Urquiza Javier, Cevallos Cintia, Elizalde María Mercedes, Delpino M Victoria, Quarleri Jorge
Instituto de Investigaciones Biomédicas en Retrovirus y Sida (INBIRS), Facultad de Medicina, Universidad de Buenos Aires (UBA), Buenos Aires, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina.
Front Microbiol. 2020 Oct 19;11:563320. doi: 10.3389/fmicb.2020.563320. eCollection 2020.
: is an intracellular protozoa and etiological agent that causes Chagas disease. Its presence among the immunocompromised HIV-infected individuals is relevant worldwide because of its impact on the central nervous system (CNS) causing severe meningoencephalitis. The HIV infection of astrocytes - the most abundant cells in the brain, where the parasite can also be hosted - being able to modify reactive oxygen species (ROS) could influence the parasite growth. In such interaction, extracellular vesicles (EVs) shed from trypomastigotes may alter the surrounding environment including its pro-oxidant status. : We evaluated the interplay between both pathogens in human astrocytes and its consequences on the host cell pro-oxidant condition self-propitiated by the parasite - using its EVs - or by HIV infection. For this goal, we challenged cultured human primary astrocytes with both pathogens and the efficiency of infection and multiplication were measured by microscopy and flow cytometry and parasite DNA quantification. Mitochondrial and cellular ROS levels were measured by flow cytometry in the presence or not of scavengers with a concomitant evaluation of the cellular apoptosis level. : We observed that increased mitochondrial and cellular ROS production boosted significantly infection and multiplication in astrocytes. Such oxidative condition was promoted by free trypomastigotes-derived EVs as well as by HIV infection. : The pathogenesis of the HIV- coinfection in astrocytes leads to an oxidative misbalance as a key mechanism, which exacerbates ROS generation and promotes positive feedback to parasite growth in the CNS.
:是一种细胞内原生动物和致病因子,可引起恰加斯病。由于其对中枢神经系统(CNS)造成严重脑膜脑炎,在全球范围内,免疫功能低下的HIV感染个体中其存在具有重要意义。星形胶质细胞是大脑中数量最多的细胞,寄生虫也可在其中寄生,HIV对星形胶质细胞的感染能够改变活性氧(ROS),这可能会影响寄生虫的生长。在这种相互作用中,从锥鞭毛体脱落的细胞外囊泡(EVs)可能会改变周围环境,包括其促氧化状态。:我们评估了两种病原体在人星形胶质细胞中的相互作用,以及其对宿主细胞由寄生虫(利用其EVs)或HIV感染引发的促氧化状态的影响。为了实现这一目标,我们用这两种病原体对培养的人原代星形胶质细胞进行攻击,并通过显微镜、流式细胞术和寄生虫DNA定量来测量感染和增殖效率。在有或没有清除剂的情况下,通过流式细胞术测量线粒体和细胞ROS水平,同时评估细胞凋亡水平。:我们观察到,线粒体和细胞ROS产生的增加显著促进了星形胶质细胞中的感染和增殖。这种氧化状态是由游离锥鞭毛体衍生的EVs以及HIV感染所促进的。:星形胶质细胞中HIV合并感染的发病机制导致氧化失衡,这是一个关键机制,它会加剧ROS的产生,并促进对中枢神经系统中寄生虫生长的正反馈。