title: Insight into the cellular fate and toxicity of aluminium adjuvants used in clinically approved human vaccinations.
abstract: Aluminium adjuvants remain the most widely used and effective adjuvants in vaccination and immunotherapy. Herein, the particle size distribution (PSD) of aluminium oxyhydroxide and aluminium hydroxyphosphate adjuvants was elucidated in attempt to correlate these properties with the biological responses observed post vaccination. Heightened solubility and potentially the generation of Al(3+) in the lysosomal environment were positively correlated with an increase in cell mortality in vitro, potentially generating a greater inflammatory response at the site of simulated injection. The cellular uptake of aluminium based adjuvants (ABAs) used in clinically approved vaccinations are compared to a commonly used experimental ABA, in an in vitro THP-1 cell model. Using lumogallion as a direct-fluorescent molecular probe for aluminium, complemented with transmission electron microscopy provides further insight into the morphology of internalised particulates, driven by the physicochemical variations of the ABAs investigated. We demonstrate that not all aluminium adjuvants are equal neither in terms of their physical properties nor their biological reactivity and potential toxicities both at the injection site and beyond. High loading of aluminium oxyhydroxide in the cytoplasm of THP-1 cells without immediate cytotoxicity might predispose this form of aluminium adjuvant to its subsequent transport throughout the body including access to the brain.
authors: The Birchall Centre, Lennard-Jones Laboratories, Keele University, Keele, Staffordshire, ST5 5BG, UK.
authors: Matthew
authors: M
authors: Mold
authors: The Birchall Centre, Lennard-Jones Laboratories, Keele University, Keele, Staffordshire, ST5 5BG, UK.
authors: Emma
authors: E
authors: Shardlow
authors: The Birchall Centre, Lennard-Jones Laboratories, Keele University, Keele, Staffordshire, ST5 5BG, UK.
authors: Christopher
authors: C
authors: Exley
mesh_terms: D000276:Adjuvants, Immunologic / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology; D000535:Aluminum / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology; D000536:Aluminum Hydroxide / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology; D016923:Cell Death / Q000187:drug effects; D006801:Humans; D008247:Lysosomes / Q000378:metabolism* / Q000473:pathology; D010316:Particle Size; D010710:Phosphates / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology; D000074084:THP-1 Cells; D014611:Vaccination
chemical_list: D000276:Adjuvants, Immunologic; D010710:Phosphates; D000536:Aluminum Hydroxide; C069096:aluminum hydroxyphosphate; D000535:Aluminum