This document discusses various topics related to the immune system, including: - Antigens and how the immune system distinguishes self from non-self. - Issues with blood transfusions, organ transplants, and antibody recognition. - Autoimmune diseases like lupus and multiple sclerosis where the immune system attacks the body's own tissues. - Immunodeficiency from HIV/AIDS where the virus depletes immune cells. - Allergic reactions where the immune system incorrectly identifies harmless antigens as threats. - Asthma as an allergic condition affecting the lungs. - The immune system's role in detecting and eliminating cancer cells.

1. Other
Topics –
Related
to
Immune
System

2. Other Topics – Related
to Immune System
• Antigens- “marker proteins”
• Blood Transfusions and Organ
Transplants
• It is the job of the immune system to
distinguish between the body’s own
molecules and foreign molecules

3. If the key fits the lock = bad!!!
Blood Transfusions and the Immune
System
• Blood cells have marker proteins or
“antigens”

4. Organ Transplants and the
Immune System
• Foreign organs also have marker
proteins.
• If recognized as “foreign” = REJECTION.
• Doctors must “match” a new organs
marker proteins to the patients.
• Drugs can help suppress the immune
response (immunosuppresants).

5. What if the immune
system fails?
• Sometimes the immune system loses the
ability to distinguish itself from non-self.
• Results in autoimmune disease
• Body attacks own tissues
• Ex) lupus, multiple sclerosis, arthritis

6. LUPUS
• Person’s immune system attacks various
organs or cells of the body (skin, joints,
kidneys, heart, and lungs) causing
damage
• Lupus is a multi-system disease because
it can affect many different tissues and
organs in the body.

7. LUPUS
Symptoms:
• Fatigue
• Low-grade fever, rarely exceeding 102°F
• Muscle pain and joint pain or swelling
• Skin rash (face, back, arms) and hair loss
• Kidney problems and weight loss

9. Multiple
Sclerosis
• Immune system
attacks mylein
around nerve cells
• Symptoms: loss ability to walk and move,
loss bladder control, paralysis and death

10. What if the immune
system fails?
• Sometimes the immune system collapses
• Ex) HIV
• Virus invades macrophages and helper T
cells
• Without these WBC immune response
will not work
• Body becomes overwhelmed with
pathogens (HIV  AIDS)

11. AIDS (Acquired Immune
Deficiency Syndrome)
• Retrovirus (has RNA instead of DNA).
• Lysogenic (stays dormant for a long
period of time).
• Easily evades immune system.
1. Mutates quickly.
2. Covers itself with marker proteins from
host cell (difficult to detect).

12. Transmission of HIV
• Four main ways
1. Sexual intercourse.
2. Intravenous drug use (sharing needles)
3. Blood to blood contact
4. Mother to child during pregnancy or
breast feeding.

13. What if the immune
system fails?
• Sometimes the immune
system overreacts
thinking something is a
pathogen when it is NOT
• Allergy- immune system
response to a non-
pathogenic antigen
• Ex) pollen, food, insect
bite, dust, etc.

14. Steps – Allergic
Reaction
• 1) Pollen inhaled
• 2) cells of nasal
passage called mast
cells release chemical-
histamine
• 3) nearby capillaries
swell- increases fluid
*Allergies are treated
with medication that
contains
antihistamines
(chemical that blocks
histamine)

15. Asthma
• Leading cause of serious illness among
children.
• Causes narrowing of air passages (people
can’t breathe).
• Can be triggered by stress, environmental
factors, allergies, or genetic factors.
• Medication (usually a steroid) needs to be
taken to make breathing easier.

17. Immune System and
Cancer
• Major function of immune system is to
patrol for cancer cells
• Called Immunological Surveillance
• Killer-T cells can identify, attack, and
destroy cancer cells