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This paper is a year old and I am not an expert on anything, but I feel this article introduces something worth looking at in terms of understanding COVID damages that can't be linked to spike protein.

The Long-COVID Syndrome: Neoantigens as Driving Force for the Onset of Autoimmune Diseases - Rolf Marschalek

Rolf Marschalek has come up in the rececent McKernan et. al. oncology publication controversy.

Marschalek proposes eternal vaccination for COVID, and has his biases. But I feel that his theoretical paper below discusses a potentially worthy piece of the puzzle. Adding a massive number bad things to the virus does not detract from the massive number of bad things about the mRNA vaccines. Both are on the same side of the teeter-totter.

He seems to be trying to cast attention away from engineered Spike, but it was the first time I had read of the 2 nasty proteases in Covid-19 (and shared by MERS and other viruses).

It sounds like a nasty process, not unique to our favorite bat flu - and if it's going on in addition to the multifaceted spike injuries, it adds even more static to the signals. We can talk about autoimmunity from overproduced spike motifs and numerous frameshift off-targets, and contaminated shots, but he is talking about self proteins directly being added to the autoimmune attack from viral NSP5(3CLPro) and NSP3(PLPro).

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Copilot:

The Long-COVID Syndrome: Neoantigens as Driving Force for the Onset of Autoimmune Diseases - Rolf Marschalek

Summary of the Paper

The title "The Long-COVID Syndrome: Neoantigens as Driving Force for the Onset of Autoimmune Diseases" refers to a 2025 commentary article (often classified as an open-access commentary or hypothesis paper) authored by Rolf Marschalek, published in the Journal of Cellular Immunology (Volume 7, Issue 1, pages 26–31). scientificarchives.com

Central Hypothesis

Marschalek proposes that Long COVID (LC, also known as post-acute sequelae of SARS-CoV-2 infection) is primarily an autoimmune disorder triggered by the massive production of neoantigens during SARS-CoV-2 infection.

These neoantigens arise when the virus's two proteases—NSP3 (papain-like protease, PLPro, sometimes referred to as MPro in the paper) and NSP5 (3C-like protease, 3CLPro)—cleave not only viral proteins but also thousands of human host proteins in infected cells.

This cleavage generates novel peptide fragments (neoantigens) that the immune system misrecognizes as foreign, leading to autoreactive T-cell responses, production of functional autoantibodies (fAABs), chronic inflammation, and diverse autoimmune symptoms.

The author estimates this mechanism affects ~10% of all SARS-CoV-2-infected individuals worldwide, explaining the wide variability in LC symptoms (from organ-specific damage to systemic conditions like myalgic encephalomyelitis/chronic fatigue syndrome, ME/CFS).

Key Evidence and Data

Bioinformatics analysis of the human proteome (~72,000 proteins) shows SARS-CoV-2 proteases target approximately 6,500 human proteins (NSP3: ~602; NSP5: ~6,439; some overlap). This is based on consensus cleavage sites ("L-GG•A/K" and "LQ•A/S").

In contrast, common latent viruses target far fewer human proteins (e.g., EBV: 2; HSV6/7: 3; other Herpesviridae: 8–50; CMV: 68), making neoantigen-driven autoimmunity less likely in those infections (where molecular mimicry via "mimotopes" plays a larger role).

Other viruses/parasites (e.g., rhinoviruses: ~11,577 targets; flaviviruses/hepaciviruses: 7,198–20,516) cleave more but are adapted for persistence without overwhelming immune attack.

Post-infection studies (e.g., in hamsters and humans) show ~90% of antibodies target host proteins rather than viral ones.

Cleavage disrupts key pathways (e.g., IL-12/IL-35 signaling via JAK1/2, TYK2, STAT1/4), impairing interferon responses and viral clearance, contributing to persistence.

Proposed Mechanisms and Symptoms

Neoantigens are presented on MHC molecules → chronic CD8+/CD4+ T-cell activation → fAABs (especially against G-protein-coupled receptors, GPCRs) → symptoms like vascular damage, multi-organ failure, thrombosis, neurocognitive issues, hypertension, type II diabetes, dementia, and chronic fatigue.

Additional factors: Complement dysregulation, CD8+ T-cell loss, EBV reactivation, and interferon inhibition by viral proteins.

Conclusions and Implications

The pandemic is "not yet over" due to ongoing Omicron evolution (~4 new strains/year).

Prevention: Annual targeted vaccinations (mRNA or classical) reduce LC risk by ~45–50%; repeated infections increase it.

Treatment ideas: Protease inhibitors (e.g., Paxlovid targeting NSP5), aptamers like BC007 (to neutralize fAABs against GPCRs, in trials), or apheresis.

The hypothesis explains LC's heterogeneity and diagnostic challenges, as outcomes depend on individual MHC presentation of neoantigens.

This is a theoretical/commentary piece based on bioinformatics and existing literature, not new experimental data. The full open-access article is available online (e.g., via Scientific Archives or ResearchGate). Other reviews discuss related ideas like molecular mimicry or autoimmunity in Long COVID, but Marschalek's focus is uniquely on protease-generated neoantigens as the dominant driver.

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>>>>so what is the difference between protease-generated neoantigens and autoimmunity and mimicry?

Molecular Mimicry vs. Protease-Generated Neoantigens in Autoimmunity

Autoimmunity occurs when the immune system mistakenly attacks the body's own tissues. Both molecular mimicry and protease-generated neoantigens are proposed mechanisms that can trigger autoimmunity during or after viral infections, but they operate in fundamentally different ways.

1. Molecular Mimicry

This is the classic, long-established mechanism.

Viral proteins (or peptides derived from them) happen to share sequence or structural similarity with human host proteins.

The immune system generates antibodies or T-cells against the viral peptides.

These immune effectors cross-react with similar-looking human proteins because of the resemblance (called "mimotopes").

Result: Autoimmunity without any direct modification of host proteins.

Common in infections with latent viruses like Epstein-Barr Virus (EBV), Herpesviruses, or CMV, where only a handful of human proteins are subtly similar to viral ones.

The similarity is coincidental or evolutionary, and the host proteins remain intact and unchanged.

2. Protease-Generated Neoantigens (as proposed by Marschalek for SARS-CoV-2)

This is a more direct and aggressive mechanism unique to viruses with highly active proteases.

SARS-CoV-2 has two viral proteases (NSP3/PLpro and NSP5/3CLpro) that cleave viral polyproteins but also extensively cleave thousands of human host proteins at specific consensus sites.

This cleavage physically breaks human proteins into novel peptide fragments that did not exist before in the body.

These brand-new fragments ("neoantigens") are presented on MHC molecules to T-cells.

The immune system treats them as completely foreign (because they are truly novel sequences), mounting a strong response against them.

Since these neoantigens are derived from self-proteins, the response becomes autoreactive → autoantibodies and T-cell attack on intact host proteins or cells expressing them.

No sequence similarity to viral proteins is required—the damage is done by literally chopping up host proteins.

In Marschalek's hypothesis, SARS-CoV-2's unprecedented protease activity on host proteins makes neoantigen-driven autoimmunity the dominant mechanism for Long COVID, rather than mimicry (which plays a bigger role in other viral-triggered autoimmune diseases).

This explains why Long COVID affects ~10% of infections with such diverse symptoms—individual MHC presentation of different cleaved peptides leads to personalized autoimmune profiles. Mimicry alone couldn't generate enough "new" targets to account for the observed breadth.

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