Home » Immune imprinting, from Covid to other viruses: this is what it is

Immune imprinting, from Covid to other viruses: this is what it is

by admin
Immune imprinting, from Covid to other viruses: this is what it is

The first time is never forgotten. Or at least this is the case with our immune systems when it encounters a virus. From this first meeting, what scientists call “immune imprinting” is triggered: at the first exposure to the virus, either through infection or vaccination, the immune system imprints the invader in its memory in order to possibly recognize it in the future, thus conferring a certain level of protection.

Imprinting and anti-Covid vaccine

Now the immune imprinting would be at the center of the research of the new anti-Covid vaccine, the one “updated” based on the mutations accumulated by the Sars-CoV-2 virus in the last two years. Immunologists are in fact convinced that, since the pandemic broke out, people have acquired different immune imprints, depending on the strain or combination of strains to which they were exposed.

Covid vaccine, we distance calls to avoid ‘immune paralysis’

by Antonio Cassone


This, according to scholars, could lead to large differences in the immune response that each of us has against the virus responsible for Covid-19. This means that those who made the anti-Covid vaccine, developed on the original virus, the Wuhan variant, have an immune imprinting that only partially allows them to respond to a very different variant, such as the latter Omicron. “This is how we explain the decrease in protection recorded on the vaccination front: if with the Wuhan variant and the Delta variant the protection from infection was equal to 95%, with the Omicron variant we dropped to 50%”, he explains Sergio Abrignani, full professor of general pathology at the University of Milan, former member of the technical-scientific committee. “It means that thanks to the imprinting it had the first time with the virus, the immune system – he continues – recognizes only some of the amino acids present in the receptors that the virus uses to enter the cell. A partial recognition, therefore, that if it does not protect against contagion it certainly offers a good level of protection from serious illness. “

See also  Covid vaccine for children between 5 and 11 years, The Bioethics Committee: "We need a campaign in schools"

The real weapon against Omicron? T cells

by Daniele Banfi



However, Danny Altmann of Imperial College London, a scientist who is studying the phenomenon of immune imprinting with the Sars-CoV-2 virus, wonders: whether it is true that the first encounter with the virus, through infection or vaccination, shapes the next immunity through immune imprinting, is it possible that this could cause a “bad” response to new versions of the virus? In other words, can what was once called “original antigenic sin”, that is, immune imprinting, adversely affect the response to variants of the Sars-CoV-2 virus that are very different from the version of the virus that first encountered it?

Natural or artificial immunity? A question that makes little sense: here’s why

by Aureliano Stingi



The doubt arises from a study conducted by a team of researchers from Imperial College London on 700 healthcare professionals in the United Kingdom. The findings, published last month in the journal Sciencesuggest that Omicron infection had little or no beneficial effect in boosting any part of the immune system – antibodies, B cells, or T cells – among people who had been immune imprinted with previous Sars-Cov-2 variants.

Omicron is not benign but skilled and stealthy

“Omicron is anything but a benign natural vaccine immunity enhancer, as we might have thought, but it is a particularly stealthy immune evader,” Altmann said. With this hypothesis, the NoVax went to a wedding. According to their (il) logic, the immune imprinting following vaccination could compromise the response to the new variants of the virus. Hypothesis, this immediately dismissed by immunologists.

See also  Melanoma, early stage immunotherapy also works in the real world

Thanks to imprinting today few deaths

“This is absolutely not the case”, Abrignani underlines. “It is thanks to the immune imprinting resulting from vaccination if today, in the face of such a large wave of infections, we continue to register few serious cases and deaths. Indeed, among the unvaccinated – he continues – serious cases are much more frequent than among the unvaccinated “. Immune imprinting, in fact, does not prevent our immune system from refining its knowledge about the virus and its variants.

Vaccines updated to Omicron as a booster

The World Health Organization last month said that the updated vaccines on Omicron can be useful as a booster because it would expand protection against several variants. Booster, therefore not an alternative. The US Food and Drug Administration Advisory Committee instead expressed a favorable opinion on incorporating the genetic material of Omicron into the new booster vaccines. “We are trying to use every last ounce of what we can from predictive modeling and emerging data to try to anticipate a virus that has been very clever,” said Peter Marks, director of the FDA’s Center for Evaluation. and biological research.

The challenge of vaccines is to broaden the response

Moderna and BioNTech / Pfizer, the leading manufacturers of mRNA vaccines, have presented laboratory data showing that their latest versions, targeted at Omicron, produce a potent antibody response against the BA.4 and BA.5 variants. “Now the challenge of future Covid vaccines is to broaden the immune response against current and future variants as much as possible,” says Abrignani. “And we can do this only because behind us we have a large part of the world population immunized with the vaccines currently available”, she concludes.

See also  From vitamin D to melatonin: here are our allies against Covid-19

You may also like

Leave a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.

This website uses cookies to improve your experience. We'll assume you're ok with this, but you can opt-out if you wish. Accept Read More

Privacy & Cookies Policy