MS-8209, a new amphotericin B derivative, provides enhanced efficacy in delaying hamster scrapie.

To test the efficacy of a new amphotericin B derivative, MS-8209, in delaying scrapie, hamsters were infected intracerebrally with the 263K scrapie agent and treated with MS-8209 either early in the course of the disease or continuously. The results show that (i) all treatments lengthened the incubation period of hamster scrapie, (ii) continuous treatment with MS-8209 doubled the length of the incubation period compared with that observed in infected, untreated animals, and (iii) all treatments delayed the accumulation of a proteinase-resistant prion protein and glial fibrillary acidic protein in the brain. These findings suggest that MS-8209 is a powerful tool for investigating the pathogenesis of transmissible subacute spongiform encephalopathies.     

Activity of MS-8209, a nonester amphotericin B derivative, in treatment of experimental systemic mycoses.

The in vitro and in vivo toxicities and activities of MS-8209, a new hydrosoluble amphotericin B (deoxycholate-amphotericin B [D-AmB]; Fungizone) derivative, were studied. In vitro, MS-8209 was less toxic than AmB against renal tubular cells in primary culture and less active against Candida albicans and Cryptococcus neoformans. However, at 10-fold the AmB concentration, MS-8209 in vitro antifungal activity paralleled that of AmB. Fifty-percent lethal doses of MS-8209 and D-AmB in OF1 noninfected mice were 26 and 2.3 mg/kg, respectively. Therapeutic efficacy of MS-8209 was assessed in murine candidiasis, cryptococcosis, and aspergillosis. In each model of infection, we determined the maximum tolerated dosages of MS-8209 and D-AmB, i.e., the dosage inducing less than 15% mortality due to toxicity; the efficacies of MS-8209 and D-AmB at their respective maximum tolerated dosages were compared. In candidiasis, MS-8209 (15 mg/kg) significantly increased the survival time compared with D-AmB (0.5 mg/kg). Both compounds were equally effective at reducing CFU counts in the kidney. MS-8209 was the most effective agent for increasing the survival time in cryptococcal meningoencephalitis and for reducing CFU counts in spleen, brain, and lung during both cryptococcal pneumonia and meningoencephalitis. In aspergillosis, MS-8209 and D-AmB similarly prolonged the survival of treated mice compared with controls. These results show that when MS-8209 and D-AmB were used at the maximum tolerated dosage, MS-8209 was as effective as or more effective than D-AmB for the treatment of systemic mycoses. These findings warrant further experiments to study the pharmacokinetic properties and toxicity of MS-8209 under conditions of chronic administration.     

Reduction of no synthase expression and tumor necrosis factor alpha production in macrophages by amphotericin B lipid carriers

The present study compared the abilities of different lipid carriers of amphotericin B (AMB) to activate murine peritoneal macrophages, as assessed by their capacities to produce nitric oxide (NO) and tumor necrosis factor alpha (TNF-alpha). Although AMB alone did not induce NO production, synergy was observed with gamma interferon but not with lipopolysaccharide. This synergy could not be explained by the mobilization of the nuclear activation factor NF-kappaB by AMB. On the other hand, AMB induced TNF-alpha production without a costimulator and no synergy was observed. Anti-TNF-alpha antibodies did not influence NO production, and an inhibitor of NO synthase did not affect TNF-alpha production, indicating that the production of one of these effector molecules was independent of that of the other. The incorporation of AMB into lipid carriers reduced NO and TNF-alpha production with all formulations but more so with liposomes than with lipid complexes. NO production was correlated with the induction of NO synthase II, revealed by Western blotting. The extent of association of AMB with macrophages depended on the formulation, especially on the AMB/lipids ratio: the higher the ratio was, the greater the AMB association with macrophages. However, there was no clear correlation between AMB association with macrophages, whether internalized or bound to the membrane, and immunostimulating effects. These results may explain the reduced toxicities of lipid-based formulations of AMB.     

