Top journals have published articles: This vaccine can protect the new crown variant with just one shot?

▎Editor of WuXi AppTec's content team Today, a paper published in "Nature" introduced the latest development of a new crown vaccine
.

Studies have found that this vaccine produces more than one protective mechanism: even if part of the protective power is reduced before the new coronavirus is mutated, the remaining protective power can still play its own role! More importantly, this vaccine has been verified in the real world
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With just one shot, it can protect multiple COVID-19 variants
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This vaccine was developed by Johnson & Johnson and was authorized by the US FDA for emergency use a few months ago
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In order to better understand the immunogenicity of this vaccine, the researchers vaccinated 20 volunteers
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Subsequently, they analyzed the protective power of the vaccine in volunteers from multiple dimensions
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The first is the level of neutralizing antibodies produced by the vaccine
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Scientists found that compared with the new coronavirus in the early stage of the epidemic (without mutation), the neutralizing antibody titers produced by the vaccine decreased in the face of beta variants (originally discovered in South Africa) and gamma variants (originally discovered in Brazil) , The decline was 5.
0 and 3.
3 times respectively
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This finding is also consistent with previous studies that the mutant virus can have a negative impact on the protection of neutralizing antibodies
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But in addition to neutralizing antibodies, non-neutralizing antibody reactions and T cell reactions are almost unaffected by mutant viruses
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The researchers pointed out that even in the face of beta variant viruses, antibody-dependent cellular phagocytosis, complement deposition, and activation of NK cells in volunteers are mostly well preserved
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In addition, whether it is a new coronavirus that has not mutated, or an alpha variant (originally discovered in the UK), a beta variant, and a gamma variant, the CD8 and CD4 T cell responses in the volunteers are all at the same level
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This also shows that in addition to neutralizing antibodies, the T cell response in the human body may hold the bottom line of anti-virus
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Some people may ask, are these results worth referring to? In the real world, can immune responses other than neutralizing antibodies also provide adequate protection for vaccinators? A paper in the New England Journal of Medicine earlier this year answered this question
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In a phase 3 clinical trial, nearly 20,000 people received a single dose of the vaccine, and another 20,000 people received a placebo
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It was found that the vaccine group outperformed the placebo control group
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Among the vaccinated groups, there are fewer moderate to severe-critical cases of new coronary disease, hospitalized cases, and deaths
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In terms of safety, vaccinators more often experience pain at the location of the vaccine, as well as symptoms such as headache, fatigue, myalgia, and nausea
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Most of the symptoms are mild to moderate and only last for 1-2 days
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The conclusion of the paper pointed out that Johnson & Johnson's single-dose vaccine has shown safety and effectiveness in combating symptomatic new coronary diseases
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▲The mechanism of action of this vaccine (picture source: reference [2]) A press release from Harvard University today mentioned that based on the protective effect in the Phase 3 clinical trial, the non-neutralizing antibodies shown in the "Nature" paper The response and T cell response may play a protective role against new coronary diseases
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Considering that this Phase 3 clinical trial has recruited many volunteers in South Africa and Brazil and other places, the significance of this finding is particularly important
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"The current vaccine is designed for the original strain of the new coronavirus at the beginning of the epidemic
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Whether the new coronavirus variant will reduce the effectiveness of these vaccines is a matter of concern," said Dan H.
Barouch, a professor at Harvard Medical School and the corresponding author of the "Nature" paper.
Said, “Although the mechanism for the protection of the new crown is not clear, the strong protective effect of this vaccine in these areas increases the possibility that the non-neutralizing antibody response and/or T cell response may bring protection.

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another possibility is that even very low levels of neutralizing antibodies, is enough to produce a protective force for the new crown
.
"Taken
together, these studies found that the new vaccine crown can bring a variety of potential protection mechanisms, and some vaccines only It takes one shot to produce better protection
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For the protective effect of the vaccine, these two papers also brought deeper insights
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Considering that the new coronavirus has not been completely eradicated, getting a vaccine as soon as possible may be a good way to protect yourself
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Reference: [1] Alter, G.
, Yu, J.
, Liu, J.
et al.
Immunogenicity of Ad26.
COV2.
S vaccine against SARS-CoV-2 variants in humans.
Nature (2021).
https:// doi.
org/10.
1038/s41586-021-03681-2[2] Jerald Sadoff et al.
, (2021), Safety and Efficacy of Single-Dose Ad26.
COV2.
S Vaccine against Covid-19, NEJM, DOI: 10.
1056/ NEJMoa2101544[3] Single-shot COVID-19 vaccine generates robust immune responses against variants, Retrieved June 9, 2021, from https://news.
harvard.
edu/gazette/story/2021/06/single-shot-covid-19 -vaccine-effective-against-variants/