This is a draft cheat sheet. It is a work in progress and is not finished yet.
Innate immunity
Key points |
Physical |
Secreted |
Cellular |
Born/same |
Skin |
Antibacterial |
Nk cell |
Non specific/fast |
GI tract |
Antibodies |
Phagocytes |
Prevent Pathogen entry |
Respiratory |
Complements |
Induces adaptative |
Mucous |
Cytokines |
Goal 1 - PREVENT
Skin |
Respiratoy |
Eyes |
GI tract |
Dry/Thick |
Tightly Packed |
Blink/Tear |
Peristalsis |
Antimicrobial |
Cilia |
Lysopzyme |
HCl |
Keratin |
Mucus |
Microbial competition |
Low Ph |
Goal 2 - RECOGNISE
PAMP |
Bacteria |
|
PRR |
Highly conserved |
Gram-ve |
Gram+ve |
Collectins |
Only microbes |
LPS |
lipoteichoic Acid |
TLR |
Essential to live |
Lipid A |
|
Nod like |
Effector mechanism
Complements |
Phagocytosis |
NK |
Activation of Adaptive |
Cytokine |
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Stages of Phagocytosis
1 Chemotaxis & Adherence of microbes to phagocytes
2 Ingestion
3 Phagosome formed
4 Phagolysomes through fusion
5 Residual body/ indigestible material formed
6 Discharged waste |
Killing Mechanism
Reactive O2 (Neutrophil) |
After Phagocytosis O2 = Respiratory Burst |
O2 Reduced by NADPH = Hydroxyl radical, hypochlorite |
Reactive N3 (Mcrophage) |
L-arginine L-citruline = NO radicals |
Catalysed by Nitric oxide synthase (iNOS, NOS2), induced by Cytokines and Bac components |
Damage in bacterial DNA and Membrane |
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Complements
Proteins in B (blood) and TF (tissue fluid) |
Via cascade |
C3 convertase activates C3 |
Phagocytosis
Monocytes/ Macrophage |
Neutrophil |
High in GI tract, Lung, Liver, Spleen |
Only in B |
Long life |
Short life |
Cytokines
Protein Messenger |
De/activating |
IL(Interleukin)-1 |
IL-6 |
TNF (tumour necrosis factor) α |
Chemokines |
Chemoattractant |
Inflamation- cell adhere to BV infection site |
IL-8, MCP |
interferons |
IFNα & IFNß Produced by virus infected cell |
Natural killer cell |
Infected/tumour cells |
Respond to TNFa, IL-12 |
make TNFγ |
Upregulate MHC = Activate Macrophage |
IL-12 - differention of CD4 Th1 cell |
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PRR
Collectins
In solution
2 region:
Collagen Like
Interacts with effector
Lectin Like
Interacts with Sugar on pathogen. E.g Mannose
NOD like
In cytoplasm
2 type:
NOD 1
glytamyl diominopimelic
NOD 2
muramyl dipeptide
Gram -ve +ve
TOLL like
TLR 1
G +ve
Lipopeptide
PDG
TLR 2
G +ve
Mycoplasma
TLR 3
RNA virus (ds RNA, Poly:C)
TLR 4
G -ve
LPS
TLR 5
Flagellin
TLR 6
Mycoplasma
TLR 7-8
RNA virus (ss RNA)
TLR 9
Unmenthylated CpG DNA |
Antigen presenting cell
Macrophage |
B-cell |
Mature Dentritic cell (Activate T cell) |
Summary
RECOGNISE PRR/ Complement R
INGEST Phagocytosis/ Opsonisation
RECRUIT Inflammation/ Cytokines
RESPONSE SPECIFIC IL&TNF/ Antigen processing |
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