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Vaccines and Autism
왗your lab focus 왘
10. Peters A. Experiments on the mechanism of silver
staining. II. Development. Quart J Microsc Sci.
1955;96:103-115.
11. Kiernan JA. Silver staining of axons in subcellular
fractions of nervous tissue. Experientia. 1970;26:1352.
12. Grizzle WE. Theory and practice of silver staining in
histopathology. J Histotechnol. 1996;19(3):183-195.
13. Clark G. Staining Procedures used by the Biological
Stain Commission. 4th ed. Baltimore: Williams &
Wilkins, 1981.
14. Garvey W. Silver impregnation techniques to identify
spirochetes and other bacteria. J Histotechnol.
1996;19:203-209.
15. Churukian CJ. Manual of the Special Stains
Laboratory. Rochester, NY: University of Rochester
Medical Center, 2000.
16. Holmes W. Silver staining of nerve axons in paraffin
sections. Anat Rec. 1943;86:157-187.
17. Samuel EP. The mechanism of silver staining. J Anat.
1953;87:278-287.
18. Peters A. Experiments on the mechanism of silver
staining. III. Electron microscope studies. Quart J
Microsc Sci. 1955;96:317-322.
19. James TH, ed. The Theory of the Photographic
Process. 4th ed. New York: Macmillan, 1977.
20. Giolli RA. A note on the chemical mechanism of the
Nauta-Gygax technique. J Histochem Cytochem.
1965;13:206-210.
21. Wolman M. Studies of the impregnation of nervous
tissue elements. II. The nature of the compounds
responsible for the impregnation of axons; practical
considerations. Quart J Microsc Sci.
1955;96:337-341.
22. Horobin RW, Bancroft JD. Troubleshooting Histology
Stains. Edinburgh, Scotland: Churchill Livingstone,
1998.
23. Lillie RD, Fullmer HM. Histopathologic Technic and
Practical Histochemistry. 4th ed. New York:
McGraw-Hill, 1976.
24. Peters A. A general-purpose method of silver staining.
Quart J Microsc Sci. 1955;96:323-328.
25. Gallyas F. A principle for silver staining of tissue
elements by physical development. Acta Morphol
Acad Sci Hung. 1971;19:57-71.
26. Garvey W. Some favorite silver stains. J Histotechnol.
1996;19:269-278.
27. McClung CE, ed. Handbook of Microscopical
Technique. New York: Hoeber, 1929.
overview [immunology | generalist]
Bernard Rimland, PhD, Woody McGinnis, MD
Autism Research Institute, San Diego, CA
왘 Autism research is characterized by
왘
왘
708
diverse findings.
There is no consensus about the
biological determinants of autism.
This paper examines the autistic
immune profile and the possible role
of vaccines in autism.
Vaccinations may be one of the triggers for autism. Substantial data demonstrate immune abnormality in many
autistic children consistent with impaired
resistance to infection, activation of inflammatory response, and autoimmunity.
Impaired resistance may predispose to
vaccine injury in autism.
A mercurial preservative in childhood
vaccines, thimerosal, may cause direct
neurotoxic, immunodepressive, and autoimmune injury and contribute to earlyonset and regressed autism. Live viruses
in measles, mumps, and rubella (MMR)
may result in chronic infection of the gut
and trigger regressed autism. Thimerosal
injection may potentiate MMR injury.
Consideration of vaccine etiology
must include recognition of compromised
gut and nutrition in most autistic children.
An integrated view of the underlying biological problems in autistic children
serves our understanding of the possible
role of vaccines. Development of screen-
ing methods for deferral of vaccines in atrisk children is a worthy goal.
gressed) autism. Impaired resistance to
infection and autoimmune diathesis may
provide fertile ground for vaccine injury,
and these conditions may exist prior to
both vaccination and the onset of autism.
A shift in the age of onset suggests
an operative environmental factor. Thousands of parent reports collected during
nearly 40 years by the Autism Research
Institute demonstrate a reversal in the relative proportions of early versus regressed
autism. General trends, rather than precise
inflection points, are derived from this
parental data. It is clear that the proportion
of autistic children who enjoyed normal
neurobehavioral development and then
regressed, usually in the second year of
life, has been on the rise for about 2
decades. New vaccines, including combined MMR, hepatitis B, and
Haemophilus influenza are new environmental factors that were introduced during
this period of changing onset.
A mercurial preservative,
thimerosal, is a vestige of l930s vaccine
technology and lacks full safety testing.
Thimerosal-containing vaccines include:
Rh-immunoglobulin during gestation;
hepatitis B (Hep-B) at birth; diptheria,
and tetanus toxoids with acellular pertussis (DTaP) at 2 month intervals after
birth; and Haemophilus influenza type b
Background
The psychiatric model for autism
has been replaced by the concept of biological causation, but there is no scientific consensus about the biological
determinants. The clinical expression of
autistic spectrum disorders is heterogenous, and it is likely that multiple predispositions and triggers exist for the
illness. An increasing number of people,
including many physician-parents of
autistic children, suspect that vaccinations may be one of the triggers.
Long-term prospective studies of the
behavioral and neurodevelopmental effects of vaccination do not exist. There is
controversy surrounding the mechanism,
accuracy, and interpretation of epidemiological studies examining the possible association of autism and vaccinations. The
existing body of relevant laboratory and
pathological data in autism is therefore of
particular interest.
A host of data reflect abnormal immune patterns in autism, consistent with
impaired resistance to infection and activation of the inflammatory response.
These laboratory studies do not
distinguish early-onset and late-onset (re-
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Vaccines and Autism
왗your lab focus 왘
The Autistic Immune Profile
Laboratory studies of autistic children
demonstrate 1) decreased immune indices,
2) activation of the inflammatory immune
system, and 3) increased markers for autoimmunity. Laboratory studies in these
areas have not been obtained in children
prior to autistic regression. Clinicians do
suspect more upper respiratory and gastrointestinal infections in children prior to
autistic regression. Increased genotypic
markers exist in subsets of the autistic
population for both impaired resistance to
infection and autoimmune diathesis.
A Pattern of Depressed
Resistance in Autism
T lymphocytes (T cells) are abnormal in many autistic children.
Cytokines from T cells regulate the full
spectrum of antibody and cell-mediated
response, the latter being particularly
important in resistance to viral infections. Both numeric and functional Tcell deficiencies are demonstrated in
autistic children. Autistic children have
significantly reduced total T-cell and
CD4+ lymphocyte subset counts compared with controls.1-3 Low numbers of
CD4+ cells are found in 28% of autistic
children, and 32% have low proportions
of CD4+.4 Functional deficits in T cells
may be even more significant than low
numbers. T cells from autistic children
have diminished function,5 with
extremely poor blastogenic response to
multiple mitogens [P<.001],2 perhaps
due to a CD4+ deficit.4
B-lymphocyte (B cell) deficits are
quite common in autism, with low numbers of CD20+ in 48% of autistic children.4 Effective antibody formation by B
cells is particularly important in resistance to bacteria, mycoplasmas, and enteroviruses. Low IgG subclass levels are
reported in 20% of autistic children,1 and
low IgA levels are reported in 20% of
autistic children in 2 independent
studies.4,6 Intravenous immunoglobulin
treatments have benefited autistic children
both with and without IgG subclass deficiency, perhaps by countering infections
or autoimmune processes.4
Natural killer (NK) cell abnormality
is found in autism. Natural killer cells
are specialized lymphocytes that act
against infected or otherwise defective
host cells. Low numbers of CD3CD16+ NK cells are found in 24% of
autistic children, with decreased proportions of CD3-CD16+ NK cells in
©
45%.4 Seventy-five percent of children
with Rett syndrome, very similar to
autism, have low numbers of NK cells.7
Forty percent of autistic subjects have
low NK-cell cytotoxic function.8
Lower C4 complements levels are
found in autism and this is consistent
with a higher frequency of C4A null allele in the autistic population (58%)
compared with controls (27%).9 The
C4A null allele is associated with
increased viral and bacterial infections6
and autoimmune disease.9
Combined immune defects are common in autism. Sixty-four percent of
autistic children had measurable deficit in
at least 1 of 3 cell lines (CD4+ T cells,
CD20+ B cells, CD16+ NK cells).4 A
better understanding of the role of clustered immune deficits in autism is
needed, and future research in this area
should probably differentiate early-onset
and regressed subsets.
