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Question...WHY WOULD AN IMMUNE CHALLENGE
SUCH AS VACCINATION, AFFECT BRAIN DEVELOPMENT AND/OR
FUNCTION ?
o “Until recently, the brain was studied almost exclusively by neuroscientists and the immune system by immunologists, fuelling the notion that these systems represented two isolated entities.
o ....the crosstalk between these systems can no longer be ignored and a new interdisciplinary approach is necessary.”
o Many proteins first identified in the immune system are also expressed in the developing and adult nervous system. Unexpectedly, recent studies reveal that a number of these proteins, in addition to their immunological roles, are essential for the establishment, function, and modification of synaptic connections.
o “Recent studies demonstrate that immune molecules are present at the right place and time to modulate the development and function of the healthy and diseased central nervous system (CNS).
o “...functions for immune molecules during neural development suggest that they could also mediate pathological responses to chronic elevations of cytokines in neurodevelopmental disorders, including autism spectrum disorders and schizophrenia.”
o “Despite the dogma that peripheral immune responses could not affect CNS function under normal circumstances, substantial evidence over the past 10 years suggests that immune-CNS cross-talk may be the norm rather than the exception.”
In: Handbook of Neurochemistry and Molecular Neurobiology: A Lajtha, HO Besedovsky, A Galoyan (Eds), Springer, 2008.
o Because the communication between the immune system and the brain occurs at multiple levels, this communication is now defined as a “immune–neuroendocrine network.”
o The immune–neuroendocrine network plays a key role in:‒ immune regulation‒ brain function‒ maintenance of general homeostasis
(circadian rhythms, endocrine and metabolic functions)
Disruption of the immune-neuroendocrine network leads to a wide range of diseases:
− neurological − immuno-inflammatory− metabolic disorders
What kind of disorder is autism?
“Increased oxidative stress and immune dysregulation are present in autism spectrum disorders.”
“We recently demonstrated the presence of neuroglial and innate neuroimmune system activation in brain tissue and cerebrospinal fluid of patients with autism, findings that support the view that neuroimmune abnormalities occur in the brain of autistic patients and may contribute to the diversity of the autistic phenotypes.”
o The evidence that changes in brain activity occur during the immune response implies that signals released by immune cells mediate these effects.
o peripheral immune insults can directly stimulate the synthesis of pro-inflammatory cytokines (i.e., IL-1β, IL-6, TNF)-α within the brain → brain inflammation
o It is clearly established that products derived from the immune system, particularly cytokines, affect neuroendocrine functions.
− Laye et al. Mol Brain Res 1994; 27:157-162− Besedovsky & Rey, Handbook of Neurochemistry and Molecular
Neurobiology, in: A. Lajtha, H.O. Besedovsky, A. Galoyan (Eds.), Springer, 2008
IMMUNE STIMULATION, IMMUNE CYTOKINES AND THEIR EFFECTS ON BRAIN ACTIVITY
− Endocrine functions− Autonomic functions− Growth, differentiation and repair−Neurotransmitter & neuropeptide synthesis & release− Neuronal activity and plasticity− Learning & memory− Behavior− Sleep− Pain− Food intake− Thermoregulation
Cytokines
NEUROENDOCRINE EFFECTS OF IMMUNE CYTOKINES
+ Endocrine functions
+ Autonomic functions
+ Growth, differentiation and repair
+ Neurotransmitter & neuropeptide synthesis & release
+ Neuronal activity and plasticity
NEUROENDOCRINE DEFFECTS IN AUTISM
+ Learning & memory
+ Behavior
+ Sleep
+ Pain
- Food intake- Thermoregulation
Is autism in part caused by a disruption of the immune-neuroendocrine network via elevation of pro-inflammatory mediators (cytokines)?
o We demonstrate an active neuroinflammatory process in the cerebral cortex, white matter, and cerebellum of autistic patients.
o Immunocytochemical studies showed marked activation of microglia and astroglia.
o Chemokines and cytokines MCP–1, IL-6 and TGF-1, derived from neuroglia, were the most prevalent cytokines in brain tissues.
o Cerebrospinal fluid showed a unique proinflammatory profile of cytokines, including a marked increase in MCP-1.
Which common peripheral immune insults other than infections can induce the synthesis of
pro-inflammatory cytokines in the brainand the activation of glial cells?
Duplicating the pediatric vaccine schedule with alum adjuvants in mice
2) Behavioral testing (social interaction) at 4-6 months of age3) Sacrifice and collecting of brain tissue at 6 months of age4) Semi-quantitative RT-PCR5) Western blot for protein levels
Treatment GroupMouse Age (days postnatal) Total Al injected
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 (ug/kg body weight)
High aluminum (US) 170 150 110 80 20 20 550
Low aluminum (SCA) 90 80 50 20 240
Control (saline) X X X X X X 0
1) Aluminum injection schedule:
Gene expression changes in male mice brains
Protein level changes in male mice brains
Genes affected in male mouse brains
Gene Function
NFKBIB NF-kappa-B inhibitor, which inhibits NF-kappa-B by complexing with, and trapping it in the cytoplasm. NF-κB is the central regulator of inflammation. Constitutive NF-κB activation is essential for macrophage survival.
