致弱RH株弓形虫抗小鼠B16黑色素瘤的实验研究

目的观察紫外线辐照致弱RH株弓形虫对小鼠体内黑色素瘤生长的抑制作用。方法1×10^7紫外线致弱RH株弓形虫速殖子经腹腔注射免疫C57BL/6J小鼠,7d后再次接种相同数量弓形虫,并在接种当天给小鼠荷瘤,在荷瘤后21d处死小鼠,测定小鼠肿瘤体积与质量,并检测脾细胞T细胞亚群和淋巴细胞杀伤活性。结果致弱弓形虫能够显著抑制肿瘤生长,实验组小鼠肿瘤体积与质量显著小于对照组（P〈0．05）,抑瘤率为52．09％。实验组小鼠脾细胞CD3^＋、CD4^＋、CD8^＋、CD4^＋／CD8^＋、NK细胞杀伤活性显著高于对照组（P〈0．05）。结论致弱免疫弓形虫可以抑制小鼠体内黑色素瘤生长。     

双抗体夹心免疫-PCR检测弓形虫循环抗原的实验研究

目的探索弓形虫病的病原学检测方法。方法用游离的亲合素将生物素化的二抗和生物素化的腺病毒六邻体基因重组质粒DNA偶联起来,通过PCR扩增标记的DNA检测弓形虫循环抗原,建立了免疫-PCR检测方法;用该方法和ELISA法平行检测感染鼠的血清,对比研究两者敏感性及循环抗原的检出时间。结果免疫-PCR法检测弓形虫循环抗原阳性血清的最大稀释度为1∶2560,ELISA法为1∶10;免疫-PCR法在感染后第2天检测到循环抗原,ELISA法在第4天检测到循环抗原。结论免疫-PCR是一种特异性高、敏感性强的弓形虫循环抗原的检测方法,可作为弓形虫病病原学的诊断方法。     

弓形虫速殖子质抗原、膜抗原及分泌代谢抗原对免疫小鼠的保护性研究

弓形虫病是一种世界分布的人兽共患寄生虫病,人类对弓形虫普遍易感。随着社会经济的发展,养宠物者增多,使人们感染弓形虫的机率增加。成人感染弓形虫后多无临床症状,但在AIDS、恶性肿瘤等免疫低下和免疫抑制患者中, 弓形虫作为一种机会性感染因子,是引发致死的病因之     

肿瘤细胞裂解物抗小鼠B16F10黑色素瘤的作用研究

反复冻融B16F10肿瘤细胞制备裂解物,以白喉毒素(Diphtheria toxin,DT)为载体,OK432和来源于结核分枝杆菌(Mycobacterium tuberculosis)热休克蛋白70(HSP70)第407-426(mHSP70407～426,M)的两段串联重复序列M2为佐剂,制备了肿瘤细胞疫苗B16F10-DT-M2-OK432(BDTMOK),探讨其能否抑制小鼠B16黑色素瘤,并且对其抗肿瘤的作用机理进行部分探讨。以制备的BDTMOK免疫C57BL/6小鼠,分别检测体液免疫应答和细胞免疫应答。通过ELISA法,从血清中检测到高滴度的抗B16肿瘤细胞裂解物(B16 tumor cell lysate,B16TCL)类抗体。淋巴细胞增殖实验的结果显示,BDTMOK的免疫能够有效的刺激脾淋巴细胞的增殖。预防结合治疗性实验的结果显示,BDTMOK激发的免疫应答对于B16肿瘤攻击起到有效的保护作用,与PBS阴性对照组比较,皮下注射BDTMOK可以延长皮下移植瘤发生的潜伏期(P<0.05),并且平均瘤重显著降低(P<0.05);抑制了小鼠皮内肿瘤模型中的血管新生(P<0.01)。疫苗BDTMOK能有效的抑制小鼠B16黑色素瘤的生长。     

