1. Brief introduction to the immune system

2. Review
Which constituent of blood fights off infection?

3. Review Which constituent of blood fights off infection? White
Blood cells!
But…
How do they
do this?

4. Antigens
Antigens are small substances (usually on the surface of cells) that may trigger an immune response.
Your immune system will attack antigens that it does not recognize.

5. How does it do this?
Antibodies are small Y-shaped proteins that are produced in plasma. They neutralize foreign pathogens, or ”tag” foreign pathogens to be destroyed by white blood cells.

6. Antigens and antibodies simulation

7. White blood cells destroy pathogens by engulfing them
White blood cells destroy pathogens by engulfing them. This means that they surround them and ingest them. This process is called phagocytosis.

8. How do vaccinations work?
Vaccinations typically give you a very small dosage of a weakened pathogen. Your immune system will ”learn” from this and form antibodies to fight it next time.
Have you ever had chickenpox?

9. Not all viruses and pathogens are treatable
The Human Immunodeficiency Virus (HIV) destroys white blood cells, leaving the body defenseless.
This leads to a condition called Acquired Immune Deficiency Syndrome (AIDS).

10. Your red blood cells have antigens too
There are 3 types of antigens that your blood cells may or may not have.
Antigen A
Antigen B
Antigen Rh This antigen was first isolated in Rhesus monkeys

11. Rhesus factor
If you have the Rh antigen, you have a positive blood type.
If you do not have the Rh antigen, you have a negative blood type.