1	One Step Further Complement Activation OSF - 6 Pages 84 - 86
2	Complement Activation - 2 Two enzymatic pathways available: eClassical pathway eAlternative pathway Žfirst one discovered Žactivated by immune complexes Žactivated primarily by polysaccharide structures microbial cell walls is an example Two enzymatic pathways join at: eClevage of C5 which results in: Žformation of the Membrane Attack Complex (MAC) this results in lysis of cell
3	Complement Activation - 3 Classical pathway activation: ethe sequence of activation is: Immune complex \ C1q of C1 complex \ C4 - C4a \ C4b \ C2 - C2a \ C2b C4b \ C2b - C3 convertase C3 convertase \ C3 - C3b C3b \ C3 convertase - C5 convertase C5 convertase \ C5 - C5b C5b \ C6 \ C7 \ C8 \ C9 MAC cell lysis
4	Complement Activation - 4 Alternative pathway activation: ethe sequence of activation is: C3 - C3b (C3b is found normally in the blood due to hydrolysis of C3) C3b - binds to microbial surface C3b \ Factor D \ Factor B - C3 convertase C3 convertase \ C3 - C3b C3b \ C3 convertase - C5 convertase C5 convertase \ C5 - C5b C5b \ C6 \ \ \ C7 C8 C9 MAC cell lysis
5	Complement Activation - 5 Regulation of pathways: eC1 INH eFactor I eFactor H eC4bp Žinhibits C1 binding with immune complex Žinhibits C3b Žinhibits C3 convertase formation Žinhibits C3b + Factor B & Factor D interaction Žinhibits C3 convertase formation Žbinds with C4 Žinhibits C3 convertase formation
6	Complement Activation - 6