Absent antibody response to prior
vaccination is reported by many
clinicians. One study documented absent
antibody to rubella in 5 of 13 previously
vaccinated autistic children, versus no
such absence in the control group.10 Both
T cells and B cells contribute to generation of antibodies after vaccination. Numbers and function of CD4+ T cells are in
question in autism, and it is the CD4+
cell that activates B cell production of
antibodies to vaccines.4 A summary is
shown in T1.
A Pattern of Inflammatory
Activation in Autism
In autism, there is clear-cut evidence
of activation of the immune response
system, which may be due to innate,
toxic, or infectious influences - or some
combination of these factors. Viral infection may underlie the immune activation.
Alpha-interferon, a cytokine from monocytes, acts on cells throughout the body
to inhibit viral replication, so elevations
are consistent with response to viral infection. Alpha interferon is elevated in
autism (P<.001), and as an extremely
potent analgesic that produces marked
social withdrawal and speech loss in
large doses when used as treatment for
cancer, it may also explain the character-
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(Hib), often given in combination with
HepB and/or diphtheria-pertussis-tetanus
(DPT). Due to recent safety concerns,
thimerosal-free alternatives for each of
these vaccines have become available.
No thimerosal-free version of the
influenza vaccine, often recommended
for children, is yet available.
We postulate that thimerosal in vaccines may cause direct neurotoxic, immunodepressive, and autoimmune injury
resulting in either early-onset or
regressed autism. Further, we submit that
MMR (usually at 15 months) may result
in chronic infection of the gut by
vaccinial measles, and trigger regressed
autism. Thimerosal injections in series
prior to or at the time of MMR may potentiate injury by MMR.
Chronic measles infection from
MMR is suggested by studies that demonstrate: 1) chronic vaccinial measles infection of the peripheral monocytes of
autistic children with enterocolitis; 2) genomic material consistent with chronic
measles infection in intestinal biopsies of
regressed autistic children with enterocolitis; and 3) presence in the majority of
autistic children of a unique anti-MMR
antibody highly correlated with a marker
for nervous system autoimmunity.
Autoimmune injury to both gut and brain
is suggested in autism.
An injured, inflamed gut emerges
from the current literature as a dominant
theme in autism, and both thimerosal and
MMR may be contributors. An integrated
approach to autism considers the nutritional and toxic implications of gut dysfunction. Many autistic children
demonstrate low nutrients and elevated
urinary peptides and organic acids with
toxic properties. The field of clinical
pathology will continue to provide crucial
data in understanding autism and the possible role of vaccines, as well as perhaps
develop criteria for the deferral of
vaccines in certain children at risk.
709
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T1
Immune Impairment in Groups of Mixed Regressed and
Early-Onset Children With Autism
Immune Element
Finding in Autism
Reference
T lymphocytes
Low CD4+ counts 28%
Poor response to mitogen P<.001
(4)
(2)
B lymphocytes
Low CD20+ counts 48%
Low IgA 20% / low IgG sub 20%
(4)
(4,6) / (1)
NK cells
Low cytotoxic function 40%
(8)
C4A null allele
58% versus 27% controls
(9)
Negative postvaccination titers
38% versus 0% controls
(10)
Inflammatory Activation in Groups of Mixed Regressed and
Early-Onset Children With Autism
Finding in Autism
Reference
Higher interferon alpha
P<.001
(11)
Higher interferon gamma
P<.05; <.02
(12,13)
Elevated neopterin
[urine] x 10 control
(14)
Elevated interleukins
High IL-2 / IL-12 x 20
(13,15)
istic social withdrawal, communication
deficit, and high pain threshold in autistic
children.11 Higher IL-1RA, also from
monocytes, is reported in autism (P <.01)
and may also reflect monocytic response
to viral infection.12
Gamma-interferon, a pro-inflammatory cytokine from T-helper 1 CD4+ lymphocytes, exerts strong antiviral influences
via multiple mechanisms, favors IgG production by B cells, and helps activate cytotoxic cells. Gamma-interferon is
elevated in autistic children compared
with matched controls in 2 studies (P<.05
and P<.02).12,13 Neopterin levels are clinically useful markers for activation of cellular immunity in a broad range of
illnesses. Urinary neopterin levels are 10
times greater in autistic children, likely
reflecting higher gamma-interferon.14
Interleukins (ILs), a class of proinflammatory cytokines, are selectively
elevated in autism. Interleukin-2, produced mostly by T helper 1 cells, is a
primary marker for immune activation,
and is higher in children with autism.15
Interleukin-12, released from T cells, B
cells, NK cells, and monocytes, stimulates cytotoxic cells and promotes differ-
entiation toward T-helper 1 cells. Interleukin-12 is also elevated in children
with autism.15
Lagging NK-cell numbers and function and the elevation of 3 primary activators of NK cells (interferon gamma,
IL-12, and IL-2) may reflect a key problem such as chronic viral infection in
autism. Interferon gamma increases NK
adherence and lytic capability; IL-2
stimulates greater numbers of NK cells
and increases lysis; and IL-12 is the
most potent NK-cell activator of all.16 A
summary is shown in T2.
A Pattern of Autoimmunity in
Autism
Markers for autoimmunity are predominate in autism, and autoimmunity is
one of the conditions associated with activation of the inflammatory response. Occurrence of autoimmune illness is 8 times
higher in mothers of autistic children.17
Major histocompatibility class (MHC)
proteins are important modulators of the
immune response, and in animals MHC
subtype determines susceptibility to autoimmune response to antigens such as
mercury.18 Major histocompatibility class
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710
Inflammatory Marker
T2
haplotype B44-SC30-DR4 is grossly overrepresented in recognized autoimmune
disorders such as rheumatoid arthritis. The
incidence of this specific haplotype is
40% in autistic children or their mothers,
versus 2% of a control group.19
Antibodies to central nervous system
antigens are common in autism. One
study finds 58% of autistic children positive for antibody to myelin basic protein
(MBP), versus only 8% in a mixed comparison group comprised of normal and
mentally retarded and Down syndrome
children.20 Another study demonstrates
nearly 70% of autistic children positive
for anti-MBP.21 Markedly higher levels of
autoantibody to neurofilament protein
(NFP) and glial fibrillary acidic protein
(GFAP) are found in autistic children
compared with normal subjects and subjects who are mentally retarded, with antiNFP in 55% and anti-GFAP in 32% of the
autistic group.22 Serum levels of brainbinding antibodies to nuclear antigen and
brain endothelium are higher in autistic
children, including IgM autoantibodies in
36%.23 Macrophage migration inhibition
by MBP, implicated in the pathophysiology of other neurological disorders, is
demonstrated in 77% of autistic children
but none of a control group.24
Macrophage dysregulation is inherent
in autoimmune disease. Interleukin-12
from macrophages selectively induces
interferon gamma in T helper 1 cells. Elevated IL-12 and interferon gamma in
autism are consistent with an active autoimmune process. Interleukin-12 is
known to initiate organ-specific autoimmunity by activation of T Helper 1 cells.21
Interferon gamma, in turn, activates IL-12
and appears to be the primary stimulus for
autoantibody production in response to
mercury.25 An interferon gamma/IL-12/T
helper 1 mechanism is suggested for autoimmune reactivity to measles as well.21
Normal values of T helper-2 cytokines IL4, IL-5, and IL-6 in autism12 are not inconsistent with this mechanism for
autoimmune activation in autism.
