Researchers from the University of Barcelona and IQAC–CSIC have developed a novel therapeutic tool aimed at inhibiting the proliferation of SARS-CoV-2, the virus responsible for COVID-19.

This study introduces Polypurine Reverse Hoogsteen Hairpins (PPRH) as a groundbreaking method to slow the virus's replication, marking the first time this approach has been documented in scientific literature.

PPRHs are short DNA molecules designed to bind specifically to RNA sequences, targeting critical regions of the SARS-CoV-2 genome.

Two types of PPRH—CC1-PPRH and CC3-PPRH—have been identified as effective in blocking viral activity by binding to essential RNA sequences involved in virus replication and infection.

The CC1-PPRH targets the RNA region encoding the viral replicase enzyme, while the CC3-PPRH binds to the Spike protein coding region, which is crucial for the virus's ability to infect human cells.

In vivo validation of this therapeutic technique was conducted using laboratory animals expressing the human ACE2 receptor, alongside in vitro studies on Vero E6 cells, which are susceptible to SARS-CoV-2.

Results from these studies indicate that both CC1-PPRH and CC3-PPRH are effective in inhibiting virus replication in the tested models.

The findings highlight the versatility of PPRHs, extending their applications from diagnostics to therapeutic interventions, with previous research indicating their potential for detecting RNA viruses more efficiently than traditional PCR methods.

PPRHs have also shown promise in cancer therapy, capable of silencing cancer-related genes and facilitating gene editing techniques.

This research has broader implications beyond COVID-19, as it may also aid in combating other viral diseases lacking current treatments, such as Crimean-Congo hemorrhagic fever (CCHFV).

The research was published on December 3, 2024, in the Journal of Biological Chemistry, led by Carlos J. Ciudad and Verónica Noé, with contributions from multiple institutions.

The therapeutic technique has been validated in laboratory animals expressing the human ACE2 receptor and shown effective in Vero E6 cells, which are susceptible to SARS-CoV-2.