Tossicità dell’alluminio adiuvante
Int J Environ Res Public Health. 2019 Jun 16;16(12). pii: E2129.
Aluminium in Brain Tissue in Epilepsy: A Case Report from Camelford.
Introduction: Human exposure to aluminium is a burgeoning problem. In 1988, the population of the Cornish town of Camelford was exposed to exceedingly high levels of aluminium in their potable water supply. Herein we provide evidence that aluminium played a role in the death of a Camelford resident following development of late-onset epilepsy. (2) Case summary: We have measured the aluminium content of brain tissue in this individual and demonstrated significant accumulations of aluminium in the hippocampus (4.35 (2.80) µg/g dry wt.) and the occipital lobe (2.22 (2.23) µg/g dry wt., mean, SD, n = 5), the latter being associated with abnormal calcifications. Aluminium-specific fluorescence microscopy confirmed the presence of aluminium in both of these tissues and made the consistent observation of aluminium-loaded glial cells in close proximity to aluminium-rich cell/neuronal debris. These observations support an inflammatory component in this case of late-onset epilepsy. Congo red failed to identify any amyloid deposits in any tissue while thioflavin S showed extensive extracellular and intracellular tau pathologies. (3) Discussion: We present the first data showing aluminium in brain tissue in epilepsy and suggest, in light of complementary evidence from scientific literature, the first evidence that aluminium played a role in the advent of this case of late-onset adult epilepsy.
https://www.mdpi.com/1660-4601/16/12/2129/htm
Front Chem. 2017 Jan 9;4:48.
From Stock Bottle to Vaccine: Elucidating the Particle Size Distributions of Aluminum Adjuvants Using Dynamic Light Scattering.
Shardlow E1, Mold M1, Exley C1.
The physicochemical properties of aluminum salts are key determinants of their resultant adjuvanticity in vivo when administered as part of a vaccine. While there are links between particle size and the efficacy of the immune response, the limited literature directly characterizing the PSD of aluminum adjuvants has stymied the elucidation of such a relationship for these materials. Hence, this comparative study was undertaken to monitor the PSD of aluminum adjuvants throughout the process of vaccine formulation using DLS. A significant proportion of the stock suspensions was highly agglomerated (>9 μm) and Alhydrogel® exhibited the smallest median size(2677 ± 120 nm) in comparison to Adju-Phos® or Imject alum® (7152 ± 308 and 7294 ± 146 nm respectively) despite its large polydispersity index (PDI). Dilution of these materials induced some degree of disaggregation within all samples with Adju-Phos® being the most significantly affected. The presence of BSA caused the median size of Alhydrogel® to increase but these trends were not evident when model vaccines were formulated with either Adju-Phos® or Imject alum®. Nevertheless, Alhydrogel® and Adju-Phos® exhibited comparable median sizes in the presence of this protein (4194 ± 466 and 4850 ± 501 nm respectively) with Imject alum® being considerably smaller (2155 ± 485 nm). These results suggest that the PSD of aluminum adjuvants is greatly influenced by dilution and the degree of protein adsorption experienced within the vaccine itself. The size of the resultant antigen-adjuvant complex may be important for its immunological recognition and subsequent clearance from the injection site.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5220009/
Morphologie 100, 160–161. (2016).
Low concentrations of aluminum hydroxide adjuvant, forming limited size aggregates, selectively induce cerebral aluminum increase and long-term neurotoxicity in mouse.
Crépeaux G., Eidi H., David M. O., Giros B., Authier F. J., Exley C., et al.
Background: Aluminium hydroxide (alum) has long been added as an adjuvant of vaccines. It consists of nanoparticles forming aggregates. Unexpectedly long-lasting biopersistence of alum aggregates were found within immune cells of patients with chronic fatigue, cognitive dysfunction, myalgias and dysimmunity [1], [2]. We documented in mice slow translocation of alum aggregates captured by monocyte-lineage cells from the injected muscle to brain [3], [4], [5]. Herein, brain function and aluminium (Al) concentration were examined long after injections.
Methods: Alhydrogel® was injected in TA muscle in adult female CD1 mice at 3 doses ranging from 133 to 800 μg Al/kg. Eight validated tests were used to evaluate cognitive and motor performances 180 days after injection. Brains were collected for Al level determination and Iba-1 immunohistochemistry.
Results: A most unusual neuro-toxicological pattern limited to lower doses of alum was observed. Neurobehavioral changes, including decreased activity levels and altered anxiety-like behaviour, were documented in animals exposed to the two lowest doses (133 and 200 μg Al/kg) but not at the highest dose (800 μg Al/kg), compared to controls. Consistently, cerebral Al levels were increased in animals exposed to the lowest doses. Microglial cell increase was found in amygdala of the 200 μg Al/kg group. Interestingly, the injected suspensions corresponding to the two lowest doses contained much smaller aggregates (1.50–1.75 μm) compared to the highest dose (4.70 μm).
Conclusion: Alum particles injected in muscle may induce neurotoxic effects and Al cerebral accumulation six months after injection in mice. Neurotoxic effects are restricted to low concentration suspensions forming small particle aggregates. Such bacteria-sized aggregates are known to be selectively captured by monocyte-lineage cells. This study strongly suggests that, in contrast to “the dose makes the poison” paradigm of classical toxicology, alum toxicology obeys the specific rules of small particle toxicology, thus deserving in depth revaluation. (This study was supported by ANSM).
