12a. Immune Health - General Flashcards
What is the role of the immune system?
Identify/neutralise pathogens
Distinguish self vs non-self
Distinguish pathological vs non-harmful antigens
Repair the site of any injury/damage
Tumour surveillance
What are the implications of immune dysfunction?
Increased susceptibility to infection
Increased susceptibility to AI
Allergies and AI (cross-reactivity)
Insufficient repair/scarring/cell damage/ chronic inflammation
Inability to recognise and kill cancer cells
What is the internal threat of an immune over-reaction?
AI condition
What is the internal threat of an immune under-reaction?
Cancer
Re-activated viruses
What is the external threat of an immune over-reaction?
Allergic reactions
Food intolerances
What is the external threat of an immune under-reaction?
Infection
What theory helps explain why some people become ill and others don’t despite same exposure to a pathogen?
Terrain theory
What are the new challenges to our immune system?
Dysfunctional immune programming due to less diverse/early pathogen exposure/compromised gut microbiome
New antigens - exposure to toxins
Reduced resilience due to unhealthy lifestyles
Overuse of antibiotics
What systems is the immune system made up of?
Innate
Acquired/adaptive
What is the innate external immune system made up of?
Skin
Mucous membranes
Sebum
Sweat
Stomach acid
Tears
Mucous/SIgA
Vaginal bacteria
What is the innate internal immune system made up of?
Phagocytes
Basophils/mast cells
Fever
Interferons
Complement system
Natural killer cells
Which immune cells are antigen presenting?
CD4
CD8
Which immune cells make up the acquired/adaptive immune system?
CD4
Th1
Th2
Th17
T-reg
What is effective immunity dependent upon?
Healthy barrier tissue - skin, gut, lungs
Presence of secretions - tears, saliva - with antimicrobial properties
Probiotic bacteria
MALT/GALT secreting SIgA
Leukocytes recognising pathogens via pattern recognition
Inflammation - quarantines particular area
Adaptive immune system
What is the function of Th1 cells?
Defence against intracellular pathogens - viruses
Anti-cancer/tumour
Which cytokine m promotes differentiation of CD4 cells into Th1?
IL-12
What triggers the differentiation of CD4 cells into Th1?
Cytotoxic T-cells
Macrophages
IFN-y
TNF-a/b
What is the function of Th2 cells?
Defence against extracellular pathogens - parasites
Which cytokine is promotes differentiation of CD4 cells into Th2?
IL-2
IL-4
IL-5
What triggers the differentiation of CD4 cells into Th2?
IL-4, 5, 10, 13
B-cell antibody production (IgE)
What is the function of Th17 cells?
Defence against extracellular pathogens
Which cytokine is promotes differentiation of CD4 cells into Th17?
IL-1
IL-6
TGF-b
What triggers the differentiation of CD4 cells into Th17?
IL-6, 17, 22
TNF-a
All involved in the chronic stage of inflammatory diseases inc allergies/AI
What is the function of T-reg cells?
Modulate and deactivate the immune system
