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.Read the latest updates in our dedicated coronavirus section. Immunity against COVID-19 is a complex picture, and while there is evidence of waning antibody levels six months after vaccination, T-cells 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.Current COVID-19 vaccines target the spike protein, which mutates regularly, creating variants such as omicron which lessen the efficacy of vaccines against symptomatic infection.“In contrast, the internal proteins targeted by the protective T-cells we identified mutate much less,” Professor Ajit Lalvani, co-author of the study, said.“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.”Read more: Cyprus scientists discover new ‘deltacron’ COVID-19 strainBritain seeks help from private health firms as omicron wave loomsOverwhelmed by omicron surge, US hospitals delay elective surgeries
Source: Al Arabiya
Full Article: T-cells from common colds can provide protection against COVID-19: Study
