鸟结核分枝杆菌感染巨噬细胞后的外泌体刺激巨噬细胞产生的细胞因子及其蛋白质表达改变

目的 探讨鸟结核分枝杆菌(M.avium)感染巨噬细胞后分泌的外泌体[(+)外泌体]刺激巨噬细胞后产生的分子免疫机制及其差异蛋白质成分研究.方法 冷冻高速离心法收集经鸟分枝结核杆菌感染及未感染的巨噬细胞上清中的外泌体,然后利用外泌体刺激巨噬细胞;ELISA方法检测经外泌体刺激巨噬细胞后细胞上清中IFN-γ、TNF-α的含量;流式细胞术从蛋白水平检测巨噬细胞受外泌体刺激后CD80、CD86蛋白表达情况;2-DE MALDI-TOF/TOF MS技术分析鉴定巨噬细胞受M.avium感染后分泌的外泌体中的差异蛋白.结果 IFN-γ、TNF-α在(+)外泌体刺激巨噬细胞后培养上清中含量增加;CD80、CD86蛋白在巨噬细胞受(+)外泌体刺激后表达上调.外泌体经2-DE MALDI TOF/TOF MS分析获得18个差异蛋白,且质谱成功鉴定12个.结论 (+)外泌体促进巨噬细胞TNF-α、IFN-γ的分泌从而增强巨噬细胞的炎症反应,并且可促进巨噬细胞CD80、CD86蛋白表达增强;筛选出差异蛋白的功能与细胞骨架结构、蛋白质合成与加工,炎症反应密切相关.     

阿糖胞苷上调耐药白血病细胞共刺激分子表达及其分子机制研究

目的研究阿糖胞苷（Ara-c）对耐药白血病细胞共刺激分子表达的影响，并探讨其分子机制。方法以流式细胞术检测K562和K562／A02细胞经Ara-C处理后CD80、CD86分子的表达，进而用RT-PCR方法检测CDS0、CD86mRNA表达以及NF-κB、IAP家族基因表达。结果经Ara-C处理后，K562和K562／A02细胞的CD80、CD86分子表达较对照组明显升高，并且能够下调NF-κB、Survivin、XIAP（X-linked inhibitor of apoptosis）基因表达，而cIAP1、cIAP2（cellular inhibitor of apoptosis-1，2）基因表达变化不明显。结论Ara-C可上调耐药白血病细胞共刺激分子CD80、CD86，相关基因NF-κB、IAP家族为参与其上调CD80和CD86分子的重要基因。     

Notch信号调控巨噬细胞激活分子机制的研究进展

巨噬细胞是机体抗感染免疫的主要效应细胞,是一类具有异质性的细胞亚群。因其解剖位置和功能表型上的差异,巨噬细胞可分为两类:组织定居巨噬细胞和炎性巨噬细胞。其中,炎性巨噬细胞的产生是巨噬细胞激活的表现形式,也是抵抗病原体入侵和重构组织稳态的一种免疫应答方式。巨噬细胞主要存在两种激活方式:经典激活和替代激活,激活后的巨噬细胞分别行使特定的功能。Notch信号通路可调控体内多种免疫细胞发育和功能,并通过多种分子机制调控巨噬细胞的激活。本文拟从巨噬细胞的类型、激活方式和Notch调控巨噬细胞激活的分子机制方面进行综述。     

加味宣肺透解剂对流感病毒感染小鼠细胞因子的影响

目的：观察加味宣肺透解剂（JXT）对流感病毒感染小鼠细胞因子的影响。方法：复制流感病毒鼠肺适应株（FM1）小鼠肺炎模型，以加味宣肺透解剂灌胃治疗。ELISA法检测感染后第5天血清中IL-2、TNF-α、IL-6、IFN-γ的含量，肺组织切片HE染色。结果：加味宣肺透解剂明显升高血清中IL-2、IFN-γ水平，降低TNF-α、IL-6水平，减轻肺组织病变。结论：调节细胞因子的分泌，可能是加味宣肺透解剂减轻病毒感染小鼠肺组织损伤的机制之一。     