弓形虫病实验诊断与优生

应用酶联免疫吸附实验(ELISA)法,检测492名孕妇血中弓形虫抗体、阳性率为4.4％,其中异常分娩组的抗体阳性率为14.1％,正常分娩组的阳性率为1.5％,有显著差异,有反复流产史的阳性率为43％,实验证明,弓形虫感染是不良妊娠的重要原因。     

一种植物提取物抑制小鼠B16黑色素瘤生长的作用

目的观察一种植物提取物对小鼠B16黑色素瘤生长的影响。方法采用C57品系雌性小鼠皮下接种B16黑色素瘤细胞建立模型,24h后分别给予不同剂量的植物提取物、阴性对照生理盐水、阳性对照顺铂,连续治疗15d。于接种开始第1、8、12和16天检测各组小鼠的体重、肿瘤面积、肿瘤重量、脾脏重量。结果用药16d后,阳性对照组、植物提取物组肿瘤面积和质量较生理盐水组显著降低(P<0.05),第4组植物提取物抑瘤率为45%,对黑色素瘤的生长有明显的抑制作用。植物提取物组小鼠体质量与生理盐水组比较无统计学意义。结论此植物提取物对黑色素瘤有抑制作用。     

弓形虫病的免疫学诊断进展

弓形虫病是全球广泛分布、对人类造成严重危害的人兽共患病。多见于艾滋病患者和肿瘤病人，而先天性弓形体病可导致流产、早产、畸胎、死胎等。因此，弓形虫病的防治和早期诊断已引起人们关注，必须寻找一种敏感而特异的早期诊断方法和诊断试剂。同国外的一些试剂盒相比，目前我国还缺少令人满意的诊断试剂盒。本文简要介绍近年弓形虫病免疫学检测有关的抗原及抗体研究。     

Inhibitory effect of antidepressants on B16F10 melanoma tumor growth

BackgroundAntidepressant drugs, like fluoxetine, a selective serotonin reuptake inhibitor, desipramine, a nonselective noradrenaline reuptake inhibitor, and mirtazapine, an antagonist of noradrenaline α₂ auto- and heteroreceptors, are widely used for the treatment of depressive symptoms in cancer patients. Since these antidepressants have different activities targeting the immune system, they might also modulate tumor growth in cancer patients.MethodsIn the present study, we investigated the effects of administration of antidepressant drugs: fluoxetine, desipramine and mirtazapine on B16F10 melanoma tumor growth. These drugs were administered intraperitoneally (ip) for 17 days after subcutaneous injection of B16F10 melanoma cells to male C57BL/6J mice.ResultsFluoxetine significantly inhibited melanoma solid tumor growth and desipramine tended to decrease this parameter whereas mirtazapine had no effect.ConclusionThe inhibitory effect of fluoxetine on melanoma growth was associated with an increased mitogen-induced T cell proliferation which may at least partly participate in the mechanism of the antitumor effect of this antidepressant. It appears that the inhibitory effect of fluoxetine on tumor growth is not related with changes in cytokine levels except for IL-10.     

南瓜蛋白对B16细胞的诱导分化作用

目的测定南瓜蛋白对小鼠黑色素瘤B16细胞的诱导分化作用。方法以MTT法测定南瓜蛋白对B16细胞的增殖抑制作用,并以形态学、黑色素含量及细胞周期变化为指标,观察南瓜蛋白诱导B16细胞分化的作用。结果南瓜蛋白对B16细胞具有明显的增殖抑制作用,并阻止B16细胞由G1期向S期过渡从而停滞于G1期;细胞形态向正常上皮样细胞分化,生长缓慢,平铺不重叠,甚至形成网状结构,胞质内细胞器丰富,黑色素小体明显增多;黑色素含量增加。结论南瓜蛋白对B16细胞具有明显的诱导分化作用。     

