WEBVTT

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The body’s immune system protects it
against harmful external invaders.

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It:

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• fights off pathogens
(bacteria, viruses, fungi, parasites)

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• combats aberrations such as cancer cells

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• neutralizes environmental toxins.

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The immune system has
specialized defense cells

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as well as specific antibodies.

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These can identify “intruders”
from certain features,

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such as
protein structures on their surface,

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as foreign substances.

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This triggers an immune response,

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where specific immune cells
are placed on alert:

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They attack them directly or produce
antibodies or inflammatory substances

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that attack the intruders

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and neutralize them.

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The immune system is a finely tuned system,

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but it can sometimes mistakenly attack
the body’s own tissue.

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It produces antibodies

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that destroy healthy cells or tissues
by mistake.

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This often involves “autoantibodies”,

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antibodies that bind specifically
to certain cells in the body.

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Many immune cells
attack the body’s cells or tissue directly.

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This is then referred to
as an “autoimmune response”.

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Conditions caused
by this sort of misdirected immune response

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are referred to as autoimmune diseases.

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The best known of these include:

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• chronic inflammatory bowel disease,
e.g. ulcerative colitis

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• type 1 diabetes

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• Hashimoto’s thyroiditis
(chronically inflamed thyroid)

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• multiple sclerosis

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• rheumatoid arthritis

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• psoriasis

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• lupus erythematodes.

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In type 1 diabetes, for example,

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the immune system attacks pancreatic cells

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which produce the hormone insulin:

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The body needs insulin
to control blood glucose levels.

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The misdirected attack
damages the cells so severely

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that they can no longer produce insulin
or produce very little.

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This increases the blood glucose level.

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If left untreated,

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this can damage blood vessels
and cause cardiovascular disease.

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In rheumatoid arthritis

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the autoimmune response
is directed at the joints.

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This causes inflammation that destroys
cartilage, ligaments and bones.

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This is usually accompanied
by deformation of joints,

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particularly on the knees and hands.

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If the condition progresses
the inflammation can also spread

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to other parts of the body.

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In psoriasis
inflammatory processes

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cause a rapid increase in
proliferation of keratogenic skin cells.

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These cells rise
to the top layer of the skin

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where they normally fall off
as dead cells after 4 weeks.

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In psoriasis this process is sped up
and only takes 4 days.

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So dead skin cells are produced faster
than they fall off.

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This makes the skin thicker and very scaly.

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Genetics and environmental factors

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are likely to be responsible
for the onset of this condition.

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Nothing can be done
to prevent the cause of autoimmune disease,

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but there are various treatment approaches
that can mitigate symptoms.

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In short:

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• The immune system specializes
in fighting off pathogens,

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combating cancer cells
and neutralizing environmental toxins.

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To do this
it has large amounts of immune cells

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that are able
to identify foreign structures.

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If an immune response is triggered
the system produces specific antibodies

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that attack and destroy foreign structures.

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Sometimes the system attacks the body’s
healthy cells or tissue by mistake.

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This is then referred to
as an “autoimmune response”.

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Examples of known autoimmune diseases
include type 1 diabetes,

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rheumatoid arthritis and psoriasis.