Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, 130062, China.
Beijing Hi-Tech Institute, Beijing, 100085, China.
Parasit Vectors. 2021 Mar 1;14(1):130. doi: 10.1186/s13071-021-04624-6.
Parasites of the genus Trichinella are the pathogenic agents of trichinellosis, which is a widespread and severe foodborne parasitic disease. Trichinella spiralis resides primarily in mammalian skeletal muscle cells. After invading the cells of the host organism, T. spiralis must elude or invalidate the host's innate and adaptive immune responses to survive. It is necessary to characterize the pathogenesis of trichinellosis to help to prevent the occurrence and further progression of this disease. The aims of this study were to elucidate the mechanisms of nurse cell formation, pathogenesis and immune evasion of T. spiralis, to provide valuable information for further research investigating the basic cell biology of Trichinella-infected muscle cells and the interaction between T. spiralis and its host.
We performed transcriptome profiling by RNA sequencing to identify global changes at 1, 3, 7, 10 and 15 days post-infection (dpi) in gene expression in the diaphragm after the parasite entered and persisted within the murine myocytes; the mice were infected by intravenous injection of newborn larvae. Gene expression analysis was based on the alignment results. Differentially expressed genes (DEGs) were identified based on their expression levels in various samples, and functional annotation and enrichment analysis were performed.
The most extensive and dynamic gene expression responses in host diaphragms were observed during early infection (1 dpi). The number of DEGs and genes annotated in the Kyoto Encyclopedia of Genes and Genomes and Gene Ontology databases decreased significantly in the infected mice compared to the uninfected mice at 3 and 7 dpi, suddenly increased sharply at 10 dpi, and then decreased to a lower level at 15 dpi, similar to that observed at 3 and 7 dpi. The massive initial reaction of the murine muscle cells to Trichinella infection steadied in the later stages of infection, with little additional changes detected for the remaining duration of the studied process. Although there were hundreds of DEGs at each time point, only 11 genes were consistently up- or downregulated at all 5 time points.
The gene expression patterns identified in this study can be employed to characterize the coordinated response of T. spiralis-infected myocytes in a time-resolved manner. This comprehensive dataset presents a distinct and sensitive picture of the interaction between host and parasite during intracellular infection, which can help to elucidate how pathogens evade host defenses and coordinate the biological functions of host cells to survive in the mammalian environment.
旋毛虫属寄生虫是旋毛虫病的病原体，旋毛虫病是一种广泛且严重的食源性寄生虫病。旋毛虫主要存在于哺乳动物的骨骼肌细胞中。在侵入宿主细胞后，旋毛虫必须逃避或使宿主的固有和适应性免疫反应失效才能存活。因此，有必要对旋毛虫病的发病机制进行研究，以帮助预防这种疾病的发生和进一步发展。本研究旨在阐明旋毛虫的滋养细胞形成、发病机制和免疫逃避的机制，为进一步研究旋毛虫感染的肌肉细胞的基本细胞生物学以及旋毛虫与宿主之间的相互作用提供有价值的信息。
我们通过 RNA 测序进行转录组谱分析，以鉴定寄生虫进入并在小鼠肌细胞内持续存在后 1、3、7、10 和 15 天感染（dpi）时膈肌中基因表达的全局变化；通过静脉注射新生幼虫感染小鼠。基因表达分析基于比对结果。根据不同样本中的表达水平确定差异表达基因（DEGs），并进行功能注释和富集分析。
在早期感染（1 dpi）时，宿主膈肌中观察到最广泛和最动态的基因表达反应。与未感染的小鼠相比，感染的小鼠在 3 和 7 dpi 时 DEGs 和京都基因与基因组百科全书和基因本体论数据库注释的基因数量显著减少，在 10 dpi 时突然急剧增加，然后在 15 dpi 时降至较低水平，与 3 和 7 dpi 时相似。在感染的后期，肌细胞对旋毛虫感染的剧烈初始反应趋于稳定，在研究过程的剩余时间内检测到的变化很小。尽管每个时间点都有数百个 DEGs，但只有 11 个基因在所有 5 个时间点始终上调或下调。
本研究中确定的基因表达模式可用于在时间分辨的方式下对旋毛虫感染肌细胞的协调反应进行特征描述。该综合数据集以一种独特而敏感的方式呈现了宿主与寄生虫在细胞内感染过程中的相互作用，有助于阐明病原体如何逃避宿主防御并协调宿主细胞的生物学功能以在哺乳动物环境中存活。
