Host-derived miRNAs as novel regulators of porcine reproductive and respiratory syndrome virus replication: Mechanistic insights and therapeutic potentials.

Abstract

Porcine reproductive and respiratory syndrome virus (PRRSV) continues to pose a major and persistent threat to the global swine industry, largely owing to its high mutation rate and ability to evade host immune responses. MicroRNAs (miRNAs), a class of endogenous small non-coding RNAs approximately 22 nucleotides long, play a pivotal role in post-transcriptional gene regulation by binding to the 3' untranslated regions (UTRs) of target mRNAs. In recent years, a wealth of studies has explored the RNA-level interplay between the host and PRRSV during infection, highlighting the dual roles that miRNAs play in modulating PRRSV replication. This review offers a comprehensive and up-to-date summary of the current body of knowledge regarding host-derived miRNAs implicated in PRRSV infection, with a focus on 38 miRNAs identified to date. Among these, 27 miRNAs have been shown to exhibit antiviral properties, whereas 11 have been reported to promote viral replication. Furthermore, we explore the potential applications of miRNAs in antiviral strategies, including RNAi-based therapeutic approaches, miRNA-guided diagnostic tools, and miRNA-based live attenuated vaccines. These insights not only deepen our understanding of PRRSV-host interactions but also highlight the potential of miRNA biology for developing new approaches to disease control.