A new small-scale study shows that high levels of T-cells from the common cold could potentially boost a person’s protection against COVID-19.
The study, published in Nature Communications, involved 52 individuals who had shared accommodation with someone with coronavirus. T-cells are an integral party of the body’s immune system, helping it respond to potential threats such as the common cold. When someone recovers from a cold, some T-Cells remain in the event of another virus. The study began in September 2020, and half of those surveyed caught COVID-19. The 26 people who didn’t get contract coronavirus, however, had higher levels of T-cells than those who did.
"We found that high levels of pre-existing T-cells, created by the body when infected with other human coronaviruses like the common cold, can protect against COVID-19 infection," Dr. Rhia Kundu, the author of the study, told Reuters.
While it has been cautioned that this is not to be considered a defense against COVID-19 alone, the study could offer new insights for vaccine manufacturers.
“These data should not be over-interpreted. It seems unlikely that everyone who has died or had a more serious infection, has never had a cold caused by a coronavirus," the University of Reading's Dr. Simon Clarke told the BBC. "And it could be a grave mistake to think that anyone who has recently had a cold is protected against Covid-19, as coronaviruses only account for 10-15% of cold."
Current vaccines, from the likes of Pfizer and Moderna, target spike proteins which mutate frequently. T-cells from the body, however, target the internal virus proteins. These don’t change as often as the spike proteins, and as such it’s possible new vaccines that utilize this approach could provide longer lasting protection against COVID-19.
“The internal proteins targeted by the protective T-cells we identified mutate much less," added study co-author Ajit Lalvani. "Consequently, they are highly conserved between the various SARS-CoV-2 variants, including Omicron. 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."