特异性抗原致敏的DC-CIK细胞对B16黑色素瘤多途径抑瘤作用的研究

目的探讨特异性抗原致敏的树突状细胞(dentritic cells,DC)与细胞因子诱导的杀伤细胞(cytokine induced killer,CIK)细胞对B16黑色素瘤的作用。方法采用特异性肿瘤抗原致敏的DC与CIK细胞共同培养,分析其免疫表型,计算抑瘤率;流式细胞(FCM)检测癌细胞增殖周期中G0/G1期、S期、G2/M期细胞比率和细胞凋亡指数(apoptosis Index,AI)、细胞增殖指数(proliferation Index,PI)的变化;透射电镜观察形态学变化;并用MTT法检测其对肿瘤细胞的杀伤力。结果特异性抗原致敏的DC-CIK细胞组抑瘤率高于DC-CIK组和CIK组;FCM检测G0/G1期细胞比率、AI显著升高,S期无明显变化,G2/M期细胞比率、PI显著下降;特异性抗原致敏的DC-CIK细胞组杀伤活性明显升高(P<0.05)。结论特异性抗原致敏的DC-CIK细胞对B16黑色素瘤的抑瘤作用明显高于DC-CIK细胞和单纯CIK细胞。     

Altered tumor angiogenesis and metastasis of B16 melanoma in transgenic mice overexpressing tissue inhibitor of metalloproteinases-1

Tissue inhibitor of metalloproteinases-1 (TIMP-1) has emerged as a multifunctional protein that plays contrasting roles during angiogenesis and cancer spread. We have investigated the growth, vascularization and metastasis of B16 melanoma cells in a transgenic mouse model with elevated TIMP-1 levels in the systemic circulation. Transgenic C57BL/6j-CBA mice overexpressing human TIMP-1 in the liver under the control of the mouse albumin promoter/enhancer were employed. An early subcutaneous growth advantage and an increased tumor angiogenic response were observed in transgenic animals with respect to wild-type hybrid mice. On the contrary, there was a dramatic decrease in the lung colonizing ability of B16 melanoma cells in TIMP-1 transgenic mice. No significant effect on metastasis formation was observed in another transgenic mouse model with increased TIMP-1 expression in lungs but low plasma levels, where the transgene was placed under the control of the murine mammary tumor virus promoter. These results support the notion that TIMP-1 displays paradoxical effects on tumor progression and suggest that circulating TIMP-1 is efficient in suppressing lung colonization of melanoma cells.     

Age-dependent stimulatory effect of desipramine and fluoxetine pretreatment on metastasis formation by B16F10 melanoma in male C57BL/6 mice

Although recent data may provide theoretical support for the preventive use of antidepressants in cancer patients, so far no study has demonstrated the clinical benefits of such strategies in the general population of cancer patients [39, 41]. Moreover, an association between antidepressant use and the risk of tumor promotion could neither be excluded nor established.The aim of this study was to compare the effect of desipramine (a tricyclic antidepressant, TCA) and fluoxetine (a selective serotonin reuptake inhibitor, SSRI) on tumor growth of the mouse B16F10 transplanted melanoma in “young” 6–9 month old and “aged” 18–23 month old male C57BL/6 mice. Drugs were administered daily at a dose of 10 mg/kg, ip, for two weeks and tumor cells were inoculated 2 h after the last antidepressant administration. Control animals were treated with saline. Tumor growth was significantly slower in aged than in young saline-treated control animals. Pretreatment with desipramine dramatically promoted metastasis formation and increased mortality rate but inhibited primary tumor growth in young males. On the other hand, both antidepressants increased primary tumor growth in aged animals, whereas metastasis was only moderately promoted. To determine the effect of antidepressant drug pretreatment and tumor progress on some parameters of cell-mediated immunity (proliferative activity and cytokine production by splenocytes) and angiogenesis, vascular endothelial growth factor (VEGF) and metalloproteinase (MMP)-9 plasma levels were established. The prometastatic effect of desipramine in young animals was connected with an increase of VEGF and MMP-9 plasma levels.     

