Overview of the Immune System (Part 2)

Question 1

what are 3 words to describe receptors in the innate immune?

Answer 1

1. encoded in germline (prescribed)
2. limited number
3. unchanging

Question 2

what are 3 types of phagocytic cells?

Answer 2

1. macrophages
2. neutrophils
3. dendritic cells

Question 3

what is the function of innate response?

Answer 3

local inflammation

Question 4

how does the innate response change with repeat infection?

Answer 4

it is the same each time

Question 5

when does the adaptive response develop?

Answer 5

5-6+ days

Question 6

describe the receptors in the adaptive response

Answer 6

randomly generated and highly diverse + specific

Question 7

what are the 3 results of adaptive immunity?

Answer 7

1. SPECIFIC immune responses
2. clear infections
3. memory

Question 8

how does the adaptive response change with repeat infection?

Answer 8

response becomes more rapid and effective with each subsequent exposure

Question 9

how long does the innate immune response usually last?

Answer 9

up to days

Question 10

what is the first step of infection?

Answer 10

pathogen breaches the epithelial cell layer and enters the body

Question 11

how do local innate immune cells recognize the pathogen?

Answer 11

by Pattern Recognition Receptors (PRRs) expressed by the sensor immune cells

Question 12

what is the role of PRRs?

Answer 12

they are receptors that differentiate btwn self and non-self and recognize PAMPs

Question 13

what part of the pathogen is recognized by immune cells?

Answer 13

Pathogen-Associated Molecular Pattern (PAMPs)

Question 14

what are PAMPs?

Answer 14

foreign structures that are common to types of pathogens/microorganisms

Question 15

what happens once PAMPs on pathogens are detected by PRRs on dendritic cells?

Answer 15

dendritic cells become activated

Question 16

what happens once PAMPs on pathogens are detected by PRRs on macrophages and neutrophils?

Answer 16

macrophages and neutrophils can induce effector functions on cells, like phagocytosis

Question 17

how do macrophages and neutrophils amplify the immune response?

Answer 17

produce cytokines and chemokines

Question 18

what is the role of chemokines and cytokines?

Answer 18

inflammation

Question 19

what 2 effects do chemokines and cytokines have on blood vessels?

Answer 19

1. vasodilation
2. vascular permeability

Question 20

what 3 things do vasodilation and vascular permeability lead to?

Answer 20

1. redness
2. heat
3. swelling

Question 21

what effect do cytokines and chemokines have on immune cells in the blood?

Answer 21

they recruit them from the bloodstream to the tissue at the site of infection

Question 22

what does immune cell migration into tissue cause?

Answer 22

pain

Question 23

what are the 4 hallmarks of inflammation?

Answer 23

1. redness
2. heat
3. swelling
4. pain

Question 24

what is the role of dendritic cells?

Answer 24

present antigen to T cells to activate them

Question 25

where are immature dendritic cells located?

Answer 25

in peripheral tissue

Question 26

where do activated dendritic cells migrate when they carry an antigen?

Answer 26

migrate to lymphatic system and lymphoid organs

Question 27

where does T and B cell activation occur?

Answer 27

lymph node

Question 28

what is the order of cell activation with dendritic, T, and B cells?

Answer 28

Dendritic cells activates T cells which activates B cells

Question 29

what type of cells activate T cells (i.e. what type of cells are dendritic cells)?

Answer 29

Antigen Presenting Cells (APCs)

Question 30

what are the 3 signals that occur to activate T cells?

Answer 30

1. activation 2. survival 3. differentiation

Question 31

what part of the antigen is presented by APCs?

Answer 31

epitope

Question 32

what molecule on the APC is used to present the antigen to the T cell?

Answer 32

Major Histocompatibility Complex (MHC)

Question 33

what does the MHC interact with?

Answer 33

TCR

Question 34

how is the epitope produced from an antigen?

Answer 34

proteases break down the antigen

Question 35

what determines the specificity of T and B cells to their antigen?

Answer 35

receptors

Question 36

where are T cell receptors (TCR) located?

