Examine exhibits promising immune response in opposition to variants

Scientists at the Mirimus Laboratory prepare to test COVID-19 samples from recovered patients on April 8, 2020 in Brooklyn, New York.

Mischa Friedman | Getty Images

One type of T cell responsible for destroying cells infected with viruses was able to detect three variants of Covid-19 in a small US study, a promising sign that vaccines should continue to protect against new, emerging strains researchers at the National Institute of Allergy and Infectious Diseases said Tuesday.

Researchers led by NIAID researcher Andrew Redd investigated whether T cells were found in blood samples from patients recovering from the original strain of virus that recognized B.1.1.7, the variant B.1.351 originally detected in the UK was originally found in South Africa and P.1, first seen in Brazil. The NIAID is part of the National Institutes of Health, which published the study.

Each of the three variants the scientists examined contained mutations in what is known as the spike protein, which the virus uses to enter human cells. Mutations in this spike protein region could make it less noticeable to T cells and neutralizing antibodies, another important part of the immune response, after infection or vaccination, the researchers said.

In the study, which used blood samples from 30 recovered Covid-19 patients, T-cell responses “remained largely intact and were able to detect virtually all mutations in the variants studied,” they said, adding that even larger studies are required.

“The researchers note that their results suggest that the T-cell response in convalescents, and most likely in vaccines, is largely unaffected by the mutations found in these three variants and should provide protection against emerging variants,” the US wrote Authority a press release.

The results of the study could give hope to public health officials as they attempt to vaccinate the US and other parts of the world. New variants have been a problem for health officials as studies have shown they can reduce the effectiveness of current vaccines. The Chief Medical Officer of the White House, Dr. Anthony Fauci, urged Americans to get vaccinated as soon as possible before potentially more dangerous variants emerge.

On Monday, the head of the Centers for Disease Control and Prevention, Dr. Rochelle Walensky, the reporter. She said she was concerned the nation was facing “impending doom” as variants spread and daily Covid-19 cases rise again, threatening to send more people to the hospital.

To be sure, scientists say strong responses from both antibodies and T cells are likely required to produce an effective immune response against the virus. Further studies to examine immune responses are still needed, the researchers stressed, including whether a booster shot would be effective against emerging variants.

“New variants continue to be identified around the world and it will be important to continuously monitor them for possible accumulation of T cell escape mutations,” the researchers wrote.

The researchers also noted that the study had limitations, including the relatively small size of the population studied, and that all participants were from North America.