Inflammation

Question 1

What is inflammation?

Answer 1

• Coordinated response by vascularised tissue to injury or microorganism
• Can be harmful and beneficial (prolonged and painful or quick and increases blood supply)

Question 2

What does acute mean?

Answer 2

Initial and often transient

Question 3

What does chronic mean?

Answer 3

Prolonged reaction

Question 4

Describe the vascular events on inflammation

Answer 4

• Plasma proteins go to damaged tissue
• Increased blood flow and endothelial permeability
• Exudate enters tissue
• In acute, dilated blood vessels, inccreased lymph flow leads to oedema

Question 5

Describe the cellular events of inflammation

Answer 5

• Delivers white blood cells to damaged tissue
• Sent to a specific site
• Some inflammatory cells are present in tissue and others in circulation

Question 6

Describe adhesion and emigration

Answer 6

• Cells adhere to endothelium and cells communicate through receptors (cell adhesion moleucles- CAM)
• Selectin and integrin integrate with extracellular matrix of other cells
• Increased CAMs with inflammation, adhesion allows migration

Question 7

What is chemotaxis?

Answer 7

Signal that is responded to by movement

Question 8

Describe inflammatory cell functions

Answer 8

• Phagocytosis, antibodies, killing infected host cells, contolling inflammatory reactions
• Too much- destroys too much tissue
• Too little - not all harmful material destroyed

Question 9

Describe endothelial cells (adhesion- non-inflammatory)

Answer 9

• CD (receptors)- cluster of differentiation (sometimes specific)
• CD31- marker for endothelial cells

Question 10

Describe cellular interactions

Answer 10

• Chemical messengers- prostaglandins, cytokines, complement and clotting factors
• Cell to cell- endothelial calls and neutrophils
• Pro-inflammatory and anti-inflammatory
• Neutrophils flow in middle of vessel (lobular)
• Margination (to side), neutrophils adhere to endothelial cells, emigration to the basal lamina

Question 11

Describe leucocytosis

Answer 11

• Neutrophils are the first wbc to enter inflamed tissue and phagocytose
• Pus- accumulation of neutrophils and pyogenic bacteria
• Abcess- collection of pus in tissues

Question 12

Describe the systemic effects of inflammation

Answer 12

• Mediated by cytokines
• E.g. IL1 and IL6, TNF- tumour necrosis factor, produced by cells in inflamed tissue
• Pyrexia- fever, malaise- tiredness, anorexia, weight loss, leucocytosis (increased WBC) and acute phase proteins

Question 13

What are the cardinal signs of inflammation?

Answer 13

• Heat (calor)
• Redness (rubor)
• Swelling (tumour)
• Pain (dolor)
• Loss of function