Isolation of Acanthamoeba isolates belonging to T2, T3, T4 and T7 genotypes from environmental samples in Ankara, Turkey
Isolation of Acanthamoeba isolates belonging to T2, T3, T4 and T7 genotypes from environmental samples in Ankara, Turkey
复制标题
从土耳其安卡拉的环境样本中分离出属于 T2、T3、T4 和 T7 基因型的棘阿米巴分离株
DOI：
--
复制
发表时间：
2004
期刊：
影响因子：
--
通讯作者：
N. Khan
中科院分区：
文献类型：
--
作者：
A. Kilic;M. Tanyuksel;J. Sissons;S. Jayasekera;N. Khan
棘阿米巴角膜炎是一种致盲感染，对人类健康正变得越来越重要。早期诊断是治疗成功的先决条件，需要在基因水平上对棘阿米巴进行鉴定。棘阿米巴属包括致病和非致病两种，最近被划分为13种不同的基因类型，T1-T12和T14。更重要的是，95%产生角膜炎的棘阿米巴分离株属于T4基因。在这项研究中，我们试图确定棘阿米巴角膜炎中T4分离株的优势是由于更强的毒力还是更高的流行率。我们从土耳其安卡拉的环境样品中分离到18株棘阿米巴，并通过渗透压耐受性、温度耐受性和角膜上皮细胞体外细胞毒性试验测定了它们的致病性。核糖体DNA测序显示，T2型10株，T3型5株，T4型2株，T7型1株。正如预期的那样，T3和T4分离株表现出最多的致病特征，对渗透和温度耐受，并显示出严重的角膜上皮细胞毒性，表明它们具有致病潜力。总体而言，这些数据表明，角膜炎病例中T4分离株的高频率很可能是由于它们的毒力更强。这是首次报道棘阿米巴在土耳其安卡拉的环境分布。
Acanthamoeba keratitis is a blinding infection that is becoming increasingly important in human health. Early diagnosis is a prerequisite for successful treatment and requires identification of Acanthamoeba at the genotypic level. The genus Acanthamoeba consists of both pathogenic and non-pathogenic species and has been recently classified into 13 different genotypes, T1-T12 and T14. More importantly, 95% of Acanthamoeba isolates that produce keratitis belong to T4 genotypes. In this study, we attempted to determine whether predominance of T4 isolates in Acanthamoeba keratitis is due to greater virulence or greater prevalence. We isolated 18 Acanthamoeba isolates from environmental samples in Ankara, Turkey and determined their pathogenic potential by means osmotolerance, temperature tolerance and in vitro cytotoxicity assays using corneal epithelial cells. Ribosomal DNA sequencing revealed that 10 isolates belong to T2, 5 belong to T3, 2 belong to T4 and one belongs to T7 genotype. As expected, T3 and T4 isolates exhibited the most pathogenic traits and were osmotolerant, temperature tolerant and exhibited severe corneal epithelial cell cytotoxicity indicating their pathogenic potential. Overall these data indicate that high frequency of T4 isolates in keratitis cases may well be due to their greater virulence. This is the first report presenting environmental distribution of Acanthamoeba in Ankara, Turkey.