Transcript 5 - Immune System - malfunctions

Aim: How can the immune system
malfunction?
How can your immune system
malfunction?
1.
2.
3.
4.
Allergies
Asthma
Autoimmune Disease
Organ Transplants
What is an allergy?
• An allergy is a rapid
immune system reaction
to environmental
substances that are
normally harmless.
• Can you think of
materials that can cause
allergic reactions?
What are things that cause allergies?
Allergens
Medicine
INSECT
Stings
FOOD
POLLEN
ANIMAL
FUR
RAGWEED
HOUSE DUST
MOLD
Allergic reactions
• Inflammatory response:
allergen attaches to mast cells
which release histamines.
• Histamines are chemicals that
can trigger an inflammatory
response (increase blood vessel
permeability)
• Hives, nausea, or shock
• What can we take for allergies?
Asthma can be an allergic reaction
Extrinsic Asthma
• In response to an
allergen, histamine
causes a contraction of
smooth muscles.
• How does this cause
the symptoms of
asthma?
•Histamine Reaction causes respiratory
passages to constrict or swell up.
Allergies
Autoimmune disease
The immune
system fails to
distinguish
between self and
non-self cells.
The word "auto" is the Greek word for
self. If a person has an autoimmune
disease, the immune system mistakenly
attacks self, targeting the cells, tissues, and
organs of a person's own body.
Examples of Autoimmune diseases
Diabetes is a
disease, which
prevents the body
from properly
using food energy.
In Multiple
Sclerosis, the
immune system
attacks the
protective coating
around nerves,
called myelin.
Rheumatoid arthritis
Joints swell
Why are organ transplants difficult?
• This is a kidney
being removed from
a donor
• The donor will have
his own ID tags on
the cell membrane.
What are these ID
tags called?
How will the recipient react?
• A transplanted organ is recognized as
foreign and is attacked by the immune
system (REJECTION).
• The chance of REJECTION is less when
the donor and recipient are closely related
or when anti-rejection medication is used.
Why take an immunosuppressant?
It will suppress your immune
system and reduce the chance
of destroying the transplanted
organ.
What is the risk of suppressing
the immune system?
It increases the patient’s risk for
an infection.