Deck 5: Complement Pathways

Question 1

Amplification steps in the complement pathways occur

A)in the classical pathway with C1 cleaving multiple molecules of C4 and multiple C2 for every C1 and C4; in the alternative pathway with the C3b of other pathways becoming C3 convertase; and then the C3b becoming part of a C5 convertase
B)in all pathways with all the C3 convertases making multiple C3a +C3b
C)with C9 polymerization
D)all of the above
E)A and B only

Answer 1

A and B only

Question 2

Susie has an acute infection-strep throat-and her friend Zoe has a chronic illness, systemic lupus erythematosus.

A)Susie probably has an elevated CH 50 while Zoe probably has a decreased CH50.
B)Susie probably has a decreased CH 50 while Zoe probably has an increased CH50.
C)Both Susie and Zoe probably have an elevated CH 50.
D)Both Susie and Zoe probably have a decreased CH 50.

Answer 2

Susie probably has an elevated CH 50 while Zoe probably has a decreased CH50.

Question 3

Complement has

A)about 9 different proteins that are synthesized by monocytes
B)about 35 different proteins that are synthesized by monocytes
C)about 9 different proteins that are synthesized by monocytes, the liver, macrophages, and epithelial cells
D)about 35 different proteins that are synthesized by monocytes, the liver, macrophages, and epithelial cells

Answer 3

about 35 different proteins that are synthesized by monocytes, the liver, macrophages, and epithelial cells

Question 4

Sometimes a microorganism can directly activate complement through

A)the alternative pathway only
B)the lectin pathway only
C)the alternative and the lectin pathway
D)usually the alternative and the lectin pathways, but with some microorganisms, also the classical pathway

Question 5

Complement proteins are synthesized by

A)the liver
B)monocytes
C)macrophages
D)epithelial cells
E)All of the above

Question 6

What molecule is needed for C1q,r and s to stay together?

A)Mg++
B)Ca++ and Mg++
C)Ca++
D)none of the above

Question 7

Which of the following are anaphylatoxins?

A)C1q, C2a, C4a
B)C2b, C4a, C5a
C)C2a, C4a, C5a
D)C3a, C4a, C5a

Question 8

C1q can

A)bind free-floating IgM that is not bound to antigen
B)become activated after interaction with one surface-bound antibody
C)bind after a conformational change occurs as the result of antigen binding
D)bind IgG4

Question 9

Properdin is a

A)complemencomponent of the classical pathway
B)complement protein of the alternative pathway
C)complement protein of the lectin pathway
D)defensin

Question 10

Anaphylatoxins include

A)C5a
B)C4a
C)C3a
D)C5a and C4a
E)all of the above

Question 11

Inhibitors of complement include

A)factors I, H, and C1INH
B)vitronectin or S protein
C)CR3
D)factors I, H, and C1INH and vitronectin or S protein
E)All of the above

Question 12

The AH50 differs from the CH50 because the AH50

A)measures the alternative pathway and the CH50 measures the classical pathway
B)measures the classical pathway and the CH50 measures the alternative pathway
C)uses rabbit red blood cells and the CH50 uses sheep red blood cells with antibody
D)measures the alternative pathway and the CH50 measures the classical pathway and uses rabbit red blood cells and the CH50 uses sheep red blood cells with antibody
E)measures the classical pathway and the CH50 measures the alternative pathway and uses rabbit red blood cells and the CH50 uses sheep red blood cells with antibody

Question 13

Individual complement components measured with

A)AH50
B)CH50
C)RID
D)bacterial cell lysis

Question 14

Complement can lyse which of the following cells?

A)fungal cells
B)gram-positive bacteria
C)gram-negative bacteria
D)all of the above

Question 15

Which of the following are all opsonic molecules?

A)C3b, C1q, iC3b, C4b
B)C2a, C1q, C3b
C)C2b, C3b, C4b
D)C3b, C4b, C9

Question 16

Complement proteins are involved in all of the following except

A)host defense
B)immune complex clearance
C)interaction with the coagulation pathway
D)lattice formation
E)enhancement of memory

Question 17

The difference in the three pathways is the way the C3 convertase is formed

A)in the classical pathway, the C3 convertase is C1C2; in the alternative pathway, it is C3wBb; and in the MBL pathway, the C3 convertase is C2aC4b
B)in the classical pathway, the C3 convertase is C2aC4b' in the alternative pathway, it is C3wBb; and in the MBL pathway, the C3 convertase is C2aC4b
C)in the classical pathway, the C3 convertase is C1C2; in the alternative pathway, it is C3wBb; and in the MBL pathway, the C3 convertase is MBL-MASP-2
D)in the classical pathway, the C3 convertase is C2aC4b; in the alternative pathway, it is PDBb; and in the MBL pathway, the C3 convertase is C2aC4b

Question 18

Which of the following is correct?

