Week 9 Flashcards
whats the difference between innate and acquired immunity?
Innate - doesnt require previous exposure to invading microbe
Acquired - the system remembers how to deal with a microbe it’s health with before
How does innate immunity work/
- Neutrophils eat pathogen and send distress signal
- Monocytes are triggered to turn into pathogen-eating macrophages
- Eosinophils attack parasites
- Basophils contain granules filled with histamine and other compounds
what is the primary physicall effects of the inflammatory response
- Blood vessels dilate -> increasing blood flow
- capillary wall permeability
- red and warm due to increased blood flow
- swollen tissues due to increased blood and proteins
- painful due to pressure on nerve cells and due to the presence of pain mediators
WHat are the characteristics of inflammation?
pain
heat
redness
swelling
WHat is the purpose of nomal imfglammatory response?
protective response to eliminate initial cause of injury (bacteria/toxins) and consequences of injury such as dead cells and tissues
WHat is a mast cell?
- Mast Cells are one of the primary facilitators of both inflammatory and immune responses.
• When Mast cells are damaged (or activated by antigens) they release their contents into the interstitial fluid.
what does a mast cell release?
• Mast Cells degranulation releases: – Histamine – Neutrophil chemotactic factor – Eosinophil chemotactic factor – and produces: o Leukotrienes o Prostaglandins
WHat does Histamine do?
Histamine is a vasoactive amine. It:
• Temporarily and rapidly vasoconstrictor large vessels
• Vasodilates post capillary venules
• Retracts the endothelial cells of the capillary walls.
Chemotactic factors attract WBC to destroy dead tissue and toxins, but importantly they release substances (histaminease) that limit the runaway effect of histamine.
What are Leukotrienes?
Slow‐reacting substances of anaphylaxis (SRS‐A)
• Similar effects to histamine (increased vascular permeability, WBC chemotactic)
• Stimulate slower but longer response than histamine
what are prostaglandins?
- Synthesised in several forms (E, A, F, B).
- Type E associated with inflammation
- Act on smooth muscle (esp. post capillary venules)
- Increase vascular permeability
- Suppresses histamine release
- Responsible for the long‐term pain of inflammation
- Aspirin and some NSAIDs supresses PG‐E synthesis.
What is an antigen?
– Any substance that when introduced
into the tissues or blood induces the
formation of antibodies and reacts
only with its specific antibodies.
What is an antibody?
– A protein produced by certain cells in the body in the presence of a specific antigen; the antibody combines with that antigen to neutralise, inhibit or destroy it.
what is an allergen?
– An antigen that provokes a hypersensitivity reaction
Define anaphylaxis?
is a severe, life-threatening, generalised or systemic hypersensitivity reaction,
characterised by rapidly developing life-threatening airway and/or breathing
and/or circulation problems usually associated with skin and mucosal changes
What are the mechanisms of anaphylaxis?
• Prior sensitisation to an allergen
• Interaction of an allergen with specific immunoglobin (IgE) antibodies
• Leads to activation of mast cells and release of preformed mediators stored in granules
• Mediators cause capillary leakage
and mucosal oedema resulting in shock and asphyxia
