The Cells involved in inflammation

Question 1

What is inflammation?

Answer 1

A local protective response to eliminate the initial cause of tissue cell injury as well as necrotic cells resulting from the initial insult

Question 2

What are the 5 pillars of inflammation?

Answer 2

• Heat
• Redness
• Swelling
• Pain
• Loss of function

Question 3

What are the roles of inflammation?

Answer 3

• Alert the body to infection and injury
• Regulate influx of leukocytes that can resolve the injury
• Facilitate immune responses
• Dilute noxious components
• Remove damaged tissue
• Initiate the tissue repair process

Question 4

What are the orchestrators of inflammation?

Answer 4

• Tissue resident macrophages and mast cells
• Blood vessel endothelial cells
• Soluble components released by immune cells at site of infection
• Soluble components in serum

Question 5

What are the effects of TNF-α and IL-1 on endothelial cells in blood vessels?

Answer 5

• Endothelial cells retract
• Causes increase in vascular permeability
• Blood vessels dilate
• Blood flow slowed

Question 6

What is the principal role of mast cells?

Answer 6

To act as communication cells

Question 7

What cells recognise tissue damage in the inflammatory response?

Answer 7

Macrophages and mast cells

Question 8

Why are blood cells made leaky by the inflammatory response?

Answer 8

It makes it easier for additional immune cells to move from the blood to the site of inflammation

Question 9

Outline how immune cells leave the blood

Answer 9

• Rolling on the walls of the blood vessels
• Adhesion and transmigration
• Migration through tissues towards chemotactic stimulus

Question 10

What is the normal velocity of a cell in the blood?

Answer 10

4000um/s

Question 11

What is the velocity of an immune cell when it is rolling?

Answer 11

40um/s

Question 12

What kind of chemicals are involved in the process of rolling?

Answer 12

Selectins

Question 13

What is the role of selectins?

Answer 13

They mediate the process of rolling by binding to selected carbohydrate groups

Question 14

What are the 3 types of selectin?

Answer 14

• E-selectin
• P-selectin
• L-selectin

Question 15

Where is E-selectin found?

Answer 15

On the endothelium

Question 16

Where is P-selectin found?

Answer 16

On platelets and the endothelium

Question 17

Where is L-selectin found?

Answer 17

On leukocytes

Question 18

What is the seqeuence of events in acute inflammation?

Answer 18

• Oedema
• Neutrophil recruitment
• Monocyte/macrophage recruitment

Question 19

What is a catch bond?

Answer 19

A bond that strengthens under force

Question 20

What type of selectins are upregulated by inflammatory mediators?

Answer 20

E and P

Question 21

What does L-selectin bind to?

Answer 21

CD34

Question 22

Outline the process of rolling

Answer 22

• E and P selectins are upregulated by inflammatory mediators
• These bind glycoproteins on leukocyte
• L-selectin binds CD34 on the endothelium
• Due to selectin binding leukocytes roll on the blood vessel walls

Question 23

What is chemotaxis?

Answer 23

The cellular migration up a concentration gradient of a diffusable protein

Question 24

Where is CXCL8 (IL-8) produced in acute inflammation?

Answer 24

The endothelium

Question 25

Which chemokine is produced in chronic inflammation?

Answer 25

CCL2

Question 26

Which chemokine is produced in acute inflammation?

Answer 26

CXCL8 (IL-8)

Question 27

What is an integrin?

Answer 27

A protein which mediates tight adhesion of blood vessels and leukocytes

Question 28

Give 3 examples on integrins

Answer 28

• LFA-1
• VLA-4
• Mac-1

Question 29

What is the ligand of LFA-1?

Answer 29

ICAM-1

Question 30

What is the ligand of VLA-4?

Answer 30

VCAM-1

Question 31

Where is VLA-4 found?

Answer 31

On mucosal T cells

Question 32

What is the ligand of Mac-1?

Answer 32

It has over 40 reported ligands including ICAM-1

Question 33

What increases expression of ICAM-1 and VCAM-1?

Answer 33

TNF-α and IL-1