Early Brucella abortus infection reshapes the exosomal lncRNA cargo of macrophages and highlights putative immunoregulatory pathways

Brucella abortus is an intracellular pathogen that profoundly alters macrophage responses, but the contribution and extracellular distribution of long non-coding RNAs (lncRNAs) during infection remain poorly characterized. Here, we characterized the exosomal lncRNA landscape of B. abortus -infected RAW 264.7 macrophages and applied an integrated bioinformatic framework to prioritize candidate lncRNAs and their potential functional contexts. Exosomes were isolated from infected and control macrophages at 8 h post-infection, and their RNA content was analyzed by high-throughput sequencing. Differential expression analysis identified 83 lncRNAs with altered expression, with most showing reduced expression in exosomes from infected cells. Functional enrichment analysis of protein-coding genes located within ±250 kb of the differentially expressed lncRNAs generated associations with immune-related processes, including antigen presentation and cytotoxicity, as well as ion transport, lipid metabolism, and lymphocyte-related processes. A complementary Enrichr analysis provided complementary immune-related signals, although these did not remain significant after multiple-testing corrections. Malat1 , Neat1 , and Gas5 were selected for RT-qPCR validation and showed expression patterns consistent with sequencing. AlphaFold 3 predicted Snu13 as a potential interactor of the three candidate lncRNAs, providing a hypothesis for future experimental investigation but not establishing a role in exosomal RNA sorting. Overall, these findings provide a transcriptomic resource and computational framework for prioritizing exosomal lncRNAs associated with B. abortus infection and support further investigation of EV-associated lncRNA loading mechanism and their potential functional relevance.