Recent evidence suggests that an autoimmune lesion exists in the autistic gut.
Complement C1q and IgG deposition in
the basolateral epithelium and basement
membrane in the duodenum of 23 of 25
왗your lab focus 왘
autistic children referred for gastrointestinal symptoms was also associated with
increased epithelial infiltration by CD8+
lymphocytes.26 Complement and IgG deposition was not seen in controls. A summary of autoimmunity is given in T3.
Mercurials27,28 and infectious
agents12,29 may trigger autoimmune disease. As a source of both mercury (Rhimmunoglobulin, DTaP, HepB, Hib,
influenza) and live virus (MMR), vaccines
may play independent or combined roles
in the physical illness underlying autism.
Many parents report onset of autistic
symptoms in their children shortly after 1
or more of these vaccines.21
Autoimmune Marker
Finding in Autism
Reference
Familial tendency autoimmune disease
Mothers x 8
(17,19)
Elevated anti-MBP
58% / 70%
(20,21)
Elevated anti NFP / GFAP
55% / 32%
(22)
Elevated Ab to brain nucleus and endothelium
IgM 36%
(23)
Macrophage migration inhibition by MBP`
77% versus 0% controls (24)
Elevated interferon gamma
P<.05; <.02
(12,13)
Elevated IL-12
x 20 controls
(13)
Duodenal IgG / complement / CD8+ infiltration*
92% versus 0% controls (26)
*This group included only regressed autistic children with GI symptoms.
Case Study: Autistic Child C.M. DOB 12-1-94
Age Vaccinated
Vaccine(s)
Parenteral Mercury Dosage
2 weeks
Hep-B
12.5 µg Hg as
Thimerosal
2 months
Hep-B, DTaP, Hib
12.5, 25, 25 µg Hg
4 months
DTaP, Hib
25, 25 µg Hg
6 months
H-B, DTaP, Hib
12.5, 25, 25 µg Hg
15 months
MMR
Live vaccine,
no Thimerosal
18 months
DTaP
25 µg Hg
T4
*Patient of author.
Mercury exposure from vaccines is
surprisingly high. General concern about
thimerosal in vaccines was stimulated by
the relatively recent realization that infants
receiving these vaccines were getting
bolus amounts of injected organic mercury
which, even averaged over time, could exceed the Environmental Protection Agency
(EPA) concern level for total average mercury exposure from all sources. A trend
towards earlier and higher dosing of injected thimerosal with the successive introduction of new vaccines has reversed only
in the past 2 years, as many physicians and
medical institutions shift to thimerosal-free
alternative vaccines.
Autistic histories are often positive
for high thimerosal doses. T4 shows the
vaccination schedule of a regressed
autistic child with normal development
until 18 to 20 months, then loss of
©
speech, eye contact, social interaction,
and attentiveness.
The EPA concern level for total mercury exposure from all sources (0.1
m g/kg/day) is for ongoing exposure from
all sources, and did not specifically consider large injected boluses of mercury.
Application of the criterion to vaccines is
therefore disputed. Some experts suggest
that exposure calculations for mercury
from thimerosal injection should be averaged over time, while others contend that
looking at single-day exposure is more
accurate because it is less likely to underestimate heightened risk from episodic
large boluses.
Child C.M. exceeded the concern
level by either calculation. Over the first
6 months, assuming a generous average
weight of 7 kg, concern level would be
126 m g total Hg exposure from all
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The Case Against Vaccines
Containing Thimerosal
As a class, organic mercurials are
renowned for neurotoxic effects at very
low doses, and sensitivity to mercurials
is highly variable. Thimerosal, a form
of ethylmercury, is also called "merthiolate." Topical merthiolate in infants
with omphalocele30 and merthiolate ear
irrigations31 have resulted in significant
toxicity. Methylmercury and thimerosal
are very similar chemically, but more
health data are available for methylmercury. The National Academy of
Sciences stated that methylmercury exposure alone may cause neurological
problems in an estimated 60,000 children born in the United States every
year.32 Studies in animals and human
subjects demonstrate that thimerosal is
taken up by the brain.33 Over many
decades the safety of thimerosal in humans has not been studied thoroughly.
T cells are particularly sensitive to
methylmercury, and both T-cell and NKcell activity significantly decrease with
chronic exposure.28 Depressed antibody
production is seen in experimental organic mercury exposure.28 Antibodies to
central nervous system proteins are common in human and experimental
methylmercury exposure, and imply one
of many mechanisms for neurotoxicity.27
Allergenicity of certain contact lens solutions containing thimerosal is also
known. In vitro studies suggest potent
toxicity of thimerosal at cellular and enzyme levels.33,34
T3
Autoimmunity in Groups of Mixed Regressed and Early-Onset
Children with Autism
711
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(PDE),48 while mercurials are renowned
for L-channel blockade and PDE inhibition. Mercury inhibits the rod light
response by inhibiting PDE,49 and poor
rod light response is demonstrated in half
of autistic children on
electroretinograms.50
A large unpublished governmentsponsored thimerosal study is not comforting. The study considered correlation
between diagnoses on HMO charts and
total thimerosal received during infancy.
Initial screening analysis of more than
110,000 charts revealed correlations between amount of thimerosal injected in the
first 6 months and problems reminiscent of
autism, but not autism per se: speech delay
P<.0001,·neurodevelopmental disorder
P<.01, and attention deficit P<.06.
There is no question the initial large
screening study suggested a problem with
thimerosal. At the time these data were
presented, the lead investigator asserted "a
possible association between certain neurological disorders and exposure to mercury from thimerosal-containing vaccines
before the age of 6 months."51 A year
later, after inclusion of more charts from a
second HMO and various statistical and
methodological treatments, government
agencies made reassuring
pronouncements about no link between
autism and thimerosal. We contend that
the study may have provided an initial
glimpse of a problem, but otherwise
should be discounted, owing to a flawed
methodology which renders it as a nonsensitive method.
