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This is an old revision of this page, as edited by 82.69.83.28 (talk) at 23:42, 2 August 2021 (Rebuttal to another user). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Process diagram

In the 21:54, 17 August 2020 revision, @Olgamatveeva: replaced the diagram
with
Is the information in the former incorrect?

In general, it is better to update the vector graphics file, which is more easily editable, than to upload a raster version. If it is thought that the text labels in the latter are preferred to the former, I'll update the former and use it in the article.

Thanks,
cmɢʟee⎆τaʟκ 13:03, 3 February 2021 (UTC)[reply]

Hi cmɢʟee, Below is my list of issues with the previous illustration to help answer your question. Major points 1) “Denv” should be named as a “virus” or a “pathogen”. 2) ADE infection of immune cells is not always productive. For SARS-CoV and MERS-CoV the productive infection was not shown. Therefore, it should be mentioned that infectious or noninfectious virions are produced as a result of ADE. Minor points 1) FcyR was shown to be FcyRII (CD32) 2) B-cells were added to the list of immune cells that can be infected via ADE.I made a new figure.

File:Image for wiki ADE.tif
In antibody-dependent enhancement, sub-optimal antibodies (the blue Y-shaped structures in the graphic) bind to both viruses and Fc gamma receptors (labeled FcγRII) expressed on immune cells promoting infection of these cells

Olgamatveeva (talk) 15:18, 3 February 2021 (UTC)[reply]

Updated SVG
Thanks for the explanation, @Olgamatveeva: I've updated the vector diagram according to your TIF. Can you please let me know if other changes should be made in the future? Thanks, cmɢʟee⎆τaʟκ 03:09, 5 February 2021 (UTC)[reply]

Hi cmɢʟee, Great! I am glad that the illustration looks more professional now.I will let you know if any other changes have to be done in future. Sincrely, Olgamatveeva (talk) 12:43, 5 February 2021 (UTC)[reply]

@Olgamatveeva: @Cmglee: The new image may look cuter but it is factually incorrect: the antigen binds to either tip of the "Y", and not to the center of the "fork" as the picture suggests:
-- Wesha (talk) 09:52, 27 June 2021 (UTC)[reply]

Semi-protected edit request on 11 April 2021

Collapsed WP:MWOT

Alphacoronaviruses Edit The feline infectious peritonitis virus (FIPV) is an alphacoronavirus that is a very common pathogen in both domestic and wild cats.[7] It is believed that FIPV can cause antibody-dependent enhancement (ADE). Thus, vaccination against FIPV surprisingly increases the disease seriousness.[8] Moreover, it was demonstrated that infection of macrophages by FIPV in vitro can be triggered by non-neutralising monoclonal antibodies targeting the Spike (S)-protein, and this phenomenon can also occur with diluted neutralising antibodies.[9] ADE explains why half of cats develop peritonitis after being passively immunized with antivirus antibodies and being challenged with the same FIPV serotype. [10] In several countries an attenuated virus vaccine is available in a form of nasal drops; however, its application is still considered controversial by many experts, both in terms of safety and efficacy.[11] The mechanism of antibody-dependent enhancement for FIPV is illustrated in the video. [1]

Betacoronaviruses Edit

Antibody-dependent enhancement during coronavirus infection The neutralization ability of an antibody on a virion is dependent on concentration and the strength of interaction between antibody and antigen. High-affinity antibodies can cause virus neutralization by recognizing specific viral epitopes. However, pathogen-specific antibodies can promote a phenomenon known as antibody-dependent enhancement (ADE), which can be induced when the strength of antibody-antigen interaction is below the certain threshold.[12][13]

There are multiple examples of ADE triggered by betacoronaviruses.[12][13] Non-human primates vaccinated with modified vaccinia Ankara virus encoding full-length SARS-CoV spike glycoprotein and challenged with the SARS-CoV virus had lower viral loads but suffered from acute lung injury due to ADE.[14] ADE has been observed in both severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) animal models allowing the respective viruses to enter cells expressing Fc𝛾R including myeloid lineage cells.[15] It was shown that the SARS-CoV-1 virus (SARS-CoV) can enter macrophages via a antibody-mediated pathway and it can replicate in these cells. [16]


S-protein and N-protein models of SARS-CoV-2 virus. Both models are reproduced with modifications from the https://www.preprints.org/manuscript/202003.0138/v1n. [13] . It is likely that the amino acids variability of the S-protein represents a result of antigenic drift. ADE of acute lung injury has been documented in animal models of both SARS and MERS. Rabbits intranasally infected with MERS-CoV developed a pulmonary infection characterized by viremia and perivascular inflammation of the lung, and an antibody response that lacked neutralizing antibodies.[17] The rabbits developed more severe lung disease on re-exposure to MERS-CoV, and developed neutralizing antibodies after reinfection.[17] In SARS, mice vaccinated with four types of vaccines against SARS-CoV, as well as those infected with SARS-CoV itself, developed neutralizing antibodies.[18] Mice were then challenged with live SARS-CoV, upon which all developed immunopathologic-type lung disease, although none had detectable virus two days after challenge and were protected compared to control.[18] The development of immunopathology upon exposure has been a major challenge for coronavirus vaccine development[18] and may similarly impact SARS-CoV-2 vaccine research.

