Inflammatory Mediators

Question 1

CD14

Answer 1

Present on macrophages. Recognizes the PAMP LPR of gram neg bacteria. Co-receptor for TLR

Question 2

NFkappaB

Answer 2

Nuclear transcription factor. Activated when TLR activated and lesads to activation of immune response and production of multiple inflammatory mediators

Question 3

Phospholipase A2

Answer 3

Releases arachidonic acid from the phospholipid cell membrane

Question 4

Prostaglandins

Answer 4

PGI2, PGD2, PGE2 mediate vasodilation and increased vascular permeability

PGE2 mediates pain and fever

Question 5

Leukotrienes

Answer 5

Produced by arachidonic acid metabolism by 5-lipoxygenase

LTB4 attracts and activates neutrophils
LTC4, LTD4, LTE4 mediate vasoconstriction, bronchospasm, increased vascular permeability (slow reactors of anaphylaxis)

Question 6

Four things that activate neutrophils

Answer 6

LTB4, C5a, IL-8, bacterial products

Question 7

Three ways to activate mast cells

Answer 7

Tissue trauma
C3a and C5a
Crosslinking of IgE by antigen

Question 8

HIstamine

Answer 8

Causes vasodilation and increased vascular permeability

Question 9

Actions of mast cells

Answer 9

Immediate response: release of preformed histamine

Delayed response: production of luekotrienes from arachidonic acid maintaining acute inflammation

Question 10

Alternate complement activation pathway

Answer 10

Microbial products directly activate complement

Question 11

Mannose binding lectin pathway for complement

Answer 11

MBL binds mannose on microorganisms activating complement

Question 12

C3a

Answer 12

Triggers mast cell degranulation (anaphylatoxic)

Question 13

C5a

Answer 13

Triggers mast cell degranulation (anaphyatoxic) and chemotactic for neutrophils

Question 14

C3b

Answer 14

opsonin for phagocytosis

Question 15

Hageman factor

Answer 15

Actvated by exposure to subendothelial or tissue collagen. Turns on coagulation and fibrinolytic systems, complement, and kinin system

Question 16

Bradykinin

Answer 16

Mediates vasodilation, increased vascular permeability, pain

Question 17

Pain mediators

Answer 17

Bradykinin and PGE2

Question 18

Mediators of fever

Answer 18

Macrophages release IL-1 and TNF which increase COX activity in perivascular cells of hypothalamus. This increases PGE2, raising temp set point

Question 19

Weibel-Palade bodies

Answer 19

On endothelial cells. Contain von willebrand factor and P-selectin, which is involved in leukocyte rolling

Question 20

Selectins

Answer 20

P-selectin from Weibel-Palade bodies. Released in response to histamine

E-selectin induced by TNF and IL-1

Responsible for leukocyte rolling

Question 21

CD18

Answer 21

Component of integrins. Defective in leukocyte adhesion deficiency. Necessary for leukocyte adhesion to endothelium

Question 22

Opsonins

Answer 22

IgG and C3b

Question 23

Myeloperoxidase

Answer 23

Converts H2O2 to bleach

Question 24

IL-10

Answer 24

Anti-inflammatory cytokine made by macrophages

Question 25

TGF-beta

Answer 25

Anti-inflammatory cytokine made by macrophages

Question 26

IFN gamma

Answer 26

secreted by Th1 cells. Activates macrophages. Promotes B cell class switching from IgM to IgG, promotes Th1 over Th2 phenotype

Question 27

Th2 cell secretions

Answer 27

IL-4: B cell class switching to IgE
IL-5: eosinophil chemotaxis and activation, class switching to IgA
IL-13: similar to IL-4
IL-10: inhibits Th1

Question 28

IL-2

Answer 28

From Th1 cell. Serves as second activation signal for CD8+ activation

Question 29

CD8+ killing

Answer 29

Perforin and granzyme: activate apoptosis

FasL-Fas interaction: activates apoptosis

Question 30

CD40

Answer 30

Receptor on B cells binds to lignand on Th cell providing second activation signal for B cell