Inflammation Flashcards
1
Q
What are the functions of inflmmation?
A
- Non-specific immune response (same for all injury’s)
- Limits the spread of pathogens or destroys them outright
- Removes any cell debris and pathogens from damaged tissue
- Sets the stage for tissue repair
- Alerts the adaptive immune system to the threat of infection
2
Q
What are the cardinal signs of acute inflammation?
A
- Heat
- Redness
- Swelling
- Pain
3
Q
Explain the cardinal sign of heat of acute inflammation
A
- hyperaemia
- increased blood flow
- promotes metabolic rate of cells leading to faster repair process
- also inhibits migration of bacteria stemming infection
4
Q
explain the cardinal sign of redness for acute inflammation
A
- vasodilation of blood vessels increasing blood flow
- hyperaemia
- meaning more blood cells, inflammatory chemicals needed for tissue repair
5
Q
Explain the cardinal sign of swelling of acute inflammation
A
- increased permeability of blood vessels
- more fluid leaking from capillaries into interstitial space between tissue cells
- limits the movement of injury site so enhance speed of repair also preventing injury to surrounding tissue
6
Q
Explain the cardinal sign of pain in acute inflammation
A
- chemicals irritate surrounding nerve endings causing localised pain
- restricts movement of site of injury promoting faster repair
7
Q
Explain why loss of function is sometimes classed as a cardinal signs
A
- swelling and pain inhibit movement
- limiting forces injured site to rest promoting healing
8
Q
State the inflammatory mediators (chemicals)
A
- Chemokines
- Bradykinin
- Histamine
- prostaglandins
9
Q
What is a mast cell?
A
Cells releasing chemicals to initiate the inflammatory process
10
Q
What does histamine do?
A
- Granules of mast cells and basophils
- respond to mechanical injury and presence of certain microorganisms and chemicals released by neutrophils
- Promotes vasodilation of local arterioles – **increasing permeability **of local capillaries and promoting exudate (blood plasma) formation – entering tissue casing local oedema
- Also **activate pain receptors **casing itchy sensation
11
Q
What do chemokines do?
A
- Releasing active kinin peptides
- Induces chemotaxis of leukocytes to prompt neutrophils to release lysosomal enzymes to enhance more kinins and induce pain
- Attract neutrophils to the site if injury
12
Q
What do bradykinin do?
A
- Released from blood plasma entering interstitial space
- **Causing vasodilation, increased capillary permeability, activated and sensitise local pain recpetors
- Prolonged release can lead to severe pain
13
Q
What makes histamine?
A
- Granules of mast cells and basophils
14
Q
What makes chemokines?
A
- Plasma protein cleaved by enzyme kallikrein and lysosomes of neutrophils
15
Q
How are bradykinin’s made?
A
- Released from blood plasma entering interstitial space
16
Q
How do you make prostaglandins?
A
- Fatty acids produced from **arachidonic acid **in cell membranes generated by enzymes of neutrophils, basophils, mast cells and others
17
Q
What are prostaglandins?
A
- Released by mast cells
- Induce neutrophil chemotaxis inducing pain
- Activate and sensitise local pain recpetors
- Causing vasodilation and increased blood vessel permeability
- Prolonged release leads to severe pain
18
Q
What is a platelet-derived growth factor (PDGF)?
A
- Secreted by platelets and endothelial cells
- Stimulating fibroblast activity and repair of damaged tissues
19
Q
What is a phagocyte?
A
Floor area after inflammatory process begins
- Starting phagocytosis – gobble unwanted bacteria
20
Q
Why is the inflammatory response important? What does it remove?
A
- Toxins
- Bacteria
- Viruses
- Allergies
- Stress
- Foods (fried, sugary, carbohydrates)
- Physical harm
21
Q
Whats the process of the inflammatory response?
A
- White blood cells release histamine opening capillaries
- blood plasma enter physically slowing foreign invaders entering (swelling)
- other white blood cells release cytokines signalling **more white blood cells to the area ** - phagocytosis occurs
22
Q
What are the negative types of inflammation?
A
- chronic inflammation (long term)
- Can be due to an autoimmune disorder – where immune system attacks healthy tissue
- Osteoarthritis and rheumatoid arthritis
23
Q
What is pus?
A
- Mixture of dead or dying neutrophils, **dead tissue cells and living and dead pathogens **and is creamy-yellow in colour
24
Q
What is vasodilation?
A
- Increased diameter of blood vessel increasing blood volume – causing redness and heat
- Local capillaries becoming leaky – causing swelling
25
What is oedema?
- **Build-up of fluids in body causing swelling**
- As interstitial fluid exudes from capillary tissues become swollen (oedema)
26
What is endothelium?
- thin membrane lining inside of the heart and blood vessels
27
What is a monocyte?
- type of white blood cell that **differentiated into populations of macrophages and dendritic cells to regulate cellular homeostasis**
- leave leaky vessels to mature into macrophages
28
What are two types of phagocytes?
1. **neutrophils**
2. **macrophages**
29
What are neutrophils?
- type of **phagocyte**
- attracted to damaged areas by **chemokines**
- phagocytose invading organisms (this helps attract macrophages to the area)
- **leave leaky capillaries by diapedesis or emigration and move by chemotaxis **
- associated with acute inflammation
30
Whar are macrophages?
- mature version of monocytes
- **tissue healing, defending and cleaning up damaged tissues
- phagocytic **
- associated with chronic inflammation
- in large numbers it can also damage host tissue as phagocytic
31
What is the complement system?
1. **Chemical precursors converted to active complement molecules** when leaving leaky capillaries and interact with invading organisms like bacteria
2. Components **damage bacterial cell membrane **causing their death
3. Also help **make phagocytic cells **such as neutrophils more **effective**
32
What do fibroblasts do for tissue repair after inflammation?
- Fibroblasts **proliferate** and start to **produce collagen fibres to stabilise and close the wound**
33
Define chronic inflammation
- **Prolonged tissue response** lasting from weeks or months where **inflammation, tissue necrosis and tissue repair processes occur simultaneously**
34
What are the causes of chronic inflammation?
1. Persistent infection e.g., Resistant pathogen to human immune system
2. Chronic irritation due to prolonged exposure to toxic agents
3. Repeated episodes of acute
4. Immune mediated inflammatory disease such as rheumatoid arthritis or allergies
35
What do fibroblasts do in chronic inflammation?
- Involved in **healing**
- Once macrophages are activated, they release local growth factors to activate fibroblasts, so they **start repairing basic structures of damaged tissue.**
36
What is the chronic positive feedback loop of inflammation?
- **Macrophages signals leukocytes** (a white blood cell) which **releases an antibody to help **
- Although this also **releases chemicals** that further **activate and stimulate macrophage activity**
