The team is currently studying whether COVID-19 vaccines also induce long-lived antibody-producing cells
Even a mild case of coronavirus could leave people with lifelong protection against the virus, a new study suggests, with researchers calling previous reports that immunity was not long-lived following infection “a misinterpretation of the data.”
In the study, conducted by Washington University School of Medicine in St. Louis and published May 24 in the journal Nature, researchers took bone marrow samples from 18 out of 77 participants who were already signed up to give blood samples at three-month intervals starting about a month after initial infection. The bone marrow samples were taken between seven and eight months after initial COVID infection. Five of the 18 participants then gave second bone marrow samples four months later.
The team compared those samples with bone marrow taken from 11 people who had never been diagnosed with COVID-19.
While antibody levels in the blood of people who had previous infections did drop quickly in the first few months before mostly leveling off, some antibodies were detectable even 11 months after infection. Researchers also found antibody-producing cells specifically targeting SARS-CoV-2, the virus that causes COVID-19, in 15 of the bone marrow samples. The cells were also found in all five of the follow-up samples given four months later.
The researchers said the cells are “quiescent, just sitting in the bone marrow and secreting antibodies.”
