Word Count: 1429
The human immune system is an amazing system that is constantly on the alert
protecting us from
sicknesses. Thousands of white blood cells travel in our circulatory system destroying all
foreign
substances that could cause harm to our body or to any of the millions of processes going
on inside. Now
imagine a condition where this awesome system turns against the most complex organ in
the human body,
the brain. Deadly as it is, this condition is known as Rasmussen’s encephalitis.
The meaningful research on Rasmussen’s encephalitis was begun (unintentionally)
by Scott Rogers
and Lorise Gahring, two neurologists, who were at the time measuring the distribution of
glutamate
receptors in the brain. Later on when more provocative information was found they
enlisted the help of
James McNamara and Ian Andrews, epilepsy experts at Duke University Medical Center.
The details on Rasmussen’s encephalitis were very bleak at the time when the men
began their
research. All that was known is that Rasmussen’s encephalitis was a degenerative
disease of the brain
that caused seizures, hemiparesis, and dementia normally in the first ten years of life.
The seizures that
were caused by Rasmussen’s encephalitis were unstoppable by normal anti-seizure drugs
used
conventionally. What the worst part of the disease was that the pathogenesis for it were
not known and
even worse was how it developed.
The first clue was delivered when Rogers and Gahring were trying to register the
distribution of the
glutamate receptors using antibodies, that tag on to the receptor itself. The proteins that
make up the
glutamate receptors(GluR) are only found inside the blood brain barrier(BBB).
Glutamate and a few
related amino acids are the dominant form of excitatory neurotransmitter in the central
nervous system of
mammals. If one of these GluRs happens to wander into the actual bloodstream, that is
outside the BBB,
it would be considered an outsider and destroyed immediately. So if these GluRs were
put into the normal
blood stream then the immune system would produce antibodies which could then be
used in the
searching for the glutamate receptors.
In order to test this theory the researchers injected the GluRs into the blood stream
of a normal
healthy rabbit hoping to produce good results. At this point the experiment took a
dramatic turn, after
receiving a few doses of the protein two of the three rabbits began to twitch, as though
they were suffering
the pain of an epileptic seizure. Now the help of McNamara and Andrews was enlisted.
When McNamara and Andrews examined the brain tissue of the rabbits, they saw
what seemed to be
a familiar inflammatory pattern, clumps of immune cells all around blood vessels. This
description
exactly matched the description of persons suffering from Rasmussen’s encephalitis,
moreover something
as this would never be found in a healthy brain. A healthy brain has its blood capillaries
enclosed in the
BBB membrane, so such a case as the one mentioned above would not be possible.
As protective as the BBB is, it can be breached by something like a head injury.
What was
happening was that the antibodies which were out to get the GluR proteins were
somehow finding a way
into the brain and directing an attack towards all GluR receptor proteins in the brain
itself.
After some more examinations Rogers and McNamara decided that these attacks
were the cause of
the seizures that are often experienced by sufferers of Ramussen’s encephalitis. Then if
the case is of
antibodies in the bloodstream, than sufferers of Ramussen’s encephalitis should have
them in their
bloodstream and healthy normal peoples shouldn’t. When this was actually tested the
results were
positive that Rasmussen sufferers did have these antibodies in their bloodstreams and
healthy people did
not. These were not only the right kind of antibodies but, the very antibodies that caused
the seizures in
people and rabbits. Thus when these antibodies were removed by plasma
exchange(PEX) it caused a
temporary relief from the seizures but soon the body starts making more antibodies of the
type and the
seizures start once again. After all the examinations two questions remained, why does
the body mount
an immune response against one of its own brain proteins, and how do these antibodies
get through the
BBB?
What is thought right now is that people get antibodies when they are infected by a
microorganism
like a bacterium or a virus that is similar in structure to the GluR. When this happens the
body mounts an
immune response against, and it just so happens that at this stage you suffer a blow to the
head. This will
open your BBB to the antibodies and they will attack the friendly GluRs in the brain,
causing seizures and
further opening your BBB to more antibodies.
Now a malicious rhythm begins: antibodies break through the BBB, inflammation
is caused due to
the break in, seizures are now caused and BBB opens up further, further opening in the
BBB cause more
seizures. The inflammation is caused by the autoimmune process against the GluR. All
the seizures
occur where the initial break in the BBB happened due to a blow to the head, explaining
why they
seizures are confined to just one hemisphere. The only problem with this theory is that
the rabbits
developed seizures without ever being whacked on the head, but that also could be
because a rabbit’s brain
is not as well insulated as a human’s.