Sickly infants (premature infants, infants with more serious illness, infants
requiring longer hospitalizations) were
excluded from this toxicological assessment. This exclusion criterion overlooks
the likelihood that physically weaker subjects are more sensitive to the injurious
effects of toxins. More specifically, exclusion of children with certain pathologies
may overlook the very mechanisms inherent to toxicity. For example, exclusion of
infants with neonatal jaundice (bilirubin
>16mg/dL in 13% of autistic children vs
3% in controls)52 would effectively
remove a subgroup arguably most prone
to problems with organic mercury excretion, which in all humans studied is pri-
©
marily biliary-fecal. Sickly infants with
immunodeficiency were undoubtedly excluded from the study, yet mercury itself
is a strong immunosuppressant, etc.
Minds are still open on this subject.
After hearings, the Institute of Medicine
acknowledged in the summer of 2001
that a link between vaccinial thimerosal
and autism is "biologically plausible.”34
In the autumn of 2001, The National Institute for Environmental Health Safety
(NIEHS) committed major university
funding to investigate the role of mercury
in autism. The FDA has discouraged the
production of thimerosal-containing
scheduled childhood vaccines but has not
withdrawn existing stocks of such vaccines from the market.
The Case against MMR: Chronic
Infection and Autoimmunity
The manufacturer of MMR vaccine
specifies the following contraindications
in the 2002 Physician's Desk Reference:
primary and acquired immunodeficiency
states, or cellular immune deficiencies, or
hypogammaglobulinemic states
Measles infection from live virus in
MMR is a real possibility in the immunosuppressed host, sometimes in unusual
locations. For instance, necrotizing
measles lymphadenitis after vaccination
was reported in a child with familial cellular immunodeficiency.53 We hypothesize
increased risk of chronic measles infection
complicating MMR in a subgroup of children with common variable immunodeficiency or selective deficits, particularly if
these immune deficits are superimposed
on subclinical nutritional deficiencies or
other vulnerabilities. Recognition of such
a vaccine-injured subset of children would
be more difficult if the infection is latent,
or in the case of a neurobehavioral syndrome such as autism, outside the brain.
A spectrum of recognized adverse reactions to vaccines is associated with immune deficits. Low titers of specific
antibodies to tetanus toxoid are found in
80% of a subgroup of children with abnormal reaction to measles vaccination,54
which parallels the previously-described
negative rubella titers in vaccinated autistic
children. The same study demonstrates that
reactions to another live vaccine, oral polio,
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sources, versus 182.5 m g from
thimerosal injection alone. Conversely,
applying the EPA concern level on a
daily basis would be even more worrisome - at 2 months of age if the child
weighed 5 kg, the single-day concern
level for the day of the vaccinations
would be 0.5 m g, versus actual injection
of 62.5 m g of mercury as thimerosal.
There exist striking similarities between autism and mercury poisoning, a
full listing of which36,37 falls outside the
scope of this article. One of the more
compelling comparisons is a historic illness dubbed Pink Disease (acrodynia),
which resulted from mercurial teething
powders, lotions, and diaper powders
eliminated from usage by the 1950s. In
its behavioral aspect, Pink Disease was
similar to autism.37
Corresponding changes in the appearance of intestinal Paneth cells38 are seen in
experimental methyl mercury exposure39
and biopsies from autistic children.40 Mercury may interfere with Paneth cell release
of defensins for local immunity to infection
from viruses, bacteria, and yeast.
The profile of immune depression in
mercury exposure parallels specific abnormalities in many autistic children. T-cell
and NK-cell activity significantly decrease
with chronic methylmercury exposure.28
Depressed antibody production is seen in
experimental organic mercury exposure.28
Mercury exposure produces the same
set of nervous system autoantibodies seen
in autism. Experimental animal exposure
and human industrial exposure to mercury
produces levels of anti-MBP, anti-NF, and
anti-GFAP which correlate with exposure
level and degree of clinical symptoms in
mercury poisoning.27 A relatively new
immunoassay, Memory Lymphocyte Immunosensitivity Assay (MELISA by
copyright) measures the reactivity of hapten-specific lymphocytes to various allergens, including heavy metals.41-45 Allergic
reactivity to metals measured by MELISA
varies markedly among individuals and is
specific for different forms of mercury.46
Parathyroid hypertensive factor
(PHF) is a circulating hormone measurable in the blood. Parathyroid hypertensive
factor is known to open calcium L-channels47 and stimulate phosphodiesterase
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714
Suggestion of Chronic Vaccinial
Measles Infection from MMR
Chronic vaccinial measles infection
of mononuclear cells is suggested by 1
published study. Measles RNA was
found in the peripheral mononuclear
cells in 3/9 regressed autistic children
with enterocolitis. Differentiation of
wild virus from vaccinial virus was not
definitive, but presumptive wild measles
RNA from 1/8 patients with Crohn's
Disease, presumptive vaccinial measles
from 1/3 ulcerative colitis patients, and
presumptive vaccinial measles RNA
from all 3 of the autistic children were
consistent with exposure history.59
Small intestinal measles infection has
been found in autism. Reverse transcription polymerase chain reaction found
measles RNA in distal ileal biopsies of
75/91 (87%) of regressed autistic children
with ileal lymphoid hyperplasia versus
5/70 controls (7%). The measles RNA
was primarily localized in dendritic cells
and lymphocytes in reactive follicular hyperplastic centers.60 The study does not
distinguish vaccinial from wild measles
virus. It does pose a most insistent question about the role of MMR.
One study presents serological
evidence pointing to vaccinial measles from
MMR. An unusual antibody to MMR was
found in 75/125 (60%) of autistic children
not selected for regression, versus none of
92 controls. Monoclonal antibody studies
strongly suggest that this unusual MMR
antibody is related only to the measles component of the MMR vacine, not other contents of the MMR vaccine. Greater than
90% of the sera with the unusual MMR
antibody are positive for anti-MBP, suggesting a causal relationship between MMR
vaccination and autoimmunity in autism,
conceivably related to atypical measles infection.61 In the same study, autistic children were found to have significantly
higher (P<.001) than normal levels of antibody to both measles virus and MMR antibodies, but not to separate mumps or
rubella. Viral infections do induce autoantibodies during the course of infection.62
Measles virus protein and human intermediate filament protein are antigenically cross-reactive in monoclonal
antibody studies, and subjects with wild
measles infection are known to generate
antibody to cytoskeletal intermediate filaments.62 Neurofilament and glial filament
in the brain are intermediate filament proteins, as is keratin, which stabilizes gut
epithelial cells. Viral-effected molecular
mimicry offers a possible explanation for
antibody to nervous system.21 In autism,
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©
MHC DR3+ lymphocyte expression is
elevated.63,64 Elevated MHC DR+ activated lymphocytes in autism increase
brain permeability to autoantibody by interacting with MHC class 1 expression.22
Organic mercurials are also known to permeate the blood-brain barrier.28
Characteristics of wild measles infection increase MMR doubts. Direct infection of the brain by wild measles virus
occurs 1 to 7 months after acute measles
and is characterized as measles inclusion
body encephalitis (MIBE). Measles inclusion body encephalitis in an apparently
healthy child after MMR was confirmed
secondary to vaccinial measles virus.65
MMR-induced subacute sclerosing panencephalitis is well-documented.66,67 Wild
measles delayed encephalopathy without
evidence of direct viral invasion of the
brain but with clinical features of demyelination is associated with a lymphocytic
proliferative response to MBP in over half
the affected children, many of whom suffer
long-standing neurological deficits ranging
from behavioral abnormalities to seizures
to persistent motor deficits.68 It is unclear
whether any of these children satisfied the
diagnosis of autism.
