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Immune System > Definitions And Questions > Flashcards

Definitions And Questions Flashcards

1
Q

What is the function of the immune system?

A

Is a diffuse collection of cells and organs that are responsible for the ability to resist infections and diseases

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2
Q

What does the immune system protect the rest of the body from?

A

Pathogens, toxic material, and its own misfunctioning cells

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3
Q

What system does the immune system closely intertwined with?

A

With the lymphatic system, but not completely overlapping

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4
Q

The body has multiple layers of défense against infections. What are est 2 defences and describe them each.

A

Physical Barrier: Anatomical and physiological mechanisms that prevent entry of foreign organism and substances

Cell-mediated immune responses: Innate and adaptive defence responses that rely on WBC activity

-> Innate immune response: cell recruitment to injured tissue and release of pro inflammatory mediators
-> Adaptive Immune Activation: Activation and clinal expansion of lymphocytes

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5
Q

Physical barriers

A

Are protective features that are created by non-immune cells

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6
Q

Anatomical/Physiological (physical) barriers come in 2 major categories:

  • Structural features
    -> Ex: skin - describe the skin
  • Chemical secretion
A

Structural features: that work to prevent a pathogen from entering the body. (Ex: skin and hair)
- describe the skin: lecture #36 slide 6

Chemical secretions: that are used to neutralize and destroy them (ex: iysozyme, stomach acid)

These défenses are all creates by cells that are not primary immune cells in their functions.

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7
Q

There are 3 components to the physical barriers made by the integument:
- know the layer and what they lead to

A
  • Secretion: Wash away (and/or destroy) potential pathogens
  • Hair: Keep potential hazards away form the skin surface
  • Stratified squamous epithelium: Many closely interlocked layered which keep intruders out
  • see diagram in lecture #36 slide 7
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8
Q

Mucous membranes
- list the 2
- draw the diagram

A

Line the digestive, respiratory, urinary, and reproductive tracts… which all connect to the outside world.

They provide protection against foreign substances and pathogens

  1. Secretion
  2. Tight interlocking: Epithelial cells tied together by tight junctions and supported by fribourgeois basement membrane

-> draw out the diagram Lecture #36 slide 8

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9
Q

Immune responses are meditated by…

A

White blood cells

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10
Q

Both the innate and adaptive immune response rely on..

A

The activation and signalling of specialized immune cells

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11
Q

White blood cells (WBCs) are responsible for both…

A

Both types of immune response

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12
Q

Is WBCs only found in blood?

A

NO it is not ONLY found in blood

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13
Q

White blood cells are born in..

A

Hematopoietic red bone marrow

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14
Q

White blood cells can be divided based on:

A
  • Function
  • Anatomy
  • Developmental history
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15
Q

What are the components of the Immune responses mediated by WBCs?

A
  1. Detection/Recognition: of invaders of abnormality (ex: NK cell)
  2. Secretion: of chemicals that alter the local environment of signal to other cells (ex: Interferon alpha)
  3. Destruction: of foreign particles pathogens, and diseased cells (ex: free macrophages)
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16
Q

Innate immune response
- list the cell and what do they look like?

A

Are nonspecific responses that react to any threat they detect they are present from birth.

List:
- Neutrophil
- Basophil
- Eosinophil
- Monocyte
- Macrophage
- Mast cell
- Natural killer

Exception:
- Dendritic cell is in both

  • Lecture #36 slide 13
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17
Q

Adaptive response
- list the examples
- and what do they look like?
- what is the exception

A

Are specific and powerful responses triggered by exposure to particular antigens. They must be ‘learned’ over the lifetime

  • T lymphocyte
  • B lymphocyte

Exception:
- Dendritic is both

  • Lecture #36 slide 13
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18
Q

Analogies of the levels of immune system

A

Physical/Chemical Barriers: Keep most things out
Innate Immunity: Front lines for most things that get in
Adaptive Immunity: Saved for the really precise tasks

