1. The Immune System

2. The First Lines of Defense: – Skin – Antimicrobial proteins – Cilia – Gastric Juice – Symbiotic bacteria – your ‘microbiome’

3. This is directly from the Cliffs book...so make sure you read that Second Line of Defense – Phagocytes – Complement – promote cell lysis – Interferons - ‘interfere’ with viral reproduction – Inflammatory response Histamine Vasodilation Phagocytes Complement

5. Immune Response The Third Line of Defense: – This targets specific antigens – any molecule that can be identified as foreign

6. Major Histocompatibility Complex The MHC allows the immune system to differentiate between self and non-self cells. - Made up of glycoproteins - Found on the membranes of all body cells - 20 genes code for these; unlikely that two people have the same set

7. Lymphocytes! Primary Agent of the Immune Response – B Cells – originate and mature in the Bone Marrow – Respond to antigens through antigen receptors called antibodies Y shaped proteins, 5 different classes

8. 5 Classes of Antibodies

9. T cells Lymphocytes that originate in the bone marrow but mature in the thymus gland – Have antigen receptors, but they are not antibodies – You should read up on the additional information...

10. Responses of the Immune System- 1.CELL MEDICATED 2.HUMORAL Cell-mediated response – Uses T cells to respond to any non self cell, including cells invaded by pathogens.

11. Cell Mediated Response

12. The Humeral Response Involves most cells and responds to antigens or pathogens - B cells produce plasma cells - B cells produce memory cells - Macrophage and helper T cells stimulate the production of additional B cells

14. Why aren’t we dead? 1. Antibodies 2. Vaccines 3. Passive Immunity – placenta, breast milk