Inflammation Flashcards
What are the 4 classical descriptions of inflammation?
Rubor, tumor, calor and dolor (redness, swelling, heat and pain respectively).
What is cellulitis?
List 2 common causes.
- Acute skin infection.
- Commonly caused by:
1 - Streptococcus pyogenes.
2 - Staphylococcus aureus.
What is the function of inflammation?
To destroy, dilute or wall off an injurious agent and induce repair.
List 6 components of barrier immunity.
Physical barriers:
1 - Skin.
2 - Lungs.
3 - Gut.
Active barriers:
4 - Cilia.
5 - Secretions.
6 - Antibacterial peptides.
Give an overview of the acute phase response of the innate immune system.
1 - Recognition of the danger signal by innate immune cells.
2 - Response mediated by:
- Cellular activation.
- Cellular recruitment.
- Cytokine activation.
- Complement activation.
3 - Destruction of the pathogen and resolution of inflammation or recruitment of adaptive immune response.
How are threats recognised by the innate immune system?
Via pattern recognition receptors (especially on mast cells, however pattern recognition receptors are present on every innate immune cell).
List 3 functions of mast cells.
1 - To detect injuries via pattern recognition receptors.
2 - To release histamine and other mediators.
3 - To initiate the inflammatory response.
List 3 functions of histamine.
1 - To cause vasodilation.
2 - To widen the endothelial junction, increasing permeability.
3 - To cause irritation of nerve endings, causing itching and pain.
List 2 mediators of inflammation.
1 - Histamine.
2 - Arachidonic acid metabolites (eicosanoids).
List 3 eicosanoids that mediate inflammation.
Through which pathways are they produced?
Through the COX pathway:
1 - Prostaglandins.
2 - Thromboxane.
Through the lipoxygenase pathway:
3 - Leukotrienes.
List 2 effects of COX pathway products.
1 - Vasodilation.
2 - Prolongation of oedema.
List 4 effects of leukotrienes.
1 - Vasoconstriction.
2 - Chemotaxis.
3 - Increase vascular permeability.
4 - Bronchospasm.
What is montelukast?
A leukotriene receptor antagonist used in asthma.
List 2 drugs that block the COX pathway.
1 - Aspirin.
2 - NSAIDs.
Give an example of a use of prostaglandins.
Prostaglandins are used to treat pulmonary hypertension.
How do nonsteroidal anti-inflammatory drugs (NSAIDs) prevent inflammation?
By blocking the COX pathway.
What is the cause of erythema?
Vasodilation.
What is the cause of oedema?
Increased vascular permeability.
Which type of proteins are the cause of localised heat during inflammation?
Cytokines.
List 2 advantages of vasodilation during inflammation.
1 - Increases blood flow and pooling, increasing migration of activated cells to the tissues.
2 - Increases local temperature.
What is the advantage of increased endothelial permeability during inflammation?
The fluid loss into tissue leads to concentration and stasis of red blood cells in local vessels.
Why is blood stasis advantageous during inflammation?
Because blood stasis contributes towards the migration of immune cells towards the offending agent.
List 3 acute phase cytokines.
1 - IL-1.
2 - TNF-alpha.
3 - IL-6.
List 6 responses of the body to acute phase cytokines.
1 - The endothelium vasodilates and increases permeability.
2 - The hypothalamus increases the ‘set’ temperature.
3 - Fat and muscle increase mobilisation of energy stores.
4 - The liver increases production of acute phase proteins such as C-reactive protein (CRP).
5 - The bone marrow increases mobilisation of neutrophils.
6 - Dendritic cells release tumour necrosis factor, which stimulates maturation and migration to lymph nodes (initiates the adaptive immune response).
