47-Overview of Immunology

Question 1

What is immunology?

Answer 1

The study of the response of an organism to microbes and allergens

Question 2

Why is immunology important for clinical biology?

Answer 2

T cells are involved in most major pathological disorders

Question 3

When was the initial description of immunity

Answer 3

5000 BCE in China

Question 4

What did Thucydides do?

Answer 4

In 430 BCE first used the word immunity to describe individuals that survived the plague did not get sick again “immunological memory”

Question 5

When was the 1st purposeful injection?

Answer 5

1000 in China “variolation”. Blew smallpox pus into noses. Variolation 2% death rate. small pox 35% death rate

Question 6

What did Edward Jenner do?

Answer 6

Observed that milk maids didn’t get smallpox because they were exposed to cowpox. Infected the gardener’s son with cow pox and then small pox “vaccination”

Question 7

What did Robert Koch do?

Answer 7

In 1876 proved the germ theory with the causative agent for anthrax

Question 8

What did Louis Pasteur do?

Answer 8

1880’s developed live attenuated vaccines for chicken cholera, anthrax, and rabies

Question 9

When was the germ theory developed?

Answer 9

1840

Question 10

What did Elie Metchnikoff do?

Answer 10

In 1883 discovered phagocytic white blood cell ingesting pathogens “macrophages”

Question 11

What did Emil von Behring do?

Answer 11

In 1890 identified serum of animals immune to diphtheria had antibodies

Question 12

What did Shibasaburo Kitasato do?

Answer 12

In 1890 identified serum of animals immune to diphtheria had antibodies

Question 13

What did Emile Roux do?

Answer 13

Worked with Behring and Kitasato to develop first anti-serum treatment for diphtheria

Question 14

What is a pathogen?

Answer 14

Organism with ability to cause host damage

Question 15

How does the immune system differentiate between pathogen and non pathogen?

Answer 15

It can’t. it just responds to microbes

Question 16

Pathogenicity of microbe is defined by what?

Answer 16

The microbe and the immune response

Question 17

Infection and disease are….?

Answer 17

Related, but distinct. You can get infected without getting a disease

Question 18

What are the different types of pathogens?

Answer 18

Virus, Bacteria, Parasite, Worm

Question 19

The immune system can respond to what external substances?

Answer 19

Allergens

Question 20

What are the 3 main lines of defense against a pathogen?

Answer 20

Barriers, Innate response, Adaptive response

Question 21

What are examples of barriers?

Answer 21

physical, chemical, microbiome

Question 22

What are the types of innate response?

Answer 22

phagocytosis, granulocytes, inflammation, proteins

Question 23

What are the types of adaptive response?

Answer 23

T cells, B cells/antibodies

Question 24

How does a barrier fail?

Answer 24

wounds, defective membrane, chronic disease, malnutrition, insect bites, pathogenicity

Question 25

What happens when a barrier fails?

Answer 25

Innate response starts

Question 26

How long does it take for the innate response to start?

Answer 26

Minutes to hours

Question 27

What is the response initiator for innate response?

Answer 27

broad classes of molecules

Question 28

How long does it take for the adaptive response to start?

Answer 28

days to weeks

Question 29

what is the response initiator for adaptive response?

Answer 29

specific antigen

Question 30

What is the timing of an immune response?

Answer 30

Barrier is breaches, rapid activation of innate response then adaptive immune response is activated to clear pathogen. Adaptive immune cells develop into memory cells

Question 31

What is required for the immune response?

Answer 31

both the innate and adaptive immunity

Question 32

innate immune response is activated by what?

Answer 32

pattern recognition receptors

Question 33

pattern recognition receptors are activated by what?

Answer 33

conserved features of pathogens (cell wall, nucleic acids, bacterial flagellin) essential for viability

Question 34

examples of pattern recognition receptors:

Answer 34

TLR, NLR, RIG-I

Question 35

What is inflammation?

Answer 35

hallmark of the activation of the innate immune response

Question 36

how is inflammation activated?

Answer 36

release of inflammatory mediators

Question 37

what are the five signs of inflammation?

Answer 37

``` redness (rubor) heat (calor) swelling (tumor) pain (dolor) loss of function ```

Question 38

what are the 4 functions of inflammation?

Answer 38

recruit immune cells enhance immune cell function limit spread of infection promote tissue repair

Question 39

What are the steps of phagocytosis?

Answer 39

chemotaxis (movement to site of infection) ingestion of pathogen into phagosome formation of phagolysosome by fusing to lysosome digestion of pathogen release of debris that is highly inflammatory

Question 40

where does t cell activation occur?

Answer 40

secondary lymphoid tissues 1-lymph nodes: antigens from tissues via lymph system 2-spleen: antigens from bloodstream via circulatory 3-Mucosa associated lymphoid tissues: antigens from mucosal surfaces

Question 41

What is the role of the secondary lymphoid organs

Answer 41

localize antigen specific T and B cells with their antigen

Question 42

How is the adaptive immune response activated?

Answer 42

antigen receptors on the surface of B and T cells

Question 43

What does the T cell receptor associate with?

Answer 43

MHC molecules bound to specific antigen

Question 44

What does the B cell receptor associate with?

Answer 44

free antigens

Question 45

What is the hallmark of adaptive immune response?

Answer 45

Clonal Expansion

Question 46

What is Clonal expansion?

Answer 46

recognition of antigen by BCR or TCR results in proliferation of the cell to increase numbers and fight infection

Question 47

Explain how memory t and plasma cells respond to reinfection

Answer 47

1st encounter: expansion of specific T cells followed by contraction. remaining T cells differentiate into memory T cells. memory B cells and plasma cells also form 2nd encounter: Protective immunity, rapid expansion of t cells and enhanced antibody production before disease infection years later: Immunological memory, expansion of t and b cells and increased antibody production before full blown disease occurs