This paper gives some more credibility to the idea that it's the components of the NLP sheath that are causing heart inflammation. Although the paper openly endorses the safety and effectiveness of the vaccines, it does point out some interesting things.
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Potential implications of lipid nanoparticles in the pathogenesis of myocarditis associated with the use of mRNA vaccines against SARS-CoV-2
Although mRNA-based vaccines BNT162b2 and mRNA-1273 exhibit a remarkable efficacy and effectiveness in preventing particularly severe Covid-19 with an…
www.sciencedirect.com
Quotes:
Potential implications of lipid nanoparticles in the pathogenesis of myocarditis associated with the use of mRNA vaccines against SARS-CoV-2
DimitriosTsilingiris, Natalia G.Vallianou, Irene Karampela, Junli Liu, MariaDalamag
published on Elsevier
The pathogenesis of mRNA-vaccine associated myocarditis has not yet been elucidated, although a number of mechanisms have been proposed, typically implicating the administered S-protein mRNA and likely mediated through an autoimmune mechanism. Nonetheless, other mechanisms may be implicated given the fact that myocarditis cases are very rarely observed among recipients of non mRNA vaccines.
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Shortly afterwards [release of the COVID vaccines] however, the first reports over a possible association between mRNA platform-based vaccinations and cases of myocarditis appeared. The clinical presentation as well as laboratory and imaging studies of these cases are compatible with that of acute myocarditis from other, commonly viral causes; cases typically present with chest pain with an onset usually within 3–4 days (and, in virtually all cases, within 14 days) following either BNT162b2 or mRNA-1273 vaccination, most frequently the second dose [13], [14], [15], [34]. Although both genders in a broad age spectrum may be affected, the risk appears to be highest among young males...
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With respect to the pathogenesis of mRNA vaccine-related myocarditis cases, a number of potential explanations have been attempted. In order to explain the skewed gender distribution of cases, the influence of sex steroid hormones (estrogen, testosterone) has been suggested. Not surprisingly, in the foreground stand immune or autoimmune mediated processes as possible mechanisms, and the highest frequency of occurrence after the second vaccine dose (after allowing for a presumed sensibilization process to take place after the first dose) seems to strengthen this notion.
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A previously overlooked component of the mRNA vaccines relates to the lipid nanoparticle sheath which encapsulates the mRNA strand encoding the S-protein sequence. The Moderna and Pfizer/BioNTech vaccines are not the first applications of this technology, since liposomal and nanoparticle formulations have already been used as drug delivery vehicles, particularly chemotherapeutics, for over two decades now.
Since myocarditis cases after Covid-19 vaccination are virtually exclusively confined among mRNA-based recipients, the question arises if specific lipid molecules or their combination in the structure of the lipid nanoparticle component of these vaccines could play a role in the pathogenesis of myocardial damage associated with their use. Within this context, a hypothesis could be made in the direction of either a direct deleterious effect on myocardial cells of LPN itself or of that of an immune reaction against it or even its aggregate with the mRNA strand within the vaccine preparations. One could argue that there have been up until now essentially no reports of a similar clinical picture among receivers of other non-vaccine, LPN-containing treatments (Fig. 1). This could be a mere result of the rarity of this adverse event combined with the massive vaccination programs, which could have allowed for the clustering and recognition of such cases. It should be also noted that the population most susceptible to vaccine-induced myocarditis, namely the younger age groups are typically underrepresented among those who receive treatment with lipid nanoparticle – formulated chemotherapeutics. Besides, the polyethylene glycol (PEG) component and several other ingredients of the LNP sheath have been also implicated in other hypersensitivity reactions, most notably in extremely rare but potentially life-threatening immediate cases of anaphylaxis following mRNA vaccine administration [28,29].
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With the need for a third mRNA-vaccine booster dose to sustain an adequate level of immunity against SARS-CoV-2 becoming increasingly apparent, it is likely that our knowledge with respect to the epidemiological and clinical features of vaccine-induced myocarditis will unfortunately continue to expand. This urgently calls for a deeper understanding of the exact pathogenetic mechanisms responsible for this rare entity, in order to reliably identify individuals at the highest risk for this rare complication and to accordingly adjust the corresponding vaccination strategies. In this context, the shift of investigation to include the lipid nanoparticle component of these platforms may constitute a field of particular relevance.