Toxicology. 2017 Jan 15;375:48-57.
Non-linear dose-response of aluminium hydroxide adjuvant particles: Selective low dose neurotoxicity.
Crépeaux G1, Eidi H2, David MO3, Baba-Amer Y4, Tzavara E5, Giros B5, Authier FJ4, Exley C6, Shaw CA7, Cadusseau J8, Gherardi RK4.
Aluminium (Al) oxyhydroxide (Alhydrogel®), the main adjuvant licensed for human and animal vaccines, consists of primary nanoparticles that spontaneously agglomerate. Concerns about its safety emerged following recognition of its unexpectedly long-lasting biopersistence within immune cells in some individuals, and reports of chronic fatigue syndrome, cognitive dysfunction, myalgia, dysautonomia and autoimmune/inflammatory features temporally linked to multiple Al-containing vaccine administrations. Mouse experiments have documented its capture and slow transportation by monocyte-lineage cells from the injected muscle to lymphoid organs and eventually the brain. The present study aimed at evaluating mouse brain function and Al concentration 180 days after injection of various doses of Alhydrogel® (200, 400 and 800μg Al/kg of body weight) in the tibialis anterior muscle in adult female CD1 mice. Cognitive and motor performances were assessed by 8 validated tests, microglial activation by Iba-1 immunohistochemistry, and Al level by graphite furnace atomic absorption spectroscopy. An unusual neuro-toxicological pattern limited to a low dose of Alhydrogel® was observed. Neurobehavioural changes, including decreased activity levels and altered anxiety-like behaviour, were observed compared to controls in animals exposed to 200μg Al/kg but not at 400 and 800μg Al/kg. Consistently, microglial number appeared increased in the ventral forebrain of the 200μg Al/kg group. Cerebral Al levels were selectively increased in animals exposed to the lowest dose, while muscle granulomas had almost completely disappeared at 6 months in these animals. We conclude that Alhydrogel® injected at low dose in mouse muscle may selectively induce long-term Al cerebral accumulation and neurotoxic effects. To explain this unexpected result, an avenue that could be explored in the future relates to the adjuvant size since the injected suspensions corresponding to the lowest dose, but not to the highest doses, exclusively contained small agglomerates in the bacteria-size range known to favour capture and, presumably, transportation by monocyte-lineage cells. In any event, the view that Alhydrogel® neurotoxicity obeys "the dose makes the poison" rule of classical chemical toxicity appears overly simplistic.
NPJ Vaccines. 2018 Oct 10;3:51.
Optimizing the utilization of aluminum adjuvants in vaccines: you might just get what you want.
HogenEsch H1,2, O'Hagan DT3, Fox CB4,5.
Aluminum-containing adjuvants have been used for over 90 years to enhance the immune response to vaccines. Recent work has significantly advanced our understanding of the physical, chemical, and biological properties of these adjuvants, offering key insights on underlying mechanisms. Given the long-term success of aluminum adjuvants, we believe that they should continue to represent the "gold standard" against which all new adjuvants should be compared. New vaccine candidates that require adjuvants to induce a protective immune response should first be evaluated with aluminum adjuvants before other more experimental approaches are considered, since use of established adjuvants would facilitate both clinical development and the regulatory pathway. However, the continued use of aluminum adjuvants requires an appreciation of their complexities, in combination with access to the necessary expertise to optimize vaccine formulations. In this article, we will review the properties of aluminum adjuvants and highlight those elements that are critical to optimize vaccine performance. We will discuss how other components (excipients, TLR ligands, etc.) can affect the interaction between adjuvants and antigens, and impact the potency of vaccines. This review provides a resource and guide, which will ultimately contribute to the successful development of newer, more effective and safer vaccines
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6180056/
Int J Environ Res Public Health. 2019 Apr 24;16(8). pii: E1459.
Intracellular Aluminium in Inflammatory and Glial Cells in Cerebral Amyloid Angiopathy: A Case Report.
Mold M, Cottle J, King A, Exley C.
Introduction: In 2006, we reported on very high levels of aluminium in brain tissue in an unusual case of cerebral amyloid angiopathy (CAA). The individual concerned had been exposed to extremely high levels of aluminium in their potable water due to a notorious pollution incident in Camelford, Cornwall, in the United Kingdom. The recent development of aluminium-specific fluorescence microscopy has now allowed for the location of aluminium in this brain to be identified. (2) Case Summary: We used aluminium-specific fluorescence microscopy in parallel with Congo red staining and polarised light to identify the location of aluminium and amyloid in brain tissue from an individual who had died from a rare and unusual case of CAA. Aluminium was almost exclusively intracellular and predominantly in inflammatory and glial cells including microglia, astrocytes, lymphocytes and cells lining the choroid plexus. Complementary staining with Congo red demonstrated that aluminium and amyloid were not co-located in these tissues. (3) Discussion: The observation of predominantly intracellular aluminium in these tissues was novel and something similar has only previously been observed in cases of autism. The results suggest a strong inflammatory component in this case and support a role for aluminium in this rare and unusual case of CAA.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6518255/pdf/ijerph-16-01459.pdf
Allergy Asthma Clin Immunol. 2018 Nov 7;14:80.