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19
Q

The lymphatic system consists of…

A

Vessels that move lymph through the body, and tissues that produce or house lymphocytes

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20
Q

Lymph

A

Is a fluid connective tissue that resembles blood, but it lacks most of the cells and most of the plasma proteins

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21
Q

The lymphatic system is NOT…

A

Synonymous with the immune system - it also has non-immune functions

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22
Q

There are 2 main non-immune functions of the lymphatic system:

A
  1. Return of filtered fluid from ISF to plasma
  2. Transport of digested and absorbed lipids
  • look at diagram on lecture #36 slide 18
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23
Q

Lymphatic vessels are present in almost every tissue in the body but have key differences from blood vessels. What are the similarities?

A
  • both have an endothelial wall around a lumen
  • larger vessels have a smooth muscle layer and contain valves that keep lymph flowing one way
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24
Q

Lymphatic vessels are present in almost every tissue in the body but have key differences from blood vessels. What are the differences?

A
  • lymph capillaries have blind ends
  • All lymph vessels are typically more permeable along their length
  • there is no equivalent of a heart to create pressure gradient to move lymph; it relies on smooth muscle contraction (and skeletal muscle pumps)
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25
Q

Lymph’s are better carry… so it is found near the …

A

Lymph’s are must better at carrying lipids. That is why are at found more near the digestive system

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26
Q

The lymphatic system also consists of….

A
  • lymphocytes
  • lymph nodes
  • lymphoid
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27
Q

lymphoid organs and lymphoid tissues all belong to the … and contain…

A
  • immune system
  • lymphocytes (a subset of WBCs)
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28
Q

Primary lymphoid structure

A

Involves in the production and maturation of lymphocytes

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29
Q

Secondary lymphoid structures

A

Contains mature and functional lymphocytes

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30
Q

Tissues:

A

Lack a distinct capsule (ex: lymphoid tissue)

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31
Q

Organs

A

Have distinct fibrosis capsule (ex: lymph nodes)

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32
Q

Lymphatic system is not synonymous with _______ because

A

Immune system because not all WBCs are lymphocyte

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33
Q

Lymphocytes

A

Are a developmental classification; all lymphocytes are come from lymphoid stem cells

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34
Q

All other WBCs develop from…

A

Myeloid stem cells (like RBCs and platelets)

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35
Q

Most (but not all) lymphocytes are associated with _________

A

Adaptive immune response

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36
Q

Draw a graph of the classes of lymphocytes

A

Note: no matter which way you try to divide WBC types, there will always be an exception that makes it hard to find a simple rule

  • lecture #36 slide 21
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37
Q

Lymph nodes

A

Are encapsulated structures which are connected to lymph vessels and house mature lymphocytes
-> draw the diagram on lecture #36 slide 24

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38
Q

Lymph nodes monitor lymph for ___________, which can ________________

A
  1. Possible antigens
  2. Stimulate immune responses
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39
Q

Lymph within lymph vessels flows…

A

Into and through lymph nodes, which are often clustered at joints and where peripheral lymph vessels meet the torso

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40
Q

What are lymph nodes
- are filled with?
- have a ________ capsule

A
  • B and T lymphocytes (plus some other WBCs)
  • connective tissue capsule
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41
Q

Describe Lymph nodes and their function regarding stimulate immune response
- draw the diagram and what are the steps involved for this steps?

A
  • Filter lymph
  • act as staging posts for generating adaptive immune responses to antigens dented by the innate immune system
  • see lecture #36 slide 25
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42
Q

Lymph leaving lymph nodes has been _______

A

Filtered

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43
Q

Activated lymphocytes
- draw the diagram

A
  • That have acquired specific adaptive immune responses leave the lymph node through efferent vessels
  • results to the circulation in they lymph
  • lecture #36 slide 26
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44
Q

Macrophages in the medulla help…

A

Destroy pathogens that make it into the lymph vessels, before they reach the bloodstream

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45
Q

Not all mature lymphocytes are associated with… why?

