Comparison of US and European Babesia divergens Isolates

美国和欧洲分歧巴贝斯虫分离株的比较

• 批准号: 6601422
• 负责人: PATRICIA J HOLMAN
• 金额: $ 7.28万
• 依托单位: TEXAS A&M UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-04-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6601422
• 关键词: Babesia; animal tissue; babesiosis; computer assisted sequence analysis; erythrocytes; genetic strain; geographic site; heat shock proteins; host organism interaction; microorganism classification; microorganism culture; nucleic acid purification; nucleic acid sequence; parasite infection mechanism; plasmids; polymerase chain reaction; protein structure function; ribosomal RNA; serum; species difference; transfection /expression vector

DESCRIPTION (provided by the applicant): Babesia divergens is a tick transmitted hemoprotozoan parasite that causes human Babesiosis in Europe. Neither B. divergens nor its vector tick are indigenous to the U.S. However, a recent case of acute Babesiosis in a resident of Kentucky was shown to be caused by a parasite morphologically indistinguishable from European Babesia divergens. The parasite in the Kentucky case was found to differ in the small subunit ribosomal RNA gene sequence at only 3 base positions from that of European B. divergens, providing evidence of conspecifity. Recently a Babesia isolate from cottontail rabbits on Nantucket Island was reported to have an identical gene sequence to that of the Kentucky parasite. Molecular epidemiology has also identified this parasite in Ixodes ticks on Nantucket Island, suggesting that an enzootic situation exists. The identification of another Babesia sp. in the US capable of causing human babesiosis is of major concern. Two other Babesia species that cause human Babesiosis in the US, Babesia microti, occurring mostly in the northeastern U.S., and the WA1 isolate, occurring in Washington state and California, have been implicated in blood transfusion acquired cases of babesiosis. Thus, the finding that another previously unknown human blood pathogen is troublesome. The purpose of this study is to compare the culture requirements and target genes of the Kentucky and Nantucket Babesia isolates with European B. divergens (Purnell strain) to determine if conspecificity exists among these parasites. Specific aims include establishing in vitro cultures of the Nantucket isolate and molecular comparison of ITS, HSP70, and cysteine protease genes from European B. divergens with those of the Kentucky and Nantucket isolates. Cultures of the Nantucket isolate will provide an unlimited source of parasites to complete these goals and for future studies. The molecular aspects may provide information that will be useful in future efforts to devise diagnostic tests.

描述（由申请方提供）：分歧巴贝斯虫是一种蜱传播的血原虫寄生虫，在欧洲引起人类巴贝斯虫病。也不是B。然而，最近肯塔基州居民的急性巴贝斯虫病病例显示是由一种形态上与欧洲巴贝斯虫无法区分的寄生虫引起的。发现肯塔基州病例中的寄生虫与欧洲B的寄生虫在小亚基核糖体RNA基因序列中仅3个碱基位置不同。divergens，提供同种性的证据。最近，据报道，从南图克特岛的棉尾兔中分离出的巴贝虫与肯塔基州寄生虫具有相同的基因序列。分子流行病学也在南图克特岛的硬蜱中发现了这种寄生虫，这表明存在地方性流行情况。 在美国鉴定出另一种能够引起人类巴贝虫病的巴贝虫属是一个重大问题。在美国引起人类巴贝斯虫病的另外两种巴贝斯虫，主要发生在美国东北部的小巴贝斯虫，而在华盛顿州和加州出现的WA 1分离株与输血获得性巴贝虫病病例有关。因此，发现另一种以前未知的人类血液病原体是很麻烦的。 本研究的目的是比较肯塔基州和南图克特巴氏杆菌分离株与欧洲B的培养要求和靶基因。divergens（Purnell株），以确定这些寄生虫之间是否存在同种性。具体目标包括建立南图克特分离株的体外培养物和欧洲B的ITS、HSP 70和半胱氨酸蛋白酶基因的分子比较。与肯塔基州和南图克特分离物的分离物不同。南图克特分离株的培养将为完成这些目标和未来的研究提供无限的寄生虫来源。分子方面可能提供的信息，将是有用的，在未来的努力，设计诊断测试。