PCV2 infects porcine placental trophoblast cells and remodels the lncRNA-mRNA regulatory network.

Porcine Circovirus type 2 (PCV2) is recognized as the smallest animal virus known to cause reproductive failure in sows and can be vertically transmitted through the placenta to infect piglets, leading to Postweaning Multisystemic Wasting Syndrome (PMWS). Long non-coding RNAs (lncRNAs) are involved in numerous physiological and pathological processes, closely related to trophoblast cell invasion, placental development, and fetal growth restriction. To investigate whether PCV2 can infect porcine placental trophoblast cells and to characterize the lncRNA-mRNA expression profiles following infection, this study infected porcine placental trophoblast cells with PCV2 and conducted comparative transcriptome analysis between infected and uninfected cells, followed by qPCR validation of sequencing results. The study confirmed that PCV2 successfully infects porcine placental trophoblast cells, identifying 1714 differentially expressed mRNAs and 254 differentially expressed lncRNAs post-infection. Functional enrichment analysis demonstrated that PCV2 infection modulates the growth and immune responses of porcine placental trophoblast cells. Furthermore, target genes of the differentially expressed lncRNAs were identified through colocalization and coexpression analyses. GO enrichment analysis based on the target genes of the differentially expressed lncRNAs showed abundant transcription in biological processes such as metabolism and regulation of ER-to-Golgi transport, and pathway analysis indicated that PCV2 infection impacts cell cycle, TNF, and IL-17 signaling pathways. This study reveals PCV2's infectivity in porcine placental trophoblast cells, provides the lncRNA-mRNA expression profiles post-infection, and offers critical insights for understanding PCV2's impacts and advancing lncRNA research.