Study suggests the eye as a point of SARS-CoV-2 infection

Investigators at Mount Sinai report that ocular cells may be infected directly by the virus, with the limbus especially susceptible.

Information about the SARS-CoV-2 virus has evolved continuously since the onset of the pandemic, and the most recent research conducted by researchers at Mount Sinai shows that ocular cells may be infected directly by the virus, with the limbus especially susceptible.

This is important because it recognizes a potential route of infection.

Investigators led by first author Anne Eriksen, PhD, and senior author Timothy Blenkinsop, PhD, both from the Department of Cell Development and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, emphasized that understanding the infectious mechanisms from all possible routes of entry is essential.

“While aerosol transmission is thought to be the primary route of spread, viral particles have been detected in ocular fluid suggesting the eye may be a vulnerable point of viral entry,” they stated.

The investigators conducted a study of adult human eyes obtained at autopsy of patients who had COVID-19. In an in vitro stem cell model, donor cells were infected with to SARS-CoV-2 and 24 hours later were studied to determine if the virus infected the ocular tissues and primary cells.

Analysis using RNA sequencing showed that the virus infected the ocular surface cells, especially the limbus. A protein associated with infection, i.e., ACE2, and an enzyme, TMPRSS2, that facilitates viral entry, were identified.

The study also found that expression of IFNβ, which has antiviral/antibacterial effects, was suppressed.

The authors suggested that protective eyewear can prevent infections developing through the eye, especially when traveling and in areas with poor ventilation.

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