Extracellular immunity Flashcards
Immune responses to parasitic infections are mainly … driven
Th2
Where on a parasite should be targetted?
Weak spots e.g. digestive tract
What are the physiological host changes induced by anti-worm immunity?
- Does not kill the worm but makes the GI tract inhospitable for the parasite
- Increased goblet cells resulting in increased mucin secretion, gut motility and water influx into the intestinal lumen
Helminth infections promote the activity of which cells?
Antibodies
Eosinophils
Mast cells
The choice towards a Th2 response is driven by…?
IL-4
Th2 cells promote a strong antibody response based on neutralising which immunoglobulins?
IgG and IgE
What is the role of mast cells in helminth infections?
The are the main effector in helminth immunity
Their surface is loaded with IgE and antigen binding causes mast cell degranulation resulting in inflammation which is damaging to the worms
How do both eosinophils and masts cells have central roles in parasite immunity?
- Both react to antigen complexed IgE and release molecules with potent anti-worm activities.
- Mast cells stimulate worm expulsion
- Eosinophils kill worms
List the different ways helminths can evade vertebrate immunity
- size
- thick extracellular coat
- molecular mimicry
- adsorbing host proteins
- surface antigen shedding
- immunosuppression
- migration
How do Th2 cells promote neutralising antibodies?
- Suppress the action of macrophages
- Promote a strong antibody response based on neutralising IgGs