Bezerra Marcos Alexandre, Pereira Luiz Miguel, Baroni Luciana, Yatsuda Ana Patrícia
Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av Do Café, S/n, 14040-903, Ribeirão Preto, SP, Brazil.
Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Av Do Café, S/n, 14040-903, Ribeirão Preto, SP, Brazil.
Exp Parasitol. 2019 Sep;204:107731. doi: 10.1016/j.exppara.2019.107731. Epub 2019 Jul 30.
Neospora caninum is an obligate intracellular parasite related to cases of abortion and fertility impairment in cattle. The control of the parasite still lacks an effective protective strategy and the understanding of key mechanisms for host infection might be crucial for identification of specific targets. There are many proteins related to important mechanisms in the host cell infection cycle such as adhesion, invasion, proliferation and immune evasion. The surface proteins, especially SRS (Surface Antigen Glycoprotein - Related Sequences), have been demonstrated to have a pivotal role in the adhesion and invasion processes, making them potential anti-parasite targets. However, several predicted surface proteins were not described concerning their function and importance in the parasite life cycle. As such, a novel SRS protein, NcSRS57, was described. NcSRS57 antiserum was used to detect SRS proteins by immunofluorescence in parasites treated or not with phosphatidylinositol-specific phospholipase C (PI-PLC). The treatment with PI-PLC also allowed the identification of NcSRS29B and NcSRS29C, which were the most abundant SRS proteins in the soluble fraction. Our data indicated that SRS proteins in N. caninum shared a high level of sequence similarity and were susceptible to PI-PLC. In addition, the description of the SRS members, regarding abundance, function and immunogenicity will be useful in guiding specific methods to control the mechanism of adhesion and invasion mediated by these surface proteins.
犬新孢子虫是一种专性细胞内寄生虫，与牛的流产和生育能力受损病例有关。对该寄生虫的控制仍然缺乏有效的保护策略，而了解宿主感染的关键机制可能对确定特定靶点至关重要。在宿主细胞感染周期中存在许多与重要机制相关的蛋白质，如黏附、入侵、增殖和免疫逃避。表面蛋白，尤其是SRS（表面抗原糖蛋白相关序列），已被证明在黏附和入侵过程中起关键作用，使其成为潜在的抗寄生虫靶点。然而，一些预测的表面蛋白在寄生虫生命周期中的功能和重要性尚未得到描述。因此，描述了一种新的SRS蛋白，即NcSRS57。使用NcSRS57抗血清通过免疫荧光检测经磷脂酰肌醇特异性磷脂酶C（PI-PLC）处理或未处理的寄生虫中的SRS蛋白。PI-PLC处理还鉴定出了NcSRS29B和NcSRS29C，它们是可溶性部分中最丰富的SRS蛋白。我们的数据表明，犬新孢子虫中的SRS蛋白具有高度的序列相似性，并且对PI-PLC敏感。此外，对SRS成员在丰度、功能和免疫原性方面的描述将有助于指导控制这些表面蛋白介导的黏附和入侵机制的具体方法。