Effect of tumor necrosis factor alpha on mitogen-activated human B cells

In this study we demonstrate that the monocyte/macrophage product, tumor necrosis factor alpha (TNF-alpha), has significant in vitro effects of B cell function. It costimulated with anti-mu in the induction of B cell DNA synthesis, and it prolonged the DNA synthesis initiated in B cell cultures stimulated with the human B cell mitogen, Staphylococcus aureus Cowan strain I (SAC). The addition of either IL-1 or IFN-gamma to TNF-alpha resulted in a substantial further increase in DNA synthesis. The addition of TNF-alpha to IL-2, a known inducer of SAC-activated B cell Ig secretion, resulted in a twofold enhancement in the amount of IL-2 stimulated B cell Ig secretion. Receptor binding studies with 125I-TNF-alpha demonstrate a marked increase in TNF-alpha binding sites after B cell activation (approximately 6,000 sites per cell, with an apparent Kd of 2.0 X 10(-10) M). Thus, TNF-alpha may be an important factor in human B cell function and is likely to interact with other T cell and monocyte derived cytokines in the regulation of human B cell proliferation and Ig production.     

Preincubation of Candida albicans strains with amphotericin B reduces tumor necrosis factor alpha and interleukin-6 release by human monocytes.

The release of tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) by human monocytes stimulated with whole heat-killed Candida albicans CA3 (a clinical isolate) and CA2 (a germ tube-negative mutant) either treated or not treated with amphotericin B was investigated. The optimal release of the cytokines was observed at 24 h of incubation of the yeasts with the monocytes for both TNF-alpha and IL-6. The levels ranged from 10,500 to 19,000 U/ml for TNF-alpha and from 350 to 460 pg/ml for IL-6. Germ tube-negative mutant CA2 induced the release of TNF-alpha at levels significantly (P < 0.05) lower than those induced by clinical isolate CA3, while no major differences were observed between the two strains with regard to their capacity to induce the release of IL-6. In all instances, preincubation of the yeasts with a sublethal concentration of amphotericin significantly reduced cytokine production. These results suggest that drug-induced alterations of fungal outer structures may affect the interactions between the yeasts and the monocytes, resulting in a reduced level of secretion of cytokines.     

Adeno-associated virus production of soluble tumor necrosis factor receptor neutralizes tumor necrosis factor alpha and reduces arthritis

The major limitation of adenovirus is its association with induction of an inflammatory response and relatively short-term production of the gene therapy transgene product. Adeno-associated virus (AAV) is a 4.68-kb single-strand DNA virus that contains ITRs for viral replication and a packaging signal, and also has been engineered to contain therapeutic genes up to 5 kb in length. Transduction of recombinant AAV (rAAV) results in low inflammatory response and long-term expression. We have cloned a low-immunogenic form of human sTNFRI (sTNFRI2.6D) into AAV (rAAVsTNFRI). This vector was analyzed for its ability to transfect and neutralize the effect of TNF-alpha on primary rheumatoid arthritis synovial fibroblast (RASFs). The rAAVsTNFRI was transduced into the cells at 1.8 x 10(1), 1.8 x 10(2), and 1.8 x 10(3) viral particles per cell. There was greater than 90% neutralization of TNF-alpha at 1.8 x 10(3) viral particles/cell. There was a significant decrease in the synovial cell hyperplasia and cartilage and bone destruction in human TNF-alpha transgenic mice treated intraarticularly with rAAVsTNFRI. These results indicate that the low-immunogenic and long-term expressing vector, rAAVsTNFRI, can be used to deliver the soluble TNF-alpha in vitro and in vivo and effectively reduce the severity of arthritis.     

Failure of dideoxynucleosides to inhibit human immunodeficiency virus replication in cultured human macrophages

Primary human monocyte-derived macrophages (MDM) were shown to have diminished deoxynucleoside kinase activities compared to T lymphoblasts, and a reduced ability to phosphorylate dideoxynucleosides with anti-human immunodeficiency virus (HIV) activity. These drugs, azidothymidine (AZT), dideoxycytidine (ddC), and dideoxyadenosine (ddA), which are potent anti-HIV agents in CD4 lymphocytes, did not inhibit HIV replication in MDM, even at concentrations of 100 microM. This drug concentration of AZT is approximately 100-fold higher than the levels attained in the serum of treated patients and the levels required to inhibit HIV replication in lymphocytes. These observations may explain the failure of AZT therapy to clear viremia, consistent with the presence of a drug-resistant reservoir of infected cells in vivo. New therapeutic approaches to inhibit the replication of HIV in MDM may be needed.     

