Departamento de Genética, Facultad de Medicina, Universidad de la República, Montevideo, Uruguay.
Sección Bioquímica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.
Parasitology. 2022 Sep;149(11):1505-1514. doi: 10.1017/S0031182022000956. Epub 2022 Jul 5.
The phylum Platyhelminthes shares a unique population of undifferentiated cells responsible for the proliferation capacity needed for cell renewal, growth, tissue repair and regeneration. These cells have been extensively studied in free-living flatworms, whereas in cestodes the presence of a set of undifferentiated cells, known as germinative cells, has been demonstrated in classical morphology studies, but poorly characterized with molecular biology approaches. Furthermore, several genes have been identified as neoblast markers in free-living flatworms that deserve study in cestode models. Here, different cell types of the model cestode were characterized, identifying differentiated and germinative cells. Muscle cells, tegumental cells, calcareous corpuscle precursor cells and excretory system cells were identified, all of which are non-proliferative, differentiated cell types. Besides those, germinative cells were identified as a population of small cells with proliferative capacity . Primary cell culture experiments in Dulbecco's Modified Eagle Medium (DMEM), hydatid fluid and hepatocyte conditioned media in non-reductive or reductive conditions confirmed that the germinative cells were the only ones with proliferative capacity. Since several genes have been identified as markers of undifferentiated neoblast cells in free-living flatworms, the expression of and genes was analysed by qPCR and hybridization, showing that the expression of these genes was stronger in germinative cells but not restricted to this cell type. This study provides the first tools to analyse and further characterise undifferentiated cells in a model cestode.
扁形动物门拥有独特的未分化细胞群体，这些细胞负责增殖能力，以实现细胞更新、生长、组织修复和再生。这些细胞在自由生活的扁形动物中得到了广泛研究，而在绦虫中，经典形态学研究已经证明存在一组未分化细胞，即生殖细胞，但用分子生物学方法对其特征的研究还很不完善。此外，在自由生活的扁形动物中已经鉴定出一些作为成体干细胞标记的基因，这些基因值得在绦虫模型中进行研究。在这里，我们对模型绦虫的不同细胞类型进行了特征描述，鉴定出了分化细胞和生殖细胞。鉴定出了肌肉细胞、表皮细胞、钙颗粒前体细胞和排泄系统细胞，这些都是非增殖的分化细胞类型。除此之外，还鉴定出生殖细胞是一群具有增殖能力的小细胞。在非还原或还原条件下，在 Dulbecco's Modified Eagle Medium (DMEM)、包虫液和肝细胞条件培养基中进行的原代细胞培养实验证实，生殖细胞是唯一具有增殖能力的细胞。由于在自由生活的扁形动物中已经鉴定出一些基因作为未分化成体干细胞的标记，因此我们通过 qPCR 和原位杂交分析了 和 基因的表达情况，结果表明这些基因在生殖细胞中的表达更强，但不限于这种细胞类型。本研究提供了分析和进一步研究模型绦虫中未分化细胞的第一个工具。
