Novel coronavirus uses a surprising pathway to exit infected cells

The new coronavirus uses a surprising pathway to exit infected cells and go on to infect others, researchers have discovered.

It hijacks a cell structure called the lysosome, which is normally where cellular trash goes to be destroyed. But the virus uses lysosomes as escape hatches, the researchers report in Cell.

“To my knowledge coronavirus is one of 2 or 3 viruses to do this, and certainly the only enveloped virus,” said coauthor Nihal Altan-Bonnet of the National Heart Lung and Blood Institute, referring to viruses that have a membrane surrounding their genetic material.

“All other enveloped viruses … use other pathways for cell-to-cell spread,” Altan-Bonnet added. These include influenza, hepatitis C, Dengue, Zika, West Nile and Ebola.

When lysosomes degrade bacteria and viruses into little pieces, she explained, “these little pieces get presented on the surface of the cell to alert the immune system” to the invaders’ presence.

By using the trash disposal system of the cell to get out, the new coronavirus disables the lysosome and disrupts alerting the immune system, she said.

“We believe our discovery of the pathway used by coronaviruses to get out of cells will be fundamental to our understanding of how these viruses wreak havoc on our body, in particular our immune system.”