Inflammation & Repair: body response to injury

Question 1

What are the main components of inflammation (2)?

Answer 1

Vascular changes

Cellular changes

Question 2

Explain the 2 types of vascular changes in inflammation

Answer 2

Hemodynamic changes
-transient vasoC followed by vasoD (via vascular smooth muscle)

It causes hyperemia: increased blood flow

Increased permeability
-mostly venous end of capi
 = leakage of exudate
= increase osmotic pressure
= «         »blood viscosity
= diminution of blood velocity (flow)

Question 3

Increased permeability is d/t what (3)?

Answer 3

Endothelial cell damage

« » contraction

Leakage of new small blood vessels during repair

Question 4

What is exudate

Answer 4

Prot-rich fluid and some blood cells out of the circulation

Question 5

Where mast cells are located?

Answer 5

Around the capillaries

Question 6

Mast cells are a source pf what?

Answer 6

Vascular mediators

Histamine

Question 7

In acute inflammation, mast cells release

Answer 7

Histamine

Question 8

Describe the effect of histamine in the inflammation process

Answer 8

VasoD
Increased permeability of venou capillaries

Responsible for que QUICK/TRANSIENT change in permeability

Question 9

An increased in permeability may be delayed in what case?

Answer 9

Sunburn

Question 10

What are the steps of cellular changes in the inflammation process (4)?

Answer 10

MARGINATION
Accumulation of leukocytes along blood vessel walls at the site of injury

ROLLING

ADHESION

DIAPEDESIS

Question 11

What is the role of chemokines in the inflammatory process (cellular change)?

Answer 11

Attract immune cells toward the site of injury

Travel toward the high concentration of chemokines = chemotaxis

Question 12

Name different times where chemotaxis is use (3)

Answer 12

Bacterial peptides
Complement
Leukotrienes

Question 13

Which adhesion molecule is used in rolling?

Answer 13

Selectin (it is on the endothelial layer)

Question 14

Which adhesion receptor is use in adhesion?

Answer 14

Integrin (it is on the endothelial layer and on the leukocytes)

PAF receptor binding activates integrins on leukocytes.

Then able to bind to ICAM-1 on the endo layer(stop rolling)

Question 15

In adhesion, LFA-1 on leukocytes interact w/ what receptor on endothelial cell?

Answer 15

ICAM-1

Question 16

In adhesion, VLA-4 on the leukocyte interact w/ which receptor on the endothelial cell?

Answer 16

V-CAM-1

Question 17

During diapedesis, which kind if integrin help WBC to transmigrate?

Answer 17

PECAM-1

Question 18

In diapedesis, what can secrete WBC to break-down the basement membrane and move through the endothelial layer?

Answer 18

Collagenases enzymes

Question 19

Neutrophils

Answer 19

Hallmark of acute inflammation

Granule contains digestive enzymes (eg.: lysozymes)

Release inflammatory mediators

Question 20

Eosinophils/basophils

Answer 20

Granules filled w/ inflammatory mediators

Useful against parasites
-part of immune reactions mediated by IgE

Life-threatening if triggered inappropriately (eg.: allergic reactions)

Question 21

Monocytes/ macrophages

Answer 21

Hallmark of CHRONIC inflammation

Releases cytokines

Cause fever in generalized inflammatory responses

Highly concentrated in

• lymph nodes
• Spleen/other immune organs

Macrophage are activated by inflammatory mediators

Question 22

How is called macrophages in the brain?

Answer 22

Microglia

Question 23

How is called macrophages if the skin?

Answer 23

Langerhans cells

Question 24

What are the 2 types of macrophage activation?

Answer 24

M1 = classical activation = IFN-y

M2 = alternative activation = IL-13 + IL-4
-activation of more powerful and specific fct
(Eg.: wound healing, phagocytosis)

Question 25

Give 2 examples of M2 activation of macrophages fct

Answer 25

Wound healing Phagocytosis

Question 26

Which cells express TLR

Answer 26

Macrophage Dentritic cells

Question 27

Activation of TLR activates macrophage to do which fct?

Answer 27

Phagocytosis Release of inflammatory mediators

Question 28

What is an inflammasome?

Answer 28

Protein complex called NLRP3 It is a sensor prot + caspase-1 = enzyme Recognises dead cell product (extacellular ATP, uric acid) and some microbe. It increases the secretions of IL-1 IL-1 fct = mediators for leukocytes recruitment

Question 29

Name 2 dead cell products

Answer 29

Extracellular ATP Uric acid

Question 30

What type of chemotaxis recruit neutrophils 1st in acute inflammation?

Answer 30

IL-8

Question 31

In phagocytosis, the process of engulfment form a phagosome. What are found in the phagosome (2)?

Answer 31

ROS Lysosomes The leakage of those during phagocytosis is the source of tissue damage CHRONIC INFLAMMATION

Question 32

Oxidative (resp) burst is trigger by what?

Answer 32

Phagocytosis It increase 02 consumption and glycolysis For extra prod of ROS

Question 33

Large non-digestible particle can be engulfed and secreted to?

Answer 33

GIT Leukocyte w/particle is excreted MACROPHAGE w/ particule can DIVIDE Daughter cell can resume normal fct Mother cell is excreted

Question 34

Which type of cell can divide before to be excreted in the GIT because of non-digestible particles engulfed?

Answer 34

Macrophages