早期生长反应基因1对巨噬细胞分泌肿瘤坏死因子α的影响

背景：体内外研究已证实肺巨噬细胞合成和分泌肿瘤坏死因子α 等参与肺组织局部损伤和炎症反应，但具体发生机制仍不明确。 目的：观察核转录因子早期生长反应基因1对巨噬细胞分泌肿瘤坏死因子α的影响。设计、时间及地点：随机分组设计，于2004-06／2006—12在湘雅医学院病理学系完成。材料：标准石英粉尘（SiO2）为Sigma公司产品：早期生长反应基因1抗体为Santa Cruz公司产品：小鼠巨噬细胞系RAW264．7购自中科院上海生物细胞研究所细胞库。方法：实验将巨噬细胞分为正常对照组、二氧化硅刺激组、Egr-1＋二氧化硅组和IgG＋二氧化硅组，前两组加无血清培养基，后两组分别加入5，10，20mg／L不同浓度的Egr-1和IgG抗体干预。 主要观察指标：酶联免疫吸附实验检测各组细胞上清中肿瘤坏死因子α蛋白的水平；反转录-聚合酶链反应检测细胞内肿瘤坏死因子amRNA的表达。结果：①与二氧化硅刺激组相比，不同浓度Egr-1＋二氧化硅组细胞上清中肿瘤坏死因子α蛋白水平均下降（P〈0．01），且10mg／L组与5，20mg／L组相比，差异有显著性意义（P〈0．05）。不同浓度IgG＋二氧化硅组相比，上清液中肿瘤坏死因子α蛋白水平差异无显著性意义（F=1．008，P=0．438）。②二氧化硅刺激组肿瘤坏死因子ⅡmRNA表达高于正常对照组（P〈0．01），而Egr-1＋二氧化硅组mRNA表达低于二氧化硅刺激组和IgG＋二氧化硅组（P〈0．01）。结论：二氧化硅致巨噬细胞分泌肿瘤坏死因子α增加可能通过激活核转录因子早期生长反应基因1介导的信号通路而实现。     

Effects of RP 55778, a tumor necrosis factor alpha synthesis inhibitor, on antiviral activity of dideoxynucleosides.

Tumor necrosis factor alpha (TNF-alpha) is overexpressed during human immunodeficiency virus (HIV) infection. RP 55778, a TNF-alpha synthesis inhibitor, decreases HIV replication in monocytes/macrophages. Therapeutic use of RP 55778 in vivo, like that of other biological response modifiers, would theoretically require association with dideoxynucleosides. We have evaluated here the combinatory effects of zidovudine (AZT) or dideoxyinosine (ddI) and RP 55778. This TNF-alpha inhibitor antagonizes the antiviral effects of both dideoxynucleosides, especially AZT. The more favorable anti-HIV activity of ddI in resting cells may explain these unequal degrees of antagonism.     