ADE in coronavirus infection can be caused by high mutation rate of the gene that encodes spike (S) protein. A thorough analysis of amino acid variability in SARS-CoV-2 virus proteins, that included the S-protein, revealed that least conservative amino acids are in most exposed fragments of S-protein including receptor binding domain (RBD). Therefore, antigenic drift is a most likely cause of amino-acids variability in this protein [13][19] and ADE. This drift can occur in a form of changes of both types of antigenic epitopes, including conformational and linear.

The pathophysiology of SARS and COVID-19 diseases may be associated with ADE. The authors of the study[13] believe that ADE is a key step in the progression of disease from its mild to severe form. Onset of ADE, due to antigenic drift, can explain the observed sudden immune dysregulation, including apoptosis of immune cells, which promotes the development of T-cell lymphopenia and an inflammatory cascade with the lung accumulation of macrophages and neutrophils, as well as a cytokine storm. ADE goes along with reduction of Th1 cytokines IL2, TNF-α and IFN-γ and increase of Th2 cytokines IL-10, IL-6, PGE-2 and INF-α, as well as with inhibition of STAT pathway.[20]

Perhaps ADE is the reason why the course of SARS and COVID-19 is more severe for older people compared to younger people. It is likely that in older people the production of antibodies is slower and by the time the antibodies are developed in the titer that is sufficient to neutralize the virus, the virus changes its antigenic determinants. In this case, immuno-dominant neutralizing antibodies might start forming unstable complexes with the new form of the virus and start to infect monocytes/macrophages causing ADE. This process can trigger generalized infection of immune cells in multiple organs and cytokine storm.[21][22]

It is interesting that in mice similar phenomenon of developing more severe disease in old compared to young animals exists. In contrast to old mice, in young mice, despite detectable viral replication оf SARS-CoV-1 in the lungs upon infection, clinical signs of the disease do not develop.[23]



You guys removed this part ...for... some... odd...reason.... while it was for the article for over a year at least.

Add it back up.

 Not done Unclear what, if any, request is being made. 04:58, 1 May 2021 (UTC)

Simple English needed

This article desperately needs a Simple English language version.74.194.157.22 (talk) 23:27, 17 June 2021 (UTC)[reply]

Why is this article linked in the Coronvirus section? Is there any compelling evidence that it's false or misinformation? Barely a few lines in the section compared to the others and link implying it's false information but not exactly proven as such. I've seen a number of top vaccinologists and microbiologists talk about this, and frankly they seem more credible than what the media are saying. † Encyclopædius 15:50, 16 July 2021 (UTC)[reply]

There's more information at the linked article. The issue seems to be antivaxxers saying this is a reason to avoid vaccination. Alexbrn (talk) 15:54, 16 July 2021 (UTC)[reply]
There's people who've worked for big Pharma and are still vaccine makers who've expressed a concern about this. It's not only antivaxxers claiming it. There's been a few who are otherwise credible scientists and have no reason to be claiming it, they don't have an anti vaxx agenda. † Encyclopædius 16:19, 16 July 2021 (UTC)[reply]
You need a credible source for "don't get vaccinated because ADE", because it sounds like antixvaxx BS. Alexbrn (talk) 16:25, 16 July 2021 (UTC)[reply]
And that's the issue. Youtube/Twitter/Facebook delete most videos of non anti vaxx scientists claiming this and "credible" mainstream sources won't cover it because there is an agenda to vaccinate everybody. No media outlet we consider a "reliable" source will allow this to be discussed fairly with two sides to an argument. † Encyclopædius 16:31, 16 July 2021 (UTC)[reply]
If if not deleted, Youtube/Twitter/Facebook would never carry a credible source for Wikipedia's purposes - rather that's where you'd find antixvaxx BS, which it seems you have signed up to. Alexbrn (talk) 16:34, 16 July 2021 (UTC)[reply]

Geert Vanden Bossche is a top vaccinologist and generally pro vaccine and has called for a debate on this and been turned away...Not your typical antivaxx types. Who made you the guardian of this article anyway?† Encyclopædius 16:36, 16 July 2021 (UTC)[reply]

I should think no good editor is going to think an antivaxx vet[1] is a reliable source. Alexbrn (talk) 16:45, 16 July 2021 (UTC)[reply]
That's because you define "Good Editor" as someone who agrees with you. What's your degree in? Literature? Publishing? 98.219.224.139 (talk) 19:58, 31 July 2021 (UTC)[reply]
Thats not enough to proclaim Bossche as an "anti-vaxx vet", thats just serious cherrypicking. Bossche is generally pro-vaccine, and is a damn sight more credible than you, Alexbrn. Quit it with your holier-than-thou attitude, and actually engage with the argument being made.
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