结核分枝杆菌肝素结合血凝素在结核病免疫应答中的研究

目的 探讨结核分枝杆菌肝素结合血凝素(HBHA)的免疫应答作用及其在结核病诊断中的应用价值.方法 选取PPD(-)健康对照、PPD(+)潜伏感染者、肺结核患者,分离外周血单个核细胞,用大然HBHA刺激,培养4 d后收集细胞培养上清,ELISA方法检测上清中的IFN-γ.同时用ELISA方法检测各组血清中的HBHA特异的ISG型抗体.结果 HBHA刺激后3组产生的lFN-γ中位数分别为49.5 PS/ml、781.9 pg/ml、341.8 pg/ml,潜伏感染者产生的IFN-γ水平远高于健康对照,略高于肺结核患者.三组血清抗HBHA的IgG抗体浓度吸光度(A)的均值分别为0.212±0.066、0.224±0.076和0.285±0.078.肺结核患者的HBHA特异的IgG抗体远高于健康对照及潜伏感染者.结论 HBHA有较好的免疫原性,可以刺激潜伏感染者产生高水平的IFN-γ,HBHA特异的IFN-γ释放反应有利于鉴别潜伏感染者.HBHA的抗体水平在结核病的诊断中有一定的辅助应用价值.     

microRNA调控结核分枝杆菌感染巨噬细胞凋亡的研究进展

细胞凋亡对于机体抑制或清除胞内结核分枝杆菌( Mycobacterium tuberculosis, Mtb)尤为重要, Mtb感染巨噬细胞后,往往会诱导机体启动一系列机制调控巨噬细胞凋亡。在 Mtb感染的巨噬细胞内存在差异表达的microRNAs (miRNAs),miRNA可直接结合凋...     

体外单核巨噬细胞诱生IFN-α的因素分析

观察了Ｍ－ＣＳＦ预处理、ＩＦＮ－γ预处理、长程培养及新城疫病毒（ｎｅｗ－ｃａｓｔｌｅｄｉｓｅａｓｅｖｉｒｕｓ,ＮＤＶ）刺激４个因素对正常人外周血单核细胞体外产生ＩＦＮ－α水平的影响,采用生物活性法检测ＩＦＮ－α。结果表明：单独使用Ｍ－ＣＳＦ不能诱生ＩＦＮ－α;单独使用ＩＦＮ－γ或单独使用ＮＤＶ均只诱生较低水平ＩＦＮ－α,只有Ｍ－ＣＳＦ＋ＩＦＮ－γ＋ＮＤＶ或ＩＦＮ－γ＋ＮＤＶ联合使用方可诱生较高水平的ＩＦＮ－α,并且发现Ｍο、－Ｍφ长程培养也是向高产发展的一个重要因素。结论：人血Ｍο、－Ｍφ在适当体外培养条件下,可以诱发较高水平的ＩＦＮ－α     

结核分枝杆菌Rv1626的原核表达及其免疫功能研究

结核分枝杆菌;Rv1626;原核表达;免疫原性;结核病     

灭活草分枝杆菌雾化吸入对过敏性支气管哮喘患者外周血及诱导痰中B7分子的影响

探讨单核细胞B7分子在雾化吸入灭活草分枝杆菌防治过敏性支气管哮喘中的作用。正常对照组15例(A组),27例尘螨过敏性轻、中度持续期支气管哮喘患者随机分为常规治疗组(B组,13例)和雾化吸入组(C组,14例),B组吸入沙美特罗替卡松粉吸入剂;C组雾化吸入灭活草分枝杆菌,两组患者分别在治疗前、治疗第6天、第31天检测肺通气功能、流式细胞术检测外周血和诱导痰中CD80+、CD86+单核细胞占CD14+单核细胞百分率。结果显示B、C两组外周血CD80表达率均高于A组(P值均0.01)、第31天比治疗前降低(P值均0.01);CD86表达率B、C组与A组无统计学意义,B、C两组治疗前后比较无统计学意义;B、C两组诱导痰中CD80、CD86表达率均比A组高(P值均0.01),与治疗前相比,第6天CD80、CD86表达率C组降低(P值均0.05);第31天CD80、CD86表达率B、C两组均显著降低(P值均0.05);哮喘患者外周血及诱导痰中单核细胞CD80、CD86表达率与FEV1、PEF呈中度负相关(P值均0.01)。由此证明过敏性支气管哮喘患者外周血及诱导痰中B7分子表达增高,且与肺通气功能呈负相关;雾化吸入灭活草分枝杆菌可通过下调B7分子从而达到对过敏性支气管哮喘的防治。     