山莨菪碱干预急性肺损伤家兔肺泡巨噬细胞中核因子κB和肿瘤坏死因子αmRNA的表达

目的：观察山莨菪碱对创伤性急性肺损伤家兔肺泡巨噬细胞中核因子κB活化和下游基因肿瘤坏死因子αmRNA表达的影响。 方法：实验于2004-03／2005-02在解放军第四军医大学西京医院检验科临床分子生物学实验中心完成。将健康成年家兔72只抽签法随机分为3组（n=24）：①山莨菪碱组：于撞击台上行胸壁撞击（冲击速度5．7m／s，力75．8N／cm^2，冲撞能量约204J）后，立即静脉注射大肠杆菌脂多糖50μg／kg，建立创伤性急性肺损伤模型，造模后立即予以山莨菪碱2mg／kg静注，随后以1mg／（kg&;#183;h）静脉维持。②急性肺损伤组：造模同山莨菪碱组，造模后以等量生理盐水静注和维持。③正常对照组：不做胸壁撞击，静注等量生理盐水代替脂多糖，其余处理同急性肺损伤组。各组动物分别于模型建立后1，2，3，4h放血处死6只，留取支气管肺泡灌洗液，分离肺泡巨噬细胞，分别用凝胶电泳迁移率改变分析法和半定量反转录-聚合酶链反应法检测肺泡巨噬细胞中核因子κB的活性变化及肿瘤坏死因子αmRNA的表达水平，以相对吸光度表示。 结果：67只兔进入结果分析。①核因子κB的活性：急性肺损伤组于模型建立后1-4h内均明显高于正常对照组（P〈0．01），在2h达到高峰，其相对吸光度值，是同期正常对照组的8倍；山莨菪碱组高于正常对照组（P〈0．01），显著低于急性肺损伤组（P〈0．01），其中2h降幅最大，达30．19％。②肿瘤坏死因子αmRNA的表达水平：急性肺损伤组在模型建立后1h其表达即开始上升，两三小时达到高峰，3h最高，其相对吸光度值，是同期正常对照组的5倍，4h其表达较前有所下降，但仍明显高于正常对照组（P〈0．01）；山莨菪碱组各时间的表达显著低于急性肺损伤组（P〈0．01，0．05），最大降幅出现在2h，达34．48％。 结论：①机体遭受创伤及脂多糖刺激后，肺泡巨噬细胞被激活导致核因子κB的活化是肺泡巨噬细胞大量释放肿瘤坏死因子α等前炎细胞因子的关键环节。②山莨菪碱可能是通过抑制肺泡巨噬细胞核中核因子κB活性，在基因转录水平抑制其介导的一系列细胞因子和炎症递质的表达（肿瘤坏死因子α等），阻断细胞因子和炎症递质的失控性释放来实现对急性肺损伤的治疗作用的。     

山莨菪碱干预急性肺损伤家兔肺泡巨噬细胞中核因子κB和肿瘤坏死因子αmRNA的表达

目的:观察山莨菪碱对创伤性急性肺损伤家兔肺泡巨噬细胞中核因子κB活化和下游基因肿瘤坏死因子αmRNA表达的影响。方法:实验于2004-03/2005-02在解放军第四军医大学西京医院检验科临床分子生物学实验中心完成。将健康成年家兔72只抽签法随机分为3组(n=24):①山莨菪碱组:于撞击台上行胸壁撞击(冲击速度5.7m/s,力75.8N/cm2,冲撞能量约204J)后,立即静脉注射大肠杆菌脂多糖50μg/kg,建立创伤性急性肺损伤模型,造模后立即予以山莨菪碱2mg/kg静注,随后以1mg/(kg·h)静脉维持。②急性肺损伤组:造模同山莨菪碱组,造模后以等量生理盐水静注和维持。③正常对照组:不做胸壁撞击,静注等量生理盐水代替脂多糖,其余处理同急性肺损伤组。各组动物分别于模型建立后1,2,3,4h放血处死6只,留取支气管肺泡灌洗液,分离肺泡巨噬细胞,分别用凝胶电泳迁移率改变分析法和半定量反转录-聚合酶链反应法检测肺泡巨噬细胞中核因子κB的活性变化及肿瘤坏死因子αmRNA的表达水平,以相对吸光度表示。结果:67只兔进入结果分析。①核因子κB的活性:急性肺损伤组于模型建立后1～4h内均明显高于正常对照组(P<0.01),在2h达到高峰,其相对吸光度值,是同期正常对照组的8倍;山莨菪碱组高于正常对照组(P<0.01),显著低于急性肺损伤组(P<0.01),其中2h降幅最大,达30.19%。②肿瘤坏死因子αmRNA的表达水平:急性肺损伤组在模型建立后1h其表达即开始上升,两三小时达到高峰,3h最高,其相对吸光度值,是同期正常对照组的5倍,4h其表达较前有所下降,但仍明显高于正常对照组(P<0.01);山莨菪碱组各时间的表达显著低于急性肺损伤组(P<0.01,0.05),最大降幅出现在2h,达34.48%。结论:①机体遭受创伤及脂多糖刺激后,肺泡巨噬细胞被激活导致核因子κB的活化是肺泡巨噬细胞大量释放肿瘤坏死因子α等前炎细胞因子的关键环节。②山莨菪碱可能是通过抑制肺泡巨噬细胞核中核因子κB活性,在基因转录水平抑制其介导的一系列细胞因子和炎症递质的表达(肿瘤坏死因子α等),阻断细胞因子和炎症递质的失控性释放来实现对急性肺损伤的治疗作用的。     

