric lymph may have some potential benefits to HS.     

Cell Death Mechanisms Induced by Cytotoxic Lymphocytes

One of the functions of the immune system is to recognize and destroy abnormal or infected cells to maintain homeostasis. This is accomplished by cytotoxic lymphocytes. Cytotoxicity is a highly organized multifactor process. Here, we reviewed the apoptosis pathways induced by the two main cytotoxic lymphocyte subsets, natural killer （NK） cells and CD8^＋T cells. In base to recent experimental evidence, we reviewed NK receptors involved in recognition of target-cell, as well as lytic molecules such as perforin, granzymes-A and -B, and granulysin. In addition, we reviewed the Fas-FasL intercellular linkage mediated pathway, and briefly the cross-linking of tumor necrosis factor （TNF） and TNF receptor pathway. We discussed three models of possible molecular interaction between lytic molecules from effector cytotoxic cells and target-cell membrane to induction of apoptosis. Cellular ＆ Molecular Immunology.     

肿瘤坏死因子引起的内皮细胞损伤与C－jun基因表达的变化

肿瘤坏死因子引起的内皮细胞损伤与Ｃ－ｊｕｎ基因表达的变化ＤａｍａｇｅｏｆＥｎｄｏｔｈｅｌｉａｌＣｅｌｌｓＩｎｄｕｃｅｄｂｙＴＮＦａｎｄＣｈａｎｇｅｏｆｃ－ｊｕｎＧｅｎｅＥｘｐｒｅｓｓｉｏｎ￥／／文／金惠铭，沙志一微血管壁通透性升高是创伤、感染、休克等...     

Cytomegalovirus-Induced Effector T Cells Cause Endothelial Cell Damage

Human cytomegalovirus (CMV) infection has been linked to inflammatory diseases that involve vascular endothelial cell damage, but definitive proof for a direct cytopathic effect of CMV in these diseases is lacking. CMV infection is associated with a strong increase in both CD4⁺ and CD8⁺ T cells with constitutive effector functions that can perpetuate systemic inflammation. We investigated whether CMV-induced immune responses could lead to endothelial damage in humans. We found that terminally differentiated effector CD4⁺ and CD8⁺ T cells, formed during primary CMV infection and maintained throughout latency, express high levels of CX3CR1 and CXCR3. The ligands of these receptors, fractalkine and IP-10, respectively, are expressed by activated endothelial cells. Peripheral blood mononuclear cells (PBMC) stimulated with CMV antigen produced soluble factors that stimulated endothelial cells to produce both chemokines. Finally, effector cells migrated in a fractalkine- and IP-10-dependent fashion to activated endothelial cells and induced apoptosis in endothelial cells that were stimulated by supernatant from CMV-activated PBMC. Our findings offer an explanation for the accumulation of highly differentiated T cells near to the endothelium in CMV-infected individuals that may result in endothelial damage.     

卡巴胆碱抑制肿瘤坏死因子所致微血管内皮细胞通透性增高

目的探讨卡巴胆碱对肿瘤坏死因子-α（tumor necrosis factor-α，TNF-α）诱导的增加微血管通透性的作用。方法采用FITC标记白蛋白漏出法、考马斯亮蓝染色法观察卡巴胆碱对TNF-α诱导微血管内皮细胞通透性，细胞形态和细胞骨架变化的影响。结果与对照组比较，TNF-α明显增加微血管内皮细胞通透性（P〈0．05），诱导细胞皱缩，细胞间隙增大和细胞骨架排列紊乱。给予卡巴胆碱可以明显抑制TNF-α诱导微血管内皮细胞通透性增加，并呈剂量依赖性，同时可以使细胞间隙明显减小，细胞骨架排列有序。结论卡巴胆碱可能通过抑制TNF-α对细胞骨架的损伤，进而抑制微血管通透性增加。     

高血脂对血细胞和血管内皮细胞的损伤

目的研究血清胆固醇 (cho)升高和氧化低密度脂蛋白 (OX -LDL)在血细胞和血管内皮细胞 (VEC)损伤中的作用。方法采用高胆固醇血症家兔模型研究血清cho对红细胞变形性 ,白细胞自发活化率及粘附分子 (CD11b/CD18)表达的影响。采用人脐静脉内皮细胞 (HUVEC)研究OX -LDL对VEC粘附分子 (ICAM -1、VCAM -1)和MCP-1表达的影响。结果动物模型的结果指出随着血清cho升高 ,红细胞变形性降低 ,白细胞SAR和CD11b/CD18表达增加。由HUVEC获得如下结果 :(1)培养的HUVEC能少量表达ICAM -1和MCP -1及蛋白 ;(2)OX -LDL可显著增强ICAM -1、MCP -1及蛋白表达。对VCAM -1表达无影响 ;(3)OX -LDL有细胞毒性 ,引起VEC形态异常。结论血清cho升高引起红细胞变形性降低 ,白细胞SAR升高 ,活化的白细胞通过释放超氧阴离子自由基 (O·2-)和蛋白酶 ,损伤VEC ,从而破坏内皮的完整性。因此 ,血清cho升高是AS和心、脑血管病的重要危险因素之一。     

Endothelial Cell Heterogeneity in Venules of Mouse Airways Induced by Polarized Inflammatory Stimulus

We sought to determine whether the changes in microvascular endothelial cells (EC) caused by a polarized chronic inflammatory stimulus depend on proximity to the stimulus. C3H mice were infected with Mycoplasma pulmonis, which attaches to the airway epithelium and creates a polarized inflammatory stimulus across the airway wall. At 1, 2, or 4 weeks, the tracheal vasculature was stained by perfusion of silver nitrate to mark EC borders or biotinylated Lycopersicon esculentum lectin to label the EC surface and adherent leukocytes. E-selectin immunoreactivity and EC proliferation were also localized. We found that the size, shape, and immunoreactivity for adhesion molecules on EC nearest the airway lumen (subepithelial EC) were different from those on the opposite surface of the same vessels. Subepithelial EC were smaller, more irregular in shape, had greater E-selectin immunoreactivity, and had twice as many adherent leukocytes. In contrast, proliferating EC were uniformly distributed around the vessel circumference. We conclude that the polarized stimulus created by M. pulmonis infection differentially changes the size, shape, and function of EC nearest the airway epithelium. This heterogeneity may result from a gradient of inflammatory mediators that triggers the influx of leukocytes into the airway lumen.     

重铬酸钾致鲫鱼肝细胞DNA损伤作用研究

目的建立鲫鱼肝细胞彗星试验方法,检测重铬酸钾致鱼肝细胞DNA损伤作用。方法制备鲫鱼原代肝细胞悬液,以0．5,0．25和0．1mM重铬酸钾染毒细胞1．5h,彗星试验检测细胞DNA损伤。结果重铬酸钾各浓度作用组细胞平均拖尾长度和拖尾细胞率存在剂量反应关系,且0．5和0．25mM作用组细胞平均拖尾长度与阴性对照组之间差异具有统计学意义（P〈0．05）。结论鲫鱼肝细胞彗星试验方法成功建立,重铬酸钾具有致鱼肝细胞DNA损伤作用。