结核分枝杆菌与巨噬细胞的相互作用

结核分枝杆菌(Mtb)是人类一种较难克服的致病菌.巨噬细胞(Mφ)作为机体固有免疫的重要组成部分在抵抗外来病原微生物中发挥着至关重要的作用.它们之间的相互作用一直被研究者所重视,近年来随着多重耐药菌株的出现以及结核病的死灰复燃使得对其更加受到研究者的重视.因而,深入了解Mφ抵抗Mtb的侵害及Mtb躲避Mφ杀伤的各种机制可以寻找防治结核病的新的治疗靶点.     

Differential mechanisms of intracellular killing of Mycobacterium avium and Listeria monocytogenes by activated human and murine macrophages. The role of nitric oxide.

Murine peritoneal macrophages activated with interferon-gamma (IFN-gamma) produce large quantities of nitric oxide and are efficient in the killing of certain intracellular pathogens. To examine the role of this mechanism in the killing of Mycobacterium avium by murine and human macrophages, we infected mouse peritoneal macrophages and human monocyte-derived macrophages with M. avium and Listeria monocytogenes and stimulated the cells with recombinant tumour necrosis factor (TNF), granulocyte-macrophage colony-stimulating factor (GM-CSF) or IFN-gamma, in the presence or absence of N-monomethyl-L-arginine (NMA) or arginase. Neither competitive inhibition with NMA nor depletion of arginine by arginase had any effect on the inhibition of growth/intracellular killing of M. avium by activated human and murine macrophages. In contrast, activation of murine but not human macrophages infected with L. monocytogenes by IFN-gamma was significantly inhibited by the addition of NMA/arginase. Furthermore, murine macrophages produced large concentrations of nitric oxide following stimulation with recombinant cytokines, although no significant increase of nitric oxide production was observed with human monocyte-derived macrophages.     

The effect of early and late treatment with the tyrphostin AG-556 on the progression of experimental autoimmune myocarditis

Experimental autoimmune myocarditis (EAM) in rats is a T-cell-mediated disorder; the involvement of TNF-alpha in this disorder has been demonstrated. EAM represents a model for human autoimmune myocarditis, a condition for which no optimal treatment is currently available. Tyrphostins AG-126 and AG-556 were previously shown to reduce TNF-alpha production and its end-organ cytotoxicity, thus proving beneficial in animal models of septic shock and experimental autoimmune encephalomyelitis. To study the effects of AG-126 and AG-556 on EAM, we induced the disorder in male Lewis rats through immunization against myosin and subsequently treated the rats with both agents or the control DMSO both before and after the appearance of myocardial inflammation. AG-556 administered daily for 21 days from the day of EAM induction, significantly reduced the severity of myocarditis. Similarly, AG-556 administered for an additional 10 days after myosin immunization (when signs of inflammation are already present) attenuated the progression of myocarditis, though AG-126 did not. TNF-alpha and IFN-gamma production by in vitro sensitized splenocytes from AG-556-treated rats was significantly diminished as compared with control cells from EAM animals. Thus, AG-556 may represent a novel strategy of ameliorating the progression of myocarditis without non-selectively compromising the immune system.     