Unraveling the enigma: elucidating the relationship between the physicochemical properties of aluminium-based adjuvants and their immunological mechanisms of action.
Aluminium salts are by far the most commonly used adjuvants in vaccines. There are only two aluminium salts which are used in clinically-approved vaccines, Alhydrogel® and AdjuPhos®, while the novel aluminium adjuvant used in Gardasil® is a sulphated version of the latter. We have investigated the physicochemical properties of these two aluminium adjuvants and specifically in milieus approximating to both vaccine vehicles and the composition of injection sites. Additionally we have used a monocytic cell line to establish the relationship between their physicochemical properties and their internalisation and cytotoxicity. We emphasise that aluminium adjuvants used in clinically approved vaccines are chemically and biologically dissimilar with concomitantly potentially distinct roles in vaccine-related adverse events.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6223008/pdf/13223_2018_Article_305.pdf
Vet Pathol. 2019 May;56(3):418-428.
Granulomas Following Subcutaneous Injection With Aluminum Adjuvant-Containing Products in Sheep.
Asín J1, Molín J1, Pérez M2, Pinczowski P1, Gimeno M1, Navascués N3, Muniesa A1, de Blas I1, Lacasta D1, Fernández A1, de Pablo L4, Mold M5, ExleyC5, de Andrés D4, Reina R4, Luján L1.
The use of vaccines including aluminum (Al)-based adjuvants is widespread among small ruminants and other animals. They are associated with the appearance of transient injection site nodules corresponding to granulomas. This study aims to characterize the morphology of these granulomas, to understand the role of the Al adjuvant in their genesis, and to establish the presence of the metal in regional lymph nodes. A total of 84 male neutered lambs were selected and divided into 3 treatment groups of 28 animals each: (1) vaccine (containing Al-based adjuvant), (2) adjuvant-only, and (3) control. A total of 19 subcutaneous injections were performed in a time frame of 15 months. Granulomas and regional lymph nodes were evaluated by clinicopathological means. All of the vaccine and 92.3% of the adjuvant-only lambs presented injection-site granulomas; the granulomas were more numerous in the group administered the vaccine. Bacterial culture in granulomas was always negative. Histologically, granulomas in the vaccine group presented a higher degree of severity. Al was specifically identified by lumogallion staining in granulomas and lymph nodes. Al median content was significantly higher ( P < .001) in the lymph nodes of the vaccine group (82.65 μg/g) compared with both adjuvant-only (2.53 μg/g) and control groups (0.96 μg/g). Scanning transmission electron microscopy demonstrated aggregates of Al within macrophages in vaccine and adjuvant-only groups. In these two groups, Al-based adjuvants induce persistent, sterile, subcutaneous granulomas with macrophage-driven translocation of Al to regional lymph nodes. Local translocation of Al may induce further accumulation in distant tissues and be related to the appearance of systemic signs.
Pediatr Dermatol. 2019 Jan;36(1):e17-e19.
Aluminum granuloma in a child secondary to DTaP-IPV vaccination: A case report.
Haag CK1, Dacey E2, Hamilton N3, White KP1.
Reports detailing the acute formation of aluminum granulomas, which can cause persistent, intensely pruritic nodules secondary to the administration of aluminum-containing vaccines, are infrequently described in medical literature. To our knowledge, this is the first report describing the development of an aluminum granuloma causing a persistent, pruritic nodule at the injection site following the administration of the DTaP-IPV vaccine. We present the case of a 6-year-old girl who developed a severely pruritic subcutaneous nodule on her anterior right thigh at the injection site three weeks after the administration of the aluminum-containing DTaP-IPV (Kinrix) vaccine. The nodule was eventually excised 14 months after its initial appearance, after which her symptoms resolved. Histologic inspection demonstrated a dense, deep dermal and subcutaneous nodular mixed infiltrate of lymphocytes, histiocytes, and eosinophils, with germinal center formation. The bluish, amphophilic granular cytoplasm found in most of the histiocytes is a characteristic feature of "aluminum granulomas." This adverse reaction should be considered in any patient presenting with similar findings in the weeks following a DTaP-IPV vaccination or other aluminum-containing vaccines. Furthermore, the self-limiting tendency of these nodules should not preclude affected patients from any future vaccinations, though vaccines without aluminum should be preferentially selected when possible.
Adv Exp Med Biol. 2018;1091:33-37.
The Chemistry of Human Exposure to Aluminium.
Exley C1.
Before it is possible to begin to understand the chemistry of human exposure to aluminium, it is necessary to appreciate a few basic rules. Rule number one tells us that the form of aluminium which is bound by functional groups on biomolecules is its free trivalent aqueous cation, Al3+ (aq). Rule number two tells us that the binding of Al3+ (aq) is determined by both thermodynamic and kinetic constraints. Rule number three tells us how essential it is to understand the critical importance of the exposure regime. The application of these simple rules of aluminium chemistry allows us to understand why, for example, not all aluminium salts are equal and not all routes of aluminium exposure are equivalent.
https://www.researchgate.net/publication/328237103_The_Chemistry_of_Human_Exposure_to_Aluminium
Int J E nviron Res Public Health. 2018 Aug 18;15(8).
