Inflammation and Repair

Question 1

Inflammation

Answer 1

protective response of vascularized tissues to infections and damaged tissues

• brings cells & molecules from host defense from circulation to sites where needed
• goal: eliminate offending agent
• damaged tissue is repaired

Question 2

Acute Inflammation

Answer 2

Innate Immunity
onset: minutes-hours
cellular infiltrate: mainly neutrophils
Tissue injury: mild & self limiting
local and systemic signs: prominent

Question 3

Chronic Inflammation

Answer 3

Adaptive Immunity
Onset: slow (days)
Cellular infiltrate: monocytes/macrophage & lymphocytes
tissue injury: severe & progressive
local & systemic signs: less

Question 4

Recognition of ‘Offending’ Agents

Answer 4

TLRs
Sensors of cell damage
other cell receptors
circulating proteins

Question 5

Dendritic Cells

Answer 5

APCs (accessory cells)-process antigen material and present it on the cell surface to the T-cells of the immune system.
-act as messengers between innate and adaptive immunity

Question 6

Langerhans cells

Answer 6

cutaneous dendritic cells

Question 7

Gain of Fxn Mutations

Answer 7

located in sensors
-cause of rare auto-inflammatory syndromes, characterized by spontaneous inflammation
Tx: IL-1 antagonists

Inflammosome-inflammatory rxn to urate crystals, lipids, cholesterol, amyloid deposits

Question 8

Components of Acute Inflammation

Answer 8

1. Dilation of small vessels
2. Increased permeability of the microvasculature allowing plasma proteins to leave circulation
3. emigration of the leukocytes from circulation and accumulation at the point of injury and activation of eliminate the offending agent

Question 9

Histamine

Answer 9

Source: mast cells, basophils, platelets
Action: vasodilation, increased vascular permeability, endothelial activaiton

Question 10

Prostaglandin

Answer 10

Source: Mast cells, leukocytes
Action: vasodilation, pain, fever

Question 11

Leukotrienes

Answer 11

Source: Mast cells, leukocytes
Action: increased vascular permeability, chemotaxis, leukocyte adhesion and activation

Question 12

Cytokines

Answer 12

(TNF, IL-1, IL-6)
Source: macrophages, endothelial cells, mast cells
action: local-endothelial activation
systemic-fever, metabolic abnormalities, hypotension (shock)

Question 13

Chemokines

Answer 13

Source: leukocytes, activated macrophages
action: chemotaxis, leukocyte activation

Question 14

Platelet-Activating Factor

Answer 14

Source: leukocytes, mast cells
Action: vasodilation, increased vascular permeability, leukocyte adhesion, chemotaxis, degranulation, oxidative burst

Question 15

Complement

Answer 15

Source: plasma (produced in liver)
Action: leukocyte chemotaxis and activation, direct target killing (MAC), vasodilation (mast cell stimulation)

Question 16

Kinins

Answer 16

Source: plasma (produced in liver)
Action: increased vascular permeability, smooth muscle contraction, vasodilation, pain

Question 17

TNF & IL-1

Answer 17

act on endothelial cells of post-capillary venules adjacent to the infection and induces expression of adhesion molecules

Question 18

Transmigration/Diapedesis

Answer 18

follows adhesion to endothelium
-leukocyte recruitment & migration thru endothelium
occurs mainly in post-capillary venule
*PECAM-1 (CD-31)

Question 19

Chemotaxis

Answer 19

follows adhesion to endothelium & leukocyte migration

-leukocytes move toward site of injury

Question 20

Exogenous Agents that stimulate inflammation

Answer 20

most commonly bacterial products

peptides that produce *N-fromylmethionine

Question 21

Endogenous Chemoattractants

Answer 21

Chemical mediators

• cytokines (IL-8)
• complement system esp C5a
• arachidonic acid metabolites (leukotriene: LTB4)

Question 22

Integrins

Answer 22

transmembrane adhesive glycoprotein that allows cells to attach to ECM constituents such as laminin & fibronectin

links the intracellular cytoskeleton to outside world

• also triggers signaling cascades for:
• –locomotion
• –proliferation
• –shape
• –differentiation