IM3: Understanding Inflammation Flashcards
What are the 4 cardinal features of inflammation?
- Heat
- Redness
- Swelling
- Pain
What causes the cardinal feature of heat in inflammation?
Increased blood flow and release of inflammatory mediators
What causes the cardinal feature of redness in inflammation?
Increased vascularity of the region
What causes the cardinal feature of swelling in inflammation?
Exudation of fluid, proteins and cells into the area of tissue damage
What causes the cardinal feature of pain in inflammation?
Caused by activation of pain receptors by inflammatory mediators in inflammatory exudate
How may inflammation be triggered? (5)
Give an example of each of these triggers
- Physical agents (heat)
- Foreign bodies (splinter)
- Chemicals (acid)
- Infections (bacteria)
- Immune mediated (immune complexes)
What are the main functions of inflammation? (3)
- Destroy and remove pathogens or injuring foreign bodies
- Limiting and confining the effects of pathogens and their products
- Repairing and replacing damaged tissue
What is acute inflammation?
What is it characterised by?
- Occurs early and consists of transient episodes (days, weeks)
- Characterised by neutrophil infiltration
What is chronic inflammation?
What is it characterised by?
- Long lasting inflammation (months or years)
- Characterised by lymphocytes and macrophages
What are PAMPs?
Pathogen-associated
molecular patterns
What are PRRs?
Pattern-recognition receptors
Explain the relationship between PAMPs and PRRs during inflammation
PAMPs are found on the surface of the microbe. These PAMPs are then recognised by PRRs.
A inflammatory response is then triggered by this
What are the 3 types of granules that are expressed by platelets?
- Αlpha
- Dense
- Lysosomal
Which platelet granule reaches;
- Chemokines
- Coagulation factors
- Growth factors
- Fibrinogen
- Fibronectin
Alpha granule
Which platelet granule reaches;
- Ca2+
- Mg2+
- Nucleotides
- Serotonin
- Histamine
Dense granule
Which platelet granule reaches;
- Proteases
- Collagenase
Lysosomal granule
What is the role of platelets in inflammation? (4)
- Block spread on infection by clot formation
- Induction of pro-inflammatory cytokines
- Breakdown of microbes by lysosome granules
- Contribute to engulfing of bacteria
What do mast cells promote in inflammation? (3)
- Vasodilation
- Vascular constriction
- Delivery of plasma/cells to injured area
What is the role of neutrophils in inflammation?
Neutrophils kill and degrade pathogens
What is leukocyte extravasation?
The movement of leukocytes out of the circulatory system and towards the site of tissue damage or infection
What molecules aid leukocyte extravasation? (3)
- Integrin
- P-selectin
- E-selectin
What occurs to leukocytes and neutrophils in leukocyte adhesion deficiencies? (3)
- Leukocyte unable to leave the circulatory system
- Neutrophil unable to aggregate
- Neutrophil counts are twice the normal level
Explain the events of leukocyte extravasation
- Chemokines are released by immune cells at site of injury
- This activates endothelial cells to present adhesion molecules
- Receptors on the neutrophil adhere to these molecules and begin to roll along the vessel
- Eventually rolling stops and neutrophil exists the vessel (diapedesis)
Explain the process of phagocytosis
- Chemotaxis and adherence of microbe the phagocyte
- Ingestion of microbe by phagocyte
- Formation of phagosome
- Fusion of the phagosome with a lysosome
- Digestion of ingested microbe by enzymes
- Formation of residual body containing ingestible materials
- Discharge of waste materials
What is the role of M1 Macrophages? (2)
- Microbicidal actions
- Pathological inflammation
What is the role of M2 Macrophages? (2)
- Anti-inflammatory effects
- Wound repair and fibrosis
What are the local effects of IL-1? (2)
- Inflammation
- Reapir
What is the systemic effect of IL-1?
Systemic manifestations of inflammation
Give 2 examples of anti-inflammatory cytokines and what do they do?
- TGF-beta
- IL-10
- Inhibit secretion of pro-inflammatory cytokines
What is type I hypersensitivity mechanism?
An example of when this mechanism occurs?
- IgE-Mediated hypersensitivity
- Hay fever
- Food allergy
What is type II hypersensitivity mechanism?
An example of when this mechanism occurs?
- IgG-Mediated cytotoxic hypersensitivity
- Hemolytic disease
- RBC destruction
What is type III hypersensitivity mechanism?
An example of when this mechanism occurs?
- Immune complex mediated hypersensitivity
- Glomerulonephritis
What is type IV hypersensitivity mechanism?
An example of when this mechanism occurs?
- Cell-mediated hypersensitivity
- Dermatitis
- T1 Diabetes
- Multiple sclerosis