View of Vaccines From a
Broader Perspective on Autism
We do not suspect thimerosal and
MMR to be the only triggers for autism.
In our clinical experience, nutritional status, food intolerances, concomitant infections and other toxic influences
appreciably affect the symptoms of
autism, and we think these same factors
may potentiate vaccine insult.
Suboptimal nutritional status is
demonstrated in most autistic children
when sensitive measurements are used.
Scores of physicians are finding low intracellular or functional measurements of
nutrients such as zinc, magnesium, vitamin B6, and fatty acids in the majority of
autistic children, and report excellent improvement with supplementation of these
nutrients. This clinical observation needs
confirmation with large studies using
well-matched controls.
Vitamin A, dubbed the "anti-infective" vitamin in the pre-antibiotic era, definitely trends lower in autism and is of
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were associated with low numbers of T
lymphocytes as assessed by E-rosette formation in 50% of a subgroup of children.
Identical methodology demonstrated decreased T cells in autism as well.2 Again,
the same study demonstrates low IgA levels 5 times more commonly in children
with severe reactions to DPT than in a
comparison group of children being evaluated for clinical suspicion of immune deficiency (17% vs 3.3%), also of interest in
the context of lower IgA levels in autism.54
Either the poor immunity seen in
children with more severe recognized reactions to vaccines is an antecedent
marker for such reactions, or immune impairment follows vaccination. Neither possibility is comforting when we know that
immune impairment of autistic children
exists after vaccination.
After several years of investigation,
we now understand that the autistic gut is
extensively inflamed. Reflux esophagitis
(69%), chronic gastritis (42%), and
chronic duodenitis (67%) are found in the
subgroup of autistic children with
gastrointestinal symptoms, irritability, or
sleeplessness.40
Enterocolitis with lymphonodular
hyperplasia (LNH) is common in postMMR regressions. Initial colonoscopic
evaluation of a small group of regressed
children with gastrointestinal symptoms
revealed ileal LNH in 7/12, and patchy
chronic colitis in 11/12 autistic children.55
Subsequent study of a larger group with
regression and bowel symptoms found
ileal LNH in 89% and colitis in 88%.56
Some experts are of the opinion
that the ileal LNH and nonspecific enterocolitis found in the regressed autistic
group are not classical inflammatory
bowel disease.57 The histology of children regressed after MMR may be sufficiently distinctive to warrant the label,
"autistic enterocolitis."58
왗your lab focus 왘
tack.75 Mercurial compounds have a direct, potent inflammatory effect on the
gut,38 and vaccinial infection of gut tissue
may be highly injurious. The precise interplay and predominance of these factors
is not yet defined.
Studies suggest intestinal protein
loss81 and malabsorption in many autistic children.82 Secretin, produced by the
intestinal brush-border, is important in
digestion and support of the bowel
membranes, and perhaps also at binding
sites within the brain. Circulating
secretin levels are often measurably low
in autism, at least against an adult reference range.83 Other deficient products
of the brush border include the disaccharidases (lactase, sucrase, or maltase),
low in 58% of autistic children with
gastrointestinal complaints.40
Inadequate digestion of disaccharides
may favor overgrowth of detrimental
flora in the autistic gut.
Increased intestinal permeability
(leaky gut) is suspected in the majority of
autistic children, and is even found in 43%
of the subgroup of autistic children without
overt signs or symptoms of gut disease,
versus 0/40 controls.84 A leaky autistic gut
is the suspected vehicle for multiple pathological mechanisms in autism. Very high
urinary levels of toxic organic acids from
fungal and anaerobic organisms are found
in autistic children, and these are probably
absorbed from the gut.85 Peptides from
inadequate digestion of casein and gluten
apparently are absorbed in excess by autistic children, as reflected by very high levels
of urinary peptides.86,87 Poor peptidase production may combine with leaky gut to
produce the marked elevation of urinary
peptides.
Excessive peptides from undigested
casein and gluten are suspected to exert
significant toxicity. Large numbers of parents and clinicians88 report improvement of
autistic children on gluten- and casein-free
diets, the full benefit of which may not be
evident for many months of dietary exclusion. Peptides from undigested casein and
gluten are known to have potent opioid activity,89-91 and opioid peptides can adversely
effect brain development.92,93
In the context of thimerosal, it should
be noted that the converting enzyme for
©
casein and gluten, Dipeptidyl Peptidase
IV (DPPIV), is inhibited by mercury at
very low concentrations.94 Similarly, mercury in nanomolar concentrations totally
inhibits the intestinal pyridoxal kinase,95
activator of Vitamin B6, which has been
found to benefit children with autism in
18 published studies.96
The answers in autism will derive
from an integrated approach, which considers the definitively close relationships
of brain, immunity, gut, and environmental influences such as nutrition, toxins,
and infectious agents. A particularly intriguing discussion currently centers on
CD26, which epitomizes the closeness of
seemingly disparate systems. CD26 is a THelper 1 marker, a T-cell activation antigen that acts as the co-stimulatory
activation molecule on memory CD4+
cells and controls many aspects of lymphocyte function, presumably including
modulation of the response to vaccines.
Interferon, IL-12, and vitamin A all tend
to upregulate CD26 gene expression.
CD26 is a receptor for adenosine deaminase, low levels of which are associated
with impaired cellular immunity.97 Adenosine deaminase is decreased in autism.98
CD26 is very interesting from the immune
perspective, but truly exciting with an additional realization: CD26 and enzyme
DPPIV (gluten/casein digestion) are one
and the same.99 As a key element in both
the immune and digestive systems, with
seeming pertinence to neurobehavior, this
molecule can model the unified thinking
we need in autism.
Conclusion
Depressed immunity, autoimmunity,
and inflammatory activation are common
features in autism. Impaired resistance to
infection may predispose to chronic
measles infection of the autistic gut by
MMR vaccine. Thimerosal-containing
vaccine during infancy may depress immunity and lower the threshold for
chronic vaccinial measles infection.
Thimerosal and MMR may induce
autoimmunity to elements of the CNS
individually or additively and thus contribute to the pathophysiology of autism.
Significant anatomic and functional
gut abnormality is a prevailing theme in
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particular interest in the context of suspected chronic measles infection of the
gut after MMR. Vitamin A is critically
important in resistance to measles infection, membrane protection, and vision.
High doses of vitamin A are indicated
treatment for severe measles, and low
serum vitamin A measurements correlate
directly with severity of illness from
measles.69 Both vitamin A70,71 and IgA
levels72 are depressed in wild measles
infection. One pilot study found low vitamin A levels in 40/65 autistic
children,73 attesting to an earlier
published claim of low or borderline
serum retinol levels in autism.74 This is
plausible because generally, young children are suspected to have widespread
subclinical vitamin A deficiency.75
Visual problems in autism such as
lateral gaze,76 poor depth perception, and
poor facial recognition may reflect poor
rod function related to vitamin A. Most
mothers of autistic children have mild to
severe night vision deficits,74 and as discussed previously in the context of elevated PHF in autism, many autistic
children are known to have abnormal
retinograms consistent with rod dysfunction.50 Abnormal rod function on retinogram post-MMR is reported in a child
with selective CD4+ deficiency.77
Zinc is especially important in cellmediated immunity. Low NK-cell
activity,78 low CD4+ counts, and anergy
to skin-testing79 improve significantly
with zinc supplementation of non-autistic
children. Brush border enzyme activity
and secretory antibodies improve with
zinc supplementation,80 as does diarrheal
disease, which is known to accelerate zinc
loss.75 Intracellular assay suggests zinc
deficiency in at least half of the autistic
children.73 Administration of zinc to autistic children with low intracellular or lower
plasma zinc levels often provides dramatic
improvement in bowel and behavior.
