[ad_1]
People who have recovered from COVID-19 retain broad and effective long-term immunity to the disease, according to a new study.
The results of the study, which is the most comprehensive of its kind to date, have implications for expanding the understanding of human immune memory as well as the future development of coronavirus vaccines.
For the longitudinal study in Cell Reports Medicine, researchers looked at 254 patients with mostly mild to moderate symptoms of SARS-CoV-2 infection over a period of more than eight months (250 days) and found that their immune response to the virus remained sustainable. and strong.
The results are reassuring, especially given early reports during the pandemic that protective neutralizing antibodies did not last in COVID-19 patients, said Rafi Ahmed, director of the Emory University Vaccine Center and lead author of the article.
“The study serves as a framework to define and predict long-term immunity to SARS-CoV-2 after natural infection. We also saw indications in this phase that natural immunity may continue to persist, ”Ahmed said.
The research team will continue to assess this cohort over the coming years.
The researchers found that not only did the immune response increase with the severity of the disease, but also with each decade of age, regardless of the severity of the disease, suggesting that there are other unknown factors influencing the disease. age-related differences in COVID-19 responses.
By following patients for months, researchers got a more nuanced view of how the immune system responds to COVID-19 infection. The resulting image indicates that the body’s defense shield not only produces a range of neutralizing antibodies, but activates certain T and B cells to build immune memory, providing stronger defenses against reinfection.
“We saw that antibody responses, especially IgG antibodies, were not only long-lasting in the vast majority of patients, but degraded at a slower rate than expected, suggesting that patients generate plasma cells for longer. lifespans that can neutralize SARS-CoV- 2 protein spikes.
Ahmed said investigators were surprised to see recovering participants also exhibited increased immunity to common human coronaviruses as well as SARS-CoV-1, a close relative of the current coronavirus. The study suggests that patients who survived COVID-19 are likely to also possess protective immunity even against certain variants of SARS-CoV-2.
“Vaccines that target other parts of the virus rather than just the spike protein may be more useful in containing the infection, as the SARS-CoV-2 variants outgrow the dominant strains,” Ahmed said. “This could pave the way for us to design vaccines that treat multiple coronaviruses. “
The researchers said the study more fully identifies adaptive immune components leading to recovery and will serve as a benchmark for immune memory induced by SARS-CoV-2 vaccines.
“We can build on these results to define progression towards long-lasting immunity to the novel coronavirus, which can guide rational responses when future outbreaks occur,” Ahmed said.
The National Institutes of Health funded the work, which is a collaboration between Emory University and the Fred Hutchinson Cancer Research Center in Seattle, Washington.
This article was originally published by Rajee Suri. Republished via Futurity.org under Creative Commons License 4.0.
[ad_2]
Source link