Normally what happens to an individual is that after he or she is involved in this
cycle the only
thing that can make for relief is the recurrent plasma exchange. This will only cease the
seizures
temporarily, but they will start again when the body has made more new antibodies.
After this has been
done many times the hemisphere in which sufferers of Ramussen’s encephalitis is present
will deteriorate
to the point where a hemispherectomy has to be performed. This will render the person
to mental
disintegration where he or she has no more mental capacity and generally to the point of
no return, death.
Rasmussen’s encephalitis is a very deadly disease, but it is also a very rare disease,
occurring in only
48 people between 1957 and 1987. As of now there are no FDA approved drugs for the
sufferers of
Ramussen’s encephalitis. Now the researchers are working on a drug that will block the
activity of this
particular antibody, but this could lead to further problems. If this drug is being
administered and a
bacteria or virus of a similar structure as the GluR is present the body would disregard it
and this would
cause more health problems. After all this bad news all one can say is, "Good
luck" to the ones suffering
from this living hell.
Atkins, "Rasmussen’s encephalitis: nueroimaging findings in four
patients." AJR-Am-JRoentgenol. June 1992.
Blume, "Rasmussen’s chronic encephalitis in adults." ArchNuerol. March 1993.
Hanovar, "Rasmussen’s encephalitis in surgery for epilepsy."
Dev-Med-Child-Nuerol.
January 1992.
Leary, "Clues Found To Rare Form of Epilepsy." New York
Times. December 5 1994,
pp. A4.
Whisenand, "Autoantibodies to glutamate receptor GluR3 in Rasmussen’s
encephalitis,"
Science. July 29 1994.
Keywords:
word count human immune system amazing system that constantly alert protecting from
sicknesses thousands white blood cells travel circulatory system destroying foreign
substances that could cause harm body millions processes going inside imagine condition
where this awesome turns against most complex organ human body brain deadly this
condition known rasmussen encephalitis meaningful research rasmussen encephalitis
begun unintentionally scott rogers lorise gahring neurologists were time measuring
distribution glutamate receptors brain later when more provocative information found
they enlisted help james mcnamara andrews epilepsy experts duke university medical
center details rasmussen encephalitis were very bleak time when began their research that
known degenerative disease brain caused seizures hemiparesis dementia normally first
years life seizures were caused unstoppable normal anti seizure drugs used
conventionally what worst part disease pathogenesis known even worse developed first
clue delivered when rogers gahring trying register distribution glutamate receptors using
antibodies receptor itself proteins make glutamate receptors glur only found inside blood
barrier related amino acids dominant form excitatory neurotransmitter central nervous
mammals these glurs happens wander into actual bloodstream outside would considered
outsider destroyed immediately these glurs into normal blood stream then immune would
produce antibodies which could then used searching order test this theory researchers
injected glurs into stream normal healthy rabbit hoping produce good results point
experiment took dramatic turn after receiving doses protein three rabbits began twitch
though they suffering pain epileptic seizure help mcnamara andrews enlisted mcnamara
andrews examined tissue rabbits they what seemed familiar inflammatory pattern clumps
immune cells around vessels description exactly matched description persons suffering
from moreover something would never found healthy healthy capillaries enclosed
membrane such case mentioned above possible protective breached something like head
injury what happening antibodies which glur proteins somehow finding directing attack
towards glur receptor proteins itself after some more examinations rogers decided these
attacks cause seizures often experienced sufferers ramussen then case bloodstream than
sufferers ramussen should have them their bloodstream peoples shouldn actually tested
results positive sufferers have their bloodstreams people only right kind very caused
people rabbits thus removed plasma exchange temporary relief from soon body starts
making more type start once again after examinations questions remained does mount
response against through thought right people infected microorganism like bacterium
virus similar structure happens mounts response against just happens stage suffer blow
head will open your will attack friendly causing further opening your malicious rhythm
begins break through inflammation break opens further further opening cause
inflammation autoimmune process occur where initial break happened blow head
explaining confined just hemisphere only problem with theory developed without ever
being whacked also could because rabbit well insulated human normally individual
involved cycle thing make relief recurrent plasma exchange will cease temporarily start
again made been done many times hemisphere which ramussen present deteriorate point
where hemispherectomy performed render person mental disintegration mental capacity
generally point return death very deadly disease also rare occurring between there
approved drugs researchers working drug block activity particular antibody lead
problems drug being administered bacteria virus similar structure present disregard health
problems news quot good luck quot ones suffering living hell atkins quot nueroimaging
findings four patients roentgenol june blume chronic adults arch nuerol march hanovar
surgery epilepsy child nuerol january leary clues rare form epilepsy york times december
whisenand autoantibodies receptor science july
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