MicroRNAs and the immune response to respiratory virus infections

Abstract

MicroRNAs (miRNAs) are small ssRNA molecules, which are involved in gene expression regulation at the post-transcriptional level. Their biological functions include modulation of both innate and adaptive immune response. miRNAs participate in the maintenance of the airway epithelial barrier and are also implicated in the modulation of antiviral defense in epithelial cells. The immune response to respiratory viruses such as rhinovirus, influenza virus and respiratory syncytial virus is associated with an altered expression of distinct miRNAs, and the changes in the miRNA expression profile in epithelial cells may contribute to the pathogenesis of both acute and chronic airway disease. Understanding the role of these small molecules in the antiviral immune response and identification of miRNAs target genes may help to clarify the mechanisms of virus-host interaction, and in the future may lead to development of new antiviral treatments.

Keywords::

• airway epithelium
• miRNA
• respiratory viruses
• toll-like receptors
• virus-encoded miRNAs

Acknowledgement

This paper was supported by a grant from the National Science Center (Maestro No. 2011/02/A/NZ5/00341).

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.

Key issues

• miRNAs are a class of small single-stranded RNA that is involved in the regulation of both innate and adaptive immune response to viral infections.

• Experimental infections with respiratory viruses seem to be associated with the virus and tissue-specific modulation of miRNA expression.

• Influenza A virus infection is associated with a specific miRNA profile in serum samples from infected individuals.

• Modulation of expression of specific miRNA may affect the development of the host response to viral infections, thus reducing virus infectivity and replication.

• Virus-encoded miRNAs interfere with antiviral response and miRNA-targeted virus attenuation may be useful for vaccine development.

• For the first time, miRNA-based therapy (Miravirsen, an miR-122 antagonist) has been shown to be effective for the management of viral (HCV) infection.