Midterm Part 2

Question 1

What kinds of cells does chronic inflammation involve?

Answer 1

(Years): characterized by the activation of macrophages and T cells

Question 2

What do TLRs bind to?

Answer 2

PAMPS

Question 3

(Step 1 of inflammatory response)

• What transcription factor does the TLR/PAMP interaction produce?
• What cytokines are produced as a result of this reaction?

Answer 3

• nF-KB

- IL-1, IL-6, TNFa +CXCL8

Question 4

What cells initiate the inflammatory response?

Answer 4

• macrophages and mast cells

Question 5

What is the effect of histamine?

Answer 5

Histamine causes blood vessels to dilate, thus increasing blood flow to the area and resulting in the redness and heat association with inflammation

Question 6

What is extravasation?

Answer 6

adhesion molecules allow leukocytes such as neutrophils and monocytes to stick to the endothelial cells of the blood vessel and then squeeze through the spaces between the endothelial cells of the blood vessel and into the tissue

Question 7

What is the function of CXCL8?

Answer 7

guides the neutrophils, monocytes and dendritic cells to location of the bacteria in the tissues.

Question 8

What do neutrophils do? What makes them good at their job? How many pathogens can they kill?

Answer 8

• phagocytose pathogen
• there are a lot of them
• 1 pathogen

Question 9

What is the function of monocytes? Why are they good at killing cells?

Answer 9

• to mature into macrophages and then phagocytose

- expert phagocytes, can kill 100s of cells

Question 10

How do neutrophils and monocytes kill pathogens?

Answer 10

• phagocytosis
• pathogen goes into a phagosome, and is then acidified and membrane-bound granules called lysosomes fuse with the phagosome to form a phagolysosome

Question 11

What are the 5 steps of the inflammatory response?

Answer 11

1. RECOGNITION: PRR/PAMP interaction releases alarm cytokines
2. INITIATION: Macrophages and mast cells initiate inflammatory response, cause vasodilation and increased vascularity
3. CELLULAR INFILTRATION: Neutrophils and macrophages are recruited and phagocytose
4. Clotting and repair
5. Pus

Question 12

Does The innate immune response vary between a first and a second exposure to a pathogen?

Answer 12

No

Question 13

True or false: within minutes, vasodilation occurs and brings leukocytes to the site of infection

Answer 13

False (within hours)

Question 14

Where are mast cells found? What is the structure of the cell? What do they do?

Answer 14

- Rare in blood, tissue resident
• Small nucleous, 
granule-rich cytoplasm
• Release granule 
contents (histamine) to 
trigger reactions

Question 15

Where are DC’s found? Where do they go when they are activated?

Answer 15

• in tissues

- secondary lymphoid organs

Question 16

What is a sign of a non-self microorganism?

Answer 16

1. Cell wall components
      • LPS, peptidoglycan
2. Flagella 
      • flagellin
3. Nucleic acids 
      • Bacterial DNA
      • dsRNA in viruses

Question 17

What are the two kinds of PRR’s? What are the outcomes of the two kinds of PAMP/PRR interactions?

Answer 17

Phagocytosis receptors and TLRs

• phagocytic: contains the infection
• TLRs: call for help

Question 18

(Fourth step of inflammatory response) How does the body clot/repair skin?

Answer 18

• coagulation proteins and platelets are recruited

- Macrophages replace the scab

Question 19

Where does the DC activate the B and T cells?

Answer 19

The lymph nodes

Question 20

Where does adaptive immunity begin?

Answer 20

The secondary lymph organs

Question 21

What do B and T cells do in the absence of infection?

Answer 21

Circulate through the lymph nodes looking for pathogens

Question 22

How is the adaptive immune system initiated?

Answer 22

DC’s phagocytose pathogen in the tissue, and travel to the lymph nodes (tissue infection) or spleen (systemic infection) to activate T cells

Question 23

Where do DC’s mature?

Answer 23

In the lymph nodes or spleen

Question 24

What is an antigen?

Answer 24

A protein that is recognized by lymphocytes

Question 25

Which cells present antigen?

Answer 25

ALL cells can present antigen, but only some cells are professional APCs

Question 26

What are the three types of professional APCs?

Answer 26

1. DC (happens early, can travel)
2. Macrophage (happens later, cannot travel)
3. B cell (happens later, to efficiently activate more Th cells)