High levels of T-cells from common cold coronaviruses can provide protection against COVID-19, an Imperial College London study published on Monday has found, which could inform approaches for second-generation vaccines.
Immunity against COVID-19 is a complex picture, and while there is evidence of waning antibody levels six months after vaccination, They are also believed to play a vital role in providing protection.
The study, which began in September 2020, looked at levels of cross-reactive T-cells generated by previous common colds in 52 household contacts of positive COVID-19 cases shortly after exposure, to see if they went on to develop infection.
It found that the 26 who did not develop infection had significantly higher levels of those T-cells than people who did get infected. Imperial did not say how long protection from the T-cells would last.
“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,” study author Dr Rhia Kundu said.
The authors of the study, published in Nature Communications, said that the internal proteins of the SARS-CoV-2 virus which are targeted by the T-cells could offer an alternative target for vaccine makers.