Previous Common Cold May Protect From COVID-19
Common colds are by all accounts are a challenging time for a person. However, the new research suggests that previous common cold may protect from COVID-19. The infectious diseases experts at the University of Rochester Medical Centre authored a study which suggests that immunity developed against Covid-19 is likely to stay there for long-even maybe for a lifetime.
The study published in mBio, claimed that if you have had a common cold in past it gives you an immunity in future against COVID-19. The study is the first off to claim that the COVID –19 virus activates memory B cells. These are long-lasting immune cells that detect pathogens, activates antibodies to kill them and remember these pathogens for the future. The next time pathogens infiltrate the body; the immune system activates on its own even faster than before it used to be.
Besides, the memory B cells can endure for decades. Therefore, it protects the survivor of a particular infection for a long time against the same pathogen. However, further research is required to endorse this study.
The study is also the inaugural in reporting that memory B cells that have attacked the cold-causing family of coronavirus also remember the SARS-CoV-2 (COVID-19). The authors have a strong belief that this recognition
can help to defend the covid-19 by having some degree of pre-existing immunity in people formerly infected by a common cold.
“When we looked at blood samples from people who were recovering from COVID-19, it looked like many of them had a pre-existing pool of memory B cells that could recognize SARS-CoV-2 and rapidly produce antibodies that could attack it,” said lead study author Mark Sangster, Ph.D., a research professor of Microbiology and Immunology at URMC.
Sangster’s findings rely on an analysis of blood samples from 26 people who have recovered from mild to moderate COVID-19 to 21 healthy donors whose samples were collected six to 10 years ago. From those samples, study authors find the levels of memory B cells and antibodies that target specific parts of the virus protein (Spike protein). A protein which is a part of all coronaviruses and is compelling for the viruses when infecting the cells.
The Spike protein is divergent and functions differently in each coronavirus. Although, one of its components, the S2 subunit, continues to be the same across all types of viruses. The memory B cells are not able to differentiate between Spike S2 subunits of different coronaviruses. This is the primary factor that helps the memory B cells to act indiscriminately against all coronaviruses. For now, somewhat the researcher’s claims are valid for beta-coronaviruses-a subclass inclusive of two cold-causing viruses along with SARS, MERS and SARS-CoV-2.
A lapse in this study is that it doesn’t show the level of protection which cross-reactive memory B cells provides and how it affects the patient.
“That’s next,” said David Topham, Ph.D., the Marie Curran Wilson and Joseph Chamberlain Wilson Professor of Microbiology and Immunology at URMC, who runs the lab that conducted this work. “Now we need to see if having this pool of pre-existing memory B cells correlates with milder symptoms and shorter disease course — or if it helps boost the effectiveness of COVID-19 vaccines.”
