Question explored with the scientific record
Conversation so far
- 1 It's been shown that 2P-LNP spike is taken up by cells then repackaged into exosomes (Bansal). These exosomes can in turn enter - via transcytosis - other cells, including those lining the endothelium in the brain, (Maugeri). Thereafter it can theoretically continue to enter-transcytose and deliver spike protein beyond the BBB to astrocytes etc there. Please consider the findings published in "Insights into Exosome Transport through the BBB and the Potential Therapeutical Applications in Brain Diseases" published in Pharmaceuticals 2023. Texts state that exosomes conserve and protect a diverse matrix of neucleic acis, explicitly naming "messenger RNA (mRNA)" as a primary cargo successfully shuttled across the intracelluar compartments of brain microvascular endotheial cells via transcytosis. To what extent and how does this add evidential weight? + a private exchange
- 2 In 2023, "Exosomes Interactions withthe BBB: Implications for Cerebral disorders and Therapeutics" (Int Journal of Molec Sciences), establishes how systemic inflammation directly disrupts the neurovascular unit and accelerates exosome trafficking across the BBB, validating a pathway where a post-injection hyper-inflammatory or cytokine spike acts accelerator need to carry mRNA loaded vesicles into the CNS parenchmya? + a private exchange
- 3 Exosomes Interactions with the Blood-Brain Barrier: Implications for Cerebral Disorders and Therapeutics, Osaid et al Oct 2023, and "Insights into Exosome Transport through the Blood-Brain Barrier and the potential Therapeutic Apllications in Brain Diseases" Abdelsalam et al Apr 2023
Answered on this page ↓
Exosomes Interactions with the Blood-Brain Barrier: Implications for Cerebral Disorders and Therapeutics, Osaid et al Oct 2023, and "Insights into Exosome Transport through the Blood-Brain Barrier and the potential Therapeutic Apllications in Brain Diseases" Abdelsalam et al Apr 2023
The two 2023 reviews on exosome-BBB transport strengthen the case for mechanism, not for proof. They describe how exosomes cross — via receptor-mediated transcytosis, adsorptive-mediated uptake, and paracellular routes — but do not test whether LNP-delivered spike mRNA or protein enters human brain via exosomes.
The reviews are narrative reviews, not experimental studies. They cite the same pre-2023 literature on exosome biology, not new data on vaccine-derived exosomes. Neither study loaded spike mRNA into exosomes, injected them into humans, and tracked the cargo into cerebrospinal fluid or brain tissue. The mechanism they describe — an exosome's natural ability to cross at about 1-5% of injected dose in mouse models — is consistent but does not prove that a 2P-LNP injection produces enough circulating exosomes carrying functional spike to reach human brain parenchyma at a meaningful concentration.
| What the 2023 reviews establish | What they do not test |
|---|---|
| Exosomes cross BBB via known transport pathways | No experiment with spike-carrying exosomes in humans |
| mRNA cargo can be loaded into exosomes | No measurement of exosome cargo from vaccinated vs unvaccinated CSF |
| BBB disruption increases permeability | No direct quantification of brain spike protein from vaccination |
The retrieval gaps I noted in the previous answer remain. No study in this evidence measures spike-containing exosomes in human CSF after vaccination. The mechanism is biologically coherent on paper, but the hypothesis that 2P-LNP injection generates exosomes that carry functional spike across the human BBB is not tested by any study here.
My call: the 2023 reviews add plausibility, not proof. The specific claim remains untested in the evidence provided. Confidence: moderate.
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