Hunter: Acute Phase Response

Question 1

Most responses to pathogens remain (blank), but systemic responses do occur

Answer 1

localized

Question 2

Some systemic inflammatory responses to pathogens can be positive and protective. Give an example; other systemic responses can be negative and harmful. Give an example

Answer 2

acute phase response and fever; sepsis and septic shock

Question 3

What is the LPS receptor?

Answer 3

CD14

Question 4

Cytokines that mediate the acute phase response and fever

Answer 4

IL-6, TNF-alpha, IL-IB

Question 5

Chemotactic factor that recruits neutrophils and basophils to the site of infection

Answer 5

CXCL8

Question 6

This cytokine is predominantly involved in the acute phase response in the liver

Answer 6

IL-6

Question 7

Cytokines involved in induction of fever

Answer 7

IL-1 and TNF-alpha

Question 8

These are the principle cytokines that mediate the systemic effects of inflammation

Answer 8

IL1
IL6
TNF-alpha

Question 9

an evolutionarily conserved and highly coordinated systemic reaction to disturbances in homeostasis caused by infection, tissue injury, trauma or surgery, neoplastic growth, or immunological disorders

Answer 9

acute phase response

Question 10

The acute phase response involves changes in plasma levels of (blank), many produced in the liver in response to (blank)

Answer 10

acute phase proteins *fibrinogen, haptoglobin, serum amyloid protein, C-reactive protein;
IL6

Question 11

the predominant cytokine produced during an inflammatory response that induces the liver to produce acute phase reactants like C-reactive protein

Answer 11

IL-6

Question 12

Positive acute phase proteins include:
(blank), which opsonizes and traps microorganisms
(blank) which activates complement
(blank) which causes coagulation and fibrinolysis,
(blank) which scavenges free Hg and iron,
and (blank) which neutralizes enzymes

Answer 12

C-reactive protein;
Mannan-binding lectin;
Fibrinogen, prothrombin, factor VIII;
ferritin;
alpha 1-antitrypsin

Question 13

What does C-reactive protein do?

Answer 13

good diagnostic marker of inflammation

also promotes opsonization by activating the classical complement pathway and generating c3b

Question 14

an acute phase protein produced in the liver that functions as an opsonin to promote the phagocytosis and killing of this microorganism

Answer 14

C-reactive protein

Question 15

Inflammation-associated coagulation begins when cytokines, Toll-like receptor (TLR) agonists, or other stimuli induce (blank) expression on the surfaces of monocytes and vascular endothelial cells

Answer 15

tissue factor

Question 16

hepatic synthesis of these two factors decreases during the acute-phase response

Answer 16

protein C

antithrombin III

Question 17

The end result of the acute phase reaction is increased (blank) activity and decreased (blank), which promotes fibrin formation and thrombosis

Answer 17

thrombin; fibrinolysis

Question 18

Local infection causes release of cytokines which communicate with brain centers to affect local cytokine and prostaglandin synthesis and produce (blank) and (blank)

Answer 18

sickness behavior;

fever

Question 19

What are some ways in which the acute phase response is kept in check

Answer 19

anti-inflammatory molecules:
IL-1 receptor antagonists
neuroendocrine hormones to downregulate immune responses
protease inhibitors or antioxidants

Question 20

Body temperature is a vital sign that is controlled by the (blank)

Answer 20

hypothalamus

Question 21

Neurons in the hypothalamus receive two kinds of signals in order to maintain the hypothalamic set point

Answer 21

1. signals from peripheral nerves about warmth/cold receptors in the skin
2. signals about the temperature of the blood

Question 22

What is fever?

Answer 22

increase in the hypothalamic set point due to the generation of prostaglandins, leading to an elevation of normal body temperature

Question 23

What is the first sign of fever?

Answer 23

vasoconstriction in hands and feet, which shunts blood away from periphery to internal organs and makes you feel cold - shivering may occur to generate heat

Question 24

T/F: For most fevers caused by infections, body temperature only increases by 1°-2°C

Answer 24

True

Question 25

any substance that causes fever

Answer 25

pyrogen

Question 26

Name one exogenous pyrogen - substance outside the patient that causes fever

Answer 26

LPS endotoxin produced by all gram-negative bacteria

Question 27

Endotoxins from bacteria can directly cause fever, but fever can also be caused indirectly through what mechanism?

Answer 27

release of cytokines, like IL1, IL6 and TNFalpha

Question 28

T/F: Fever is always due to microbial agents.

Answer 28

False; fever can be a manifestation of disease due to inflammation, trauma, tissue necrosis, antigen-antibody complexes; it can even be due to unknown origin

Question 29

key arachidonic acid metabolite responsible for resetting of the hypothalamic set point

Answer 29

PGE2

Question 30

What must you lower in order to lower fever?

Answer 30

PGE2

Question 31

Which enzyme is inhibited by acetaminophen, aspirin, and other non-steroidal anti-inflammatory drugs?

Answer 31

cyclooxygenase

Question 32

What are some benefits of fever?

Answer 32

many microorganisms grow best w/i a narrow temp range, so hyperthermia benefits the patient;
increases antibody production;

Question 33

What are some down-sides to fever?

Answer 33

very high temps are harmful;
high rectal temp is called (hyperpyrexia);
heat stroke