A gut weakened by nutritional factors
is potentially more prone to injury by vaccines. Zinc deficiency, vitamin A
deficiency, and immunoglobulin-mediated
food intolerances are recognized causes of
gastrointestinal inflammation. Even mild
depletion of vitamin A reduces protective
mucus and predisposes to microbial at-
715
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independent thinking may be the only way
to resolve certain institutional contradictions, as in the conflicting recommendations pertaining to administration of MMR
to children with febrile illness.67 As many
of our colleagues have already determined,
the respect for our vaccination program is
not lessened if the physician decides to
wait a reasonable period after diarrhea or
other illness has abated, or advise cod liver
oil prophylaxis before vaccination.99
Published science and clinical experience are converging rapidly to form a
more accurate image of autism. We are
learning that autism implies a physically
ill child with associated immune, gut, and
nutritional problems. Besides helping target biological interventions for autism,
understanding the underlying physical
problems enhances our grasp of the possible role of vaccines.
1. Yonk LJ, Warren RP, Burger RA, et al. CD4+
helper T cell depression in autism. Immunol Lett
1990;25:341-346.
2. Warren RP, Foster A, Margaretten C, et al.
Immune abnormalities in patients with autism. J
Autism Develop Dis 1986;16:189-197.
3. Warren RP, Yonk LJ, Burger RA, et al. Deficiency
of suppressor-inducer (CD4+CD45RA+) T cells in
autism. Immunol Invest. 1990;19:245-251.
4. Gupta S, Aggarwal S, Heads C. Dysregulated immune
system in children with autism: beneficial effects of
intravenous immune globulin on autistic
characteristics. J Autism Devel Dis. 1996;26:439-452.
5. Stubbs EG, Crawford ML. Depressed lymphocyte
responsiveness in autistic children. J Autism Child
Schizophr. 1977;7:49-55.
6. Warren RP, Odell JD, Warren WL, et al.
Immunoglobulin A deficiency in a subset of
autistic subjects. J Autism Develop Dis.
1997;27:187-192.
7. Fiumara A, Sciotto A, Barone R. Peripheral
lymphocyte subsets and other immune aspects in
Rett syndrome. Pediatr Neurol. 1999;21:619-621.
8. Warren RP, Foster A, Margaretten NC. Reduced
natural killer cell activity in autism. J Am Acad
Chld Adolesc Psych. 1987;26:333-335.
9. Warren RP, Singh VK, Cole P. Increased
frequency of the null allele at the complement
C4b locus in autism. Clin Exp Immunol.
1991;83:438-440.
10. Stubbs EG. Autistic children exhibit undetectable
hemagglutination-inhibition antibody titers despite
previous rubella vaccination. J Autism and Child
Schizophr. 1976;6:269-274.
11. Stubbs EG. Interferonemia and autism. J Autism
Develop Dis. 1995;25:71-73.
12. Croonenberghs J, Bosmans E, Deboutte D, et al.
Activation of the inflammatory response system in
autism. Neuropsychobiology. 2002;45:1-6.
13. Singh VK. Plasma increase of interleukin-12 and
interferon-gamma: pathological significance in
autism. J Neuroimmunol. 1996;66:143-145.
14. Messahel S, Pheasant AE, Pall H, et al. Urinary
levels of neopterin and biopterin in autism.
Neurosci Lett. 1998:241:17-20.
laboratorymedicine> september 2002> number 9> volume 33
©
15. Singh VJ, Warren RP, Odell JD, et al. Changes of
soluble interleukin-2, interleukin-2 receptor, T8
antigen, and interleukin-1 in the serum of autistic
children. Clin Immunol Immunopath.
1991;61:448-455.
16. Peakman M, Verani D. Basic and clinical
immunology. New York, NY: Churchill
Livingston; 1997:108.
17. Comi AM, Zimmerman AW, Frye VH, et al.
Familial clustering of autoimmune disorders and
evaluation of medical risk factors in autism. J
Child Neurol. 1999;14:388-394.
18. Kono DH, Park MS, Szydlik A, et al. Resistance
to xenobiotic-induced autoimmunity maps to
chromosome 1. J Immunol. 2001;167:2396-2403.
19. Daniels WP, Warren RP, Odell JD, et al. Increased
frequency of the extended or ancestral haplotype
B44-SC30-DR4 in autism. Neuropsychobiol.
1995;32:120-123.
20. Singh VK, Warren RP, Odell JD, et al. Antibodies
to myelin basic protein in children with autistic
behavior. Brain Behav Immun. 1993;7:97-103.
21. Singh VK, Lin SX, Yang VC. Serological
association of measles virus and human herpes
virus-6 with brain autoantibodies in autism. Clin
Immunol Immunopathol. 1998;89:105-108.
22. Singh VK, Warren R, Averett R, et al. Circulating
autoantibodies to neuronal and glial filament
proteins in autism. Pediatr Neurol. 1997;17:88-90.
23. Connolly AM, Chez MG, Pestronk A, et al. Serum
autoantibodies to brain in Laundau-Kleffner
variant, autism, and other neurological disorders. J
Peds. 1999;134:607-613.
24. Weizman A, Weizman R, Szekely GA, et al.
Abnormal immune response to brain tissue
antigen in the syndrome of autism. Am J Psychiat.
1982;139:1462-1465.
25. Kono DW, Balomenos D, Pearson DL, et al. The
prototypic Th2 autoimmunity induced by mercury
is dependent on IFN-Gamma and not Th1/Th2
imbalance. J Immunol. 1998;161:234-240.
26. Torrente F, Ashwood P, Day R, et al. Small
intestinal enteropathy with epithelial IgG and
complement deposition in children with regressive
autism. Molec Psych. 2002;7:375-382.
27. El-Fawal H, Waterman SJ, De Feo A, et al.
Neuroimmunotoxicology: humoral assessment of
neurotoxicity and autoimmune mechanisms.
Environ Hlth Persp. 1999;107:767-775.
28. Chang KW ed. Toxicology of Metals. Boca Raton,
FL: CRC Press; 1996:842-845.
29. Wucherpfennig KW. Mechanisms for the
induction of autoimmunity by infectious agents. J
Clin Invest. 2001;108:1097-1104.
30. Fagan DG, Pritchard JS, Clarkson TW, et al.
Organ mercury levels in infants with
omphaloceles treated with organic mercurial
antiseptic. Arch Dis Child. 1977;52:962-964.
31. Rohyans J, Walson PD, Wood GA. Mercury
toxicity following merthiolate ear irrigations. J
Pediatr. 1984;104:311-313.
32. National Academy of Sciences press release, July
21, 2000.
33. van der Laan JW, de Waal E. Safety working party
assessment of the toxicity of thimerosal in relation
to its use in medicinal products. The European
Agency for the Evaluation of Medicinal Products;
London: 8 September 1998: B04210.
