Inflammation and Mediators

Question 1

ER

Answer 1

Site where proteins are synthesized

Question 2

Golgi

Answer 2

Site where secreted proteins are converted to their final forms and packaged for secretion

Question 3

What is the structural basis of TLR?

Answer 3

Multiple extracellular leucine rich modules

Question 4

What is the connection between macrophages and CRP?

Answer 4

Macrophages secrete IL-6–> induces synthesis of fibrinogen by hepatocytes–> activates Jak kinas–> increase in CRP

Question 5

Fc receptors

Answer 5

Bind IgG and enhance phagocytosis

Question 6

How is nitric oxide made

Answer 6

INOS catalyzes the conversion of arginine to citrulline

Question 7

Elastase

Answer 7

• One of the most important enzymes in neutrophils
• Broad spectrum serine protease
• Required for killing many types of bacteria

Question 8

What do Natural Killer cells express?

Answer 8

CD16 (Fc receptor for IgG) and CD56

Question 9

What types of cells do NK cells recognize?

Answer 9

• cells coated with Fc IgG
• Cells infected with viruses
• cells lacking MHC class I (tumor)

Question 10

Classical pathway

Answer 10

• Antibody dependent
• Plasma protein C1q detects antibodies bound to surface of microbe or another structure
• Once C1q binds to the Fc portion, two associated serine proteases, C1r and C1s become active and initiate a proteolytic cascade

Question 11

Alternative pathway

Answer 11

• Not antibody mediated

- Triggered when C3 recognizes certain microbial structures such as bacterial LPS, leading to cleavage to C3b and C3a

Question 12

Which complement components lead to increased vascular permeability?

Answer 12

• C3a and C5a

Question 13

Which complement component has chemotactic ability?

Answer 13

• C5a

Question 14

Which complement can opsonize?

Answer 14

• C3a

Question 15

How does the MAC complex become formed?

Answer 15

• C5b binds C6 and C7
• They become a high affinity receptor for C8
• C9 binds to C5b-8 to form the fully active MAC
• MAC forms pores in plasma membranes in cells its deposited on–> entry of water–> osmotic swelling and cell rupture

Question 16

• Expressed on bone marrow derived cells
• Promotes phagocytosis of C3b and C4b opsonized particles
• On erythrocytes, binds circulating immune complexes and transports them to liver and spleen

Answer 16

• Type I complement receptor CR1/CD35

Question 17

• Stimulates humoral immune response by enhancing B cell activation by antigen and promoting trapping of antigen-antibody complexes in germinal centers

Answer 17

• Type 2 Complement receptor CR2/CD21

Question 18

• Integrin expressed on neutrophils, mononuclear phagocytes, mast cells and Nk
• Promotes phagocytosis
• Also binds to ICAM1 on endothelial cells–> leukocyte migration

Answer 18

Type 3 CR

CR3/Mac-1, CD11bCD18

Question 19

Similar to Type 3

Found on DCs

Answer 19

CR4, p150, 95, CD11C, CD18

Question 20

Expressed on liver macrophages

Involved in clearance of opsonized bacteria and other blood borne pathogens

Answer 20

CRIg

Question 21

Produced by monocytes and macrophages upon stimulation with IFN g

Answer 21

• Marker of Th1 derived immune activation

Question 22

Pentraxins

Answer 22

CRP

SAA

Question 23

IL-2

Answer 23

• Source is T cells
• Growth factor for antigen stimulated T cells
• Can also lead to proliferation and activation of NK cells

Question 24

iL-4

Answer 24

Inhibition of macrophage activation

Question 25

IL-10

Answer 25

- Inhibits production of IL12 and TNF by activated macrophages - Inhibits expression of co stimulators and MHC class II molecules on macrophages

Question 26

IL-12

Answer 26

- Has both innate and adaptive functions - Mediator of early innate immune response to intracelluar microbes - Produced in response to TLR - Stimulates interferon gamma production by NK cells - Stimulates diff of CD4 helper into Th1 - Stimulates CD8 to CTL - Stimulates IFNG production by T cells

Question 27

Phospholipase A2

Answer 27

Produces arachidonic acid

Question 28

What are the three major metabolites from Arachidonic acid ?

Answer 28

COX--> Prostagladins, thromboxane | LOX--> Leukotrienes

Question 29

Inhibits the action of phospholipase 2

Answer 29

Steroids

Question 30

Which COX is inducible enzyme during inflammation?

Answer 30

COX 2

Question 31

How to NSAIDs cause ulcers

Answer 31

block Cox --> decreased Prostaglandins--> increased stomach acid, decreased mucous secretion

Question 32

Mediate bronchoconstriction and vasoconstriction

Answer 32

Leukotrienes

Question 33

What induces MHC class II on macrophages

Answer 33

- IFN gamma

Question 34

Proteolytic fragment of C2

Answer 34

Kinin