Answer 36

on membrane only

Question 37

where are B cell receptors (BCR) located?

Answer 37

on membrane or secreted as antibodies

Question 38

what are antibodies?

Answer 38

secreted immunoglobulin molecules

Question 39

what are antibodies made by?

Answer 39

made by B lymphocytes and its progeny

Question 40

what do antibodies bind?

Answer 40

antigens

Question 41

where are antibodies located?

Answer 41

in serum

Question 42

are 2 antibodies able to bind the same epitopes on the same antigen?

Answer 42

yes

Question 43

where do B cells arise and mature?

Answer 43

in bone marrow

Question 44

where do T cells arise and mature?

Answer 44

arise from bone marrow progenitors and are generated + mature in thymus

Question 45

what is different about how TCR and BCRs recognize antigens?

Answer 45

TCR only recognize epitopes, BCR can recognize full antigens

Question 46

describe the specificity of individual B and T cells for an antigen

Answer 46

each cell has individual specificity for 1 antigen --> each cell has many copies of 1 receptor for 1 antigen

Question 47

is each lymphocyte specific or does it have many types of receptors?

Answer 47

each lymphocyte is very specific and contains many copies of 1 receptor

Question 48

what does having many types of specific lymphocytes allow for?

Answer 48

allows for a huge diversity of lymphocytes, so the body is ready to respond to any antigen

Question 49

how is the diversity of lymphocytes accomplished?

Answer 49

by rearranging and editing genomic DNA encoding for the antigen receptors

Question 50

how are self-reactive cells removed?

Answer 50

if a lymphocyte reacts to a self antigen during development, it is removed

Question 51

when are lymphocytes selected for activation?

Answer 51

when the lymphocyte interacts with its specific antigen, it is selected and becomes activated

Question 52

what happens to lymphocytes once they become activated?

Answer 52

lymphocytes proliferate to produce many clones

Question 53

describe the clones produced from activated lymphocytes?

Answer 53

each clone is reactive against the antigen

Question 54

why does our body need to make clones of lymphocytes?

Answer 54

bc there is always a lot of pathogen

Question 55

what type of cells do lymphocytes become once they are activated in lymphoid organs?

Answer 55

effector cells

Question 56

what are effector cells?

Answer 56

cells that can fight infections

Question 57

what type of immunity is used by B cells and antibodies?

Answer 57

humoral immunity

Question 58

what type of immunity is used by T cells?

Answer 58

cell-mediated immunity

Question 59

what are 3 possible functions of cell-mediated immuntiy?

Answer 59

1. some activate B cells 2. some help to activate macrophages 3. some kill infected cells

Question 60

in what situation would cell-mediated immunity by T cells need to help activate macrophages?

Answer 60

if the macrophage has taken up a pathogen which prevents phagocytosis

Question 61

what are the 2 roles of antibodies in humoral immunity?

Answer 61

1. clear the antigen 2. neutralize the antigen

Question 62

how do antibodies clear the antigen?

Answer 62

bind the pathogen to recruit phagocytic cells

Question 63

how do antibodies neutralize the antigen?

Answer 63

bind the antigen so it can't bind anything else

Question 64

what happens once the infection has cleared (2)?

Answer 64

1. downregulate T cells 2. memory

Question 65

what is immunization?

Answer 65

deliberate induction of an adaptive immune response

Question 66

what are the 4 types of immunization?

Answer 66

1. active - natural 2. active - induced 3. passive - natural 4. passive - natural

Question 67

what does active immunization require?

Answer 67

requires a working immune system

Question 67

what does active immunization require?

Answer 67

requires a working immune system

Question 68

what is natural active immunization?

Answer 68

natural infection

Question 69

what is induced active immunization?

Answer 69

vaccination

Question 70

what is passive immunization?

Answer 70

with cells/molecules that mediate immunity

Question 71

what is natural passive immunization?

Answer 71

mother-to-fetus transfer of antibodies

Question 72

what is induced passive immunization?

Answer 72

monoclonal antibody therapy

Question 73

what does the immune system do in passive immuization?

Answer 73

nothing