WK 3- INFLAMMATION PT.2

Question 1

What does collateral damage mean in reference to leukocytes

Answer 1

when leukocytes cause damage to normal cells and tissues through the release of ROS and enzymes

Question 2

What diseases does this collateral damage occur

Answer 2

Asthma, TB, MI, septic shock, ischemia reperfusion injury, auto-immune

Question 3

What causes leukocyte adhesion deficiency 1

Answer 3

-defective leukocyte adhesion because of mutations in the beta chain of CD II/CD18 Integrins

Question 4

What causes leukocyte adhesion deficiency 2

Answer 4

defective leukocyte adhesion because of mutations in fucosyl transferase required for synthesis of sialylated oligosaccharide (receptor for selectins)

Question 5

What are 2 examples of genetic leukocyte function disorders

Answer 5

Leukocyte adhesion deficiency 1 and 2

Question 6

How is acute inflammation terminated

Answer 6

• phagocytic cells clear necrotic tissue and bacteria
• inflammatory mediators released during acute inflammation have a short half life and therefore levels decline
• switch in pro-inflammatory metabolites to anti-inflammatory
• apoptosis of extravascular neutrophils

Question 7

What anti-inflammatory mediator prevents neutrophil adhesion and chemotaxis

Answer 7

lipoxin

Question 8

What are the 3 main outcomes that can result from acute inflammation

Answer 8

1. Complete resolution and restoration to normal state and function
2. Healing by connective tissue replacement (scarring) if occurs in non-regenerating tissues or in fibrin abundant environment
3. Acute inflammation will progress to chronic inflammation

Question 9

What is chronic inflammation

Answer 9

-prolonged process in which active inflammation, tissue destruction and healing all occur simultaneously

Question 10

What is granulomatous inflammation

Answer 10

caused by infection or inflammatory response-> is a distinct pattern of inflammation where the immune system attempts to wall of substances it knows is foreign but is unable to eliminate-> macrophages clump together to form Langhans cells with nuclei lining the periphery

Question 11

What are the two outcomes of tissue repair

Answer 11

Regeneration and Resolution

Question 12

What is regeneration

Answer 12

• occurs after a mild injury where only the epithelium but not the underlying tissue is damaged, happens in tissues with a high proliferative capacity
• structure/cells will completely return to normal

Question 13

What is resolution/repair by scar formation

Answer 13

• repair by scar formation
• occurs after a more severe injury where there is connective tissue damage
• there will restoration of some normal structure but with deficits

Question 14

What are the 3 factors that influences scar formation

Answer 14

1. Capacity of the tissue to regenerate
2. Extent of injury
3. Extent of fibrosis driven by the mediators of chronic inflammation

Question 15

What are the 3 types of proliferative tissues

Answer 15

1. Labile (continuously diving)
2. Stabile (quiescent)
3. Permanent (non-dividing)

Question 16

What is an example of a labile (continuously dividing) tissue

Answer 16

Proliferate throughout life-> surface epithelia and haematopoietic cells

Question 17

What is an example of a permanent (non-dividing) tissue

Answer 17

Can’t undergo division post-natal-> neurons

Question 18

What is an example of a stable (quiescent) tissue

Answer 18

Involved in low-level replication-> liver

Question 19

What are the 3 steps in scar formation

Answer 19

1. Formation of new blood vessels (angiogenesis)
2. Migration and Proliferation of fibroblasts and deposition of connective tissue (granulation tissue)
3. Maturation and reorganization of fibrous tissue (remodelling) to produce a stable fibrous scar