Aluminium in Brain Tissue in Multiple Sclerosis.
Mold M1, Chmielecka A2, Rodriguez MRR3, Thom F4, Linhart C5, King A6, Exley C7.
Multiple sclerosis (MS) is a devastating and debilitating neurodegenerative disease of unknown cause. A consensus suggests the involvement of both genetic and environmental factors of which the latter may involve human exposure to aluminium. There are no data on the content and distribution of aluminium in human brain tissue in MS. The aluminium content of brain tissue from 14 donors with a diagnosis of MS was determined by transversely heated graphite furnace atomic absorption spectrometry. The location of aluminium in the brain tissue of two donors was investigated by aluminium-specific fluorescence microscopy. The aluminium content of brain tissue in MS was universally high with many tissues bearing concentrations in excess of 10 μg/g dry wt. (10 ppm) and some exceeding 50 ppm. There were no statistically significant relationships between brain lobes, donor age or donor gender. Aluminium-specific fluorescence successfully identified aluminium in brain tissue in both intracellular and extracellular locations. The association of aluminium with corpora amylacea suggests a role for aluminium in neurodegeneration in MS.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6121957/pdf/ijerph-15-01777.pdf
J Trace Elem Med Biol. 2018 Mar;46:76-82.
Aluminium in brain tissue in autism.
Mold M1, Umar D2, King A3, Exley C1.
Autism spectrum disorder is a neurodevelopmental disorder of unknown aetiology. It is suggested to involve both genetic susceptibility and environmental factors including in the latter environmental toxins. Human exposure to the environmental toxin aluminium has been linked, if tentatively, to autism spectrum disorder. Herein we have used transversely heated graphite furnace atomic absorption spectrometry to measure, for the first time, the aluminium content of brain tissue from donors with a diagnosis of autism. We have also used an aluminium-selective fluor to identify aluminium in brain tissue using fluorescence microscopy. The aluminium content of brain tissue in autism was consistently high. The mean (standard deviation) aluminium content across all 5 individuals for each lobe were 3.82(5.42), 2.30(2.00), 2.79(4.05) and 3.82(5.17) μg/g dry wt. for the occipital, frontal, temporal and parietal lobes respectively. These are some of the highest values for aluminium in human brain tissue yet recorded and one has to question why, for example, the aluminium content of the occipital lobe of a 15 year old boy would be 8.74 (11.59) μg/g dry wt.? Aluminium-selective fluorescence microscopy was used to identify aluminium in brain tissue in 10 donors. While aluminium was imaged associated with neurones it appeared to be present intracellularly in microglia-like cells and other inflammatory non-neuronal cells in the meninges, vasculature, grey and white matter. The pre-eminence of intracellular aluminium associated with non-neuronal cells was a standout observation in autism brain tissue and may offer clues as to both the origin of the brain aluminium as well as a putative role in autism spectrum disorder.
https://www.sciencedirect.com/science/article/pii/S0946672X17308763?via%3Dihub
J Trace Elem Med Biol. 2017 Mar;40:30-36.
Aluminium in brain tissue in familial Alzheimer's disease.
Mirza A1, King A2, Troakes C3, Exley C4.
The genetic predispositions which describe a diagnosis of familial Alzheimer's disease can be considered as cornerstones of the amyloid cascade hypothesis. Essentially they place the expression and metabolism of the amyloid precursor protein as the main tenet of disease aetiology. However, we do not know the cause of Alzheimer's disease and environmental factors may yet be shown to contribute towards its onset and progression. One such environmental factor is human exposure to aluminium and aluminium has been shown to be present in brain tissue in sporadic Alzheimer's disease. We have made the first ever measurements of aluminium in brain tissue from 12 donors diagnosed with familial Alzheimer's disease. The concentrations of aluminium were extremely high, for example, there were values in excess of 10μg/g tissue dry wt. in 5 of the 12 individuals. Overall, the concentrations were higher than all previous measurements of brain aluminium except cases of known aluminium-induced encephalopathy. We have supported our quantitative analyses using a novel method of aluminium-selective fluorescence microscopy to visualise aluminium in all lobes of every brain investigated. The unique quantitative data and the stunning images of aluminium in familial Alzheimer's disease brain tissue raise the spectre of aluminium's role in this devastating disease.
https://www.sciencedirect.com/science/article/pii/S0946672X16303777?via%3Dihub
Toxicology. 2017 Jan 15;375:48-57.
Non-linear dose-response of aluminium hydroxide adjuvant particles: Selective low dose neurotoxicity.
Crépeaux G1, Eidi H2, David MO3, Baba-Amer Y4, Tzavara E5, Giros B5, Authier FJ4, Exley C6, Shaw CA7, Cadusseau J8, Gherardi RK4.
