In vivo imaging of trypanosome-brain interactions and development of a rapid screening test for drugs against CNS stage trypanosomiasis.
In vivo imaging of trypanosome-brain interactions and development of a rapid screening test for drugs against CNS stage trypanosomiasis.
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DOI：
10.1371/journal.pntd.0002384
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发表时间：
2013
影响因子：
3.8
通讯作者：
Mottram JC
中科院分区：
文献类型：
--
作者：
Myburgh E;Coles JA;Ritchie R;Kennedy PG;McLatchie AP;Rodgers J;Taylor MC;Barrett MP;Brewer JM;Mottram JC
人类非洲锥虫病（HAT）表现为两个阶段的疾病：首先，血淋巴，其次，脑炎阶段涉及中枢神经系统（CNS）。治疗第二阶段疾病的新药是迫切需要的，但新药候选物的测试是一个缓慢的过程，因为建立的动物模型依赖于检测血液中的寄生虫血症，最迟在治疗后180天。为了加快化合物的筛选，我们已经修改了GVR 35菌株的布氏锥虫布氏，表达荧光素酶，并监测寄生虫分布感染的小鼠治疗后，用杀锥虫的化合物，使用连续的，非侵入性的，生物发光成像。在用diminazene治疗后，在受感染小鼠的大脑中检测到寄生虫，diminazene是一种治疗1期但不能治疗2期疾病的药物。活体多光子显微镜检查显示，锥虫进入脑膜早在感染后第5天，但可以杀死diminazene，而那些穿过血脑屏障，并进入实质的第21天存活治疗，后来引起血流复发。相比之下，所有生物发光寄生虫都被美拉胂醇和DB 829（已知可治愈2期疾病的化合物）永久消除。我们表明，这种成像的使用减少了三分之二的时间来评估药物疗效，并提供了一个双模式成像平台，用于监测锥虫感染的不同区域的大脑。 布氏锥虫是一种通过采采蝇叮咬传播的寄生虫，是引起人类非洲锥虫病（HAT）的原因。在HAT的晚期阶段，锥虫侵入中枢神经系统（CNS），导致一系列神经系统症状，并最终死亡。现有的治疗HAT的药物非常不令人满意，迫切需要新的安全药物。目前，HAT的潜在药物是在小鼠模型中筛选的，该模型依赖于锥虫从组织中的出现及其在血液中的检测。这可能需要长达200天的时间，使得新药的选择和进一步开发缓慢而昂贵。在这里，我们采用体内成像和转基因锥虫监测寄生虫分布在整个身体活感染的小鼠。我们的生物发光成像方法提供了感染部位锥虫的灵敏检测，从而可以更快速，更有效地在体内筛选候选HAT药物。高分辨率活体显微镜被用来调查锥虫在大脑中的动力学和他们的药物在感染过程中的可及性。这些方法允许在慢性感染期间对锥虫进行更灵敏的真实的时间跟踪，并将在未来的实验中提供关于锥虫发病机制的新见解。
Human African trypanosomiasis (HAT) manifests in two stages of disease: firstly, haemolymphatic, and secondly, an encephalitic phase involving the central nervous system (CNS). New drugs to treat the second-stage disease are urgently needed, yet testing of novel drug candidates is a slow process because the established animal model relies on detecting parasitemia in the blood as late as 180 days after treatment. To expedite compound screening, we have modified the GVR35 strain of Trypanosoma brucei brucei to express luciferase, and have monitored parasite distribution in infected mice following treatment with trypanocidal compounds using serial, non-invasive, bioluminescence imaging. Parasites were detected in the brains of infected mice following treatment with diminazene, a drug which cures stage 1 but not stage 2 disease. Intravital multi-photon microscopy revealed that trypanosomes enter the brain meninges as early as day 5 post-infection but can be killed by diminazene, whereas those that cross the blood-brain barrier and enter the parenchyma by day 21 survived treatment and later caused bloodstream recrudescence. In contrast, all bioluminescent parasites were permanently eliminated by treatment with melarsoprol and DB829, compounds known to cure stage 2 disease. We show that this use of imaging reduces by two thirds the time taken to assess drug efficacy and provides a dual-modal imaging platform for monitoring trypanosome infection in different areas of the brain. Trypanosoma brucei, a parasite transmitted by the bite of tsetse fly, is responsible for the disease human African trypanosomiasis (HAT). In advanced stages of HAT, trypanosomes invade the central nervous system (CNS), resulting in an array of neurological symptoms, and eventually death. Existing drugs for treatment of HAT are highly unsatisfactory and new safe drugs are urgently needed. Currently, potential drugs for HAT are screened in a mouse model that relies on the emergence of trypanosomes from tissues and their detection in blood. This can take up to 200 days, making selection and further development of new drugs slow and costly. Here, we employ in vivo imaging and genetically modified trypanosomes to monitor parasite distribution throughout the body in live infected mice. Our bioluminescence imaging approach provides sensitive detection of trypanosomes at sites of infection, allowing more rapid and more effective in vivo screening of candidate HAT drugs. Higher resolution intra-vital microscopy was used to investigate trypanosome dynamics in the brain and their accessibility to drugs during infection. These approaches allow more sensitive real time tracking of trypanosomes during chronic infections and will provide new insights about trypanosome pathogenesis in future experiments.
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影响因子：
3.6
作者：
Contag, CH;Contag, PR;Benaron, DA
通讯作者：
Benaron, DA
影响因子：
16.6
作者：
Conley, Nicholas R.;Dragulescu-Andrasi, Anca;Rao, Jianghong;Moerner, W. E.
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Moerner, W. E.
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McCulloch, Richard
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Murray, M
影响因子：
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作者：
Barretto, Robert P. J.;Messerschmidt, Bernhard;Schnitzer, Mark J.
通讯作者：
Schnitzer, Mark J.