A multi-omics study to reveal host response pathways and develop novel biomarkers of severe pulmonary hemorrhagic syndrome in leptospirosis patients

Abstract

Leptospirosis is among the most widespread zoonoses worldwide. Severe pulmonary hemorrhagic syndrome (SPHS) represents a fatal complication in leptospirosis patients, with poor understanding of the underlying mechanisms and an effective biomarker. A nested case-control analysis of the blood specimens obtained from two previous multi-center cohorts was conducted. Candidate microRNAs were initially discovered through a global profiling of 800 serum microRNAs, then validated using real-time polymerase-chain reactions. We further conducted a multi-omics analysis incorporating data from transcriptomics and proteomics experiments to identify enriched pathways through which the newly identified microRNAs could regulate. A total of 28 SPHS and 140 nonSPHS patients were included. Serum microRNA profiling revealed distinct expression patterns between the two phenotypes. From the top 81 significantly expressed microRNAs, seven were selected for validation. Among these, miR-5010-3p and miR-147b-3p had area under the curve (AUC) values of 0.72 (95% CI: 0·62–0·81) and 0·66 (95% CI: 0·55–0·76) for discriminating SPHS. Notably, the two microRNAs could detect SPHS in patients who were yet to manifest chest radiograph shadows at serum collection, and in a subgroup of patients who were recruited on day 2 of illness or earlier, with consistent AUC values. Integrated gene-protein pathway enrichment analysis revealed numerous pathways involving immune responses. Among these, tumor necrosis factor signaling was the most significant with many of its member genes being targeted by miR-5010-3p or miR-147b-3p. MiR-5010-3p and miR-147b-3p are promising biomarkers of leptospirosis SPHS with robust predictability and biological relevance. Our findings should pave the way for developing miRNA-based prognostic assays and personalized therapeutic strategies for leptospirosis SPHS patients.