the complement Flashcards
1
Q
what is the complement
A
the humoral part of the innate immune system
2
Q
what does the complement do
A
it stimulates inflammation, it destroys cells and is part of opsonisation
3
Q
what can the complement be activated by
A
the classical and alternative pathway
4
Q
what components are part of the complement
A
many foreign, soluble, serum proteins C1-C9
5
Q
what are the three pathways
A
classical, alternative and lectin pathways
6
Q
describe the classical pathway
A
- C1 becomes activated when binds to a antigen-antibody complex
- C1 then cleaves C2 into C2a and b and cleaves C4 into C4a and b
- C2b and C4b react to form C3 convertase
- C3 convertase then cleaves C3 to form C3a and b
7
Q
describe the alternative pathway
A
- endotoxin polysaccharides or cell wall components bind to C3b
- C3a and b are always being made from C3 but if no activation occurs then they will be destroyed
- when C3b binds to endotoxin polysaccharides they
