Inflammation 1 (Acute)

Question 1

What are the vascular changes in inflammation

Answer 1

1. Vasodilation 2. Increased vascular permeability.

Question 2

Which chemicals mediate the vascular changes?

Answer 2

1. Histamine. 2. Nitric Oxide.

Question 3

Clinical signs of vascular changes?

Answer 3

1. Heat (calor) 2. Redness (rubor)

Question 4

What is White cell margination and how does it occur?

Answer 4

Vasodilation slows the rate of blood flow. Allows White blood cells to move peripherally, to the endothelium of the vessel, i.e Margination.

Question 5

How does adhesion take place?

Answer 5

Endothelial cells express protein receptors to which white blood cells attach loosely

Question 6

What happens in rolling?

Answer 6

Due to the loose attachment, the WBC’s bind and detach from the adhesion molecules, moving along the endothelium as they do so. This is rolling.

Question 7

What are selectins? Function?

Answer 7

Receptors found in leukocytes and endothelium. Facilitate the weak binding seen in Rolling.

Question 8

What are integrins? Function?

Answer 8

Receptors found on leukocytes that bind to ligands on the endothelium. Mediate firm adhesion.

Question 9

What are VCAMS and ICAMS?

Answer 9

Adhesion molecules found in endothelial cells.

Question 10

What is the role of TNF and IL-6 in VCAM/ICAMS?

Answer 10

Increase the expression of VCAMS and ICAMS.

Question 11

Which two inflammatory mediators increase selectin expression?

Answer 11

Histamine and Thrombin

Question 12

What is diapedesis?

Answer 12

Leukocytes move through the vessel wall, by squeezing inter-endothelial spaces of the endothelium. This is known as diapedesis.

Question 13

What is chemotaxis?

Answer 13

Leukocytes follow a chemical gradient of C5a protein (highest in injury site), to reach the site of injury.

Question 14

What is phagocytosis?

Answer 14

Engulfment and degradation of pathogens by phagocytes.

Question 15

How do phagocytes recognise + attach to the foreign body?

Answer 15

1. Mannose receptors- expressed on the surface of bacterial glycoproteins. Phagocytes express cells that can bind to mannose receptors.
2. Scavenger Receptors- Phagocytes recognise low density lipoproteins found in pathogens.
3. Opsonins- Antibody or complement proteins that can recognise Bacterial surface proteins. Opsonins mark these bacteria, making it easier for phagocytes to identify and kill them.

Question 16

What is the process of phagocytosis?

Answer 16

Phagocyte engulfs the bacteria, forms phagosome. Phagosome + lysosome= phagolysosome Stimulates killing + degradation.

Question 17

Which substances mediate cell kiling?

Answer 17

1. ROS- Oxygen gains an electron from NADPH to become superoxide. 2. RNS- NO combines with superoxide to form ONOO.

Question 18

What are the clinical featurs of inflammation?

Answer 18

1. Redness 2. Swelling. 3. Heat 4. Pain.

Question 19

Which white blood cell is key to Acute Inflammation?

Answer 19

Neutrophils- multi lobed nucleus. Granulocytes. Phagocytic and cytotoxic abilities.