Complement Cascade

Question 1

What activates the classical pathway of complement?

Answer 1

IgG and IgM

Question 2

In the classical pathway, ow are complement factors bound?

Answer 2

In numerical order, except at the beginning (C1, C4, C2, C3… etc)

Question 3

In classical pathway, “a” fragments go into ____?
And “b” fragments attach to _____?
What is the exception?

Answer 3

“a” fragments go into plasma
“b” fragments attach to cell
exceptions: C2a and c2b

Question 4

What is the alternative pathway activated by?

Answer 4

Lipopolysaccharides and polysaccharides

Question 5

What do the polysaccharides activate in the alternative pathway?

Answer 5

C3

Question 6

What other factors are involved in the alternative pathway?

Answer 6

Factor B and D, and control factors H & I

Question 7

What two ions are required for the complement cascade?

Answer 7

Calcium and magnesium

Question 8

What is the role of complement?

Answer 8

Activates phagocytes
Lyses target cell (foreign organism)
Opsonizes – enhances phagocytic binding by coating foreign organism