Aluminium (Al) oxyhydroxide (Alhydrogel®), the main adjuvant licensed for human and animal vaccines, consists of primary nanoparticles that spontaneously agglomerate. Concerns about its safety emerged following recognition of its unexpectedly long-lasting biopersistence within immune cells in some individuals, and reports of chronic fatigue syndrome, cognitive dysfunction, myalgia, dysautonomia and autoimmune/inflammatory features temporally linked to multiple Al-containing vaccine administrations. Mouse experiments have documented its capture and slow transportation by monocyte-lineage cells from the injected muscle to lymphoid organs and eventually the brain. The present study aimed at evaluating mouse brain function and Al concentration 180days after injection of various doses of Alhydrogel® (200, 400 and 800μg Al/kg of body weight) in the tibialis anterior muscle in adult female CD1 mice. Cognitive and motor performances were assessed by 8 validated tests, microglial activation by Iba-1 immunohistochemistry, and Al level by graphite furnace atomic absorption spectroscopy. An unusual neuro-toxicological pattern limited to a low dose of Alhydrogel® was observed. Neurobehavioural changes, including decreased activity levels and altered anxiety-like behaviour, were observed compared to controls in animals exposed to 200μg Al/kg but not at 400 and 800μg Al/kg. Consistently, microglial number appeared increased in the ventral forebrain of the 200μg Al/kg group. Cerebral Al levels were selectively increased in animals exposed to the lowest dose, while muscle granulomas had almost completely disappeared at 6 months in these animals. We conclude that Alhydrogel® injected at low dose in mouse muscle may selectively induce long-term Al cerebral accumulation and neurotoxic effects. To explain this unexpected result, an avenue that could be explored in the future relates to the adjuvant size since the injected suspensions corresponding to the lowest dose, but not to the highest doses, exclusively contained small agglomerates in the bacteria-size range known to favour capture and, presumably, transportation by monocyte-lineage cells. In any event, the view that Alhydrogel® neurotoxicity obeys "the dose makes the poison" rule of classical chemical toxicity appears overly simplistic.
Morphologie. 2016 Jun;100(329):85-94.
Aluminum adjuvants of vaccines injected into the muscle: Normal fate, pathology and associated disease.
Gherardi RK1, Aouizerate J1, Cadusseau J2, Yara S2, Authier FJ3.
Aluminum oxyhydroxide (Alhydrogel(®)) is a nano-crystalline compound forming aggregates that has been introduced in vaccine for its immunologic adjuvant effect in 1926. It is the most commonly used adjuvant in human and veterinary vaccines but mechanisms by which it stimulates immune responses remain ill-defined. Although generally well tolerated on the short term, it has been suspected to occasionally cause delayed neurologic problems in susceptible individuals. In particular, the long-term persistence of aluminic granuloma also termed macrophagic myofasciitis is associated with chronic arthromyalgias and fatigue and cognitive dysfunction. Safety concerns largely depend on the long biopersistence time inherent to this adjuvant, which may be related to its quick withdrawal from the interstitial fluid by avid cellular uptake; and the capacity of adjuvant particles to migrate and slowly accumulate in lymphoid organs and the brain, a phenomenon documented in animal models and resulting from MCP1/CCL2-dependant translocation of adjuvant-loaded monocyte-lineage cells (Trojan horse phenomenon). These novel insights strongly suggest that serious re-evaluation of long-term aluminum adjuvant phamacokinetics and safety should be carried out.
BMC Med. 2013 Apr 4;11:99
Slow CCL2-dependent translocation of biopersistent particles from muscle to brain.
Khan Z1, Combadière C, Authier FJ, Itier V, Lux F, Exley C, Mahrouf-Yorgov M, Decrouy X, Moretto P, Tillement O, Gherardi RK, Cadusseau J.
BACKGROUND: Long-term biodistribution of nanomaterials used in medicine is largely unknown. This is the case for alum, the most widely used vaccine adjuvant, which is a nanocrystalline compound spontaneously forming micron/submicron-sized agglomerates. Although generally well tolerated, alum is occasionally detected within monocyte-lineage cells long after immunization in presumably susceptible individuals with systemic/neurologic manifestations or autoimmune (inflammatory) syndrome induced by adjuvants (ASIA).
METHODS: On the grounds of preliminary investigations in 252 patients with alum-associated ASIA showing both a selective increase of circulating CCL2, the major monocyte chemoattractant, and a variation in the CCL2 gene, we designed mouse experiments to assess biodistribution of vaccine-derived aluminum and of alum-particle fluorescent surrogates injected in muscle. Aluminum was detected in tissues by Morin stain and particle induced X-ray emission) (PIXE) Both 500 nm fluorescent latex beads and vaccine alum agglomerates-sized nanohybrids (Al-Rho) were used.
RESULTS: Intramuscular injection of alum-containing vaccine was associated with the appearance of aluminum deposits in distant organs, such as spleen and brain where they were still detected one year after injection. Both fluorescent materials injected into muscle translocated to draining lymph nodes (DLNs) and thereafter were detected associated with phagocytes in blood and spleen. Particles linearly accumulated in the brain up to the six-month endpoint; they were first found in perivascular CD11b+ cells and then in microglia and other neural cells. DLN ablation dramatically reduced the biodistribution. Cerebral translocation was not observed after direct intravenous injection, but significantly increased in mice with chronically altered blood-brain-barrier. Loss/gain-of-function experiments consistently implicated CCL2 in systemic diffusion of Al-Rho particles captured by monocyte-lineage cells and in their subsequent neurodelivery. Stereotactic particle injection pointed out brain retention as a factor of progressive particle accumulation.
