A small study from the Imperial College London suggests that the body’s defense against common cold coronaviruses may provide some protection against COVID-19, providing a potential direction for upcoming vaccine development.
The research published in Nature Communications on Monday found that people with higher T cell levels from previous coronavirus infections like the common cold were less likely to contract COVID-19.
The virus that sparked the pandemic is a kind of coronavirus, while other coronaviruses spark other illnesses including some common colds.
By analyzing blood samples from 52 participants who lived with someone with confirmed COVID-19 in September 2020, researchers determined that there were “significantly higher levels” of pre-existing T cells after common cold coronaviruses among the 26 people who did not contract COVID-19.
Still, the researchers emphasized that vaccines still offer the best protection against the virus that’s killed millions worldwide.
"While this is an important discovery, it is only one form of protection, and I would stress that no one should rely on this alone,” lead author Rhia Kundu said. “Instead, the best way to protect yourself against COVID-19 is to be fully vaccinated, including getting your booster dose.”
But the results could help improve the shots’ effectiveness against current and future variants. The T cells researched in the study offer protection by focusing on internal proteins within the COVID-19 virus, instead of spike proteins.
The current vaccines, while effective, target the spike proteins located on the surface of the virus that are more likely to mutate than internal proteins, including in the omicron strain. The data suggests the next step of COVID-19 vaccine development should focus on internal proteins.
"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,” senior author Ajit Lalvani said in a release.
The researchers acknowledged that the study’s small sample size and lack of ethnic diversity, with the vast majority of participants being of white European ethnicity, present limitations for the research.