ACHE Neurotransmitter (Ach) degradative enzyme, acetylcholinesterase. Anti-depression/anxiety effect. Low AChE activity is associated with deficits in neurodevelopment, particularly in attention and memory.
CCL2/MCP-1
Chemokine secreted by a few cell types including macrophage. A cytokine involved in immunoregulatory and inflammatory processes.
IFNG Interferon gamma, a secreted product and potent activator of macrophages. A soluble cytokine with antiviral, immunoregulatory and anti-tumor properties.
TNF Tumor necrosis factor mainly secreted by macrophages. Multifunctional proinflammatory cytokine.
Gene expression changes in female mice brains
BEHAVIORAL TESTS: LIGHT-DARK BOX
High aluminum group exhibits significantly increased anxiety & reduced exploratory behavior. Females are more severely affected, showing deficits even at low concentration of aluminum.
Males in the high aluminum group are significantly more lethargic than those in the low aluminum group & control mice.
BEHAVIORAL TESTS: OPEN FIELD
Object Mouse0
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CTRL femalesUS females
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Object Mouse0
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BEHAVIORAL TESTS: SOCIAL INTERACTIONS
REPEATED VACCINATIONS =
Stimulation of aberrant immune responses
Increased levels of inflammatory cytokines in the brain
IMPAIRED BRAIN DEVELOPMENT & FUNCTION
MOREOVER….
Repeated immunization with foreign antigen compounds causes systemic autoimmunity in mice otherwise not prone to spontaneous autoimmune diseases.
o CD4+ T cells from repeatedly-immunized mice acquire the ability to induce autoantibodies which results in autoimmune tissue injury similar to that seen in human autoimmune diseases.
o “SYSTEMIC AUTOIMMUNITY APPEARS TO BE THE INEVITABLE CONSEQUENCE OF OVER-STIMULATING THE HOST’S IMMUNE ‘SYSTEM’ BY REPEATED IMMUNIZATION WITH ANTIGEN.”
THE KEY PROBLEM IS NOT SINGLE VACCINESTHE KEY PROBLEM IS:
Other reasons why vaccines tend to adversely affect the central nervous system
o Vaccine-derived antigen-adjuvant (aluminum) complexes persist in the body long after injection (> 6 months)
o They are capable of penetrating the blood-brain barrier and triggering abnormal immuno-inflammatory reactions in the brain
34
Penetration of the blood-brain barrier by aluminum can allow access of antibodies to the brain and cause unwanted autoimmune reactions
Testing the hypothesis:
Is there experimental evidence to indicate that antibodies induced by the HPV vaccine
cross-react with neural antigens?
Gardasil
Mouse serumMouse brain protein extract
Gardasil antigens (HPV-16, 18, 11, 6)
Anti-HPV antibody
Anti – HPV antibody binds to HPVBrain extract inhibits Anti – HPV antibody
binding to HPV
Mouse serum
Brain extract m/ml
% I
nhib
ition
0
20
40
60
80
100
10 20 30 40 50
Gardasil + pertussis
Gardasil
Aluminum
Brain protein extract inhibits anti-HPV antibodies binding to HPV antigens
39
BRAIN
BLOOD
BLOOD-BRAIN BARRIER
HPV-16L1 Anti-HPV-16L1
Alum
AutoimmunityNeuro-inflammation
Macrophage
SUMMARY:The neurotoxic risk of the HPV vaccine
o Neurotoxic action of the aluminum adjuvant+
o Immuno-inflammatory effect of the HPV-16L1 vaccine antigen
+o Neuro-autoimmune effect of the cross-reactive HPV
vaccine-induced anti-HPV-16L1 antibody
40
Some vaccines as well as alum adjuvants can induce the release of IL-6 cytokine implicated in autism
o The whole cell pertussis vaccine induced high serum interleukin-6 levels in mice, while the acellular vaccine induced very low interleukin-6 levels, indicating that the whole bacterial cell is also important for interleukin-6 induction.
o Metals such as chromium, arsenic and particularly aluminum were elevated in the blood of an autistic child, as compared to reference values of a normal child.
o 70% of mothers took vaccine or injection and 80% of them ate canned food and fish during pregnancy. 90% babies received all recommended vaccines.
o In this study was possible to identify two important data regarding exposure to toxic metals. In 80% of cases the autistic children have used or make use of controlled drug and 90% of them have taken all vaccines.
o Hair scalp analysis of 1,967 subjects (0-15 years old, male and female), showed that 584 (29.7%) and 347 (17.6%) were deficient in zinc and magnesium.
o 339 (17.2%), 168 (8.5%) and 94 (4.8%) individuals were found to suffer from high burdens of aluminum, cadmium and lead, respectively, and 2.8% or less from mercury and arsenic.
The risks associated vaccine-derived Al are four-fold:
1) Al can persist in the body
2) Al can trigger pathological immunological responses
3) Al can make its way into the central nervous system where it can activate deleterious immuno-inflammatory and excitotoxic processes
4) Al can alter expression of numerous genes involved in the immuno-inflammatory responses and cell-to-cell signaling
o Effect of IL1 and IL6 on synaptic plasticity, learning and memory. In healthy conditions, IL1β supports learning acquisition and consolidation of hippocampal-dependant memory, while IL-6 exerts the opposite effect. When the concentration of IL1β and IL6 in the brain is increased during peripheral and central diseases, both cytokines tend to inhibit these processes.
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