MODULE 5 PART 1: INNATE IMMUNITY - RECOGNITION OF INVADERS

Question 1

If infectious agents such as bacteria invades the body, the most important innate mechanism to be triggered is ?

Answer 1

Acute inflammation

Question 2

It is the response of tissue to invading microorganism or tissue damage; involves the activation and directed migration of many different cells especially neutrophils and macrophages from the blood stream to sites of invasion.

Answer 2

Inflammation

Question 3

What is the first step in innate immunity?

Answer 3

Recognition of microorganisms and molecules released by damaged cells

Question 4

Microorganisms and their molecules can be detected by what type of cells?

Answer 4

Sentinel cells

Question 5

Sentinel cells have surface receptors that recognize?

Answer 5

PAMPS (Pathogen-associated molecular patterns)

Question 6

What are some examples of PAMPs?

Answer 6

• Peptidoglycan, lipoteichoic acids in gram (+) bacteria
• LPS in gram (-) bacteria
• Glycolipids in acid-fast bacteria
• DNA and some proteins
• Mannans of yeast

Question 7

These are receptors expressed on macrophages and mast cells, as well as dendritic cells, eosinophils and epithelial cells in respiratory tract and intestine.

Answer 7

TLRs

Question 8

When TLRs bind to a molecule from an invading microorganism, signal passes into its cells then _____ is activated.

Answer 8

Cytokines

Question 9

There are atleast how many TLR’s?

Answer 9

10

Question 10

TLRs is restricted to recognizing microorganism only. True or False?

Answer 10

False, also recognizes molecules produced by damaged tissues (e.g. heparin sulfate)

Question 11

This PAMP receptor binds to bacterial LPS.

Answer 11

CD14

Question 12

This PAMP receptors bind to microbial carbohydrates.

Answer 12

Mannan & glucan receptors

Question 13

This PAMP receptor binds to bacterial lipoproteins.

Answer 13

CD36

Question 14

This PAMP receptor binds to microbial glycolipids.

Answer 14

CD1

Question 15

This sentinel cell does not only act as sentinel cells but also kill invading microorganisms.

Answer 15

Macrophages

Question 16

Macrophages contribute directly to the repair of damaged tissues by ?

Answer 16

Removing dead, dying and damage cells (assist healing process)

Question 17

Immature macrophage in the blood is called?

Answer 17

Monocyte

Question 18

Type of macrophage in connective tissues

Answer 18

Histocytes

Question 19

Type of macrophage lining the sinusoids of the liver

Answer 19

Kupffer cells

Question 20

Type of macrophage residing in the brain

Answer 20

Microglia

Question 21

Type of macrophage residing in the alveoli of the lungs

Answer 21

Alveolar macrophage

Question 22

Type of macrophage residing in capillaries of lungs

Answer 22

Pulmonary intravascular macrophage

Question 23

This sentinel cell present antigens to T cells, hence regarded as antigen-processing cells.

Answer 23

Dendritic cells

Question 24

It is the only antigen-processing cells that can activate naive T cells.

Answer 24

Dendritic cells

Question 25

Dendritic cells can take up many different antigens. Give some example.

Answer 25

* Dead microorganisms * Soluble antigens in tissue fluids * Antigens released by dying cells

Question 26

This sentinel cell is a very large and round scattered throughout the body in connective tissue, under mucosal surfaces, skin, and around nerves.

Answer 26

Mast ceclls

Question 27

Connective tissue and skin mast cells are rich in ?

Answer 27

Histamine and heparin

Question 28

Mast cells are recognized by ____ that is densely packed with large granules that stain very strongly with dyes such as toluidine blue.

Answer 28

cytoplasm

Question 29

Intestinal mast cells contain what components ?

Answer 29

* Chondroitin sulfate * Little histamine

Question 30

Mast cell degranulation can be triggered by ____.

Answer 30

IgE

Question 31

If IgE triggers mast cells, what is the resulting effect?

Answer 31

Explosive release of mat cell granule contents that is responsible for the severe inflammation that occurs in allergic ds.

Question 32

Normal and severe inflammation triggers the explosive release of mast cell granule contents. True or False?

Answer 32

False, in normal inflammation, mast cells release their granule contents relative slowly through *piecemeal degranulation.*

Question 33

Bacterial peptidoglycans acting to ____ stimulate histamine release.

Answer 33

TLR2

Question 34

What are the cytokines released by the diff. sentinel cells?

Answer 34

* IL-1 * TNF-a * IL-6 * IL-12 * IL=18

Question 35

Sentinel cells can release chemokines. True or False?

Answer 35

True

Question 36

If pain is induced, what is the first triggering effect?

Answer 36

**(1) Nerves releasing bioactive peptides** Next steps: (2) Broken cells --> release intracellular proteins --> release of cytokines from sentinel cells