PMS-601, a new platelet-activating factor receptor antagonist that inhibits human immunodeficiency virus replication and potentiates zidovudine activity in macrophages

We assessed the anti-human immunodeficiency virus (anti-HIV) activity in vitro of new platelet-activating factor (PAF) receptor antagonists, as PAF and viral replication are thought to be involved in HIV neuropathogenesis. We found that PMS-601 inhibited proinflammatory cytokine synthesis and HIV replication in macrophages and potentiated the antiretroviral activity of zidovudine. These results suggest that PMS-601 is of potential value as an adjuvant treatment for HIV infection.     

Potential new anti-human immunodeficiency virus type 1 compounds depress virus replication in cultured human macrophages

We report that the amiloride analogues 5-(N,N-hexamethylene)amiloride and 5-(N,N-dimethyl)amiloride inhibit, at micromolar concentrations, the replication of human immunodeficiency virus type 1 (HIV-1) in cultured human blood monocyte-derived macrophages. These compounds also inhibit the in vitro activities of the HIV-1 Vpu protein and might represent lead compounds for a new class of anti-HIV-1 drugs.     

Augmentation of murine tumor necrosis factor production by amphotericin B in vitro and in vivo.

Murine peritoneal macrophages were preincubated with amphotericin B (AMPH) and were then stimulated with bacterial lipopolysaccharide or streptococcal preparation (OK432). These macrophages produced a large amount of tumor necrosis factor. When administered to mice, the priming activity of amphotericin B for tumor necrosis factor production in vivo was also observed.     

五种生物材料对大鼠巨噬细胞肿瘤坏死因子α和白细胞介素1 β表达的影响

背景：生物材料的免疫学研究主要包括免疫球蛋白、血清总补体及补体降解产物的血生化定量测定等方面，主要通过细胞学和组织学的检测手段，其评价指标比较单一，无特异性。 目的：以细胞因子（肿瘤坏死因子α和白细胞介素1β）为研究对象，从mRNA水平上对5种生物材料介导的炎症反应进行相关免疫学评价。 设计、时间及地点：对比观察实验，于2004—01／2005—03在上海生物材料研究测试中心完成。 材料：清洁级SD大鼠3只用于原代培养大鼠巨噬细胞。阳性材料：含8％有机锡的聚氟乙烯。阴性材料：聚苯乙烯。实验材料：美国NPG黄合金块、β-磷酸三钙、固化的磷酸钙骨水泥、聚丙交酯乙交酯及聚四氟乙烯。 方法：参照ISO 10993-12标准，用RPMI—1640按1g／5mL比例，37℃72h制备材料的浸提液。将大鼠腹腔巨噬细胞分别给予脂多糖刺激和无脂多糖刺激，脂多糖的终浓度为1．0mg／L，再用不同生物材料的浸提液予以刺激，作用2h后收集细胞，进行反转录-聚合酶链反应检测。 主要观察指标：大鼠巨噬细胞肿瘤坏死因子α和白细胞介素1β的表达强度。 结果：未经脂多糖诱导的大鼠腹腔巨噬细胞与阳性材料及聚四氟乙烯、NPG接触后肿瘤坏死因子α和白细胞介素1β的表达均高于阴性材料，差异均有非常显著性意义（P〈0．05）；聚丙交酯乙交酯中肿瘤坏死因子α的表达与阴性材料相比无明显升高（P〉0．05），白细胞介素1β的表达高于阴性材料，差异有显著性意义（P〈0．05）；β-磷酸三钙和固化的磷酸钙骨水泥中肿瘤坏死因子α和白细胞介素1β的表达与阴性材料比较差异无显著性意义（P〉0．05）。经脂多糖诱导的大鼠腹腔巨噬细胞与阳性材料及聚四氟乙烯、NPG、聚丙交酯乙交酯、β-磷酸三钙及固化的磷酸钙骨水泥接触后肿瘤坏死因子α和白细胞介素1β的表达均高于阴性材料，差异均有非常显著性意义（P〈0．01）。 结论：肿瘤坏死因子α、白细胞介素1β是在分子水平上衡量不同生物材料诱导免疫刺激反应的理想指标。聚四氟乙烯和NPG的生物相容性程度较差，β-磷酸三钙和固化的磷酸钙骨水泥的相容性较好，尤其是固化的磷酸钙骨水泥。     

