Researchers in Melbourne, Australia have uncovered a sneaky way COVID-19 spreads inside the body — and it turns out the virus piggybacks on the body's own garbage disposal system.
Scientists at La Trobe University and WEHI found that SARS-CoV-2 can hide inside tiny fragments of dying infected cells. These fragments, called apoptotic bodies or ApoBDs, are normally just cellular trash that the body cleans up. But when immune cells called macrophages swallow these fragments during their normal housekeeping routine, the virus hitches a ride into the cell.
"Our findings show the virus can bypass the usual entry route via ACE2 receptors to hide inside dying cell fragments, gaining access to immune cells during the body's 'clean-up' process," said Dr. Kha Phan, lead researcher and NHMRC Emerging Leadership Fellow at the La Trobe Institute for Molecular Science.
Once inside these immune cells, COVID-19 can spread between cells while disguised — and trigger a powerful inflammatory response that damages lung tissue. This explains why some people develop severe lung inflammation during COVID-19 infection.
The team, whose work was published in the journal Nature Communications, also found a potential fix. By blocking the formation of these virus-infected cell fragments using existing drugs called T-type calcium channel blockers, they were able to reduce lung damage, viral spread, and harmful inflammation in laboratory tests.
Co-senior author Professor Ivan Poon, an NHMRC chief investigator at La Trobe, said this discovery opens a completely different therapeutic approach that could complement existing antiviral drugs. Rather than targeting the virus directly, doctors might one day stop the pathways the virus uses to spread and cause damage.
The findings could also help explain how other respiratory viruses like influenza and RSV infect immune cells and drive severe inflammation, potentially improving treatments for future outbreaks.