A
  • Lymph nodes - there are other secondary lymphoid tissues
  • these tissue contain aggregation of lymphocytes that act like lymph nodes but possess structural differences
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46
Q

Spleen

A
  • An organ with high amounts of lymphoid tissue that filters and monitors the blood
  • like lymph nodes, it contains clusters of lymphocytes within its white pulp. which generate adaptive immune responses
  • is a lymphoid organ (bc/ the spleen is surrounded by a capsule, but the organization of lymphocyte clusters is more similar to that seen in lymphoid tissue - like lymphoid tissue); it also has non-lymphoid functions, such as recycling old RBCs in its red pulp
  • filters blood plasma, not lymph - it acts like a lymph node for the blood
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47
Q

Lymphoid noodles are aggregations of …

A

Lymphocytes that lack a distinct capsule.
They are also called “mucosa associates lymphoid tissue” or MALT

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48
Q

Lymphoid nodules

A

Are regions of lymphoid tisse that are typically associated with mucosa

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49
Q

Other researchers distinguished that many subtypes of MALT are mostly based on______ and other categorize MALT by the ________ …

A
  1. location
  2. the structure of the aggregations
    - refer to lecture #36 slide 28
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50
Q

Lymphoid nodules are distinguished from lymph nodes by their …..

A

location and their organization

51
Q

What do both lymph nodes and lymph nodules contain?

A

B and T cells that generate adaptive immune response

52
Q

Lymph nodules

A
  • have no capsule and no afferent vessels
  • are found in areolar tissue within mucous membranes
  • their density is highest where there are many live pathogens in the lumen
53
Q

What are the 2 sections cell-mediated immunity is dividing into?

A

Innate and adaptive immune response

54
Q

Innate response
- what cells are involved in this response and what do they look like?

A
  • Present form birth/ not learned
  • general -> the same for every threat
  • Lecture #37 page 4
55
Q

Adaptive immune system
- what cells are involved in this response and what do they look like?

A
  • learned response
  • specific response
  • lecture #37 page 4
56
Q

What does cell-mediated immunity also involve?

A
  • Acellular soluble factors, including cytokines and complements(a group of plasam proteins that contribute to anti-microbial deenses)
57
Q

Acellular soluble factors

A

Are secreted molécules which are involved in immune response

58
Q

Acellular soluble - Complement
- what does it look like

A

A group of plasma proteins that contributes to the anti-microbial defences
- lecture #37 page 5

59
Q

Acellular soluble - Cytokine
- what does it look like?

A
  • any signalling molecule that is used as part of cell-mediated immune responses

Diverse (chemically and functionally) and can be:
- paracine or endocrine
- acting on non-immune cells or by immune cells
- released by non-immune cells or by immune cells
- enhancing immune responses or suppressing them

Lecture #37 page 5

60
Q

What are the 3 basic components of an innate immune response and explain them each.

A
  1. Recognition: identifications of pathogens or abnormal cells
  2. Resolution: destruction of pathogens, and diseased cells
  3. Recruitment: structural and chemical changes that bring WBCs to the site
61
Q

What can the innate immune response also be called?
- it’s divided into 2 phases. What are those phases and explain

A

Inflammatory immune responses

Phase 1: Immediate Response
- generated by cells and soluble factors already present in the local tissue

Phase 2: Induced Response
- occurs with the recruitment of WBCs (especially phagocytes) from blood circulation

62
Q

What are the the 5 cardinal ( or hallmark) signs of inflammations?

A
  • heat
  • redness
  • swelling
  • pain
  • loss of function
63
Q

Resident WBCs (ex: Mast cells)

A
  • recognize tissue damage and pathogen entry and release signalling molecules

Steps:
1. Mast cell is activated by chemicals released from damages epithelium
2. Mast cells degranulates releasing granule contents; histamine, heparin, and cytokines

  • see the diagrams lecture #37 page 9
64
Q

Chemokine

A

Cytokines that functions to attract WBCs to move toward it

65
Q

What does the release of paracrine factors from mast cells lead to?
- what does this look like?

