A convergence of Kreuter's drug delivery mechanism, Gherardi's adjuvant biopersistence research, and Exley's findings of aluminum accumulation in autism brain tissue Abstract Background: Several widely used vaccine formulations simultaneously contain aluminum salts as adjuvants andpolysorbate 80 (PS80) as a surfactant. The pharmacological properties of each excipient have been independentlydocumented in the literature, yet their potential synergistic interaction has never been experimentally evaluated. Hypothesis: We propose that aluminum adjuvant nanoparticles present in vaccine formulations containing PS80may adsorb this surfactant onto their surface following injection. The resulting Al-PS80 complex may adsorbcirculating apolipoproteins — primarily ApoE and ApoB — and subsequently be transported into the brainparenchyma via receptor-mediated transcytosis across the blood-brain barrier (BBB), by the mechanism described byKreuter et al. for PS80-coated polymeric nanoparticles. Evidence base: Three independent lines of research support the biological plausibility of this hypothesis: (1) Kreuteret al. demonstrated that PS80-coated nanoparticles of diverse chemical composition adsorb apolipoproteins in vivo,enabling LDL receptor-mediated endocytosis at the cerebrovascular endothelium; (2) Gherardi et al. demonstratedthat vaccine aluminum particles exhibit long-term biopersistence and can translocate to the brain via intracellularphagocyte-mediated transport; (3) Mold, Umar, King and Exley (2018) reported some of the highest aluminumconcentrations ever measured in human brain tissue in donors with autism spectrum disorder, with aluminum foundpredominantly in microglia-like and non-neuronal inflammatory cells — a pattern consistent withphagocyte-mediated transport. The coexistence of both excipients in the same formulation — documented in Prevnar13/20, Gardasil 9, and several combined pediatric vaccines — creates conditions for the proposed interaction. Implications: If confirmed, this mechanism would represent an additional pathway for aluminum adjuvantneurodeposition, with particular relevance for infants receiving multiple doses of aluminum- and PS80-containingvaccines during the window of BBB maturation. A structurally analogous parallel hypothesis is articulated regardingPEGylated lipid nanoparticles (LNPs) in mRNA vaccines. Both hypotheses are falsifiable and amenable to directexperimental testing
Añaños et al. (Thu,) studied this question.