34. Stratton K, Gable A, McCormick MC, eds.
Immunization safety review: thimerosal-containing
vaccines and neurodevelopmental disorders.
Immunization safety review committee, board on
health promotion and disease prevention, the Institute
of Medicine. 2001 Available at:
www.iom.edu/imsafety. Accessed on August 7, 2002.
35. TEST Foundation. Available at:
www.altcorp.com/testfoundation.htm Accessed on
August 7, 2002.
Downloaded from http://labmed.oxfordjournals.org/ by guest on April 12, 2016
716
autism, and may be aggravated by injury
from MMR and thimerosal or predispose
to such injury. Much of the clinical
knowledge about nutritional aspects of
autism, such as low zinc and vitamin A
status, help explain a weakened autistic
immunity and gut as well as vulnerability to vaccine injury. Ingress of toxins
from the gut reflects gut injury and appears significant.
We are far from certain that vaccines
help trigger autism, but we are farther still
from certain they do not. Given current
available data, thimerosal would stand no
chance of approval as a new injectable
medication by modern standards, and because thimerosal alternatives exist for all
the scheduled childhood vaccines, we call
for its summary removal and safe disposal
from every repository in this country. We
also encourage an intensive effort to find
economical thimerosal-free childhood
vaccines for the rest of the world.
In many respects, the autistic immune
profile fits the diagnostic category of common variable immunodeficiency (CVID).
Common variable immunodeficiency is
strongly associated with gastrointestinal
disease, including LNH, in multiple studies.100-103 Autism may very well be nature's
way of demonstrating a subgroup of CVID
children vulnerable to vaccine injury. Current official vaccination guidelines do not
exclude CVID children from usual vaccination, but we think this needs refinement.
We call for well-funded prospective studies
by individuals without conflicts of interest
to determine immune, autoimmune, gastrointestinal, and long-term neurobehavioral effects of vaccination, particularly in
relation to immune, gut, and nutritional
status before and after vaccination. Development of screening tests to identify children with higher risks of any negative
effects of MMR should be a high priority.
Such screening might include skin-testing
for anergy, dietary; family questionnaires to
identify possible low vitamin A levels;
tetanus titers for anergy; or immunoglobulin and T-cell counts in special cases.
In this period of major uncertainty
over MMR and autism, the thoughtful
physician would be counseled to temper
existing institutional and corporate vaccine
guidelines with clinical judgment. In fact,
왗your lab focus 쐽
59. Kawashima H, Mori T, Kashiwagi Y, et al.
Detection and sequencing of measles virus from
peripheral mononuclear cells from patients with
inflammatory bowel disease and autism. Digest
Dis Sci. 2000;45:723-729.
60. Uhlmann V, Martin CM, Sheils O, et al. Potential
viral pathogenic mechanism for new variant
inflammatory bowel disease. J Clin Pathol Mol
Pathol. 2002;55:1-6.
61. Singh VK. Abnormal measles serology and
autoimmunity in autistic children. J Allergy Clin
Immunol. 2002;109:S232.
62. Fujinami RS, Oldstone MB, Wroblewska Z, et al.
Molecular mimicry in virus infection:
Crossreaction of measles virus phosphoprotein or
of herpes simplex virus protein with human
intermediate filaments. Proc Nat Acad Sci USA.
1983;80:2346-2350.
63. Warren RP, Odell JD, Warren WL, et al. Strong
association of the third hypervariable region of
HLA-DR Beta-1 with autism. J Neuroimmunol.
1996;67:97-102.
64. Plioplys AV, Greaves A, Kazemi K, et al.
Lymphocyte function in autism and Rett's
syndrome. Neuropsychobiol. 1994;7:12-16.
65. Bitnun A, Shannon P, Durward A, et al. Measles
inclusion-body encephalitis caused by the vaccine
strain of measles virus. Clin Infec Dis.
1999;29:855-861.
66. Belgamwar RB, Prasad S, Appaya P. Measles,
mumps, rubella vaccine induced subacute
sclerosing panencephalitis. J Indian Med Assoc.
1997;95:594.
67. Physician's Desk Reference 2002. Montvale NJ:
Medical Economics Company; 2002:2120.
68. Johnson RT, Griffin DE, Hirsch RL, et al. Measles
encephalomyelitis- clinical and immunologic
studies. N Engl J Med. 1984;310:137-141.
69. Caballero B, Rice A. Low serum retinol is associated
with increased severity of measles in New York City
children. Nutr Rev. 1992;50:191-192.
70. Yalcin SS, Yurdakok K, Ozalp I, et al. The effect
of live measles vaccines on serum vitamin A
levels in healthy children. Acta Paediatr Jpn.
1998:40:345-349.
71. Butler JC, Havens PL, Sowell AL, et al. Measles
severity and serum retinol (vitamin A)
concentration among children in the United States.
Pediatrics. 1993;91:1176-1181.
72. Gupta PC, Dutta AK, Khare S, et al.
Immunoglobulins profile of measles. Indian
Pediatr. 1989;26:780-784.
73. Audhya T. Abnormalities and dysfunction of
vitamins and fatty acids in autism. Defeat Autism
Now Symposium, Phoenix, AZ, July 2000.
74. Megson MN. Is autism a G-alpha protein defect
reversible with natural vitamin A? Med Hypoth.
2000;54:979-983.
75. Bhaskaram P. Immunobiology of mild
micronutrient deficiencies. Br J Nutr.
2001;85:S75-S80.
76. Richer JM, Cross RG. Gaze aversion in autistic
and normal children. Acta Psychiatr Scand.
1976;53:193-210.
77. Schuil J, van de Putte EM, Zwaan CM, et al.
Retinopathy following measles, mumps, and
rubella vaccination in an immuno-incompetent
girl. Int Opthalmol. 1998;22:345-347.
78. Fan PC, Teug RJ, Chou CC, et al. Impaired
immune function in a premature infant with zinc
deficiency after total parenteral nutrition. Chung
Hua Min Kwo Hsiao Erh Kol Hsueh HUI Tsa
Chih. 1996;37:64-69.
79. Sazawal S, Jalla S, Mazumder S, et al. Effect of
zinc supplementation on cell-mediated immunity
and lymphocyte subsets in preschool children.
Indian Pediatr. 1997;34:589-597.
©
80. Folwaczny C. Zinc and diarrhea in infants. J Trace
Elem Med Biol. 1997;11:116-122.
81. Walker-Smith JA, Andrews J. Alpha-antitrypsin,
autism and celiac disease. Lancet. 1972;2:883-884.
82. Goodwin MS, Cowen MA, Goodwin TC.
Malabsorption and cerebral dysfunction: A
multivariate and comparative study of autistic
children. J Autism Child Schizophr. 1971;1:48-62.
83. Horvath K, Tildon J. The role of secretin in
autistic spectrum disorder. Int Rev Research
Mental Retard. 2001;23:33-54.
84. D'Eufemia P, Celli M, Finocchiaro R, et al.
Abnormal intestinal permeability in children with
autism. Acta Paediatr. 1996;85:1076-1079.
85. Shaw W, Kassen E, Chaves E. Increased urinary
excretion of analogues of Krebs cycle metabolites
and arabinose in two brothers with autistic
features. Clin Chem. 1995;41:1094-1104.
86. Reichelt KL. Biochemistry and psychophysiology
of autistic syndromes. Tidsskr Nor Laegeforen.
