Nature: How does the new crown affect the immune system? Scientists found that the T cell activity profile of new crown survivors was elevated, and male recovered people had a stronger immune response to influenza vaccines

In the recent editorial office, gossiping topics are not only new crown or new crown, such as exchanging infection experience, Amway new crown papers, and outrageous rumor sharing.
.
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A colleague mentioned that there is still a saying
that "infected with the new crown 5 times, the immunization is directly finished" in his hometown.

There is no doubt that disease is a big test of the immune system, so after this test, is the immune system "completely flattened by the blow", or "come to fight one by one"?

This week, Nature published a new paper from the National Institutes of Health discussing changes
in the immune system after recovery.
The results of the study found that the activity characteristics of T cells in the recovered patients were all increased, but the expression of genes related to innate immunity in monocytes was reduced
.
Interestingly, there is a gender difference in the effect of influenza vaccination in people who have recovered from the new crown, and male recovered people can produce a better immune response
.

Thesis title map

The immune system has a "memory", for example, vaccination can improve our resistance to specific diseases, and some pathogens may also destroy the immune system, such as natural infection with measles, humoral immunity will be significantly impaired, and in the following months and years, will be more susceptible to other infectious diseases
.

At a time when everyone may have to "yang" once, we are naturally also concerned about what kind of impact
infection with the new crown will bring to the immune system.

The study I want to talk about today tries to compare the immunity of people who have recovered from the new crown and those who are not infected at the molecular level, and compare their reactions
after receiving the flu vaccine.

The recovered people in the study were infected during the first wave of the pandemic in 2020 and included a total of 31 mild patients and 2 asymptomatic infections, who were younger than 65 years old, who had symptoms lasting an average of 16.
5 days and an average of 151 days
had passed since diagnosis by the time of enrollment.
These people are still in relatively good health, with mild symptoms, no hospitalization, and no comorbidities
.

Research methods

The researchers then performed a series of analyses, including whole blood transcriptome analysis, CITE-seq, serum protein analysis, antibody characterization, major immune cell subsets, and lineage characterization, among others
.

Some immune parameters gradually subside with the time of recovery from the new crown, such as the new crown virus neutralizing antibody titers, but this is not the main concern of the research, what we want to know is the change
of long-term, stable immune status.

Overall, monocyte gene expression was suppressed in the recovered people, and T cells became more active
.

Interestingly, this change showed a clear sex difference, with male recovered patients having a significantly higher proportion of myeloid cells such as monocytes and conventional/myeloid dendritic cells than female convalescent cells and healthy controls, while the activation of CD8+ central memory T cells and effector memory T cells was also more pronounced
.

The researchers also analyzed two other sets of data on influenza A (mainly H1N1) and found similar phenomena, suggesting that infection with respiratory viruses can have long-lasting effects on immunity, although specific changes may be related to
the type of virus.

There are significant gender differences in the impact of coronavirus infection on immunity

The researchers then analyzed and compared the immune responses
of these participants after receiving the flu vaccine.
Why the flu vaccine? On the one hand, the research coincides with the flu season, and on the other hand, the immune changes after influenza vaccination have been clearly studied and can be easily compared
.

After receiving the influenza vaccine, male recovered patients showed a stronger innate and adaptive immune response and higher
circulating IFNγ levels.

Further analysis found that this relied on a special group of T cells, GPR56+CD8+ effector T cells, which exhibited a "bystander activation" response that could be activated only by inflammatory cytokines to produce IFNγ
without T cell receptor stimulation.

Happily, the researchers found that after receiving the flu vaccine, the mononuclear cells that were originally suppressed have gradually recovered to the level of healthy controls
.

Classical/non-classical monocytes