T-Cells From Common Colds Could Help Create A ‘Variant-Proof’ Covid Vaccine 

According to new research from the Imperial College London, T-cells that are generated as part of the body’s natural immune response to the common cold could help protect against serious Covid-19 illness, and potentially lead to a vaccine that would be effective against new variants of the virus. 

The recently published study began back in September 2020 and followed 52 household contacts of people who had tested positive for Covid-19. The data showed that 26 people who were exposed to the virus, but didn’t show any symptoms, had significantly higher cross-reactive T-cells, which were generated by previous common colds.

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“The conclusion should not be that if you’ve had a common cold you don’t need to worry about contracting COVID-19. This is so for a number of reasons, including that not all colds are caused by coronaviruses, and T-cells’ ability to fight off symptomatic infections wanes over time,” Professor Aljit Lalvani, one of the authors of the study, explained. 

“What the study tells us is that there is a mechanism, a natural mechanism of natural protective immunity, that is triggered by previous common cold coronavirus infections, so we want to harness that naturally occurring protective immunity to develop better vaccines.”

Lalvani explained that the majority of the current Covid-19 vaccines out there specifically target the virus’ spike protein, as that’s the part that attacks healthy human cells. The vaccines then cause the body to produce antibodies and T-cells that can respond to that protein. 

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He then explained how the new research found that T-cells created after a common cold caused by other coronaviruses (which are common) can attack a type of protein that remains similar among all the known Covid-19 variants. These proteins are what give the virus the ability to replicate itself. 

“The fact that the T-cells can attack the internal proteins of each of these related COVID-19 variants means that they give what’s called a broad cross-protection. That’s in sharp contrast to the surface spike protein, which is the target of antibodies induced by vaccines.”

“Clearly, SARS-CoV-2 is under huge, intense pressure in the global population because most people now have these antibodies, whether induced by vaccination or infection, so the virus is trying naturally to evade that immunity through mutation, and that’s why Omicron has such a high number of mutations in the spike protein. But the internal proteins are relatively unchanged,” Lalvani stated. 

“We’re very fortunate to have found what immunologists refer to as the ‘Holy Grail,’ so we’re keen for people to understand this and to see that, at last, there is a path towards dealing with future variants.”

“This is now a definitive green light to move forward and develop a T-cell inducing vaccine to internal core proteins, which should protect against current and future variants,” he said.