利多卡因对肿瘤坏死因子α诱导中性粒细胞凋亡的影响

背景:利多卡因被认为有抗炎作用,而其作用机制不清.核转录因子κB是炎症反应的关键环节.目的:观察利多卡因对人体中性粒细胞核转录因子κB激活和中性粒细胞凋亡的影响.设计、时间及地点:对比观察,于2006-10/2007-02在江苏省麻醉学重点实验室完成.材料:肿瘤坏死因子α(O127:B8)购于Sigma公司;外周血标本健康者,受试者知情同意.方法:人体中性粒细胞分为5组:生理盐水对照组、肿瘤坏死因子α组、肿瘤坏死因子α+利多卡因1.0 mmol/L组、肿瘤坏死因子α+利多卡因2.0 mmol/L组、肿瘤坏死因子α+利多卡因4.0 mmol/L组,共同孵育3h.主要观察指标:以反转录聚合酶链反应及免疫印迹法检测利多卡因对核转录因子κBmRNA和I-κB mRNA表达及蛋白含量的影响.孵育12h和24h,以流式细胞术分析对中性粒细胞凋亡的影响.结果:利多卡因组核转录因子κB mRNA表达显著降低,而I-κB mRNA表达显著增加.并凡利多卡因2.0 mmoVL组和4.0 mmol/L组显著优于1.0 mmol/L组(P<0.05),而2.0 mmol/L组和4.0 mmol/L组之间差异不显著(P>0.05).利多卡因在12h和24h都可以显著抑制肿瘤坏死因子α诱导的外周血中性粒细胞凋亡(P<0.05),而4.0 mmol/L组显著优于1.0 mmol/L组(P<0.05).结论:利多卡因1.0,2.0,4.0 mmol/L都可以显著下调肿瘤坏死因子α诱导的外周血中性粒细胞P65mRNA的表达,并且在12和24h可以部分逆转肿瘤坏死因子α诱导的中性粒细胞凋亡.     

Lipopolysaccharide-induced selective priming effects on tumor necrosis factor alpha and nitric oxide production in mouse peritoneal macrophages

Preculture of thioglycollate-elicited C3HeB/FeJ mouse peritoneal macrophages in vitro with subthreshold stimulatory concentrations of lipopolysaccharide (LPS) can induce hyporesponsiveness (desensitization) to both tumor necrosis factor alpha (TNF-alpha) and nitric oxide (NO) production when these cells are subsequently stimulated with 100 ng/ml of LPS. We have established, however, that the primary dose of LPS required for inducing downregulation of NO production is significantly lower than that required for inducing downregulation of TNF-alpha production. Further, when LPS-pretreated macrophages become refractory to subsequent LPS stimulation for NO production, the secondary LPS-stimulated TNF-alpha production is markedly enhanced, and vice versa. These results indicate that LPS- induced TNF-alpha and NO production by macrophages are differentially regulated, and that the observed desensitization process may not reflect a state in which macrophages are totally refractory to subsequent LPS stimulation. Rather, our data suggest that LPS- pretreated macrophages become selectively primed for differential responses to LPS. The LPS-induced selective priming effects are not restricted to LPS stimulation, but extend as well to stimuli such as zymosan, Staphylococcus aureus, and heat-killed Listeria monocytogenes.