A

Structural and physiological changes in the local tissue
- these signalling molecules have many non-immune cell targets in local tissue. Promoting different processes
- lecture #37 page 10

66
Q

The release of cytokines, (especially interleukins) into the bloodstream leads to?
- there are 2 examples

A

Can generate body-wide aspects of inflammatory response

Example 1: Interleukin 1 (IL-1) can reprogram the hypothalamic set point for temp, triggering fever

Example 2: interleukin 6 (IL-6) can stimulate proliferation of WBCs (especially neutrophils) in red bone marrow

  • see the diagrams lecture #37 page 11
67
Q

The release of paracrine and hormonal factors from mast cells leads to?

A

The recruitment of circulating WBCs through extravasions

Extravasation involves:
1. Changes in the endothelial wall (allowing WBCs to stick to it)
2. Chemotaxis of WBCs into the interstitial spaces
- lecture #37 page 13

68
Q

Phagocytic myeloid cells
- what type of phagocytes are there?
- what does the diagram look like?

A

Resolve infection by engulfing and destroying pathogens

Phagocytes:
- Neutrophils
- Eosinophils
- Macrophages -> Monocyte -> fixed macrophages or free macrophages

Lecture #37 page 14

69
Q

What are the different types of phagocytes and what do they respond to?
- draw the graph

A

Neutrophils: very abundant; the main cell type recruited during innate immune responses

Eosinophils: mostly phagocytoses pathogens that have already been targeted by antibodies

Macrophages: can be resident or recruited; involved in innate responses, removal of dead cell debris, and sometimes act as antigen-presenting cells (APC)

70
Q

Pus

A
  • Is a mixture of protein-rich fluid and dead leukocytes (mostly neutrophils) at a local site of infection
  • is more common form bacterial infections than other types of infection, so it is not a reliable sign of an inflammatory response
71
Q

Complement protein

A
  • Are soluble immune mediators that assist in resolving microbial infection when activated
  • complement proteins are synthesized by the liver, and circulate in blood plasma
72
Q

what happens to complement protein when they are activated

A

They generate an enzyme cascade (somewhat analogous to the coagulation cascade) that can lead to pathogen death

  • look at the digramme lecture #37 page 17
73
Q

What is the core of the complement cascade? And what does it lead to?
- draw the diagram and explain each part

A

Is the activation of Complement C3, which leads to both inflammatory and direct-attack response
- lecture #37 page 18

74
Q

How can the complement system be activated? There are 3 distinct pathways
- draw and describe the diagram

A
  1. Classical Pathway:
    -> C3 activated by integration with antibodies (requires an adaptive immune response
  2. Lectin Pathway:
    -> C3 activated by interaction with bacterial cell wall
  3. Alternative Pathway:
    -> Cab stabilized by Complement Factor P (properdin) - stimulated by bacterial secretions
  • lecture #37 page 19
75
Q

Describe the “road map” for innate immunity : Microbial infections
- remember the definition of the 3 basic components of an innate immune response

A
  1. Recognition: Mast cells, complement system
  2. Recruitment:
    -> Cytokines - vessel dilation, permeability, chemotaxis and extravasation of WBCs
  3. Resolution:
    -> Phagocytosis - especially by neutrophils and macrophages
    -> Lysis - by complement membrane attack complex
76
Q

Natural Killer (NK) cells
- what does it look like?

A
  • perform immune surveillance locating (and destroying) abnormal self cells
  • can recognize abnormal cells either by unusual cell surface proteins (both infected and tumours) or through the secretion of a cytokine called ‘interferon alpha’
  • lecture # 37 page 24
77
Q

An abnormal ‘self cell’ is a body cell that is either:

A
  1. Infected by a virus
  2. Part of a tumour
78
Q

Natural killer cells resolve infection by releasing substances that ….
- what are the steps and what does it look like?

