Inflammation and Neutrophils

Question 1

What is a type of granulocyte?

Answer 1

Neutrophil

Question 2

A neutrophil is also known as PMN. What does this stand for?

Answer 2

Polymorphonuclear leucocyte

Question 3

Where does neutrophil come from?

Answer 3

Recruited from the Bone Marrow
Large amounts

Question 4

The action of neutrophil

Answer 4

Short lived (6hrs)
First line of defense
Detect and phagocytose pathogens

Question 5

Killing mechanism of neutrophils

Answer 5

Lysosomal Killing mechanisms
- granules
-peptides and enzyme

Question 6

Which chemokine initiates the recruitment of neutrophils?

Answer 6

IL-8, C5a
Attracts neutrophil to site of infection

Question 7

Example of enzyme/

Answer 7

Myeloperoxidase
Green
Formation of pus

Question 8

What cell produces histamine?

Answer 8

Mast cell
First line of defense
Increase vessel leakiness

Question 9

Mechanism

Answer 9

Leukocyte Extravasation

Question 10

Key steps of leukocyte extravasation

Answer 10

1. Chemoattraction
2. Tethering and rolling
3. Migration

Question 11

What is chemoattraction?

Answer 11

Sensing of pathogen in the tissue

Question 12

A type of Leukocyte is?

Answer 12

Neutrophil

Question 13

Why do leukocytes carry receptors?

Answer 13

Recognize chemokines

Question 14

What cells line the blood vessel?

Answer 14

Endothelial cells

Question 15

What do endothelial cells carry?

Answer 15

Adhesion molecules
-E/P selectin

Question 16

What are expressed by leukocytes?

Answer 16

Glycan structures

Question 17

What are in between 2 endothelial cells?

Answer 17

Tight junctions

Question 18

Where are leukocytes found?

Answer 18

Blood vessel lumen

Question 19

What is expressed on the surface of neutrophils and what does it interact with?

Answer 19

Sialyl Lewis X (sugar like structure)
Interacts with P/E selectin on endothelial cell

LFA-1 inactive integrin
Binds to selectins on endothelial cell

Question 20

Receptor binding on neutrophil and endothelial cells facilitates…

Answer 20

Transient adhesion and slowing down of neutrophil

Question 21

Lymphocytes express

Answer 21

L-selectin

Question 22

Up regulation of cytokines will increase expression of …

Answer 22

P/E selectin

Question 23

Tighter interaction of neutrophil and endothelial cell is facilitated by

Answer 23

LFA-1 inactive integrin

Question 24

Migration

Answer 24

Squeeze through tight junctions

Question 25

How is LFA-1 activated?

Answer 25

Cross-linking Conformation Change

Question 26

What is the arrest stage?

Answer 26

1. Chemokine - IL-8, C5a 2. ICAM-1, activation of endothelial cells -> increases expression of adhesion molecules 3. LFA-1 Active Integrin - conformation change -allows tighter binding

Question 27

Extravasation

Answer 27

Open tight Neutrophil squeezes between endothelial cells into tissues attracted by chemokines at the site of infection Phagocytosis and effector mechanism directed at the pathogen

Question 28

Co-receptors for HIV entry

Answer 28

CXCR4 (T cells) CCR5 (monocytes)