Introduction to Immunology - Hinterleitner

Question 1

What are the 4 classes of pathogens?

Answer 1

1. Viruses
2. Bacteria
3. Fungi
4. Parasites

Question 2

What is the strategy of the innate immune system?

Answer 2

Detect conserved molecular patterns common to groups of pathogens.

Question 3

What is the strategy of the adaptive immune system?

Answer 3

Detect unique components of a particular pathogen.

Question 4

What are the limitations of the innate immune system (3 things)?

Answer 4

1. Fixed recognition strategy
2. No memory
3. Only limited amplification of the response

Question 5

How does the adaptive immune system contribute to immunity (4 things)?

Answer 5

1. Adds to ongoing innate response
2. Highly specific
3. Unique receptors by gene rearrangement
4. Long-lasting memory

Question 6

What are the lymphocytes?

Answer 6

B-cells and T-cells

Question 7

What are B-cells main function?

Answer 7

Produce antibodies

Question 8

What are T-cells main function?

Answer 8

Kill infected cells and direct innate and lymphocyte responses

Question 9

What are the limitations of adaptive immunity?

Answer 9

1. Slow
2. Can be evaded

Question 10

Where do all immune cells originate?

Answer 10

Hematopoietic stem cells in bone marrow

Question 11

What are the innate immune cells (7)?

Answer 11

1. Macrophages
2. Dendritic cells
3. Neutrophils
4. Eosinophil
5. Basophil
6. Mast cells
7. NK cells

Question 12

Where do T-cells differentiate?

Answer 12

The thymus

Question 13

How do lymphocytes encounter pathogens?

Answer 13

They circulate between the blood and peripheral lymphoid tissues until they encounter their antigen

Question 14

What is the complement system?

Answer 14

Soluble molecules and pattern recognition receptors that detect and destroy pathogens

Question 15

How does the innate immune system recognize pathogens all throughout the cell?

Answer 15

1. Surface - Toll-like, mannose-binding, etc
2. Cytoplasmic - CARD-family, Nod-like
3. Endosomal - Toll-like

Question 16

What is clonal selection?

Answer 16

The process by which only B/T-cells with receptors to recognize a specific pathogen out of a pool of many specificities will activate and proliferate.

Question 17

B-cell Receptors (BCRs)

Answer 17

• Called antibodies or Igs (immunoglobulin)
• Express many copies on the surface
• Recognize whole antigen or intact microbe/protein

Question 18

Antibody Structure

Answer 18

• 2 binding sites
• Made up of heavy and light chain

Question 19

What happens when a resting B-cell encounters a pathogen?

Answer 19

Resting B-cells have Igs expressed on their surface. When in contact with a pathogen, they will activate and secrete antibodies (now called plasma cells)

Question 20

Functions of Antibodies

Answer 20

• Opsonization
• Block toxins
• Direct lysis of bacteria

Question 21

T-cell receptors

Answer 21

• Only expressed on surface
• Recognize small fragments of pathogens-derived proteins only if they are bound to self, MHC

Question 22

Summarize T-cell Recognition of Infection

Answer 22

Pathogen-derived proteins will be phagocytosed and degraded. Small fragments will be loaded onto MHC and T-cells will bind.

Question 23

What are T-cells main function (2)?

Answer 23

1. Destroy infected cells
2. Direct immune cells in response

Question 24

Principle of Flow Cytometry

Answer 24

• Detect fluorescently labeled antibodies on the surface of individual cells in a suspension.
• Can identify different cell-types by different fluorescent tags.
  -Intensity of color says something about how many of that cell-type are in suspension.