Download Acquired immunity

Immune System
Immune System
A body system to fight off
foreign invaders….
Immune System
Star Wars- Immune
System
Immune System
Disease - A failure of homeostasis
Pathogens
Disease-causing organisms
Enter the body:

Respiratory System

Digestive System

Urinary System

Breaks in the Skin
First Line of Defense
Physical Barriers

skin, membranes
Chemical Barriers

sweat, tears, saliva, mucus, stomach
acid, urine
Second Line of Defense
Inflammatory Response: Histamine
Reaction that causes swelling, redness, warmth
and pain in an area of infection
Blood vessels: expand and white blood cells
leak from the vessels to enter the infected
tissue
Chemicals are released which increase body
temperature (fever)
Second Line of Defense

Phagocytes are attracted to the area and
engulf bacteria
phagocytosis animation
Increased Temperature

Slows growth of pathogen

increases rate of chemical reactions

increases heart rate so WBCs get to site of
infection faster
inflammatory response animation
Third Line of Defense:
The Immune System
Lymphocytes ( WBCs)
(B cells, Helper T cells, Killer T cells)
lymphocyte animation
IMMUNITY
The ability of the body to fight
infection through the protection of
antibodies and cells that inactivate
foreign substances.
Fig. 43-1
1.5 µm
BASIS OF IMMUNITY
The ability of the body to
distinguish between its own
substances “SELF” and foreign
substances “NON-SELF”
BASIS OF IMMUNITY
 Barriers
help an animal to defend itself from the
many dangerous pathogens it may encounter
 The
immune system recognizes foreign bodies
and responds with the production of immune
cells and proteins
 Two
major kinds of defenses are involved:
Innate immunity and Acquired immunity
BASIS OF IMMUNITY
Innate immunity
 is
present before any exposure to pathogens
and is effective from the time of birth
 It
involves Nonspecific responses to pathogens
ex: Phagocytes ( WBC’s) first attacking a
pathogen
BASIS OF IMMUNITY
Acquired immunity
 develops
after exposure to agents such as
microbes or other foreign substances
 It
involves a very Specific response to pathogens
Ex: T-Cells, B-Cells, Memory B-Cells and Antibodies
Acquired Immunity
 Acquired
immunity has two branches:

The humoral immune response

The cell-mediated immune response
Acquired Immunity
 Humoral
Immune Response:
Involves activation and clonal selection of
B-cells (Memory Cells) – involved in
production of antibodies
Acquired Immunity
 Cell-Mediated
Immune Response
Involves Killer T-cells and Helper T- Cells
Killer T-cells attack the pathogen,
causing fluid to leak out; cell ruptures
and dies
Helper T Cells aid both responses
Important Terms to Know
Important Terms to Know
ANTIGEN
A substance that causes an immune
response.

made of proteins. (Very Specific)
 EVERY
organism have specific antigens
that line the Surface of their Cells.
 Every
Organism has unique antigens
Important Terms to Know
 ANTIBODIES
(Y shaped)
Are proteins that are produced
by the help of white blood cells.
 Antibodies
bind to antigens and help destroy
foreign substances in the body.
Important Terms to Know

Antigen-Antibody Complex.
A particular antibody reacts
with a specific antigen
Fig. 43-10
Antibodies, Antigen and
Antigen-Antibody Complex
Antigenbinding
sites
Antigen-binding sites
Antibody A Antigen Antibody C
C
C
Antibody B
Epitopes
(antigenic
determinants)
ANTIBODIES
Important Terms to Know
 Lymphocytes
– White blood cells - found most often in the
lymphatic system
– Originate from stem cells in the bone
marrow
Lymphocytes
 Lymphocytes
that
mature in the Thymus
above the heart are
called T cells, and
those that mature in
Bone Marrow are called
B cells
Bone marrow
Thymus
Via blood
Immature
lymphocytes
B cell
T-cell
B-Cells
 B-Cells
are produced during an Immune
Response to produce Antibodies
 Some are stored as Memory Cells for future
exposures.
B-Cell Making Antibodies
T-Cells
T-Helper Cells help activate the B-cell by
producing special proteins
 T-Cytotoxic ( Killer ) Cell attack the invading
pathogen or “nonself ” Antigen

Cytotoxic
T cell
T-cell receptor
Cell-mediated
immunity
(attack on
infected cells)
Cell division
Activated
helper T
cell
Activates
other T cells
and B cells
Self-nonself complex
B cell
Humoral
immunity
(secretion of
antibodies)
Figure 24.13
T-Cells
T- Killer Cells :
T-Cells
T-Helper Cells – Activate T-Killer Cells
and Memory Cells
Organ Transplants
What do you think might happen after a Liver
or Heart Transplant?
Rejection
Why?
Antigens don’t match
See as NonSelf
How can doctors help minimize the bad
effects?
Immunosuppressant Drugs
Organ Transplants
Describe a problems with Immunosuppressant
Drugs
Organ Transplants
Describe a problems with Immunosuppressant
Drugs Risk of infections
TWO WAYS IMMUNITY
CAN BE ACQUIRED :

