Innate Immune System Flashcards
What is the immune system?
Cells and organs that contribute to immune defences against infections and non-infectious conditions
What is an infectious disease?
When a pathogen succeeds in evading and/or overwhelming the host’s immune defences
What are the roles of the immune system?
Pathogen recognition
Containng/Eliminating the infection
Regulating itself
Remembering pathogens
Decribe the differences between innate and adaptive immunity
Innate provides immediate protection that is rapid but lacks specificity, memory and has no change in intensity to the response to the pathogen
Adaptive provides long lasting protection that is specific, changes intensity depending on pathogen and has immunological memory, however it is a slow process
What are the lines of defence of Innate immunity
First Line:
- Physical barriers
- Physiological barriers
- Chemical barriers
- Biological barriers
Second Line:
- Phagocytes
- Chemicals
- Inflammation
Name some antimicrobial molecules that act as a chemical barrier
IgA
Lysozyme
Mucus
Beta-defensins
Gastric acid and pepsin
When might normal flora casuse clinical problems?
Normal flora is displaced from its normal location to a sterile location
Normal flora overgrows and becomes pathogenic when host becomes immuno-compromised
Normal flora is depleted by antibiotics
Name the cells of the innate immune system
Macrophages
Monocytes
Neutrophils
Basophils
Eosinophils
Natural Killer cells
Dendritic cells
How do phagocytes recognise pathogens- what are the structures on the cells
Pathogen-Associated Molecular Patterns (PAMPs)
Pathogen Recognition Receptors (PRRs)- Toll Like Receptors (TLR)
Name some Opsonins
Complement proteins: C3b and C4b
Antibodies: IgG and IgM
Acute phase proteins: CRP and Mannose-Binding Lectin (MBL)
