1. Dr. Mauricio Rodriguez-Lanetty
PCB4233: Immunology
Dr. Mauricio Rodriguez-Lanetty
Phone:
Lecture 2

2. Special forces of high specialization
Skin
Blood vessel
Special forces of high specialization
Troop (library) of soldiers (T/B cells)
Recognition & Activation

3. Special forces of high specialization
Skin
Blood vessel
Special forces of high specialization
Immunological memory
Troop (library) of soldiers (T/B cells)

4. How these special cells (T/B) does not attack self cells in the body?
Skin
Blood vessel
Special forces of high specialization
Immunological memory
Troop (library) of soldiers (T/B cells)
How these special cells (T/B) does not attack self cells in the body?

5. Special forces of high specialization
Skin
Blood vessel
Special forces of high specialization
Immunological memory
Troop (library) of soldiers (T/B cells)
Factory of T/B Cells

6. Special forces of high specialization
Skin
Blood vessel
Special forces of high specialization
Immunological memory
Troop (library) of soldiers (T/B cells)
Education Center for T-cells
(Army Academy)
Education Center for B-cells
(Army academy)
Factory of T/B Cells

7. Special forces of high specialization
Skin
Blood vessel
Special forces of high specialization
Immunological memory
Troop (library) of soldiers (T/B cells)
Don’t target/kill cells from your own body
Education Center for T-cells
(Army Academy)
Education Center for B-cells
(Army academy)

8. Special forces of high specialization
Skin
Blood vessel
Special forces of high specialization
Immunological memory
Troop (library) of soldiers (T/B cells)
Education Center for T-cells
(Army Academy)
Education Center for B-cells
(Army academy)
Factory of T/B Cells

9. Innate Immune System Adaptive Immune System
Skin
Innate
Immune
System
Blood vessel
Adaptive Immune
System
Special forces of high specialization
Immunological memory
Troop (library) of soldiers (T/B cells)
Education Center for T-cells
(Army Academy)
Education Center for B-cells
(Army academy)
Factory of T/B Cells

10. Secondary lymphoid organs Primary / Central lymphoid organs
Skin
Innate
Immune
System
Blood vessel
Adaptive Immune
System
Special forces of high specialization
Secondary lymphoid organs
Immunological memory
Troop (library) of soldiers (T/B cells)
Primary / Central lymphoid organs
Education Center for T-cells
(Army Academy)
Education Center for B-cells
(Army academy)
Factory of T/B Cells

12. Pattern Recognition Receptors (PRRs)
Receptors with specificity for pathogens molecules
Pattern Recognition Receptors (PRRs)
This receptors recognize repeating patterns of molecular structure carried by microorganisms/pathogens on their surfaces
The pathogen-associated molecular patterns that PRR recognize are called PAMPs (MAMPs)

13. The pathogen-associated molecular patterns that PRR recognize are called PAMPs

14. The Innate immune recognition by Toll-like receptors (TLR)
Toll-like receptors belong to an evolutionarily ancient recognition and signaling system
Discovered from embryonic development studies in fruitfly
Found to have a role in the defense against bacterial and fungal infections
In Drosophila is Toll, and the homologous protein in mammals and other animals are therefore known as Toll-like receptors

15. There are 10 expressed TLR genes in mice and humans

16. Infection stimulates macrophages to release cytokines and chemokines that initiate an inflammatory response
Chemokines function mainly as chemoattractants for leukocytes, recruiting monocytes, neutrophils, and other effector cells from the blood to sites of infection

17. Infection stimulates macrophages to release cytokines and chemokines that initiate an inflammatory response
The recruitment of activated phagocytes to sites of infection is one of the most important functions of innate immunity

18. Important cytokines secreted by macrophages in response to
bacterial products

19. Important cytokines secreted by macrophages in response to
bacterial products

20. Chemokines can be produced by a wide variety of cell types in response to bacterial products, viruses, and agents that cause physical damage.
Thus, infection or physical damage to tissues sets in motion the production of chemokine gradients that can direct phagocytes to the sites where they are needed.

21. Neutrophils • Normal adult releases1-3 x 1010 neutrophils per day from
Bone Marrow
• Primary function is phagocytosis and killing of pathogens
• To do so neutrophils must gain access to tissues from
the bloodstream – extravasation
Neutrophils are the first cells to bind to inflamed tissue, and therefore to arrive in large numbers at a site of infection, with monocytes and immature dentritic cells being recruited later.

22. Neutrophils moving through the circulation system: ROLLING

23. Neutrophils leave the blood and migrate to sites of infection in a multi-step process

24. Steps in neutrophil extravasation
• Rolling. Recognition of inflamed tissue
• Activation by chemoattractants
• Arrest and adhesion
• Transendothelial migration
• Chemotaxis towards source of infection
Same principles as for T cell migration in lymph nodes

25. Macrophages and neutrophils are not only brought to potential sites of infection by chemokines but in the process they are also armed to deal with any pathogen they may encounter there.
In particular neutrophils exposed to CXCL8 and cytokyne TNF-α are activated to produce the respiratory burst that generates oxygen radicals, nitric oxide, and to release their stored lysosomal contents.

26. Some differences between INNATE and ADAPTIVE immunity

27. Reading Material Chapter 1 and 2
That is all for today
Thanks for coming!
Reading Material Chapter 1 and 2