Alternative pathway Flashcards
1
Q
What does alternative pathway bypass
A
bypasses C1, C2 and C4
2
Q
what is the C3 convertase and C5 convertase for this pathway
A
C3 convertase is C3bBb
C5 convertase is C3bBb3b
3
Q
describe C3 tickover for alternative pathway
A
is a soluble C3 convertase with an active site for factor B
formed via hydrolysis and this reaction is slow
its C3 convertase is C3(H2O)Bb
4
Q
how does amplification loop form
A
formed when more and more C3b is formed
5
Q
what is the function of properdin in alternative pathway
A
properdin stabilises C3 convertase and promotes the dissociation of factor B with C3b
6
Q
function of factor H
what does factor H deficiency cause
effect of anionic surface
A
it is the regulator for alternative pathway needs cofactor factor I competes with C3b for binding site Deficiency: reduction in C5 convertase Anionic surface encourages factor H