慢性 HCV 感染者外周血中 CD56＋T 细胞频数、表型和体外细胞毒功能研究

目的探讨慢性HCV感染者外周血中CD56＋T细胞的频数、表型和体外细胞毒功能特征。方法采用流式细胞术检测33例慢性HCV感染者及21例健康对照者外周血CD56＋T细胞的频数和细胞表面活化性受体NKG2C、CD16、NKp46和抑制性受体CD158a、NKG2A的表达水平;检测体外未刺激及K562细胞刺激作用下CD 56＋T细胞毒效应（ CD107a）和细胞因子分泌水平（ IFN-γ和TNF-α）,并分析上述3种CD56＋T细胞功能指标之间的关联性。结果与健康对照相比,慢性HCV感染者外周血中CD56＋T细胞在淋巴细胞中的比例明显降低（ P＝00．18）。 CD56＋T细胞表面的活化性受体 NKG2C（P＝0．015）、CD16（P＝0．036）、NKp46（P＝0．001）均有不同程度降低,而抑制性受体CD158a、NKG2A未发现有统计学意义的差异（P＞0．05）。体外未刺激情况下,慢性HCV感染者CD56＋T细胞分泌细胞因子IFN-γ和TNF -α均显著弱于健康对照组（P ＜0．0001）;在K562细胞刺激作用下,慢性HCV感染者 CD56＋T细胞CD107 a水平及分泌细胞因子IFN-γ和TNF-α均呈显著降低趋势（ P＜0．0001）,且3种功能指标表达水平密切关联（r＞0．80, P＜0．0001）。结论慢性HCV感染者CD56＋T 细胞频数降低,细胞毒能力和重要细胞因子分泌能力均明显减弱。该结果提示显著受损的CD56＋T细胞功能可能与HCV慢性持续性感染有关。     

Isolation and phenotypic characterization of colonic macrophages

Macrophages play an important role in the intestinal mucosal immune system. However, they are a poorly defined cell population. We therefore determined their phenotype in normal colonic mucosa. Macrophages were isolated from colonic biopsies and surgical specimens by collagenase digestion. Colonic macrophages were positively sorted by anti-CD33 magnetic beads. Flow cytometric triple fluorescence analysis was applied to study CD14, CD16, CD33, CD44, CD11b, CD11c, CD64, HLA-DR, CD80, CD86 and CD3/CD19 expression. CD33 was evaluated as a positive marker for intestinal macrophages. CD33⁺ cells isolated from normal colonic mucosa showed co-expression of the established intracellular macrophage marker CD68 in FACS analysis. CD33⁺ cells were capable of phagocytosis. Isolation of this cell population by magnetic anti-CD33 beads and culture resulted in a 4.2–40-fold increase in IL-1β and 4.5–44-fold increase in tumour necrosis factor-alpha (TNF-α) secretion compared with unsorted lamina propria mononuclear cells (LPMC). Of the CD33⁺ cells, 90.9 ± 6.9% (mean ± s.d.) were CD44⁺. However, macrophages from colonic mucosa showed only a low expression of CD14 (10.5 ± 3.8%), CD16 (10.1 ± 3.9%), HLA-DR (27.3 ± 9.2%), CD11b (17.4 ± 6.8%), CD11c (17.8 ± 10.4%). Furthermore, expression of CD80 (9.2 ± 4.2%) and CD86 (15.1 ± 7.3%) was low, suggesting a low ability of normal intestinal macrophages to activate T cells and T cell-mediated immune responses. We conclude that CD33 is useful for the isolation and flow cytometric characterization of colonic macrophages. These cells exhibit a single phenotype in normal mucosa (CD33⁺⁺, CD44⁺⁺, CD14^?, CD16^?, CD11b^?, CD11c^?, HLA-DR^low, CD80^?, CD86^?) lacking lipopolysaccharide (LPS) receptor and costimulatory molecules.     

Activity of HMR3004 against Mycobacterium avium complex in vitro, in human macrophages and in beige mice

Objective: To evaluate in vitro, in a cultured macrophage system and in beige mice, the potential therapeutic activity of HMR3004, a new ketolide, against organisms of the Mycobacterium avium complex (MAC).
Methods: The activity of HMR 3004 against MAC was evaluated in vitro (BACTEC) method) in the human macrophage system and in the beige mouse model.
Results: HMR3004 was inhibitory for 50% of 24 MAC strains at 8 mg/L and for 90% of the MAC strains at 16 mg/L by the radiometric macrobroth dilution method. The activity in vitro was improved if the MIC determination was carried out at pH 7.2 instead of pH 6.8. When tested in the macrophage system against three strains of MAC, HMR3004 showed inhibitory activity when used at 0.25 mg/L compared with untreated controls. Administration of HMR3004 to beige mice infected with MAC 101 strain caused significant reduction in the number of bacteria in the blood, liver and spleen. The reductions were dose-related, with 200 mg/kg per day for 4 weeks being more effective than 100 mg/kg per day or 50 mg/kg per day (although a dose-dependent relationship was not observed in mortality).
Conclusion: The ketolide HMR3004 has been shown to be active against MAC, and further assessment of both the therapeutic and prophylactic activity are warranted.     