A)C1INH inactivates C1 and inhibits binding of MBL to MASP-2.
B)factor D inhibits factor B and Properdin.
C)DAF inhibits C1q binding to C1r and C1s.
D)CR2 inhibits C3b formation.

Question 19

We would expect that a patient who has chronic liver disease would have complement levels that would be

A)elevated
B)normal
C)decreased
D)indeterminate because there is too little information

Question 20

If the CH50 is lower than normal but the AH50 is normal, which set contains the components that could be involved?

A)factor B, factor D, and Properdin
B)MBL, MASP-1, MASP-2
C)C1, C4, C2, C1INH
D)C5-9

Question 21

Which of the following is an active C3 convertase?

A)C4bC2a
B)C3bC5b
C)C4bC2a.
D)BbDd

Question 22

The factors in the alternative pathway that are involved in the progression of the pathway are_______ and ___________. The factors that are involved in inhibition of the pathway are _____ and _________.

A)Factor C and D , Factor Properdin and Factor I
B)Factor B and D , Factor E and F
C)Factor B and D, Factor ficolin and Factor I
D)Factor B and D, Factor H and I

Question 23

Which pathway(s) can act as a powerful amplifier of the other pathways?

A)the classical pathway
B)the alternative pathway
C)the lectin pathway
D)all of the pathways can amplify each other

Question 24

Complement

A)aids in immune complex clearance
B)interacts with the coagulation pathway
C)can be involved in immune memory enhancement
D)all of the above
E)A and C only

Question 25

To study antibody in a patient's blood in a way that removes the complement,

A)freeze and thaw the serum
B)use serum instead of plasma
C)add LPS and then heat to 100°C for 2 minutes
D)heat the serum to 56^oC for 30 minutes

Question 26

Collectin is

A)another name for the mannose-binding lectin
B)a name for the collective processes involved in all complement pathways
C)a receptor for C3b
D)a receptor for C1q

Question 27

Which of the following has a short half-life unless it lands on the cell surface?

A)C4b
B)C2b
C)C5a
D)C3a

Question 28

MBL binds

A)mannose and MASP-2 become associated and cleave C2 and C4
B)mannose and MASP-1 become associated and cleave C4
C)ficolin and MASP-2 become associated and cleave C2 and C4
D)membranes and MASP-1 become associated and cleave C2 and C4

Question 29

Complement

A)causes lysis of gram-positive cells and has no effect on gram-negative cells
B)causes lysis of gram-negative cells and has no effect on gram-positive cells
C)causes lysis of gram-positive cells and increases the amount of phagocytosis of gram-negative cells
D)causes lysis of gram-negative cells and increases the amount of phagocytosis of gram-positive cells

Question 30

The three different pathways of complement activation are

A)different until the C5 convertase is formed
B)different until the membrane attack complex forms
C)different until activation of C3
D)different until C6 convertase forms

Question 31

Calcium ions are required

A)to keep C4bC2a together
B)to keep C6,7,8 together
C)to allow C9 to polymerize
D)to keep C1q,r,s together

Question 32

C-reactive protein can

A)activate complement in the classical pathway
B)activate complement in the lectin pathway
C)activate complement in the alternative pathway
D)activate complement in the classical pathway and activate complement in the alternative pathway

Question 33

Which is involved in immune complex clearance by phagocytosis or splenic clearance?

A)CR1
B)CR2
C)CR3
D)CR1 and CR3

Question 34

Because a particular antigen is far on the bacteria from another antigen, antibodies binding to these antigens

A)would activate complement only if antibodies bound to them underwent a comformational shift
B)would activate complement only if antibodies bound to them were close enough for the Fc regions of the bound antibodies to bind different globular heads of the C1q molecule
C)would activate complement only if antibodies bound to them underwent a comformational shift and would activate complement only if antibodies bound to them were close enough for the Fc regions of the bound antibodies to bind different globular heads of the C1q molecule
D)none of the above