CONCLUSION: Nanomaterials can be transported by monocyte-lineage cells to DLNs, blood and spleen, and, similarly to HIV, may use CCL2-dependent mechanisms to penetrate the brain. This occurs at a very low rate in normal conditions explaining good overall tolerance of alum despite its strong neurotoxic potential. However, continuously escalating doses of this poorly biodegradable adjuvant in the population may become insidiously unsafe, especially in the case of overimmunization or immature/altered blood brain barrier or high constitutive CCL-2 production.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3616851/pdf/1741-7015-11-99.pdf
Adv Exp Med Biol. 2018;1091:53-83.
Aluminum as a CNS and Immune System Toxin Across the Life Span.
Shaw CA1.
In the following, I will consider the impact of aluminum on two major systems, the central nervous system (CNS) and the immune system, across the lifespan. The article will discuss the presence of aluminum in the biosphere, its history, and the sources of the element. These include food, water cosmetics, some vaccines, and a range of other sources. I will also consider aluminum's unique chemistry. Finally, in humans and animals, I will consider how aluminum may impact the CNS at various levels of organization and how it may be involved in various neurological disease states across the lifespan. These disorders include those of infancy and childhood, such as autism spectrum disorder (ASD), as well as those in adulthood, such as in Alzheimer's disease. The bidirectional nature of CNS-immune system interactions will be considered and put into the context of neurological disorders that have an autoimmune component. I will argue that the exposure to humans and animals to this element needs to be reduced if we are to diminish some CNS and immune system disorders.
https://www.ncbi.nlm.nih.gov/pubmed/30315449
J Trace Elem Med Biol. 2018 Jul;48:67-73.
Reconsideration of the immunotherapeutic
pediatric safe dose levels of aluminum.
Lyons-Weiler J1, Ricketson R2.
FDA regulations require safety testing of constituent ingredients in drugs (21 CFR 610.15). With the exception of extraneous proteins, no component safety testing is required for vaccines or vaccine schedules. The dosing of aluminum in vaccines is based on the production of antibody titers, not safety science. Here we estimate a Pediatric Dose Limit that considers body weight. We identify several serious historical missteps in past analyses of provisional safe levels of aluminum in vaccines, and provide updates relevant to infant aluminum exposure in the pediatric schedule considering pediatric body weight. When aluminum doses are estimated from Federal Regulatory Code given body weight, exposure from the current vaccine schedule are found to exceed our estimate of a weight-corrected Pediatric Dose Limit. Our calculations show that the levels of aluminum suggested by the currently used limits place infants at risk of acute, repeated, and possibly chronic exposures of toxic levels of aluminum in modern vaccine schedules. Individual adult exposures are on par with Provisional Tolerable Weekly Intake "limits", but some individuals may be aluminum intolerant due to genetics or previous exposures. Vaccination in neonates and low birth-weight infants must be re-assessed; other implications for the use of aluminum-containing vaccines, and additional limitations in our understanding of neurotoxicity and safety levels of aluminum in biologics are discussed.
https://www.sciencedirect.com/science/article/pii/S0946672X17300950
J Inorg Biochem. 2018 Apr;181:87-95.
Critical analysis of reference studies on the toxicokinetics of aluminum-based adjuvants.
Masson JD1, Crépeaux G2, Authier FJ1, Exley C3, Gherardi RK4.
We reviewed the three toxicokinetic reference studies commonly used to suggest that aluminum (Al)-based adjuvants are innocuous. A single experimental study was carried out using isotopic 26Al (Flarend et al., Vaccine, 1997). This study used aluminum salts resembling those used in vaccines but ignored adjuvant uptake by cells that was not fully documented at the time. It was conducted over a short period of time (28 days) and used only two rabbits per adjuvant. At the endpoint, Al elimination in the urine accounted for 6% for Al hydroxide and 22% for Al phosphate, both results being incompatible with rapid elimination of vaccine-derived Al in urine. Two theoretical studies have evaluated the potential risk of vaccine Al in infants, by reference to an oral "minimal risk level" (MRL) extrapolated from animal studies. Keith et al. (Vaccine, 2002) used a high MRL (2mg/kg/d), an erroneous model of 100% immediate absorption of vaccine Al, and did not consider renal and blood-brain barrier immaturity. Mitkus et al. (Vaccine, 2011) only considered solubilized Al, with erroneous calculations of absorption duration. Systemic Al particle diffusion and neuro-inflammatory potential were omitted. The MRL they used was both inappropriate (oral Al vs. injected adjuvant) and still too high (1mg/kg/d) regarding recent animal studies. Both paucity and serious weaknesses of reference studies strongly suggest that novel experimental studies of Al adjuvants toxicokinetics should be performed on the long-term, including both neonatal and adult exposures, to ensure their safety and restore population confidence in Al-containing vaccines.
https://www.ncbi.nlm.nih.gov/pubmed/29307441
Biol Trace Elem Res. 2018 Jun;183(2):314-324.
How Bad Is Aluminum Exposure to Reproductive Parameters in Rats?
Mouro VGS1, Menezes TP1, Lima GDA1, Domingues RR1, Souza ACF1, Oliveira JA1, Matta SLP1, Machado-Neves M2.
