What are the 3 stages of the innate immunity | Recognition
Activation
Elimination |
What receptors recongise PAMPs and DAMPs and where is it located | Pattern Recognition Receptors are located in
Cytoplasm
Endosomes
Cell membrane |
When PRRs are triggered what is induced | Induce phagocytosis
Induce apoptosis
Inflammatory mediators
Complement proteins
Initiate opsonisation
Secrete inferno cytokine pro cytokines |
What are the 3 transcription factors released by TLR activation | AP-1 --> induces apoptosis
NF-kB --> induces formation of inflammatory cytokines such as TNF-alpha
IRFs --> stimulates production of interferon type I |
What is the corelation between NOD like receptors and gout | Gout is due to the build up of uric crystals, NOD-like receptors will sense this and initiate an inflammatory response leading to the swollen joint appearance |
NLRP-3 activates and what happens | Once it is activated, it oligomerises with an adapter protein and an inactive form of caspase 1 to form an inflammasome which activates IL-1beta which leads to the recruitment leukocytes and induces fever |
What is a antiviral defense | When viral nucleic acid is recongised by the TLR, it leads to the production of type I interferon which leads to the degradation of viral nucliec acid and viral replication and enhances the ability of NK cells |
What are the 3 complement pathways | Classical --> antigen-antibody complexes and certain negatively charged structures
Alternatives --> Activated by several molecules found on microbial surfaces , it spontaneous activation
Mannose -Binding Lectin Pathway --> several carbohydrates found on the microbial surfaces |
What substance do all 3 pathways of the Complement activation lead to | C3 convertase ( C3a and C3b )
C3a is a much more active form compared to C3b which is more of a binding form ( opsonization ). C3b is then converted into C5a/C5b, C5b is then converted into the membrane attack complex. MAC will then insert proteins into the pathogen membrane and cause cell lysis |
Function of the complement system | Opsonisation and phagocytosis --> C3b and C5b bind to the microbes and allow attachment to phagocytes that express C3b receptors
Inflammation --> C5a and C3a attract leukocytes which promotes leukocyte recruitment ( inflammation )
Osmotic lysis --> MAC |
What type of bacteria are resistant to the MAC | Gram positive bacteria resistant to MAC cause of their thick peptidoglycan wall |