1994;114:1432-1434.
87. Shattock P, Kennedy A, Rowell F, et al. Role of
neuropeptides in autism and their relationships
with classical neurotransmitters. Brain
Dysfunction. 1991;3:328-325.
88. Knivsberg AM, Reichelt KL, Nodland M. Reports
on dietary intervention in autistic disorders. Nutr
Neurosci. 2001;4:25-37.
89. Zioudrou C, Streaty RA, Klee WA. Opioid
peptides derived from food proteins. The
exorphins. J Biol Chem. 1979;254:2446-2449.
90. Fukudome S, Yoshikawa M. Gluten exorphin c. A
novel opioid peptide derived from wheat gluten.
FEBS Lett. 1993;316:17-19.
91. Chabance B, Marteau P, Rambaud JC. Casein
peptide release and passage to the blood in
humans during digestion of milk or yogurt.
Biochime. 1998;80:155-165.
92. Zagon IS, McLaughlin PJ. Endogenous opioid
systems regulate cell proliferation in the
developing rat brain. Brain Res. 1987;412:68-72.
93. Hauser KF, McLaughlin PJ, Zagon IS.
Endogenous opioid systems and the regulation of
dendritic growth and spine formation. J Comp
Neurol. 1989;281:13-22.
94. Barrett AJ, ed. Handbook of proteolytic enzymes.
Academic Press; 1998:379-382.
95. Srikantaiah MV, Radhakrishnan AN. Studies on
the metabolism of vitamin B6 in the small
intestine: Part III-purification and properties of
monkey intestinal pyridoxal kinase. Indian J
Biochem. 1970;7:151-156.
96. Rimland B. High dose vitamin B6 and magnesium
in treating autism: Response to study by Findling
et al. J Autism Dev Disord. 1998;28:581-582.
97. Scriver CR, Beaudet AL, Sly WS, et al, eds. The
metabolic and molecular bases of inherited disease.
New York: McGraw-Hill; 1995:1725-1768.
98. Stubbs G, Litt M, Lis E, et al. Adenosine
deaminase activity decreased in autism. J Amer
Acad Chld Psychiatr. 1982;21:71-74.
99. Pangborn JB, Baker SM. Biomedical assessment
options for children with autism and related
problems. San Diego, CA: Autism Research
Institute;2001:54.
100.Lai Ping So A, Mayer L. Gastrointestinal
manifestations of primary immunodeficiency
disorders. Semin Gastroinstest Dis. 1997;8:22-32.
101.Washington K, Stenzel TT, Buckley RH, et al.
Gastrointestinal pathology in patients with
common variable immunodeficiency and X-linked
agammaglobulinemia. Am J Surg Pathol. 1996;
20(10):1240-1252.
102.Ojuawo A, Milla PJ, Lindley KJ. Non infective
colitis in infancy: evidence in favor of minor
immunodeficiency in its pathogenesis. East Afr
Med J. 1997;74:233-236.
103.Klein N, Jack D. Immunodeficiency and the gut:
clues to the role of the immune system in
gastrointestinal disease. Ital J Gastroenterol
Hepatol. 1999;31:802-806.
laboratorymedicine> september 2002> number 9> volume 33
Downloaded from http://labmed.oxfordjournals.org/ by guest on April 12, 2016
36. Bernard S, Enayati A, Binstock T, et al. Autism: A
unique type of mercury poisoning. Cranford, NJ:
ARC Research; 2000: 1-76. Available at:
www.autism.com/ari/mercurylong.html. Accessed
August 7, 2002.
37. SafeMinds Website Available at:
www.dmcreative.tmp.com/safeminds/board.htm.
Accessed June 24, 2002.
38. McGinnis WR. Mercury and autistic gut disease.
Environ Hlth Persp. 2001;109:303-304.
39. Chen W, Body RL, Mottet NK. Biochemical and
morphological studies of monkeys chronically
exposed to methylmercury. J Toxicol Environ Hlth.
1983;12:407-416.
40. Horvath K, Papadimitriou JC, Rabsztyn A, et al.
Gastrointestinal abnormalities in children with
autistic disorder. J Pediatr. 1999;135:559-563.
41. Stejskal VD, Forsback M, Nilsson R. Lymphocyte
transformation test for diagnosis of isothiazoline
allergy in man. J Invest Derm. 1990;94:798-802.
42. Stejskal VD, Cederbrandt K, Lindvall A, et al.
MELISA-an in vitro tool for the study of metal
allergy. Toxicol in Vitro. 1994;8:991-1000.
43. Stejskal VD, Forsbeck M, Cederbrant KE.
Mercury-specific lymphocytes: An indication of
mercury allergy in man. J Clin Immunol.
1996;16:31-40.
44. Tibbling L, Thuomas KA, Lenkei R, et al.
Immunological and brain MRI changes in patients
with suspected metal intoxication. Int J Occupat
Med Toxicol. 1995;4.
45. Stejskal VD, Danersund A, Lindvall A, et al.
Metal-specific lymphocytes: Risk factors in CFS
and other related diseases. Neuroendocrinol Lett.
1999;20:289-298.
46. Stejskal VD. Human hapten-specific lymphocytes:
Biomarkers of allergy in man. Drug Info J.
1997;31:1379-1382.
47. Pang PK, Shan JJ, Lewanczuk RZ, et al. Parathyroid
hypertensive factor and intracellular calcium
regulation. J Hypertens. 1996;14:1053-1060.
48. Lewanczuk RZ, Benishin CG, Shan J, et al.
Clinical aspects of parathyroid hypertensive factor.
J Cardiovasc Pharmacol. 1994;23:23-26
49. Tessier-Lavigne M, Mobbs P, Attwell D. Lead and
mercury toxicity and the rod light response. Invest
Opthalmol Vis Sci. 1985;26:1117-1123.
50. Ritvo ER, Creel D, Realmuto G, et al.
Electroretinograms in autism: A pilot study of bwave amplitudes. Am J Psychiat. 1988;145:10851086.
51. Verstraeten T, David R, Destefano F. Risk of
neurological and renal impairment associated with
thimerosal-containing vaccines. Report to the
Advisory Committee on Immunization Practices;
Atlanta GA: June 21, 2000.
52. Finegan J, Quarrington B. Pre-, peri-, and neonatal
factors and infantile autism. J Child Psych
Psychiatr. 1979;20:119-128.
53. Stejskal J. Measles lymphadenopathy. Ultrastruct
Pathol. 1980;1:243-247.
54. Dankova E, Kasal P, Bergmannova V, et al.
Immunological findings in children with abnormal
reactions after immunization. Cesk Pediat.
1993;48:9-12.
55. Wakefield AJ, Murch SH, Linnell J, et al. Ileallymphoid-nodular hyperplasia, non-specific
colitis, and pervasive developmental disorder in
children. Lancet. 1998;351:637-641.
56. Wakefield AJ, Anthony M, Murch SH, et al.
Enterocolitis in children with developmental disorders.
Am J Gastroenterol. 2000;95:2285-2295.
57. Walker-Smith J. Letter: Autism, bowel inflammation,
and measles. Lancet. 2002;359:705-706.
58. Furlano RI, Anthony A, Day R, et al. Colonic
CD8 and gamma delta T-cell infiltration with
epithelial damage in children with autism. J
Pediatr. 2001;138:366-372.
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