4- Innate Immunity- Inflammation

Question 1

What is inflammation?

Answer 1

Tissue reaction that rapidly delivers mediators of host defense to the sites of infection and tissue damage

Question 2

What are the three essential roles that inflammation plays in combating infection?

Answer 2

1) Deliver additional effector molecules and cells to the sites of infection to augment the killing of invading microbes by the front-line macrophages
2) Provide a physical barrier preventing the spread of infection
3) Promote the repair of injured tissue

Question 3

What are the cardinal signs of an inflammatory response?

Answer 3

Pain, redness, heat, and swelling

Question 4

What causes redness at the site of an injury?

Answer 4

Increased blood flow to that area

Question 5

What causes swelling (edema) at the site of an injury?

Answer 5

Increased extravascular fluid and phagocyte infiltration to the damaged area

Question 6

What causes heat at the site of an injury?

Answer 6

increased blood flow and the action of pyrogens (fever-inducing agents)

Question 7

What causes pain at the site of an injury?

Answer 7

local tissue destruction and irritation of sensory nerve receptors

Question 8

List the pro-inflammatory mediators

Answer 8

-cytokines
-chemokines
- vasoactive amines
- vasoactive peptides
- vasoactive lipids
- coagulation system

Question 9

What are cytokines?

Answer 9

When exposed to infectious agents or their PAMPs, sentinel cells sythesize and secrete three major cytokines
- tumor necrosis factor-alpha (TNF-alpha)
- Interleukin-1 (IL-1)
- Interleukin-6 (IL-6)

Question 10

What are the clinical signs and effects of proinflammatory cytokines in low quantities?

Answer 10

local inflammation, which indices macrophage activation, endothelium activation, complement activation

Question 11

What are the clinical signs and effects of proinflammatory cytokines in moderate quantities?

Answer 11

local systemic effects, including fever, lethargy, loss of appetite from effects of hypothalamus, production of acute-phase proteins from actions on the liver, and neutrophilia resulting from action on bone marrow

Question 12

What are the clinical signs and effects of proinflammatory cytokines in high quantities?

Answer 12

systemic vasodilation, increased vascular permeability.
This leads to a drop in blood pressure and low cardiac output, vascular injury, thrombosis and disseminated intravascular coagulopathy (DIC), pulmonary edema, air spaces filled with fluid, and leads to acute respiratory distress syndrome (ARDS)