Trypanosome apoptotic factor mediates apoptosis in human brain vascular endothelial cells
Trypanosome apoptotic factor mediates apoptosis in human brain vascular endothelial cells
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DOI：
10.1016/j.molbiopara.2003.10.011
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发表时间：
2004-02-01
影响因子：
1.5
通讯作者：
Bond, VC
中科院分区：
文献类型：
--
作者：
Stiles, JK;Whittaker, J;Bond, VC
人类非洲锥虫病(HAT，昏睡病)是一种由感染布氏锥虫引起的破坏性疾病。这些血鞭毛侵入中枢神经系统(CNS)，导致脑膜脑炎、神经元脱髓鞘、血脑屏障(BBB)功能障碍、血管周围浸润、星形胶质细胞增多和细胞凋亡。这些表现的分子基础尚不清楚。我们先前报道了布鲁氏杆菌在寄生虫血症高峰期诱导小鼠小脑和脑干核团的细胞凋亡。在这里，我们鉴定并鉴定了一种由布氏锥虫表达的锥虫凋亡因子(TAF)，它介导了小鼠脑和人脑血管内皮细胞(HBVEC)的凋亡。分子、生化和细胞凋亡分析，结合表面增强激光解吸电离(SELDI)和蛋白质数据库分析表明，TAF是一种可溶性的、无血清的、寄生虫来源的、热不稳定的蛋白质，可引起HBVEC的DNA梯状条带和细胞凋亡。蛋白芯片分析感染小鼠血清和原循环培养上清液的SELDI谱显示在8652.7 Da处有一个单一的主峰。进一步的数据库分析表明，TAF可能是原环素或原环素衍生物。合成的27肽(ProEP2-1)对应于EP原环素(EP2-1)的共同区域，可诱导HBVEC和小鼠小脑的凋亡，其诱导作用与布氏支原体感染小鼠相似。利用抗原环素单抗(MAb)进行的Western印迹分析表明，TAF存在于感染的脑组织裂解物中，但不存在于未感染的脑组织裂解物中。此外，该单抗在体外可阻断T brucei和ProEP2-1诱导的HBVEC的凋亡。我们认为布鲁氏杆菌TAF或其衍生物(S)在HAT病理相关的细胞凋亡中起主要作用。(C)2003爱思唯尔B.V.保留所有权利。
Human African trypanosomiasis (HAT, sleeping sickness) is a devastating disease caused by infection with Trypanosoma brucei ssp. These hemoflagellates invade the central nervous system(CNS) and induce meningo-encephalitis, neuronal demyelination, blood-brain-barrier (BBB) dysfunction, peri-vascular infiltration, astrocytosis and apoptosis. The molecular basis of these manifestations is unclear. We previously reported T brucei-induced apoptosis in cerebella and brain-stem nuclei in mice at peak parasitemia. Here, we identify and characterize a trypanosome apoptotic factor (TAF) expressed by T brucei that mediates apoptosis in mouse-brain and human-brain vascular endothelial cells (HBVEC). Molecular, biochemical and apoptotic assays, coupled with surface enhanced laser desorption ionization (SELDI), and protein database analyses were utilized to show that TAF is a soluble, non-serum, parasite-derived, heat-labile protein that causes DNA laddering and apoptosis in HBVEC. Protein-chip assay analysis of the SELDI spectrum of infected mouse serum and procyclic culture supernatants revealed a single major peak at 8652.7 Da. Further database analysis indicated that the TAF may be a procyclin or procyclin derivative. A synthetic 27 mer peptide (ProEP2-1), corresponding to a region common to EP procyclins (EP2-1), induced apoptosis in HBVEC and in cerebella of mice similar to that induced in T brucei-infected mice. Western blot analysis utilizing an anti-procyclin monoclonal antibody (mAb) revealed that TAF is present in infected but not uninfected brain tissue lysates. Furthermore, this mAb blocked T brucei- and ProEP2-1-induced apoptosis in HBVEC in vitro. We conclude that T brucei TAF or its derivative(s) play a major role in the apoptosis associated with HAT pathology. (C) 2003 Elsevier B.V. All rights reserved.