The Immune System
Objectives
SWBAT describe and interpret the
function of the immune system and its
major cells including macrophages,
antibodies, T-cells, etc.
Celiac Disease
• Immune Reaction to gluten (protein in wheat,
barley, and rye)
• Gluten triggers an immune response in the small
intestine
• This produces inflammation and damages the small
intestine lining… which leads to ____________
• Treatment:
▫ Strict non-gluten diet
What does the immune system
do?
Fight off infection by keeping foreign (not
suppose to be there) cells OUTSIDE the body
and by making cells that kill those bad cells if
they get in.
2 Types of Defenses
Nonspecific = guards against
everything equally; does not pick
and choose
Specific = targets individual (one
type of) invaders
Nonspecific Defenses:
1st Line
Skin, mucus, sweat,
tears
Skin is the most
important
nonspecific defense
Keep pathogens
(organisms that can
infect) outside
How? Enzymes and
acid in secretions kill
bacteria
Nonspecific Defenses:
2nd Line
Pathogens that enter
release toxins causing
inflammatory
response
Your body makes
millions of white blood
cells to fight the
intruder
Body raises temperature
to kill pathogens (fever)
Review
• Pathogen tries to invade your cell- what does it
encounter?
• Compare this to a line of defense for a sport.
Specific Defenses
Specific attacks are triggered by antigens
Antigen = foreign substance such as
virus, bacteria, or other pathogen (intruder)
Our bodies have a few specific attackers:
B cells
T cells
Specific Defense:
Humoral Immunity (B Cells)
B cells recognize
antigens
B cells make antibodies
Antibodies recognize
and bind (connect) to
antigens to kill/inactivate
them
Memory B cells also
made to help fight off
future invasions faster
The Last Line
Specific Defense:
Cell-mediated immunity
If the pathogen gets by all
other defenses and into
the cell, this is how to
solve the problem:
Killer T cells track down
and destroy cells with
antigens inside
Memory T cells are
made to recognize
antigen if it invades again
Review
• A pathogen breaks through your skin. What
does it encounter?
• Compare this to a sport.
Check For Understanding
Does your skin choose which pathogens to
protect you from?
So skin is an example of a
nonspecific
______________
immune defense
Any Killer T cell can kill any cells
infected by a pathogen (bad invader)
True or False
Once your body makes more
antibodies to the flu, you have the
antibodies to fight all viruses.
True or False
Cartoon
• YOU (individually) will turn in a cartoon
depicting the different types of cells in your
immune system.
• Half = Specific; other half of the room = nonspecific
• End of class- share with a neighbor
• Ms. Lin will show an example.
• Anything unfinished will be homework.
Scenario 1: Non-specific
• Its Monday. The teacher has moved your seat.
Your new neighbor smells like he hasn’t
showered in weeks. In the middle of lecture your
neighbor falls asleep and unfortunately, his body
slumps over onto yours. His drool and snot gets
all over your arm.
• Describe your body’s first line of defense in a
comic book style format. Include pictures and
descriptions.
Scenario 2: Specific
• Its Tuesday. Thanks to your first line of defense
you have survived David the Drooler. But,
unfortunately for you, Melvin was absent the
day his kindergarten teacher discussed not
walking around with scissors. During an activity
Melvin trips over someone’s soccer equipment
bag and stabs you right in the arm with a pair of
scissors! Oh no! The scissors are loaded with
germs! The germs have clearly gotten past your
first line of defense. Describe your body’s
second line of defense in a comic book style
format. Include pictures and descriptions.