Download Lecture 2 - IMaGeS Lab

PCB4233: Immunology
Dr. Mauricio Rodriguez-Lanetty
Email: [email protected]
Phone: 305-3484922
Lecture 2
Skin
Blood vessel
Special forces of
high specialization
Troop (library) of
soldiers (T/B cells)
Recognition &
Activation
Skin
Blood vessel
Special forces of
high specialization
Immunological
memory
Troop (library) of
soldiers (T/B cells)
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?
Skin
Blood vessel
Special forces of
high specialization
Immunological
memory
Troop (library) of
soldiers (T/B cells)
Factory of T/B
Cells
Skin
Blood vessel
Special forces of
high specialization
Immunological
memory
Education Center
for T-cells
(Army Academy)
Troop (library) of
soldiers (T/B cells)
Factory of T/B
Cells
Education Center
for B-cells
(Army academy)
Skin
Blood vessel
Special forces of
high specialization
Immunological
memory
Education Center
for T-cells
(Army Academy)
Troop (library) of
soldiers (T/B cells)
Don’t target/kill
cells from your
own body
Education Center
for B-cells
(Army academy)
Skin
Blood vessel
Special forces of
high specialization
Immunological
memory
Education Center
for T-cells
(Army Academy)
Troop (library) of
soldiers (T/B cells)
Factory of T/B
Cells
Education Center
for B-cells
(Army academy)
Skin
Innate
Immune
System
Blood vessel
Adaptive Immune
System
Special forces of
high specialization
Immunological
memory
Education Center
for T-cells
(Army Academy)
Troop (library) of
soldiers (T/B cells)
Factory of T/B
Cells
Education Center
for B-cells
(Army academy)
Skin
Innate
Immune
System
Blood vessel
Adaptive Immune
System
Special forces of
high specialization
Immunological
memory
Education Center
for T-cells
(Army Academy)
Secondary
lymphoid
organs
Troop (library) of
soldiers (T/B cells)
Factory of T/B
Cells
Education Center
for B-cells
(Army academy)
Primary /
Central
lymphoid
organs
Skin
Innate
Immune
System
Blood vessel
Adaptive Immune
System
Special forces of
high specialization
Immunological
memory
Education Center
for T-cells
(Army Academy)
Troop (library) of
soldiers (T/B cells)
Factory of T/B
Cells
Education Center
for B-cells
(Army academy)
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)
The pathogen-associated molecular patterns that PRR
recognize are called PAMPs
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
There are 10 expressed
TLR genes in mice and
humans
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
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
Important cytokines secreted by macrophages in
response to
bacterial products
Important cytokines secreted by macrophages in
response to
bacterial products
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.
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.
Neutrophils moving through the circulation
system: ROLLING
Neutrophils leave the blood and migrate to
sites of infection in a multi-step process
Steps in neutrophil
extravasation
• Rolling. Recognition of
inflamed tissue
• Activation by
chemoattractants
• Arrest and adhesion
• Transendothelial migration
Same principles as for T cell migration in lymph nodes
• Chemotaxis towards source
of infection
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.
Some differences between INNATE and
ADAPTIVE immunity
That is all for today
Thanks for coming!
Reading Material Chapter 1 and 2