3种中药注射剂对小鼠移植性S180肉瘤血管形成抑制作用

目的：探讨苦参素、莪术油以及薏苡仁3种药物注射剂对肿瘤血管形成抑制作用。方法：通过建立动物肿瘤模型，运用3种药物分别实验治疗，结合免疫组化，检测其抑瘤率和肿瘤内血管密度，以及瘤体血管内皮生长因子(VEGF)和碱性成纤维细胞生长因子(bFGF)表达的改变。结果：苦参素、莪术油、薏苡仁3种药物具有明显的抑制肿瘤生长作用，其大剂量组抑瘤率分别为31．36％，46．68％．46．21％。3个药物大剂量实验组的S180瘤体内微血管密度均明显低于对照组；免疫组化显示苦参素、莪术油、薏苡仁大剂量组均可抑制S180瘤体内vEGF、bFGF的表达。结论：苦参素、莪术油、薏苡仁均对小鼠S180肉瘤有一定的抑制作用，对肿瘤血管形成均有明显抑制作用，降低VEGF、bFGF的表达可能是其抑制肿瘤血管形成的主要机制之一.     

辛伐他汀对荷瘤小鼠抑瘤作用的实验研究

目的研究辛伐他汀对小鼠肝癌细胞H22抑瘤作用的影响.方法采用小鼠H22肝癌细胞实体瘤模型进行体内抑瘤实验,观察荷瘤动物的生长情况和肿瘤生长曲线,测定肿瘤生长抑制率,以及生存期的改变.结果辛伐他汀对小鼠的H22实体瘤生长具有明显的抑制作用,抑瘤率达50%以上.未发现生存期的改变.结论辛伐他汀具有较强的体内抗肿瘤作用.     

Effects of benzoylphenyl ureas on growth of B16 melanoma cells in vitro and in vivo

Summary New analogs of diflubenzuron, a benzoylphenyl urea, are tested on their in vitro cytostatic activity against B16 melanoma cells. The following structure-activity relationship was established: substitution by a hydroxylated function at the ortho, meta or para position or by a dimethylamino function at the ortho position of the benzoyl moiety appeared to be necessary for cytostatic activity in vitro. Acetoxy functions at the ortho position or hydroxy functions at the para position of the aniline ring resulted also in active compounds. A number of these benzoylphenyl ureas are selected for in vivo evaluation of antitumor activity on B16 melanoma growing s.c. Although many of the tested benzoylphenyl ureas delayed tumor growth during the first ten days of drug treatment, only a few increased animal life span. The best results (%T/C) were obtained with compounds 5 (127%), 7 (147%), 13 (135%) and 16 (135%), which all have hydroxylated functions in the benzoyl moiety.     

Induction of apoptosis by sulforaphane in highly metastatic B16F-10 melanoma cells

Sulforaphane (SFN) is a naturally occurring isothiocyanate found in cruciferous vegetables, such as broccoli, cabbage, cauliflower, etc. SFN has received a great deal of attention because of its ability to inhibit cell proliferation and induce apoptosis in several tumor cell lines. Previously, we have demonstrated that SFN inhibits the metastasis of B16F-10 melanoma cells in both in vivo and in vitro models. Melanomas are among the aggressive tumor types because of their notorious resistance to treatment and their high tendency to metastasize. In this study, we investigated the influence of SFN on the induction of apoptosis in B16F-10 melanoma cells, which was evidenced by morphological changes such as membrane blebbing, presence of apoptotic bodies, DNA condensation, and also by nuclear DNA fragmentation. SFN-induced apoptosis was associated with the activation of caspases 3 and 9, Bax, and p53 and the downregulation of Bcl-2, caspase-8, Bid, and NF-kB. Caspase-3 is a most likely candidate to mediate SFN-induced apoptosis. In addition to the caspase-dependent pathway, our results also showed the involvement of proinflammatory cytokines, namely tumor necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-6, IL-12p40, and granulocyte-macrophage colony-stimulating factor (GM-CSF), and the nuclear translocation of factors kappa B (NF-κB) p65, NF-κB p50, NF-κB c-Rel, c-FOS, ATF-2, and CREB-1 in SFN-induced apoptosis. These results raise the possibility that SFN may be a promising candidate for molecular-targeting chemotherapy against melanoma.