miRNome profiling of extracellular vesicles in severe COVID-19 patients and identification of predictors of mortality.

BACKGROUND: Extracellular vesicles (EVs), containing microRNAs (miRNAs) and other molecules, play a central role in intercellular communication, especially in viral infections caused by SARS-CoV-2. This study explores the miRNA profiles in plasma-derived EVs from severe COVID-19 patients referred to controls, identifying potential mortality miRNA predictors. METHODS: A prospective study was carried out, including 36 severe COVID-19 patients and 33 non-COVID-19 controls. EVs-derived miRNAs were sequenced, and bioinformatics and differential expression analysis between groups were performed. The plasma miRNA profile of an additional cohort of severe COVID-19 patients (n=32) and non-COVID-19 controls (n=12) was used to compare with our data. Survival analysis was used to identify potential mortality predictors among the SDE miRNAs in EVs. RESULTS: Severe COVID-19 patients showed 50 significantly differentially expressed (SDE) miRNAs in plasma-derived EVs. These miRNAs were associated with pathways related to inflammation and cell adhesion. Fifteen of these plasma-derived EVs miRNAs were also SDE in the plasma of severe patients vs controls. Two miRNAs, hsa-miR-1469 and hsa-miR-6124, were identified as strong mortality predictors with an área under the ROC Curve (AUC) of 0.938. CONCLUSION: : This research provides insights into the role of miRNAs found within EVs in severe COVID-19 and their potential as clinical biomarkers for mortality.

HCV Cure With Direct-Acting Antivirals Improves Liver and Immunological Markers in HIV/HCV-Coinfected Patients.

Hepatitis C virus (HCV) cure after all-oral direct-acting antiviral (DAA) therapy greatly improves the liver and immune system. We aimed to assess the impact of this HCV clearance on immune system-related markers in plasma and the gene expression profile in human immunodeficiency virus (HIV)/HCV-coinfected patients with advanced cirrhosis. We performed a prospective study on 33 HIV/HCV-coinfected patients at baseline and 36 weeks after the sustained virological response. Gene expression was evaluated by RNA-seq analysis on peripheral blood mononuclear cells (PBMCs) and plasma biomarkers by multiplex immunoassays. We found a decrease in plasma biomarkers (PD1, PDL1, CXCL10, CXCL8, IL12p70, IL10, and TGFß) and liver disease markers (stiffness measurement (LSM), hepatic venous pressure gradient (HVPG), and transaminases, among others). Furthermore, decreased plasma levels of CXCL8, CXCL10, IL10, and PD1 were associated with reduced LSM values. We also found two upregulated (HAS1 and IRG1) and 15 downregulated (CXCL11, CCL8, CCL7, CCL2, ADARB2, RRAD, MX1, SIGLEC1, IFI44L, IFI44, IFI27, IFI6, IFIT3, IFIT1B, and IFIT1) genes at the end of follow-up, all interferon-stimulated genes (ISGs) grouped into four pathways ("cytokine-cytokine receptor interaction", "viral protein interaction with cytokine and cytokine receptor", "chemokine signaling pathway", and "hepatitis C"). Additionally, the decrease in most of these ISGs was significantly related to reduced LSM and HVPG values. In conclusion, HIV/HCV-coinfected patients with advanced-HCV-related cirrhosis who eradicated HCV following DAA therapy exhibited an improvement in liver disease markers and a significant decrease in plasma biomarkers and gene expression related to antiviral/inflammatory response, particularly in levels of several chemokines and ISGs.