The lungs have a strong "immune memory" for the new crown infection, new research suggests that the vaccine response may exceed expectations

▎Editor of WuXi AppTec's content team After the human body encounters the new coronavirus, the immune system will not only fight the virus, but also "remember" them for a long time to prevent re-infection
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This long-term immune memory is also the basis for the vaccine's protective effect
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In a new study, scientists found direct evidence of long-term immune memory of new coronary infections in the lungs of patients with new coronary disease and the lymph nodes around the lungs
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Confirming the immune memory of the new crown infection has important guiding significance for the design of vaccination or booster immunity
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▲The research was published in Science Immunology, a subsidiary of Science.
This research was led by Columbia University (Columbia University) immunologist Professor Donna Farber and La Jolla Institute of Immunology virologist Professor Shane Crotty
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Four patients who recovered after being infected with the new crown in 2020 provided valuable samples for researchers
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These patients died for other reasons unrelated to the new crown and donated organs after their deaths
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Researchers quickly performed isolation and functional analysis of immune cells in organ tissues, and compared them with organ donors who have not been infected with the new crown
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▲The new coronavirus-specific immune cells were detected in the tissues of four organ donors who had previously been infected with the new crown (picture source: reference [1]).
The results of the study showed that until six months after the infection of the new crown, the patient’s bone marrow There are still a large number of memory CD4 positive T cells, CD8 positive T cells and B cells in the spleen, lung and multiple lymph nodes
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Among them, lung and lung-associated lymphoid tissues are the most important part of the distribution of SARS-CoV-2 specific memory B cells and memory T cells
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In lung-related lymph nodes, the researchers also found that SARS-CoV-2 specific germinal center B cells and follicular helper T cells (Tfh) coexist, the latter can promote the differentiation of B cells, and the germinal center B cells Persistence can ensure the long-term maintenance of antibodies in the circulatory system and the persistence of the immune response
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This series of findings provide direct evidence that local tissues have established long-term protective immunity after the new crown infection
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Image source: 123RF It is worth noting that among the four new crown patients examined by the researchers, some are over 70 years old
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In other words, even the elderly can build a strong immune memory against a pathogen that has never been exposed to
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"We know that the immune system weakens with age, but since people in their 70s can produce a significant and long-lasting immune memory response, it shows that the part of the immune system that we usually think is linked to youth is still working
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" Professor Farber explained
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To extend it further, this discovery means that the immune response generated by the vaccine in the elderly may also be stronger than previously thought
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▲The two corresponding authors of the study, Professor Donna Farber and Professor Shane Crotty (picture source: the official website of the researcher's institution) In addition, the type and location of immune memory generated after infection has also brought new inspiration for vaccine design
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"Our research shows that in order to strengthen the resistance to the virus, the vaccine should target the memory immune cells in the lungs and related lymph nodes, and the nasal spray vaccine can achieve this
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"Professor Farber believes, "In the past, we found in mice infected with influenza that the lungs need memory T cells to best prevent respiratory infections.
This study strongly proves that the same is true for humans
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"Researchers are still continuing to study vaccinated organ donors to determine whether the immune memory caused by the vaccine is similar to the immune memory caused by natural infection
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This research may deepen our understanding of the immune system, in order to fight against new coronary pneumonia.
Provide new ideas
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Reference materials: [1] Maya ML Poon et al.
, (2021) SARS-CoV-2 infection generates tissue-localized immunological memory in humans.
Science Doi: 10.
1126/sciimmunol.
abl9105 [2] Lung maintains long- term memory of COVID infection.
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