Exam 1: Dr. Pruett Chapter 4

Question 1

What is often a problem with Brittany dogs?

Answer 1

Cannot make complement component 3 (C3)

Question 2

What is often a problem that results from not being able to make C3?

Answer 2

It leads to kidney failure and a shorter life span

Question 3

Which pathway(s) require antibody? Which do not?

Answer 3

Classical requires antibody

Lectin and alternative do not

Question 4

What is the general process of the complement pathways?

Answer 4

Starts with an inactive enzyme that becomes activated and cleaves the next enzyme. It is a continuous chain

Question 5

Explain the process of the pathways, specifically, starting with C3 convertase.

Answer 5

C3 convertase cleaves C3 into C3a and C3b. C3b activates C5 convertase, which cleaves C5 into C5a and C5b

Question 6

What is C5b6789 also known as?

Answer 6

The membrane attack complex

Question 7

Since the lectin and alternative pathwways do not use antibody, what do they do?

Answer 7

They use microbes that always exist in the body. They require no contribution from the adaptive/acquired system

Question 8

What does the C1 complex consist of?

Answer 8

C1q, r, and s

Question 9

What is C1q?

Answer 9

The binding component

Question 10

What are C1r and C1s?

Answer 10

Enzymes

Question 11

What does the bindnig of C1q to Ab/Ag complex do?

Answer 11

Activates C1r, which activates C1s, which activates C2 and C4

Question 12

Know and understand the classical pathway (page 57)

Answer 12

Know and understand the classical pathway (page 57)

Question 13

Know and understand the lectin pathway (page 58)

Answer 13

Know and understand the lectin pathway (page 58)

Question 14

Know and understand the alternative pathway (page 59)

Answer 14

Know and understand the alternative pathway (page 59)

Question 15

What does C3 undergo in the alternative pathway?

Answer 15

Spontaneous hydrolysis reaction

Question 16

Describe how the membrane attack complex is formed?

Answer 16

C5b recruits C6 and C7 to the target membrane, forming the complex C5b67
C8 binds to the C5b67 complex, unfolding a hydrophobic region that wedges into the target membrane
Recruit and insert 10-16 copies of C9 into the membrane to create a cylindrical pore

Question 17

Describe what the membrane attack complex does?

Answer 17

MAC breaches the cell membrane of the microbes allowing water to rush in to the cell
Osmotic lysis of the microbe by sufficient number of MAC in the membrane

Question 18

What are different outcomes of complement activation?

Answer 18

Direct target lysis
Tissue inflammation
Endothelial activation
Chemotaxis
Leukocyte activation
Opsonization

Question 19

What is the action of direct target lysis?

Answer 19

Osmodysregulation and lysis of target cells

Question 20

What is the action of tissue inflammation?

Answer 20

Activation of mast cell degranulation leading to release of vasoactive amines

Question 21

What is the action of endothelial activation?

Answer 21

Increased expression of adhesion molecules

Question 22

What is the action of chemotaxis?

Answer 22

Promotes migration of neutrophils, eosinophils, and macrophages toward the site of complement activation

Question 23

What is the action of leukocyte activation?

Answer 23

Upregulation of adhesion molecules, phagocytic receptors, and antimicrobial effectors by neutrophils and monocytes

Question 24

What is the action of opsonization?

Answer 24

Enhancement of particle phagocytosis by macrophages and neutrophils

Question 25

What are some of the complement control proteins?

Answer 25

C1 inhibitor
Factor H
Decay-accelerating factor (CD55)
Complement receptor I
Protectin

Question 26

What does C1 inhibitor do?

Answer 26

Inactivates C1r, C1s, and MASPs

Question 27

What does factor H do?

Answer 27

Binds C3b and accelerates decay

Question 28

What does decay-accelerating factor (CD55) do?

Answer 28

Accelerates decay of C3 convertase

Question 29

What does complement receptor I do?

Answer 29

Binds C3b and C4a and inhibits alternative and classical/lectin C3 convertases

Question 30

What does protectin do?

Answer 30

Binds to C5b678 and prevents C9 recruitment and MAC formation

Question 31

What does Louis Pillemer and his team discover?

Answer 31

Properdin

Question 32

What are 2 important points about Pillemer’s resarch?

Answer 32

Attention to detail is critical

Persistence is essential

Question 33

What is C5b678 known as?

Answer 33

Scaffold portion of MAC

Question 34

Which portion of the MAC makes the pore?

Answer 34

C9

Question 35

Which portion of the MAC is hydrophobic and wedges in the membrane?

Answer 35

C8