El-Sayed Nagwa Mostafa, Ismail Khadiga Ahmed, Badawy Abeer Fathy, Elhasanein Khaled Fathy
Medical Parasitology Department, Research Institute of Ophthalmology, Ministry of Scientific Research and Technology, Giza, Egypt.
Parasitology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt.
J Parasit Dis. 2016 Dec;40(4):1459-1465. doi: 10.1007/s12639-015-0712-y. Epub 2015 Sep 24.
(), an intracellular parasite, establishes a chronic infection by forming cysts preferentially in the brain. TNF-α plays an important role in controlling the infection caused by this protozoan. Thus, the blockade of TNF-α could cause reactivation of latent toxoplasmosis infection as well as increase the risk of acute toxoplasmosis. This study evaluated the effect of etanercept, a TNF-α antagonist in reactivation of latent toxoplasmosis compared to the therapeutic effect of sulfadiazine and pyrimethamine in combination on the progress of the disease. A total of 40 laboratory-bred Swiss albino mice were infected with Me49 strain of and divided into four groups: infected control group; treated group with sulfadiazine and pyrimethamine; treated group with etanercept and treated group with both etanercept and sulfadiazine and pyrimethamine. The mean number and size of tissue cysts in brain smears of mice of each group were determined and also, serum levels of TNF-α were assessed in different study groups by an enzyme linked immunosorbent assay. The results showed that the mean TNF-α level was significantly different in the treated groups compared to that in infected control group. The highest level of TNF-α was found in the infected controls. After treatment with etanercept alone or combined with sulfadiazine and pyrimethamine, it was significantly decreased. In this study, reactivation of latent toxoplasmosis was observed by a significant increase in the mean number and sizes of tissue cysts in brains of mice with established chronic toxoplasmosis after treatment with etanercept alone or combined with conventional treatment compared to both untreated chronically infected controls and infected mice treated with sulfadiazine and pyrimethamine. It was concluded that etanercept, a TNF-α antagonist may play a role in reactivation of latent toxoplasmosis. So, serological screening for toxoplasmosis might offer a valuable aid for patients treated with this drug.
（）是一种细胞内寄生虫，通过优先在大脑中形成囊肿来建立慢性感染。肿瘤坏死因子-α（TNF-α）在控制这种原生动物引起的感染中起重要作用。因此，阻断TNF-α可能导致潜伏性弓形虫病感染的重新激活，并增加急性弓形虫病的风险。本研究评估了TNF-α拮抗剂依那西普对潜伏性弓形虫病重新激活的影响，并将其与磺胺嘧啶和乙胺嘧啶联合治疗对疾病进展的疗效进行了比较。总共40只实验室饲养的瑞士白化小鼠感染了（此处原文缺失具体感染物名称）的Me49株，并分为四组：感染对照组；磺胺嘧啶和乙胺嘧啶治疗组；依那西普治疗组；依那西普与磺胺嘧啶和乙胺嘧啶联合治疗组。测定了每组小鼠脑涂片组织囊肿的平均数量和大小，并且通过酶联免疫吸附测定法评估了不同研究组中的TNF-α血清水平。结果表明，与感染对照组相比，治疗组的平均TNF-α水平有显著差异。感染对照组中TNF-α水平最高。单独使用依那西普或与磺胺嘧啶和乙胺嘧啶联合治疗后，其水平显著降低。在本研究中，与未治疗的慢性感染对照组和用磺胺嘧啶和乙胺嘧啶治疗的感染小鼠相比，单独使用依那西普或与传统治疗联合治疗后，已建立慢性弓形虫病的小鼠大脑中组织囊肿的平均数量和大小显著增加，观察到潜伏性弓形虫病的重新激活。得出的结论是，TNF-α拮抗剂依那西普可能在潜伏性弓形虫病的重新激活中起作用。因此，对弓形虫病进行血清学筛查可能为使用该药物治疗的患者提供有价值的帮助。
