MicroRNA-based strategy to mitigate the risk of gain-of-function influenza studies

Abstract

Recent gain-of-function studies in influenza A virus H5N1 strains revealed that as few as three amino-acid changes in the hemagglutinin protein confer the capacity for viral transmission between ferrets1, 2. As transmission between ferrets is considered a surrogate indicator of transmissibility between humans, these studies raised concerns about the risks of gain-of-function influenza A virus research. Here we present an approach to strengthen the biosafety of gain-of-function influenza experiments. We exploit species-specific endogenous small RNAs to restrict influenza A virus tropism. In particular, we found that the microRNA miR-192 was expressed in primary human respiratory tract epithelial cells as well as mouse lungs but absent from the ferret respiratory tract. Incorporation of miR-192 target sites into influenza A virus did not prevent influenza replication and transmissibility in ferrets, but did attenuate influenza pathogenicity in mice. This molecular biocontainment approach should be applicable beyond influenza A virus to minimize the risk of experiments involving other pathogenic viruses.

Insights into RNA Interference as Antiviral Defense

“…The group of human miRNAs including miR-28, miR-125b, miR-150, miR-223 and miR-382 targets 3' end of HIV-1 mRNAs and significantly decrease HIV-1 replication in n resting CD4 + T cells [40]. Similarly, mir-let-7c, mir-192 and mir-142 inhibit influenza virus replication [41][42][43].…”

Investigating Influenza A Virus Infection: Tools To Track Infection and Limit Tropism

“…While discussions of safety and the rationale for aTRIP experiments are critical, the need for a resolution is paramount to allow the work the field deems important to continue. Species-specific miRNAs offer an enticing way to mitigate potential safety concerns involved in the study of pathogenic, transmissible IAVs (19). Small RNA deep sequencing was again employed to discover a species-specific miRNA, miRNA-192, expressed in primary human respiratory tract epithelial cells and mouse lungs but absent from the ferret respiratory tract, the model system used to study virus transmission (19).…”

“…Species-specific miRNAs offer an enticing way to mitigate potential safety concerns involved in the study of pathogenic, transmissible IAVs (19). Small RNA deep sequencing was again employed to discover a species-specific miRNA, miRNA-192, expressed in primary human respiratory tract epithelial cells and mouse lungs but absent from the ferret respiratory tract, the model system used to study virus transmission (19). Mice infected with miR-192-targeted IAV demonstrated less morbidity and mortality than those infected with the control virus.…”

“…Mice infected with miR-192-targeted IAV demonstrated less morbidity and mortality than those infected with the control virus. Importantly, infection of ferrets resulted in normal virus replication and aerosol transmission to secondary hosts (19). The inclusion of this method, in addition to standard physical safety measures, could allow researchers to study potential aTRIP IAV strains in the ferret model with less risk to human health.…”

Molecular biocontainment for the flu

“…1 The microRNA-based containment strategy provides a safeguard in case of accidental release or intentional misuse of viruses used in influenza research and could help study how pandemics originate, although the stability of the engineered strain and how well it recapitulates wild-type virus biology have yet to be thoroughly determined.…”