A group of researchers from the Institute of Health Carlos III (ISCIII) in Spain, presented a poster at the annual meeting for the International Society of Extracellular Vesicles (ISEV), which analyzed exosome RNA content for identification of new liver disease biomarkers. Using high throughput NGS, the group identified multiple liver-specific miRNAs from plasma exosomes of patients who are coinfected with HIV and HCV.

Patients who are coinfected with HIV and HCV are highly susceptible to liver disease, which is the most common cause of death for these patients. Monitoring liver disease progression in HIV/HCV coinfected patients is critical to determine prognosis and treatment. Identification of specific biomarkers, such as miRNAs from exosomes, can aid in predicting the clinical disease progression for these patients. Exosomal miRNAs play an integral role in the antiviral response against HCV and HIV as well as reflect modifications in the liver that can be indicative of disease state. Plasma samples were collected from the HCV/HIV coinfected patients and exosomes were enriched using a variety of purification methods. The exosomal RNA  was then purified using two commercially available kits and the RNA was sequenced on Illumina HiSeq platform.  

The group was able to identify 243 miRNAs which mainly belong to fatty acid metabolism and cell signaling pathways (using miRNpath v.3 for pathway identification). Most of the miRNAs that were highly abundant (such as -let-7a-5p, miR-21-5p, miR-22-3p and miR-199a-3p) were found to be upregulated in liver disease. One of the most detected miRNAs was the hsa-miR-122-5p, whose expression is specific to the liver and plays an important positive role in HCV infection. The group concluded that these liver-specific miRNAs are excellent molecules to focus further research for liver disease prognosis and evolution.

This study utilized Norgen's Plasma/Serum Exosome and Free-Circulating RNA Isolation Mini Kit (Cat. 59500)