Published in Nature Communications, the research looked at people who were exposed to the virus early on during the pandemic. The researchers found that T-cells — a type of white blood cell that helps protect the body from infection — from common cold coronavirus may be able to provide protection against Covid.
“Being exposed to SARS-CoV-2 virus doesn’t always result in infection, and we’ve been keen to understand why,” Rhia Kundu, PhD, the lead study author from Imperial’s National Heart and Lung Institute, said in a statement.
In a study involving 52 unvaccinated people who lived with someone who had just tested positive for the virus, the research found that those who did not catch the virus had significantly higher levels of T-cells than people who did get infected.
“Our study provides the clearest evidence to date that T cells induced by common cold coronaviruses play a protective role against (Covid) infection,” Professor Ajit Lalvani, senior author of the study, said.
He added, “These T cells provide protection by attacking proteins within the virus, rather than the spike protein on its surface.”
“New vaccines that include these conserved, internal proteins would, therefore, induce broadly protective T-cell responses that should protect against current and future SARS-CoV-2 variants,” Lalvani said.
Researchers, however, emphasise that no one should rely on this research alone and people should get vaccinated to protect themselves from the virus.
According to Dr Saad Hafeez Usmani, Consultant-Internal Medicine, Manipal Hospital, Varthur Road, “This data could be beneficial for the next steps of Covid vaccine development with a focus on internal proteins for a lasting protection as T-cells response persists longer than antibody response that fades within a few months of vaccination.”
However, Dr Usmani said relying only on this study is not advisable. “Although it’s an important discovery, due to a small sample size and no ethical diversity, it should be considered only one form of protection and to rely only on it is not advisable.”