Could antibodies from SARS help fight Covid-19?
- There is more to be discovered about SARS-CoV-2 antibodies and how they can protect us.
- Previous research has shown that plasma can potentially treat Covid-19.
- Researchers are currently exploring antibodies to a previous coronavirus, SARS-CoV, to speed up the process.
As the fight against the Covid-19 pandemic intensifies, experts are trying various options, including the use of antibodies created in people after infection with the SARS-CoV-2 virus.
Right now, scientists are still not sure about the extent of immunity provided by SARS-CoV-2 antibodies. Even though the body does respond to the virus by creating antibodies, experts are still divided on how long these antibodies can provide immunity. It is believed that this immunity may be short-lived, which will require booster vaccines or follow-up treatments.
Now, research published in Nature shows the evidence needed to consider in the development of antibody immunotherapy. To help with this, the researchers went back to investigate antibodies from a person infected with SARS (severe acute respiratory syndrome), which was also caused by a coronavirus.
The role of antibodies in the fight against a virus
Coronavirus stems from the word "corona", which means "crown", referring to the spikes on the surface of the virus. These spikes help the virus to adhere to various cells in the body, where it then binds to a protein on the cell’s surface, called the ACE2 receptor.
The ideal antibodies to help fend off SARS-CoV-2 in the body would have to be able to recognise these viral spikes and block the virus’s ability to bind to the ACE2 receptors. These types of antibodies would be known as "neutralising” antibodies".
Can antibodies be used as a Covid-19 treatment?
Even though scientists still have a lot to discover about antibodies, it has been shown so far that plasma from those who were previously infected with Covid-19 could be used as a treatment option.
But according to the researchers, the treatment option of using antibodies can be made more "high-tech" by manipulating antibody-producing B-cells taken from the blood of people who have had Covid-19 or other diseases caused by a coronavirus.
Each of these B-cells makes its own unique antibodies, and clonal populations of a B cell of interest can be used to generate an identical pool of the desired antibody that is needed for treatment, the researchers stated in the study.
Going back in time
In an effort to help accelerate the harvesting of those B-cells, the researchers decided to go back and use samples of B-cells from a person who had had the coronavirus SARS-CoV that caused SARS in 2003.
This virus is quite similar to SARS-CoV-2 in the sense that it also caused respiratory distress, and the researchers are hoping that these antibodies could also help neutralise SARS-CoV-2. Their exact methodology and the results are explained here.
The researchers had a headstart in their current investigation by already having used existing antibodies – they now should have more B-cell populations to mine, according to the article.
They will first test individual antibodies and antibody cocktails in animals to see if they do offer protection and a neutralising effect against SARS-CoV-2. Then, clinical trials will be conducted to see if such a treatment would be safe and effective in humans.
With this accelerated step, the time needed for research could be as little as five to six months.