Helman Elisa, Dellarupe Andrea, Cifuentes Sabrina, Chang Reissig Elizabeth, Moré Gastón
Argentinean National Council of Scientific and Technological Research (CONICET), Godoy Cruz 2290 (C1425FQB) CABA, Buenos Aires, Argentina.
Laboratory of Immunoparasitology (LAINPA), Faculty of Veterinary Sciences, National University of La Plata (FCV-UNLP), Calle 60 Y 118, 1900, La Plata, Buenos Aires, Argentina.
Parasitol Res. 2023 Feb;122(2):471-478. doi: 10.1007/s00436-022-07743-w. Epub 2022 Dec 6.
Sarcocystis spp. are intracellular protozoan parasites with an obligatory heteroxenous life cycle. The objective of this study is to identify Sarcocystis spp. in wild boar muscles from Argentina by light and transmission electron microscopy and molecular characterization. Muscle samples from diaphragm, tongue, masseter, intercostals, heart, and forelimbs of 240 wild boars were analyzed. Of the animals, 48.3% (116/240) were positive for sarcocysts by light microscopy, whereas 45.8% (110/240) were positive for Sarcocystis spp. by PCR targeting 18S rRNA fragment. These samples were subjected to a specific PCR for S. suihominis coxI gene, 3.6% (4/110) of which were weak positives. Unfortunately, sequence analysis was inconclusive. This could be related to a potentially low S. suihominis cyst load in the samples, or to an incomplete primer matching with the South American S. suihominis sequences. Seventeen individual sarcocysts were positive by PCR for the 18S rRNA fragment, whose sequences showed 99.75-100% identity with each other and with previously reported S. miescheriana sequences. A total of 21 cysts collected from 11 muscle samples and analyzed by TEM presented a cyst wall type compatible with S. miescheriana, and one cyst presented an ultrastructure compatible with S. suihominis. The latter came from a sample that also contained S. miescheriana cysts, indicating that the animal was co-infected. This is the first study that provides infection rates and describes and identifies morphological and molecular features of Sarcocystis spp. cysts in wild boars from South America.
肉孢子虫属是细胞内原生动物寄生虫，具有 obligatory heteroxenous 生命周期。本研究的目的是通过光学显微镜、透射电子显微镜及分子特征鉴定阿根廷野猪肌肉中的肉孢子虫属。对240头野猪的膈肌、舌、咬肌、肋间肌、心脏和前肢的肌肉样本进行了分析。在这些动物中，48.3%（116/240）通过光学显微镜检查发现有肉孢子囊呈阳性，而45.8%（110/240）通过靶向18S rRNA片段的PCR检测肉孢子虫属呈阳性。这些样本进行了猪人肉孢子虫细胞色素c氧化酶亚基I（coxI）基因的特异性PCR检测，其中3.6%（4/110）为弱阳性。遗憾的是，序列分析结果不明确。这可能与样本中猪人肉孢子虫囊的潜在低载量有关，或者与引物与南美猪人肉孢子虫序列的不完全匹配有关。17个单个肉孢子囊通过PCR检测18S rRNA片段呈阳性，其序列彼此之间以及与先前报道的米氏肉孢子虫序列显示出99.75 - 100%的同一性。从11个肌肉样本中收集并通过透射电子显微镜分析的总共21个囊肿呈现出与米氏肉孢子虫相容的囊壁类型，并且一个囊肿呈现出与猪人肉孢子虫相容的超微结构。后者来自一个也含有米氏肉孢子虫囊肿的样本，表明该动物受到了混合感染。这是第一项提供感染率并描述和鉴定南美野猪中肉孢子虫属囊肿的形态和分子特征的研究。