A

Trigger cell membrane permeability and lysis

Steps:
1. Recognition and adhesion
2. Realignment of Golgi Apparatus
3. Secretion of Perforin
4. Lysis of Abnormal Cell

79
Q

What can Natural Killer cells also release?

A

NK cells can also release a cytokine called tumour necrosis factor alpha which acts as a paracrine signal that cen induce apoptosis in tumour cells

80
Q

Cytokines released form Natural Killer cells attract?

A

Phagocytes which remove the cellular debris

81
Q

Interferon gamma (IFN-y)
- what does it look like?

A

Can act as a chemokine, attracting and stimulating macrophages (and other cells) to the site
-lecture #37 page 26

82
Q

What is the ‘road map’ for innate immunity; Immune Surveillance
- remember the definition of the 3 components of immune response

A
  1. Recognition: interferon-alpha, cell-surface molecules
    2.Recruitment: Interferon-alpha, other cytokines, enhancing chemotaxis of NK cells
  2. Resolution: Lysis (by perforin) and induction of apoptosis (by TNF - alpha)
83
Q

When does adaptive immunity come into play?

A

Innate immunity unable to remove pathogen -> a “bat signal” is sent out to call for them -> proceed with adaptive immune response

84
Q

What makes the adaptive immune system different than innate? (General)

A

Innate immunity is non-specific and genetically determined compared to adaptive immunity is acquired following antigen exposure

85
Q

What makes the adaptive immune system different than innate? (Specific)

A
  1. Specificity
    - T and B cells are equipped with receptors that recognize a specific antigen
    - activated lymphocytes direct their attack specifically at their cognate antigen and ignore other antigens
  2. Memory
    - Activated lymphocytes dived into effector or inactive memory cells
    - memory cells mount a faster, stronger, and more efficient attack during subsequent antigen exposure
  3. Versatility
    - Each lymphocytes recognize a specific antigen
    - People posses millions of lymphocytes
    - Therefore, a massive diversity of antigens can be recognized by lymphocytes
  4. Tolerance
    - Ensures “self: tissue are ignored while “non-self” tissue are considered a threat
    - Usually genetically established but can be induced by repeated antigen exposure
86
Q

What is the “Big Picture” Overview of Adaptive Immunity?
- draw out the diagram
ーdescribe the key players

A

Key Players:
Antigens: are molecules that stimulate an immune response

Antigen-presenting cells: prepare and present antigens to lymphocytes

T cells: execute cell-mediated immunity to physical or chemicals destroy pathogens and infected cells

B-Cells: facilitate humoral immunity and produce antibodies that target antigens for destruction

-Lecture #38 page 6

87
Q

Describe the components of the lymphocyte lifecycle

A

Lymphocyte lifecycle: maturation, selection, activation

Step:
1. Red bone marrow
-> production site of lymphocyte precursors

  1. Thymus
    -> Site of T cell selections, differentiation or death
  2. Peripheral lymphoid organs and tissues
    -> Site of immune cell surveillance, activation, and proliferation
  3. Undergoes apoptosis weeks - years after production
88
Q

Primary Lymphoid

A

Sites where lymphocytes are produced and mature

89
Q

Secondary Lymphoid Structures

A

Sites where lymphocytes are activated

90
Q

How do lymphocytes determine their target?

A
  • Lymphocytes only recognize antigens where they are bound to MHC (major histocompatibility complex) molecules
  • there are 2 difference MHC molecules:
    -> MHC class 1 and MHC class 2
  • when antigen is present by an MHC molecule, lymphocytes learn to direct their attack against that specific antigen and nothing else
91
Q

Where are Intracellular antigens presented?

A

On MHC class 1

92
Q

Intracellular antigens

A
  • ex: from viral or bacterial infections
  • undergoes processing and presentation through the MHC class 1 pathways
  • MHC class 1 molecule are located on teh surface of all uncleared cells

(Understand the diagram and chart in lecture #38 page 10)

93
Q

Where are extracellular antigens presented?

