Kegler K, Habierski A, Hahn K, Amarilla S P, Seehusen F, Baumgärtner W
Department of Pathology, University of Veterinary Medicine, Bünteweg 2, D-30559 Hannover, Germany.
J Comp Pathol. 2013 Aug-Oct;149(2-3):156-61. doi: 10.1016/j.jcpa.2012.11.241. Epub 2013 Jan 21.
A 2-year-old female boxer dog was presented with a vaginal serosanguineous discharge not associated with oestrus. There was a friable mass occupying the upper caudal part of the vagina. Cytological and histological examination revealed a monomorphic population of neoplastic round cells consistent with canine transmissible venereal tumour (TVT). In addition, Leishmania spp. amastigotes were found within the neoplastic tissue. In order to characterize whether the amastigotes were present inside macrophages and/or neoplastic cells, a co-localization study using cell- and pathogen-specific markers was performed. To detect Leishmania spp. a 5.8S ribosomal RNA (rRNA) parasite-specific sequence was used for in-situ hybridization and Mac387 was used as a macrophage marker for immunohistochemistry. Leishmania spp. rRNA was detected inside Mac387(+) macrophages and within the cytoplasm of some neoplastic cells. DNA isolation and polymerase chain reaction using specific primers and sequencing analysis identified the organism as Leishmania infantum (syn. Leishmania chagasi). This is the first report describing infection of tumour cells by L. infantum in a genital TVT from an asymptomatic bitch. Transplantation of Leishmania-laden neoplastic cells could represent an alternative route of venereal transmission of leishmaniasis among dogs.
一只2岁雌性拳师犬出现阴道血性浆液性分泌物，与发情无关。阴道尾端上部有一个易碎肿物。细胞学和组织学检查显示，有一群形态单一的肿瘤性圆形细胞，符合犬传染性性病肿瘤（TVT）。此外，在肿瘤组织内发现了利什曼原虫属无鞭毛体。为了确定无鞭毛体是否存在于巨噬细胞和/或肿瘤细胞内，利用细胞和病原体特异性标记物进行了共定位研究。为检测利什曼原虫属，使用5.8S核糖体RNA（rRNA）寄生虫特异性序列进行原位杂交，并使用Mac387作为巨噬细胞标记物进行免疫组织化学。在Mac387（+）巨噬细胞内和一些肿瘤细胞的细胞质中检测到利什曼原虫属rRNA。通过DNA分离、使用特异性引物的聚合酶链反应和测序分析，确定该生物体为婴儿利什曼原虫（同义名：恰加斯利什曼原虫）。这是第一份描述无症状母犬生殖器TVT中肿瘤细胞被婴儿利什曼原虫感染的报告。携带利什曼原虫的肿瘤细胞移植可能是犬利什曼病在犬之间性传播的另一种途径。
