MicroRNAs (miRNAs) have a crucial role in regulating immune response against infectious diseases, showing changes early in disease onset and before the detection of the pathogen. Thus, we aimed to ...

Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) hijack the host exosomal machinery as an additional mechanism of infection and evasion of the immune system, modifying the small RNA (smRNA) cargo during infection. We characterized the surface epitopes of extracellular vesicles (EVs) from plasma HIV/HCV-coinfected patients and their smRNA cargo profile, by comparing different isolation procedures. Six EVs isolation procedures were compared: ultracentrifugation, and five different polyethylene glycol-based methods (commercial, combined with a column purification step and two custom); and two RNA commercial kits (phenol and non-phenol based) were used. High-throughput sequencing of smRNAs was performed. Exosomal surface epitopes were analyzed by the MACSPlex Exosome Kit. Four miRNAs displayed differences among protocols (hsa-miR-205-5p and hsa-let-7a/b/f-5p). The selection of RNA isolation kit impacted on the detection of miRNAs and other smRNAs, where the phenol-based RNA isolation kit performed acceptably. EVs surface was enriched with HLA-DR/DP/DQ, CD81, and CD8. There were three liver-specific miRNAs overexpressed (let-7a-5p, miR-21-5p and hsa-miR-122-5p), thus, EVs cargo might reflect liver disease evolution. Other smRNAs such as piwi-interacting RNAs were also detected for the first time. Custom polyethylene glycol precipitation-based methods combined with an RNA phenol-based kit yielded the higher number of smRNAs for EVs isolated from plasma HIV/HCV patients.

Patients with advanced cirrhosis are at high risk of developing clinically significant portal hypertension (CSPH). We analyzed the gene expression profile of peripheral blood mononuclear cells (PBMCs) from HIV/HCV coinfected patients to identify a gene expression signature of advanced cirrhosis with high risk for CSPH. We conducted a cross-sectional study on 68 patients. Liver stiffness measurement (LSM) was used to stratify patients into < 12.5 kPa (no cirrhosis, n = 19), 12.5 - 24.9 kPa (cirrhosis, n = 20), and ≥ 25 kPa (advanced cirrhosis with high risk for CSPH, n = 29). Besides, we further evaluated LSM < 25 kPa (n = 39) vs. ≥ 25 kPa (n = 29). Total RNA was extracted from PBMCs, and poly(A) RNA sequencing was performed. Two significant differentially expressed (SDE) transcripts were validated by quantitative PCR in a different cohort (n = 46). We found 60 SDE transcripts between patients with LSM < 12.5 kPa and ≥ 25 kPa. Partial least squares discriminant analysis showed that those 60 SDE transcripts collectively discriminated LSM ≥ 25 kPa, with an area under the receiver operating characteristic curve (AUROC) of 0.84. Eight genes had an AUROC ≥ 0.75 for LSM ≥ 25 kPa: five were positively associated with LSM values (SCAMP1, ABHD17B, GPR146, GTF2A1, and TMEM64), while three were inversely associated (ZFHX2-AS1, MDK, and STAG3L2). We validated the two SDE transcripts with the highest discrimination capacity in a different cohort, finding significant differences between < 25 kPa and ≥ 25 kPa (MDK (p = 0.006) and STAG3L2 (p = 0.021)). A gene expression signature of 60 transcripts was associated with advanced cirrhosis with high risk for CSPH in HIV/HCV coinfected patients.

Background: The myeloid-epithelial-reproductive tyrosine kinase (MERTK) is involved in hepatic steatosis, inflammation, and liver fibrosis. Here we evaluated the association between the MERTK rs4374383 single nucleotide polymorphism (SNP) and liver fibrosis progression in hepatitis C virus (HCV)-infected patients. Methods: We performed a retrospective study (repeated measures design) in 208 patients who had liver stiffness measurement (LSM), which was assessed using transient elastography. No patient had cirrhosis at baseline (LSM ≥ 12.5 kPa). Results: At baseline, 53.8% were male, the median age was 47.1 years, 13.5% reported a high intake of alcohol, 10.1% were prior injection drug users, 85.3% were infected with HCV genotype 1, and 22.6% had previously failed antiviral therapy (pegylated-interferon-alpha/ribavirin). During a median follow-up of 46.6 months, 26 patients developed cirrhosis. The rs4374383 G carriers had a higher risk of increasing LSM (adjusted arithmetic mean ratio (aAMR) = 1.14; p = 0.006) and a higher likelihood of having an increase in LSM greater than 5 kPa (ΔLSM ≥ 5 kPa) (adjusted odds ratio (aOR) = 2.37; p = 0.029), and greater than 7 kPa (ΔLSM ≥ 7 kPa) (aOR = 3.24; p = 0.032), after controlling for confounding. The SNP’s association with cirrhosis progression was close to statistical significance (aOR = 2.18; p = 0.070). Conclusions: MERTK rs4374383 A carriers had a lower risk of liver fibrosis progression than G carriers, supporting the hypothesis that this SNP seems to have a critical role in the pathogenesis of liver disease in HCV-infected patients.