Spencer Angela M, Goethert Heidi K, Telford Samuel R, Holman Patricia J
Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas 77843, USA.
J Parasitol. 2006 Apr;92(2):333-40. doi: 10.1645/GE-662R.1.
A Babesia sp. isolated from eastern cottontail rabbits (Sylvilagus floridanus) is morphologically similar and genetically identical, based on SSU rRNA gene comparisons, to 2 agents responsible for human babesiosis in the United States. This zoonotic agent is closely related to the European parasite, Babesia divergens. The 2 organisms were characterized by in vitro comparisons. In vitro growth of the rabbit Babesia sp. was supported in human and cottontail rabbit erythrocytes, but not in bovine cells. Babesia divergens was supported in vitro in bovine and human erythrocytes, but not in cottontail rabbit cells. Morphometric analysis classifies B. divergens as a small babesia in bovine erythrocytes, but the parasite exceeds this size in human erythrocytes. The rabbit Babesia sp. is large, the same size in both human or rabbit erythrocytes, and is significantly larger than B. divergens. Eight or more rabbit Babesia sp. parasites may occur within a single erythrocyte, sometimes in a floret array, unlike B. divergens. The erythrocyte specificity and morphological differences reported in this study agree with previous in vivo results and validate the use of in vitro methods for characterization of Babesia species.
从东部棉尾兔（佛罗里达棉尾兔）分离出的一种巴贝斯虫（Babesia sp.），基于小亚基核糖体RNA（SSU rRNA）基因比较，在形态学上相似且基因相同，与美国两种引起人类巴贝斯虫病的病原体相同。这种人畜共患病原体与欧洲寄生虫分歧巴贝斯虫（Babesia divergens）密切相关。通过体外比较对这两种生物体进行了表征。兔巴贝斯虫（Babesia sp.）在人及棉尾兔红细胞中能在体外生长，但在牛细胞中不能。分歧巴贝斯虫在牛和人红细胞中能在体外生长，但在棉尾兔细胞中不能。形态测量分析将分歧巴贝斯虫在牛红细胞中归类为小巴贝斯虫，但该寄生虫在人红细胞中超过此大小。兔巴贝斯虫较大，在人或兔红细胞中大小相同，且明显大于分歧巴贝斯虫。单个红细胞内可能出现八个或更多的兔巴贝斯虫寄生虫，有时呈小花状排列，这与分歧巴贝斯虫不同。本研究中报道的红细胞特异性和形态学差异与先前的体内结果一致，并验证了体外方法用于巴贝斯虫物种表征的有效性。
