Lecture 12:Innate mechanisms

Question 1

What are the five associations of inflammation

Answer 1

• redness
• swelling
• heat
• pain
• loss of function

Question 2

What three things does inflammation cause

Answer 2

• vascular permeability
• cellular recruitment
• cellular proliferation and metabolism

Question 3

What is one of the main roles of inflammation

Answer 3

Bring leukocytes and plasma proteins to a site of infection

Question 4

What is vascular permeability

Answer 4

• Increased cell and plasma proteins entering the tissue

- increased lymph drainage

Question 5

What is inflammation overall mediated by?

Answer 5

Cytokines, chemokines and other soluble mediators

Question 6

What are cytokines

Answer 6

Small proteins released by cells usually in response to a stimulus

Question 7

What do cytokines do

Answer 7

Induce a response in a target cell by binding to a cytokines receptor

Question 8

What are the four cytokine families

Answer 8

• interleukins
• hematopoietins
• tumour-necrosis factor
• interferons

Question 9

What are chemoattractant cytokines

Answer 9

• Cytokines that induce cellular adhesion

- directional cell migration in response to a gradient of the chemokine

Question 10

Which specific type of receptors do chemokines belong to

Answer 10

Conserved class of 7-transmembrane G-protein coupled receptors

Question 11

Name the three steps of inflammation

Answer 11

• vasodilation
• increased vascular permeability
• influx of phagocytic leukocytes

Question 12

When does inflammation occur

Answer 12

• infection
• injury
• organ abnormalities (tumour, stroke)

Question 13

What are the 4 changes to the vasculature resulting from inflammation

Answer 13

• vascular dilation (blood flow)
• endothelium expression of adhesion molecules
• vascular leakage
• clotting

Question 14

What is vascular dilation

Answer 14

Increased blood flow

Question 15

What do adhesion molecules help with

Answer 15

Recruitment of leukocytes

Question 16

What is vascular leakage

Answer 16

Fluid and plasma proteins (complement and antibodies) enter the tissue (swelling pain)

Question 17

What is the purpose of clotting in inflammation

Answer 17

Blocks the vessels preventing pathogen spread

Question 18

What is the local response in the vasculature from inflammation mediated by?

Answer 18

Lipid mediators released from macrophages and neutrophils

Question 19

Do all soluble mediators act locally

Answer 19

No

Question 20

What systemic wholistic changes can occur from inflammation

Answer 20

• fever
• increased cellular proliferation and mobilization from the bone marrow
• increased plasma protein production by liver
• mobilization of energy stores (ATP)

Question 21

Is all inflammation good

Answer 21

No, too much can lead to organ failure and death

Question 22

What are the fundamental problems with getting innate immune cells to a site of infection

Answer 22

• cells circulate all throughout the body
• cells are flying past spots
• need to get out of blood and into tissue
• leukocytes need to home in on pathogen

Question 23

How does the endothelium become activated

Answer 23

• detection of pathogen by macrophage or DC cell in tissue
• results in production of cytokines and chemokines
• cytokines and chemokines activate endothelium
• activated endothelium expresses adhesion molecules and additional chemokines

Question 24

Why don’t all leukocytes get recruited to a site of infection

Answer 24

• differential expression of adhesion molecules

- differential expression of chemokine receptors