Aluminum (Al) is the most widely distributed metal in the environment and is extensively used in human daily life without any known biological function. It is known that exposure to high concentrations of Al impacts negatively on serum testosterone levels, testicular histomorphometry, and sperm parameters; however, no information is available about the effects of low exposure levels on reproduction. International organizations have established the Al concentration tolerated in drinking water as 3.35 × 10-4 mg/kg. Therefore, we aimed to compare the effects of long-term exposure to low and high concentrations of Al on male reproductive functions, focusing on testis, epididymis, and sperm parameters. Adult Wistar rats were exposed to aluminum chloride (AlCl3) at 6.7 × 10-5, 3.35 × 10-4, 10, and 40 mg/kg for 112 days by gavage. Al-exposed animals presented low values of testis and epididymis weight, and serum testosterone levels when compared to controls. The stereology of Leydig cells, epididymis histomorphometry, sperm motility, and structural integrity of sperm membranes changed depending on the Al concentration. In regard to epididymis histomorphometry, the initial segment and caput regions were more affected by Al exposure than distal regions. Otherwise, the histology of testis and epididymis did not alter after the Al exposure, as well as sperm morphology. In summary, we concluded that the consequences of Al exposure at low levels were as negative as high levels on reproductive parameters, suggesting adverse impact on male fertility.
J Inorg Biochem. 2018 Apr;181:96-103.
Is exposure to aluminium adjuvants associated with social impairments in mice? A pilot study.
BACKGROUND: Our group has shown that significant correlations exist between rates of Autism Spectrum Disorder (ASD) and total aluminum adjuvants given to children through vaccines in several Western countries. These correlations satisfied eight out of nine Hill criteria for causality. Experimental studies have demonstrated a range of behavioural abnormalities in young mice after postnatal exposure to aluminium. To build on our previous work, the current study will investigate the effect of aluminium adjuvants on social behaviour in mice. Anomalies in social interaction are a key characteristic of those with ASD.
METHODS: Neonatal CD-1 mice pups were injected with either a total of 550μg of aluminum hydroxide gel (experimental group) or saline (control) spread out during the first two weeks of postnatal life. The mice were then subjected to behavioural tests for social interest and social novelty at postnatal week 8, 17 and 29. p-Values were calculated using the Mann-Whitney and Kruskal Wallis tests.
RESULTS: Aluminum injected mice showed diminished social interest compared to controls at week 8 (p=0.016) and 17 (p=0.012). They also demonstrated abnormal social novelty from controls at week 8 (p=0.002) and week 29 (p=0.042).
CONCLUSION: This is the first experimental study, to our knowledge, to demonstrate that aluminum adjuvants can impair social behaviour if applied in the early period of postnatal development. The study, however, is insufficient to make any assertive claims about the link between aluminium adjuvants and ASD in humans.
https://www.ncbi.nlm.nih.gov/pubmed/29221615
J Inorg Biochem. 2015 Nov;152:199-205.
Highly delayed systemic translocation of aluminum-based adjuvant in CD1 mice following intramuscular injections.
Crépeaux G, Eidi H, David MO, Tzavara E, Giros B, Exley C, Curmi PA, Shaw CA, Gherardi RK, Cadusseau J.
Concerns regarding vaccine safety have emerged following reports of potential adverse events in both humans and animals. In the present study, alum, alum-containing vaccine and alum adjuvant tagged with fluorescent nanodiamonds were used to evaluate i) the persistence time at the injection site, ii) the translocation of alum from the injection site to lymphoid organs, and iii) the behavior of adult CD1 mice following intramuscular injection of alum (400 μg Al/kg). Results showed for the first time a strikingly delayed systemic translocation of adjuvant particles. Alum-induced granuloma remained for a very long time in the injected muscle despite progressive shrinkage from day 45 to day 270. Concomitantly, a markedly delayed translocation of alum to the draining lymph nodes, major at day 270 endpoint, was observed. Translocation to the spleen was similarly delayed (highest number of particles at day 270). In contrast to C57BL/6J mice, no brain translocation of alum was observed by day 270 in CD1 mice. Consistently neither increase of Al cerebral content, nor behavioral changes were observed. On the basis of previous reports showing alum neurotoxic effects in CD1 mice, an additional experiment was done, and showed early brain translocation at day 45 of alum injected subcutaneously at 200 μg Al/kg. This study confirms the striking biopersistence of alum. It points out an unexpectedly delayed diffusion of the adjuvant in lymph nodes and spleen of CD1 mice, and suggests the importance of mouse strain, route of administration, and doses, for future studies focusing on the potential toxic effects of aluminum-based adjuvants.
https://www.ncbi.nlm.nih.gov/pubmed/26384437
Toxicology. 2017 Sep 1;390:10-21.
Aluminum exposure at human dietary levels promotes vascular dysfunction and increases blood pressure in rats: A concerted action of NAD(P)H oxidase and COX-2.
Martinez CS, Piagette JT, Escobar AG, Martín Á, Palacios R, Peçanha FM, Vassallo DV, Exley C, Alonso MJ, Miguel M, Salaices M, Wiggers GA.
