Immune System And Inflammation

Question 1

What are the 2 major branches of the immune system

Answer 1

• innate immune system

- adaptive immune system

Question 2

What are the features of the innate immune system

Answer 2

• first line of defense
• general response
• fast reaction
• always the same response
• doesn’t learn and evolve
• response is inflammation

Question 3

What are the features of adaptive immune system

Answer 3

• super specific : adapted to a specific pathogen
• develops memory
• slow reaction
• infinite possibility of response

Question 4

Define inflammation

Answer 4

• non specific defense
• healing mechanism of the body to tissue damage and infection
• part of the innate immune system : first line of immunological defense against pathogens

Question 5

List the cells of the innate immune system

Answer 5

Monocytes —> macrophages 
Leukocytes —> granulocytes 
Neutrophils
Eosinophils
Basophils —> histamines 
Mast cells 
Dendritic cells —> phagocytic cells ; antigen presenting cells 
Natural killer cells

Question 6

What is the function of monocytes

Answer 6

Large mononuclear cell accounting for approx. 5% of the WBC.
They mature in the circulation and then exist in the blood stream.
In tissue they differentiate into macrophages
Phagocytic cell acting as scavenger
Ingested material is enzymatically degraded by lysosomes

Question 7

What is the specificity of leukocytes ?

Answer 7

The one that contain many cytoplasmic granules are called granulocytes. These cells have multilobed nuclei. Their name is given according to the dye used to color their granules.

Question 8

What are the specificities of neutrophiles ?

Answer 8

Account for 60% of WBC

Phagocytic cells expert in killing bacterias

Question 9

What are the features of eosinophils ?

Answer 9

Up to 5% of the WBC

Play a crucial role in the defense against parasitic infections

Question 10

What are the features of basophils and mast cells ?

Answer 10

Up to 1% of WBC
They contain granules with vasoactive molecules as histamine which plays a role in allergic reactions. The difference is that mast cells are resident in some tissues.

Question 11

What are the features of dendritic cells ?

Answer 11

They have branch like cytoplasmic projections. They are found predominantly in potential portals of microbial entry.
They are phagocytic cells and antigen presenting cells.

Question 12

Which immune cells are the link between innate and adaptive systems ?

Answer 12

Dendritic immune cells

Question 13

What are the features of natural killer cells ?

Answer 13

Up to 5% of the WBC

Non specific lymphocytes killing virus and tumoral cells

Question 14

What is the time line of inflammatory response ?

Answer 14

• recognition
• recruitment
• removal
• resolution/repair

Question 15

What are the characteristics of an inflammatory response ?

Answer 15

Pain
Redness 
Heat 
Swelling 
All in the site of infection

Question 16

What is the tool of innate immune system to spot pathogens ?

Answer 16

Pattern Recognition Receptors which may be soluble or bound to a host cell

Question 17

What are pathogen associated molecular patterns ?

Answer 17

Conserved, structural features expressed by microbes but not by the host cell.
Two common bacterial products that contain PAMPs are lypopolisaccharide and peptidoglycan.

Question 18

What is the tool of immune system to recognize damaged cells ?

Answer 18

Pattern recognition receptors

Question 19

What are danger associated molecular patterns ?

Answer 19

Exposure of molecules from injured tissues, such as cytosolic or nuclear proteins

Question 20

In what does signal transduction from TLR result into ?

Answer 20

Synthesis and production of pro-inflammatory cytokines

Question 21

What is the role of scavenger cells in the recognition phase ?

Answer 21

They mediate the internalization of bacteria and the phagocytosis of host cells undergoing apoptosis.