Acute and Chronic inflammation

Question 1

What is acute inflammation?

Answer 1

Response of living tissue to infection/damage
Develops quickly
Initiation for innate immunity

Question 2

What are the three processes involved in acute inflammation?

Answer 2

Vascular dilation
Increased vascular permeability
Neutrophil activation and migration

Question 3

What are the four main causes of acute inflammation?

Answer 3

Microbial infection
Resulting from microbial recognition Physical agents, Physical trauma
Ultraviolet or other ionizing radiation, Heat (burns), Cold
Irritant and corrosive chemicals
Acids, alkali, oxidizing agents
Microbial virulence factors
Tissue necrosis
Lack of oxygen or nutrients
Inadequate blood flow (infarction)

Question 4

What are the consequences of acute inflammation?

Answer 4

Redness (rubor)
Dilation of small blood vessels
Heat (calor)
Increased blood flow (hyperaemia)
Swelling (tumor)
Accumulation of fluid in extra vascular space (oedema)
Pain (dolor)
Stretching/distortion of tissues due to oedema.
Chemical mediators induce pain
Loss of function

Question 5

what is an example of acute inflamation?

Answer 5

gingivitis

Question 6

What is meant by amplification?

Answer 6

recruitment and activation of innate immune cells via chemokine/cytokine activity and vascular dilation

Question 7

what is the vascular response to acute inflammation?

Answer 7

Small blood vessels adjacent to site of damage become dilated
Endothelial cells swell and retract
Exudation – the vessels become ‘leaky’ and allow passage of water, salts and some proteins
Endothelial cells activated to promote immune cells passage to damaged tissues

Question 8

What is oedema?

Answer 8

defined as excess of watery fluid collecting in the cavities or tissues of the body.
increased blood and lymph flow.

Question 9

in tissues what allows for the diffusuion of mediators?

Answer 9

salt and fluids

Question 10

Give 3 examples of mediators involved in inflammation

Answer 10

chemical- Histamine
Bradykinin
Leukotrienes
Serotonin
Prostaglandins
Protein- cytokines, chemokines

Question 11

Describe and explain histamines role here?

Answer 11

Product of breakdown of amino acid histidine
Stored in granules of immune cells such as mast cells
Degranulation releases histamine
Role as a neurotransmitter – itching
Causes vascular dilation
Many immune cells express histamine receptors

Question 12

Describe prostaglandins and explain their role.

Answer 12

Produced by macrophages and neutrophils (with leukotrienes)
Product of fatty acid metabolism
Most abundant is Prostaglandin E2 (PGE2)
Causes vascular dilation
other roles- Regulate cytokine production
Regulate cell recruitment
Act on nerve fibres – pain
Involved in tissue remodeling

Question 13

What are the 4 enzymatic cascades?

Answer 13

Complement (covered in innate immunity II)
The kinin system
Coagulation
Fibrinolytic system

Question 14

describe a complement cascade?

Answer 14

3 pathways
Classical pathway – antibody attached to microbe
(2) Alternative pathway – microbial cell wall
(3) Mannose binding lectin pathway (MBL) – carbohydrates on pathogen surface

Question 15

what is generated by Hageman factor?

Answer 15

Kallikrein

Question 16

In the kinin system what does Kallikrein convert?

Answer 16

Kallikrein converts kininogens to kinins (e.g., bradykinin)

Question 17

what do all three pathways of the coagulation system result in?

Answer 17

Production of thrombin which in turn produces fibrin (clot formation)
intrinsic and extrinsic

Question 18

What does the fibrinolytic system result in?

Answer 18

activation of plasmin

Question 19

What is involved in the fibrinolytic system?

Answer 19

invokved in blood clots

Question 20

The balance between which two systems is essential for homeostasis?

Answer 20

Coagulation and fibrinolytic

Question 21

Acute inflammation leads to what that chronic doesn’t?

Answer 21

resolution

Question 22

Absess formation (suppuration) is an outcome of what?

Answer 22

acute inflammation

Question 23

3 types of gingival absesses?

Answer 23

Gingival abscess
Periodontal abscess
Periapical abscess

Question 24

What is the difference between acute and chronic inflammation?

Answer 24

accute- rapid (days)
chronic inflammation persistent can occur over months, years

Question 25

What are three types of chronic inflammation?

Answer 25

Non-specific chronic inflammation
specific (primary inflammation)
Chronic Granulomatous inflammation

Question 26

Describe non-specific chronic inflammation

Answer 26

Failure to resolve acute inflammation
Persistent bouts of acute inflammation
Excessive suppuration

Question 27

describe primary/ specific chronic inflammation

Answer 27

persistent exposure to agent
Can be non-granulomatous or granulomatous (type 3)
Characterized by excessively activated macrophages
Induced by: Non-immunological agents
Foreign body reactions
Inert noxious material (e.g. silica and asbestos)

Question 28

What can induce specific chronic inflammation?

Answer 28

Induced by: Immunological agents
Infective organisms that grow in cells
Hypersensitivity reactions (Lecture 10)
Autoimmune reactions
Infection by fungi, protozoa or parasites

Question 29

How does Rheumatoid arthritis develop?

Answer 29

PAD enzymes (Peptidyl arginine deiminase) – naturally produced by host cells such as neutrophils but also produced by Pgingivalis
This enzyme citrullinates proteins – arginine conversion to citrulline which is not a normal naturally occurring amino acid
The host see this amino acid as a a foreign body – attack it (loss of tolerance)

Question 30

describe chronic granulomatous inflammation

Answer 30

Differs from normal chronic inflammation as the predominant cell types are modified activated macrophages;
Known as epithelioid macrophages
Giant cells (multi-nucleated: formed from fused epithelioid macrophages)
Also B and T cells present in tissue.

Question 31

describe chronic granulomatous inflammation

Answer 31

Differs from normal chronic inflammation as the predominant cell types are modified activated macrophages;
Known as epithelioid macrophages
Giant cells (multi-nucleated: formed from fused epithelioid macrophages)
Also B and T cells present in tissue.

Question 32

What causes chronic granulomatous inflammation?

Answer 32

Causes;
Immunological (delayed hypersensitivity type reaction or invading pathogens)
Non-immunological (Foreign body in tissue e.g. asbestos particles)

Question 33

What is orofacial Granulomatosis (OFG) an example of?

Answer 33

chronic granulomatous inflammation

Question 34

What macrophages are essential in repair?

Answer 34

M1 V M2