Regulation of expression of major histocompatibility antigens by bovine macrophages infected with Mycobacterium avium subsp. paratuberculosis or Mycobacterium avium subsp. avium

Mycobacterium avium subsp. paratuberculosis and Mycobacterium avium subsp. avium are antigenically and genetically very similar organisms; however, they differ markedly in their virulence for cattle. We evaluated the capacity of bovine macrophages infected with M. avium subsp. paratuberculosis or M. avium subsp. avium to express major histocompatibility complex (MHC) class I and class II antigens on their surface and to interact with primed autologous lymphocytes. Our results indicate that infection of bovine macrophages with M. avium subsp. paratuberculosis promoted the downregulation of MHC class I and class II molecules on the macrophage surface within 24 and 12 h, respectively. Alternatively, MHC class II expression by M. avium subsp. avium-infected macrophages was not detected until 24 h after infection, and the magnitude of the decrease was smaller. Decreased MHC class I expression by M. avium subsp. avium-infected macrophages was not detected. Unlike M. avium subsp. paratuberculosis-infected macrophages, M. avium subsp. avium-infected macrophages upregulated MHC class I and class II expression after activation by gamma interferon or tumor necrosis factor alpha. Further, M. avium subsp. avium-infected macrophages were lysed by primed autologous lymphocytes, whereas M. avium subsp. paratuberculosis-infected macrophages were not. Overall, the results support the hypothesis that the difference in the virulence of M. avium subsp. paratuberculosis and M. avium subsp. avium for cattle is dependent on a difference in the capacity of the organisms to suppress mycobacterial antigen presentation to T lymphocytes.     

Dynamics of immune effector mechanisms during infection with Mycobacterium avium in C57BL/6 mice

Opportunistic infections with non‐tuberculous mycobacteria such as Mycobacterium avium are receiving renewed attention because of increased incidence and difficulties in treatment. As for other mycobacterial infections, a still poorly understood collaboration of different immune effector mechanisms is required to confer protective immunity. Here we have characterized the interplay of innate and adaptive immune effector mechanisms contributing to containment in a mouse infection model using virulent M. avium strain 104 in C57BL/6 mice. M. avium caused chronic infection in mice, as shown by sustained organ bacterial load. In the liver, bacteria were contained in granuloma‐like structures that could be defined morphologically by expression of the antibacterial innate effector protein Lipocalin 2 in the adjoining hepatocytes and infiltrating neutrophils, possibly contributing to containment. Circulatory anti‐mycobacterial antibodies steadily increased throughout infection and were primarily of the IgM isotype. Highest levels of interferon‐γ were found in infected liver, spleen and serum of mice approximately 2 weeks post infection and coincided with a halt in organ bacterial growth. In contrast, expression of tumour necrosis factor was surprisingly low in spleen compared with liver. We did not detect interleukin‐17 in infected organs or M. avium‐specific T helper 17 cells, suggesting a minor role for T helper 17 cells in this model. A transient and relative decrease in regulatory T cell numbers was seen in spleens. This detailed characterization of M. avium infection in C57BL/6 mice may provide a basis for future studies aimed at gaining better insight into mechanisms leading to containment of infections with non‐tuberculous mycobacteria.     

