Acute Inflammation

Question 1

Acute Inflammation and its functions

Answer 1

Rapid Response of vascularised tissue to injury

• Eradicates cause of injury
• Remove damaged cellular material
• Initiates repair process

(Think of out of control house party and the cleanup the morning afterwards; kicking out people who are still there, tidy up the mess, call somebody repair broken windows and such)

Question 2

What can trigger acute inflammation

Answer 2

Infection
Trauma
Necrosis
Immune Reactions
Foreign bodies

Question 3

What happens during acute inflammation

Answer 3

1. Vasodilation - Local blood vessels briefly contract then dilate to slow blood flow to the area (within seconds, mediated by mast cells and NO2 from endothelial cells); this slowing allows neutrophils to come into contact with endothelium
2. Increased vascular permeability - Tight junctions between capillary endothelial cells loosen and leak fluid rich in mediators to surrounding tissue (contains neutrophils, come macrophages and lymphocytes, plasma and proteins - lots of fibrinogen), causes swelling
3. Cellular Activation/Migration - [Neutrophils are made to adhere to endothelium, increased motility allows emigration from blood vessels to surrounding tissue]

Question 4

How do cells roll across blood vessels

Answer 4

Cell adhesion molecules (e.g. selectins and integrins) on the endothelial cells enable macrophages to adhere to them and slip out of the vessel then migrate to the wound and do their shit

Question 5

Phagocytosis in inflammation

Answer 5

WBCs (neutrophils and macrophages but less so) in large numbers leave the blood and engluf/neutralise foreign particles; the activation of the WBCs makes it easier for them to leave the blood and be more efficient at phagocytosis

Question 6

Describe the life span of neutrophils during activity

Answer 6

Clearing cellular debris then getting full up and dying - short lived

Question 7

Phagosome

Answer 7

Vesicle formed around a particle engulfed by a phagocyte via phagocytosis

Question 8

Compare phagocytosis by macrophages and neutrophils

Answer 8

Phagocytosis by macrophages is slower and less of a burst so they can keep going back. They become more and more useful the longer that the inflammation lasts

Question 9

Suffix -itis

Answer 9

Acute inflammation of x

e.g. gastritis - inflammation of stomach

pleurisy (exception) - inflammation of gas around lungs

Question 10

Examples of bad inflammation

Answer 10

Autoimmune disorders like rheumatoid arthritis, allergies, strong response to a severe infection

Question 11

What does bradykinin mediate

Answer 11

It mediates pain

Question 12

Answer 12

Question 13

Systemic (full body) effects of acute inflammation

Answer 13

Neutrophilia
Fever
Fatigue
Loss of Appetite
Increased acute phase proteins in blood

Question 14

Where do systemic effects of acute inflammation come from

Answer 14

They are mediated by cytokines (mainly from activated macrophages) which act on the brain in the acute inflammatory response as well as on the bone marrow to increase neutrophil production

Question 15

How long does acute phase response take and what are the 3 acute phase proteins

Answer 15

Onset within hours - days

Fibrinogen
C Reactive Protein (CRP)
Serum Amyloid A (SAA)

Question 16

Which cytokines upregulate acute phase proteins the most; where do they come from

Answer 16

TNFα, IL-1 (increases SAA), IL-6 (increases CRP and fibrinogen)

They come from macrophages