ACTIVE IMMUNITY: Antibodies are
made by one’s own body and are long
lasting.
A Persons Body actively makes the antibodies
TWO WAYS IMMUNITY
CAN BE ACQUIRED :
PASSIVE IMMUNITY: Antibodies are
obtained from the blood of another person or
animal, but only provides temporary
immunity. ( 1 Month )

PASSIVE IMMUNITY – Two Ways
Maternal Immunity:
 Antibodies
from
mother enter baby’s
blood before birth.
 Antibodies
are present
in mother’s breast
milk.
PASSIVE IMMUNITY
(TWO WAYS)
From other animals or
people:
The antibodies from
animals or people are
collected and used to
treat disease.
Ex. Anti-serum
ACTIVE IMMUNITY - Two Ways
 Can
develop as a result of having a
disease.
Memory cells remain in the body
ready to produce antibodies if the
pathogen invades the body again.
ACTIVE IMMUNITY - Two Ways
 Develops
as a result of getting a Vaccine.
A vaccine is made up of weakened or killed
micro-organisms to stimulate the body to
make antibodies used to fight future
invasions by the same microorganism.
VACCINES
Edward Jenner (1796)
 noticed
that people who
worked with cows rarely
contracted smallpox
 infected
an 8 year old boy
with cowpox, a mild disease
related to smallpox
Edward Jenner (1796)
 when
the boy recovered, Jenner
infected him with smallpox, but he
did not get sick
 first
vaccine
(“vacca” is Latin for cow)
HOW DOES A VACCINE
WORK?
1st:Micro-organism
(bacteria, virus) is
weakened or killed.
(NOT A SMALL AMOUNT)
2nd:Vaccine is injected.
3rd: Antibodies are
produced by WBC’s and
some stay as Memory B
cells. ( 2 weeks )
HOW DOES A VACCINE
WORK?
Then if……..
4th: The Same Microbe
invades body.
5th: Antibodies / Memory
Cells in body destroy the
microbes.
Disorders of the Immune System
Allergies
ALLERGIES

Occur when the body responds to everyday
substances as antigens & produce antibodies.
Ex. dust, pollen, mold, peanuts, animal hair

This causes inflammation and the release of a
chemical called histamine.

Histamine causes - red, itchy, watery eyes/nose,
itchy throat, rash, and headaches

Anti-Histamines- are drugs that counter act the
effects of the histamines. ( ex. Benadryl)
Fig. 43-23
Allergic Response
IgE
Histamine
Allergen
Granule
Mast cell
HIV
AIDS
Acquired Immune Deficiency Syndrome

AIDS is caused by the HIV virus
(Human Immunodeficiency Virus)

HIV invades white blood cells (T-Cells)
and transforms the T-Cell DNA with its RNA

Gradually HIV kills T-Cells and weakens a persons
immune response.

People die of illnesses brought on by a weak immune
system.
 The
spread of HIV is a worldwide problem
 The
best approach for slowing this spread is
education about practices that transmit the virus

There are Anti-Viral Medications that now help slow
the advancement of the disease
Autoimmune Diseases
 In
individuals with autoimmune diseases, the
immune system loses tolerance for self and turns
against certain molecules or parts of the body
Autoimmune diseases
1.
Juvenile diabetes- antibodies destroy the cells
of the pancreas that produce insulin
2.
Lupus- multiple antibodies affect different parts of
the body
3.
Rheumatoid Arthritis- inflammation and
crippling of the joints
4.
Multiple Sclerosis - antibodies attack the
myelin sheath of nerve cells
Fig. 43-24
Lupus
Fig. 43-24
Rheumatoid Arthritis
Cancer
T
cells search the body and destroy cancer cells in
healthy people

suppression of the immune system can result in
cancer
Human Blood Groups
Four types of human blood:
1.
Blood type O – no antigens present on RBC
2.
Blood type A – Type A antigens present on RBC
3.
Blood type B – Type B antigens present on RBC
4.
Blood type AB – Type A & B antigens present
on RBC
When wrong blood types are mixed in a transfusion,
RBC clump together and clog blood vessels
Rh Factor
 Another
subgroup of blood types is the Rh
group
 85%
population Rh Positive
 Can
cause problems with childbirth
BLOOD TYPING

Blood Typing Game

Get Ready to Play - Who Wants to be
The Doctor???????
ABO Blood Groups
Blood Type
A
B
AB
O
Antigens on
RBCs
Antibodies in
plasma
ABO Blood Groups
Blood Type
A
Antigens on
RBCs
A
Antibodies in
plasma
B
B
B
A
AB
A and B
none
O
none
A and B
Matching ABO Blood Types for
Transfusions
Recipient
A
B
AB
O
Donor
Matching ABO Blood Types for
Transfusions
Recipient
A
Donor
A, O
B
B, O
AB
A, B, AB, O
(universal recipient)
O
O
(universal donor)
For A Safe Blood Transfusion…
Recipient’s
blood can NOT contain
antibodies for donor’s blood.
Universal
Recipients = Blood type
AB
Universal
Donors = Blood type O
GIVE BLOOD