The coronavirus seems to target specific cells in body

AS THE COVID-19 pandemic continues, our key workers in the NHS and other services strive to treat sufferers from the coronavirus, limit its spread and keep us safe. Scientists around the world are working flat out to discover how the virus causes people to feel so ill.

Researchers from the Massachusetts Institute of Technology (MIT) and Harvard University have just revealed that they have identified specific types of cells that appear to be targeted by the coronavirus. This is very encouraging, since at the moment we have no drug against the virus.

They have found cells in the nasal passages, the lungs and the intestine that express two proteins that help the virus enter human cells.

These specific cells express RNA for both of these proteins far more than other cells.

The coronavirus resembles a miniature World War Two sea mine. Not long after the outbreak began scientists discovered that these spikes are made of a protein that is able to bind to a specific receptor site on the surface of cells.

A human protein, an enzyme called TMPRSS2, helps to activate the coronavirus spike protein, which opens the cell to let the virus inside.

The researchers have now been able to use a technique called single cell RNA sequencing to locate which cells in the body are specifically targeted by the virus.

They found that the goblet cells which produce mucous in the nasal passages express RNA for both of these proteins.

In the lungs, they found that cells called type-II pneumocytes also express RNA for them.

These cells line and keep open the alveoli, the tiny air sacs inside the lungs. In the intestine, they found that cells called absorptive enterocytes, which are responsible for absorbing certain nutrients similarly express these two proteins more than any other gut cells.

The researchers suggest that the coronavirus may have evolved to take advantage of host cells’ natural defence mechanisms, effectively hijacking these two proteins on these cells to get into the cells.

The significance of this breakthrough is that if these cells are targeted by the virus, they give scientists targets for the development of new drugs to treat this dreadful disease, or to help them test existing drugs like anti-malarials that could be repurposed.