Cell Biological, Epidemiological and Clinical Studies on Entamoeba dispar infection

迪斯帕内阿米巴感染的细胞生物学、流行病学和临床研究

• 批准号: 09470072
• 负责人: TAKEUCHI Tsutomu
• 金额: $ 5.95万
• 依托单位: Keio University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09470072/
• 关键词: アメーバ症; Entamoeba histolytica; Entamoeba disper; 無菌培養; 病原性; 含硫アミノ酸代謝; アメーバ; システイン合成系; 嚢子; peroxiredoxin; Glycogen particle; モノクローナル抗体

As Entamoeba histolytica was reclassified into pathogenic ameba, Entamoeba histolytica, and nonpathogenic one, Entamoeba dispar in 1997, a variety of aspects of these amebae and their infection needed to be reassessed. Accordingly studies on E. dispar infection was attempted. ? Axenic cultivation of E. dispar could be produced with C. fasciculata treated at high temperature and subsequently with hydrogen peroxide, as a culture associate. ? Monoclonal antobodies and their Fab fragments useful for identification of both amebae were produced. ? To clarify the biological properties, metabolism of sulfur-containing aminoacids was investigated. The gene encoding ATP sulfurylase was cloned from E. histolytica and its recombinant protein was characterized. Moreover, the gene encoding cysteine synthase was closed from E. dispar, which demonstrated the presence of two isoforms. Serine acetyltransferase, a regulatory enzyme of cysteine biosynthesis, was also studies by similar approach for both species of amebae, and the properties investigated. These studies clearly demonstrate amebae were the first eukaryote which has a functional cysteine biosynthetic pathway. ? With E. histolytica and E. invadens as a model, a variety of inhibitors were examined for the potential to suppress the growth. Consequently, dinitroaniline herbicides and cytochlasin D were found to inhibit in vitro growth and encystation of the model. ? By epidemiological analysis, only E. histolytica was detected from institutionalized population though all of them were asymptomatic.

由于1997年将溶组织内阿米巴重新分类为致病性阿米巴（Entamoeba histolytica）和非致病性阿米巴（Entamoeba dispar），因此需要重新评估这些阿米巴及其感染的各个方面。因此，对E.尝试感染Dispar。? E.用C. fasciculata处理在高温下，随后与过氧化氢，作为一个文化联想。?制备了用于鉴定两种阿米巴的单克隆抗体及其Fab片段。?为了阐明生物学特性，研究了含硫氨基酸的代谢。从大肠杆菌中克隆了ATP硫酸化酶基因。histolytica及其重组蛋白进行了表征。此外，半胱氨酸合酶基因与E. dispar，其证明了两种同种型的存在。半胱氨酸生物合成的调节酶丝氨酸乙酰转移酶也被用类似的方法研究了两种阿米巴，并对其性质进行了研究。这些研究清楚地表明，阿米巴是第一个具有功能性半胱氨酸生物合成途径的真核生物。?用大肠histolytica和E.作为模型，检测了多种抑制剂抑制生长的潜力。因此，发现二硝基苯胺除草剂和细胞分裂素D抑制该模型的体外生长和包囊化。?流行病学分析表明，仅E.在收容机构的人群中发现溶组织菌，尽管所有人都没有症状。

项目成果

Tachibana H, Cheng X, Takeuchi T et al.: "Preparation of monoclonal antibody Fab fragments specific for Entamoeba histolytica"Clin Diag Lab Immunol. 6. 383-387 (1999)

Tachibana H、Cheng X、Takeuchi T 等人：“溶组织内阿米巴特异性单克隆抗体 Fab 片段的制备”Clin Diag Lab Nutrition。

小林 正規: "Entamoeba dispar: Cultivation with sterilized Crithidia fasciculata" Journal of Eukaryotic Microbiology. 45.2. 3S-8S (1998)

Masanori Kobayashi：“迪斯帕内阿米巴：用灭菌的束状短膜虫进行培养”《真核微生物学杂志》45.2（1998）。

竹内勤: "Entamoeba dispar : Cultivation without viable associate" Archives of Medical Research. 28-suppl. 108-109 (1997)

Tsutomu Takeuchi：“Dispar 内阿米巴：无可行伙伴的培养”医学研究档案 28-suppl。

Nozaki T, Asai T, Takeuchi T: "Codon usage in Entamoeba histolytica, E. dispar and E. invadens"Parasitol Int. 46. 105-109 (1997)

Nozaki T、Asai T、Takeuchi T：“溶组织阿米巴、迪斯帕阿米巴和侵入阿米巴中的密码子使用”Parasitol Int。

Kumagai M, Kobayashi S, Takeuchi T et al.: "Entamoeba invadens: Reversible effect of aphidicolin on the growth and encystation"Exp Parasitol. 90. 294-297 (1998)

Kumagai M、Kobayashi S、Takeuchi T 等人：“内阿米巴入侵：阿菲迪霉素对生长和成囊的可逆作用”Exp Parasitol。