HDo you currently have multiple protections against COVID-19? The answer depends on a lot: whether you had COVID-19 (and if so, how long ago); even you been vaccinated (and if so, how many times, and how recently); whether you have any medical conditions that can weaken your immune system; and such. Even antibody test there is only approximate immunity to COVID-19, so there is no simple way to know.
But an international team of researchers recently developed another tool to help assess COVID-19 immunity: a blood test that can measure T cells, the white blood cells that work together with the immune system. antibodies against the virus to induce an immune response. Their work is described in a new study published year Nature of Biotechnology.
T-cell testing for the SARS-CoV-2 virus is nothing new — US Food and Drug Administration licensed for emergency use Study co-author Ernesto Guccione, professor of cancer science at the Tisch Cancer Institute at Mount Sinai, said it tends to be laborious and time-consuming. . His team, which includes other researchers from Mount Sinai and institutions including Singapore’s Duke-NUS Medical School, aims to simplify it using widely accessible and accessible technology change results in less than 24 hours.
Their process begins with mixing a person’s blood sample with material from the SARS-CoV-2 virus. If there are SARS-CoV-2-specific T cells in the blood, they react with the viral material and produce a substance that can be detected through polymerase chain reaction (PCR) technology, like used to run diagnostic COVID-19 tests. The measured levels of that compound serve as a proxy for cellular immunity.
The test has been licensed to UK-based biotech company Hyris and is already in use in Europe. The FDA is still reviewing the technology, so it’s not yet available in the US (Hyris employees were co-authors of Natural Biotechnology paper, and its technology was used in the research; Guccione advises therapy companies and receives compensation through a licensing agreement between Hyris and Mount Sinai.)
Why test for T cells when antibody tests are widely available? Guccione says there are several reasons.
Testing for antibodies only tells part of the story, as T cells are also an important part of the body’s immune response. And while antibody levels drop significantly within months of vaccination or infection, cellular immunity can last up to a year, Guccione says. “Monitoring both will give us a much clearer picture [of immunity] and hopefully inform our revaccination strategies,” said Guccione. Widespread use of this test can help determine how long protection lasts and Regular dose booster is needed.
Plus, some immunocompromised people don’t make antibodies – even after multiple doses of the vaccine – but they often have some T-cell response. T-cell testing can help those people know. see if they have any defenses against COVID-19.
There are limits to what the test can reveal. Experts are still trying to find what are known as “correlations of protection” for COVID-19: measurable indicators that an individual is protected enough that they are unlikely to be able to afford it. possibility of illness. Currently, testing for antibodies or T . cells Can’t give you a yes or no answer such as whether it is safe to go to a concert or party without fear of catching the virus. It just gives you one more data point to calculate your risk.
Guccione says that extensive T-cell testing could help identify elusive correlations of protection by making it easier to study immunity. An affordable, scalable testing strategy could facilitate larger studies that yield much-needed answers.
“With big numbers comes clarity,” says Guccione. “That’s the hope: using this test, we can finally get numbers that previous technology didn’t have at all.”
Correction, June 13
The original version of this story misrepresented the financial relationship between Hyris and Guccione. He does not receive royalties directly from Hyris.
Other must-read stories from TIME