Sub-Journal of "Science": For the first time, we have found evidence of long-term immune memory of COVID-19 in the human body!

"The new crown, you must suppress it at any time! If you don't suppress it, you can't do it.
Think about it.
You can't cook, you are renting a house by yourself.
It is about to go home for the New Year.
It is sealed, the whole city is sealed.
.
.
So, the days without the new crown are good days! "Suppression, to suppress, not to suppress it will not work.
At the beginning of 2020, the new crown began to sweep the world
.

And just four days after the start of this year, as a singularity cake living in Shijiazhuang, he finally experienced it
.

No matter what the mood is, I believe that many people now have various unforgettable experiences due to the epidemic
.

A week ago, the two colleagues of Qidian Cake were told that they could only work at home in the Feng community.
Some colleagues felt sorry (mu) for this
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We can hardly forget the experience of the epidemic, and our immune system will also leave a deep memory of the invasion of the new coronavirus
.

Recently, led by Professor Donna Farber of Columbia University and Professor Shane Crotty of the La Jolla Institute of Immunology, they found direct evidence that the new crown infection has a long-term immune memory
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They found that there are not only SARS-CoV-2 specific memory T cells and memory B cells, but also SARS-CoV-2 specific germinal centers in the lungs and lymph nodes around the lungs of patients with new coronary disease [1]
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This has important guiding significance for the design of vaccination or optimized immunity
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The article was published in Science Immunology, a subsidiary of Science
.

Screenshot of the paper's homepage Although many studies have found one after another that patients with new crowns do still have specific immunity after months or even a year of recovery
.

However, the samples in these studies are all peripheral blood without exception [2-9], and there is no relevant research to find memory cells from organ tissues
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In fact, the adaptive immune response also performs a protective function in organs and tissues
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Those memory T cells that exist only in organs and tissues, but not in the circulatory system and blood are called tissue-resident memory T cells (Trm)
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Tissue-resident memory T cells are very important for the body's immune protection and resistance to viral infections.
They can recognize antigens in time, directly send out the police in situ, and call the immune system for reinforcements [10-12]
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 Therefore, researchers hope to find these memory cells in the organs and tissues of patients with new coronary disease
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Fortunately, the researchers managed to find the organ samples of 4 patients (10-74 years old) who recovered after being infected with the new crown
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The cause of death of these patients has nothing to do with the new crown, and organ donations were performed after death, and the SARS-CoV-2 PCR was negative
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On the other hand, the researchers also selected some organ donors who were not infected with the new crown as controls
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After a series of studies by four organ donors who have recovered from the new crown, they found that even after 6 months of infection with the new crown, SARS-CoV-2 specific memory T cells and memory B cells still exist in the patient’s bone marrow, spleen, lung, and multiple lymph nodes , And the lungs and lung-related lymphoid tissues are the most important parts of the distribution of these memory cells
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Among them, in these organs and tissues and blood of COVID-19 rehabilitation patients, CD4+ memory T cells are generally more abundant than CD8+ memory T cells, but the level of CD8+ memory T cells varies greatly among individuals
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The memory T cell subsets in blood and different tissues are also different
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In the lungs and lung-related lymphoid tissues, the SARS-CoV-2 specific memory B cells that account for the largest proportion are of the IgG+ type
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In other tissues and blood, there are also IgG+, IgM+, and IgA+ type memory B cells
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The abundance of memory CD4+ T cells and memory CD8+ T cells of all epitopes in blood and different tissues is not only that, the researchers also found more direct evidence to prove that the new coronavirus infection has left a deep impression on the immune system Memory
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They found SARS-CoV-2 specific germinal centers and follicular helper T cells (TFH) in the lungs and lung-related lymphoid tissues of patients with new coronary disease
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After virus infection or antigen immunization, a microstructure-the germinal center is formed in the secondary lymphatic organs (such as the spleen and lymph nodes)
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B cells can achieve clonal proliferation here, and with the assistance of TFH, produce memory B cells and plasma cells with longer lifespan and higher affinity [13]
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In other words, after being infected by the new coronavirus, the lungs and lung-related lymphatic systems have established a B-cell task force specifically for the new coronavirus to establish a long-term immune memory to combat re-infection in a more timely and efficient manner
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There are germinal centers found in the lungs and lung-related lymphatic system.
In general, these findings of the researchers are sufficient to prove that after the new crown patient is infected with the virus, it is not only in the blood, but also in the bone marrow, spleen, lung and multiple lymph nodes.
These local tissues can also produce immune memory
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The "most memorable" tissue is the lungs and the related lymphatic system of the lungs
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 It is worth noting that among the four organ donors, two of the patients recovered from the new crown are over 70 years old
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We usually think that the immune system enters a standby state in old age and basically depends on the existing memory cells to protect itself
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However, this study found that after the two elderly people were infected with the new coronavirus, germinal centers also appeared in the lungs and related lymphatic systems of the lungs
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The researchers said: "Elderly people in their 70s can still produce significant and lasting immune memory, which shows that when we get old, some of the immune systems that are considered to be age-related are actually still functioning
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" In addition, the researchers At present, research is also carried out on organ donors who have been vaccinated to determine whether the immune memory caused by the vaccine is similar to the immune memory caused by natural infection
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They said that if vaccines can be designed more specifically in the future, such as nasal spray vaccines, to help lungs and lung-related tissues establish specific germinal centers before the real new coronavirus invades, it may improve the effectiveness of vaccines
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Finally, Singularity Cake would like to thank the medical staff and volunteers who stood by their posts when the epidemic came! Everyone still has to take personal protection.
When the epidemic is over this winter, before the Winter Olympics, Zhangjiakou Snow Resort will make an appointment~ References: [1] Poon MML, Rybkina K, et al.
SARS-CoV-2 infection generates tissue-localized immunological memory in humans.
Sci Immunol.
2021 Oct 7:eabl9105.
[2]JM Dan, J.
Mateus, et al.
Immunological memory to SARS-CoV-2 assessed for up to 8 months after infection.
Science 371, ••• (2021).
[3]A.
Grifoni, D.
Weiskopf, et al.
Targets of T Cell Responses to SARS-CoV-2 Coronavirus in Humans with COVID-19 Disease and Unexposed Individuals.
Cell 181, 1489 –1501.
e15 (2020).
[4]C.
Gaebler, Z.
Wang, et al.
Evolution of antibody immunity to SARS-CoV-2.
Nature 591, 639–644 (2021).
[5]Z.
Wang, F.
Muecksch, et al.
Naturally enhanced neutralizing breadth against SARS-CoV-2 one year after infection.
Nature 595, 426–431 (2021).
[6]LB Rodda, J.
Netland,et al.