Aluminum (Al) is a non-essential metal and a significant environmental contaminant and is associated with a number of human diseases including cardiovascular disease. We investigated the effects of Al exposure at doses similar to human dietary levels on the cardiovascular system over a 60 day period. Wistar male rats were divided into two major groups and received orally: 1) Low aluminum level - rats were subdivided and treated for 60 days as follows: a) Untreated - ultrapure water; b) AlCl3 at a dose of 8.3mg/kg bw for 60 days, representing human Al exposure by diet; and 2) High aluminum level - rats were subdivided and treated for 42 days as follows: C) Untreated - ultrapure water; d) AlCl3 at 100mg/kg bw for 42 days, representing a high level of human exposure to Al. Effects on systolic blood pressure (SBP) and vascular function of aortic and mesenteric resistance arteries (MRA) were studied. Endothelium and smooth muscle integrity were evaluated by concentration-response curves to acetylcholine (ACh) and sodium nitroprusside. Vasoconstrictor responses to phenylephrine (Phe) in the presence and absence of endothelium and in the presence of the NOS inhibitor L-NAME, the potassium channels blocker TEA, the NAD(P)H oxidase inhibitor apocynin, superoxide dismutase (SOD), the non-selective COX inhibitor indomethacin and the selective COX-2 inhibitor NS 398 were analyzed. Vascular reactive oxygen species (ROS), lipid peroxidation and total antioxidant capacity, were measured. The mRNA expressions of eNOS, NAD(P)H oxidase 1 and 2, SOD1, COX-2 and thromboxane A2 receptor (TXA-2 R) were also investigated. Al exposure at human dietary levels impaired the cardiovascular system and these effects were almost the same as Al exposure at much higher levels. Al increased SBP, decreased ACh-induced relaxation, increased response to Phe, decreased endothelial modulation of vasoconstrictor responses, the bioavailability of nitric oxide (NO), the involvement of potassium channels on vascular responses, as well as increased ROS production from NAD(P)H oxidase and contractile prostanoids mainly from COX-2 in both aorta and mesenteric arteries. Al exposure increased vascular ROS production and lipid peroxidation as well as altered the antioxidant status in aorta and MRA. Al decreased vascular eNOS and SOD1 mRNA levels and increased the NAD(P)H oxidase 1, COX-2 and TXA-2 R mRNA levels. Our results point to an excess of ROS mainly from NAD(P)H oxidase after Al exposure and the increased vascular prostanoids from COX-2 acting in concert to decrease NO bioavailability, thus inducing vascular dysfunction and increasing blood pressure. Therefore, 60-day chronic exposure to Al, which reflects common human dietary Al intake, appears to pose a risk for the cardiovascular system.
https://www.ncbi.nlm.nih.gov/pubmed/28826906
J Toxicol. 2014;2014:491316.
Aluminum-induced entropy in biological systems: implications for neurological disease.
Shaw CA, Seneff S, Kette SD, Tomljenovic L, Oller JW Jr, Davidson RM.
Over the last 200 years, mining, smelting, and refining of aluminum (Al) in various forms have increasingly exposed living species to this naturally abundant metal. Because of its prevalence in the earth's crust, prior to its recent uses it was regarded as inert and therefore harmless. However, Al is invariably toxic to living systems and has no known beneficial role in any biological systems. Humans are increasingly exposed to Al from food, water, medicinals, vaccines, and cosmetics, as well as from industrial occupational exposure. Al disrupts biological self-ordering, energy transduction, and signaling systems, thus increasing biosemiotic entropy. Beginning with the biophysics of water, disruption progresses through the macromolecules that are crucial to living processes (DNAs, RNAs, proteoglycans, and proteins). It injures cells, circuits, and subsystems and can cause catastrophic failures ending in death. Al forms toxic complexes with other elements, such as fluorine, and interacts negatively with mercury, lead, and glyphosate. Al negatively impacts the central nervous system in all species that have been studied, including humans. Because of the global impacts of Al on water dynamics and biosemiotic systems, CNS disorders in humans are sensitive indicators of the Al toxicants to which we are being exposed.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4202242/pdf/JT2014-491316.pdf
J Toxicol. 2014;2014:491316.
Aluminum-induced entropy in biological systems: implications for neurological disease.
Shaw CA, Seneff S, Kette SD, Tomljenovic L, Oller JW Jr, Davidson RM.
Over the last 200 years, mining, smelting, and refining of aluminum (Al) in various forms have increasingly exposed living species to this naturally abundant metal. Because of its prevalence in the earth's crust, prior to its recent uses it was regarded as inert and therefore harmless. However, Al is invariably toxic to living systems and has no known beneficial role in any biological systems. Humans are increasingly exposed to Al from food, water, medicinals, vaccines, and cosmetics, as well as from industrial occupational exposure. Al disrupts biological self-ordering, energy transduction, and signaling systems, thus increasing biosemiotic entropy. Beginning with the biophysics of water, disruption progresses through the macromolecules that are crucial to living processes (DNAs, RNAs, proteoglycans, and proteins). It injures cells, circuits, and subsystems and can cause catastrophic failures ending in death. Al forms toxic complexes with other elements, such as fluorine, and interacts negatively with mercury, lead, and glyphosate. Al negatively impacts the central nervous system in all species that have been studied, including humans. Because of the global impacts of Al on water dynamics and biosemiotic systems, CNS disorders in humans are sensitive indicators of the Al toxicants to which we are being exposed.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4202242/pdf/JT2014-491316.pdf