Relationship of heat shock protein 25 with reactive macrophages in thioacetamide-induced rat liver injury

Heat shock protein 25 (Hsp25), which has anti-inflammatory activity, was examined for the relationship of its expression to macrophage appearance in thioacetoamide (TAA)-induced rat acute hepatic lesions. TAA-induced lesions, consisting of hepatocyte coagulation necrosis and reactive macrophages, developed in the centrilobular areas. Macrophages immuno-reacting to ED1 (CD68; exudative macrophages) were mainly seen within the lesions, whereas macrophages reacting to ED2 (CD163; resident macrophages and Kupffer cells), which have abundant cytoplasm, appeared mainly in the periphery of the lesions. Hsp25-immunopositivity was seen in hepatocytes around the lesions in relation to ED1- and ED2-positive macrophages in and around the centrilobular lesions, respectively. Because macrophages appearing in early stages of hepatic lesions produce various pro-inflammatory factors, mRNA expressions of tumor necrosis factor-α (TNF-α), monocyte chemoattractant factor-1 (MCP-1) and osteopontin (OPN) were examined in relation to Hsp25 mRNA expression. Hsp25 mRNA expression generally was correlated with TNF-α, MCP-1 and OPN expressions, suggesting their direct or indirect association with Hsp25 expression. Thus, Hsp25 might have a cytoprotection function against macrophages appearing in hepatic lesions, and factors produced by macrophages in the very early stages of hepatic lesions may influence Hsp25 expression. Hsp25 expression should be useful as an index of anti-inflammatory action for evaluation of hepatotoxicants in vivo.     

人偏肺病毒感染人肺上皮细胞后Toll样受体的表达及其功能

目的 观察人偏肺病毒(human metapneumoviras)感染人肺上皮细胞后Toll样受体(TLR)表达变化及其信号通路的功能,探讨hMPV诱导气道炎症的部分机制.方法 hMPV感染体外培养的人肺上皮细胞株A549,检测病毒在A549细胞中的生长曲线,并通过RT-PCR,real-timeRT-PCR方法检测细胞TLR mRNA的表达,ELISA检测细胞培养上清IFN-α及TNF-α的表达.结果 (1)hMPV可在A549细胞中复制,感染后3 d达高峰10~(5.2)TCID_(50)/ml.(2)RT-PCR结果提示:hMPV感染A549细胞6 h后大部分TLR的表达均上调.(3)定量PCR结果提示:hMPV感染A549细胞后TLR3-4、TLR7-9的表达增高,且有时间依赖性,而紫外灭活的hMPV刺激细胞后TLR表达无明显变化.(4)ELISA结果提示hMPV感染后24 h,IFN-α及TNF-α的表达均明显升高.结论 人偏肺病毒感染A549细胞后可上调TLR表达,其诱导的炎性反应与部分TLR介导的信号转导途径有关.     

IL-18在实验性暴发型肝衰竭发病机制中的作用

为探讨IL 18在暴发型肝衰竭发生中的表达变化及对其他细胞因子的调控作用。采用D 氨基半乳糖 (D Gal) 90 0mg/kg与脂多糖 (LPS ) 10 μg/kg诱导BALB/c小鼠暴发型肝衰竭 ,检测不同时间点血清转氨酶 (ALT、AST )和肝组织病理、DNA梯形条带 ,评估肝损伤情况 ;用半定量RT PCR和相应的分析软件分析不同时间点肝组织中IL 18mRNA、TNF αmRNA和IFN γmRNA表达及ELISA方法检测血浆IL 18、TNF α和IFN γ的蛋白表达。结果 :D Gal/LPS给予后 4h血清转氨酶明显升高 ,7h小鼠开始死亡 ,10h死亡率达 80 %。肝组织病理学检查发现 ,5h肝窦扩张、炎性细胞浸润、枯否细胞增生 ;7h肝细胞大量凋亡、坏死或肝组织出现大量出血性坏死 ;5h电镜示肝细胞核仁碎裂、线粒体肿胀或空泡变性 ;7h核仁边聚 ,呈半月型 ,表现为典型的凋亡形态学变化 ,线粒体大部分空泡变性。DNA电泳显示 5h始出现梯形条带。正常小鼠肝组织IL 18mRNA有少量表达 ,TNF αmRNA、IFN γmRNA微量表达。给药后 ,三者的mRNA分别在 1h、 2h、 3h达高峰 ,血浆中TNF α、IFN γ水平与其mRNA变化显著正相关 (rTNF α=0 4 3,P =0 0 1;rIFN γ=0 6 9,P <0 0 0 1) ,而血浆IL 18与其mRNA表达无明显相关 (r= 0 12 ,P =0 2 5 )。本实验诱导的暴发型肝衰竭模型中 ,肝细?