Scientists turn to new weaponry in pandemic war while awaiting vaccines

The treatment prevents the immune system from turning against healthy cells and damaging organs

19 October 2020 - 20:00
By tanya farber AND Tanya Farber
Scientists are figuring out the intricate details of Covid-19's attack mode.
Image: KATERYNA KOM/123RF THE FIGHT GOES ON Scientists are figuring out the intricate details of Covid-19's attack mode.

The world is waiting with bated breath for a vaccine against Covid-19.

But researchers have now also turned their attention to another weapon in the arsenal: preventing severe organ damage by blocking a protein that enables the immune system to turn against healthy cells.

A recent study at Johns Hopkins Medicine found that “by blocking a specific protein in a biological pathway”, they could possibly prevent Covid-19 infection “and keep the virus from misdirecting the immune system against health cells and organs”.

The scientists said we “already know there are spike proteins on the surface of the pathogen that make it look like a medieval mace” and that this is how the virus attaches itself to cells it targets for infection.

The spikes “first grab hold of a … molecule found on the surface of cells in the lungs, blood vessels and smooth muscle making up most organs”.

It then uses another protein “as its doorway” into the cell and basically disarms that protein’s “normal function”, which is to “regulate the chemical signals that trigger inflammation and keep the immune system from harming healthy cells”.

Without this protection, cells in the lungs, heart, kidneys and other organs can be destroyed by the defence mechanism nature intended to safeguard them.

Senior author on the study Robert Brodsky said: “The goal of our study was to discover how the virus activates this pathway and to find a way to inhibit it before the damage happens.”

In a series of experiments, the Johns Hopkins researchers used normal human blood serum and three subunits of the Covid-19 spike protein to discover exactly how the virus hijacks the immune system and endangers normal cells. 

From there, the team found that by blocking another type of protein that works “upstream” from the one that protects the immune system, they were able to “stop the destructive chain of events triggered” by the virus.

It’s still early days, but what makes the discovery “even more exciting”, say the researchers, is that there may already be drugs in development and testing for other diseases that can do the required blocking. 

The researchers hope that their work will encourage more study into the potential use against Covid-19 of complement-inhibiting drugs already in the pipeline for other diseases.