Trypanosoma cruzi, which causes Chagas disease, is one of the most lacerating parasites in terms of health and social impacts. New approaches for its study and treatment are urgently needed since in more than 50 years only two drugs have been approved. Genetic approaches based on antisense oligonucleotides (AONs) are promising; however, to harness their full potential the development of effective carriers is paramount. Here, we report the use of an engineered virus-like protein C-B^K12 to transfect AONs into T. cruzi. Using gel electrophoresis, Dynamic Light Scattering, and atomic force microscopy, we found that C-B^K12 binds AONs and forms 10–25 nm nanoparticles (NPs), which are very stable when incubated in biological media, only releasing up to 25% of AON. Fluorescence microscopy and qPCR revealed that the NPs successfully delivered AONs into epimastigotes and reduced the expression of a target gene down to 68%. Importantly, the protein did not show cytotoxicity. The combination of high stability and capability to transfect and knock down gene expression without causing cell damage and death makes the protein C-B^K12 a promising starting point for the further development of safe and effective carriers to deliver AONs into T. cruzi for biological studies.

中文翻译：

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使用基于病毒样蛋白的纳米颗粒将反义 DNA 递送到致病寄生虫克氏锥虫中。

导致恰加斯病的克氏锥虫是对健康和社会影响最严重的寄生虫之一。由于 50 多年来仅批准了两种药物，因此迫切需要对其研究和治疗的新方法。基于反义寡核苷酸 (AON) 的遗传方法很有前景；然而，要充分发挥其潜力，开发有效的载体至关重要。在这里，我们报告了使用工程病毒样蛋白 CB ^K12将 AON 转染到T. cruzi。使用凝胶电泳、动态光散射和原子力显微镜，我们发现 CB ^K12结合 AONs 并形成 10-25 nm 纳米颗粒 (NPs)，在生物介质中培养时非常稳定，仅释放高达 25% 的 AON。荧光显微镜和 qPCR 显示 NPs 成功地将 AONs 传递到上鞭毛体并将目标基因的表达降低到 68%。重要的是，该蛋白质没有表现出细胞毒性。高稳定性和转染和敲低基因表达而不引起细胞损伤和死亡的能力相结合，使蛋白质 CB ^K12成为进一步开发安全有效的载体以将 AONs 传递到T. cruzi进行生物学研究的有希望的起点。