A

On MHC Class 2

94
Q

Extracellular antigens

A

Are phagocytoses, broken down into smaller peptides, then loaded onto MHC class 2 molecules for cell surface presentation

95
Q

Where are MCH class 2 molecules exclusively located?

A

On the surface of antigen presenting cells and lymphocytes
- remember the diagram on lecture #38 page 11

96
Q

T cell activation relies on __________ which relied on _________

A
  1. Antigen recognition
  2. Antigen presentation
97
Q

What are MHC molecules recognized by

A

Receptors on T cell surface

98
Q

T cell receptors

A
  • are unique lymphocyte; different lymphocytes recognize different antigens
  • are recognized by different types of T cells which generates differ to immune responses against the presented antigen
99
Q

Different type of T cells recognize different MHC molecules
- knowing this what are the points you need to remember
- what does the diagram look like

A
  • there are 350 types of cluster of differentiation (CD) markers that can exist on the surface of leukocytes
  • CD types and number are different across all types of leukocytes
  • CD markers play a role in antigen recognition, intercellular communication and environment sensing
  • Lecture #38 page 13
100
Q

What does antigen recognition and co-stimulation lead to?

A

CD8+ T-cell activation

101
Q

CD8+ T cells
- what does it look like and its diagram?

A
  • CD8 + T cells only recognize antigens when they are presented on MHC class 1 molecules
  • When an inactive (naïve) CD8 + T cell interacts with an MHC class 1 molecule and recognized the bound antigen, the T cell becomes primed
  • For full CD8+ T cell activation, it must receive a co-stimulation signal either from the infected cell or from its surrounding
  • Activation stimulates T-cell division and differentia
102
Q

Activated CD8+ T - cells become ?
- What does this looks like?

A

Cytotoxic T cells (Tc) or memory Tc cells
- Lecture #38 page 17

103
Q

Tc cells

A

Directly attack and destroy infected cells by releasing cytotoxic (hence the name, cytotoxic T cells) that enter the infected cell and induce cell death

104
Q

Memory Tc cells

A

are inactive Tc cells that remain in secondary lymphoid organs until a later antigen exposure

105
Q

Regulatory T cells

A

Are CD4+, not CD8+!

106
Q

Activated CD4+ T cells differentiate into?

A

active helper T cells, memory helper T cells, or regularity T cels

107
Q

More about CD4+ T cells
- what does the diagram look like

A
  1. Inactive CD4+ T cells becomes primed after binding and recognizing antigen presented by MHC-2
  2. CD4 + T cell activation required co-stimulation
  3. Activated CD4_ T cells divide and differentiate into helper T cells, memory T cells, or regulatory T cells
  • lecture #38 page 18
108
Q

How does regulatory T cells suppress immune activation?

A

By releasing inhibitory cytokines

109
Q

Sensitization preceded ________
- what is the goal of sensitization?

A
  • B cell activation
  • Goal: coat B-cell surface with target antigen
110
Q

B cell receptors (antibodies)

A

Bind antigens and initiates sensitization

111
Q

B cells endocytose antigen

A

Load them onto MCH- 2 molecule and present them on cell surface

112
Q

What happens when B cell is sensitized?

A

It will await helper T cell interaction for activation
- see the diagram lecture #38 page 19

113
Q

What does B cells require for activation?

A

They need helper T cells for activation

114
Q

Sensitized B cells

A

Search for a helper T cell that has encountered the same antigen

115
Q

What happens upon antigen recognition by the helper T cell receptors?

A

The helper T cell released cytokines to induce B cell activation
- see the diagram on lecture # 38 page 20

116
Q

May circulating helper T cells will attempt to ____

A

Bind the antigen-MHC-2 complex on the sensitized B cell

117
Q

What happens after B cell activation?

A
  • B cells divide and differentiate
118
Q

Inactive memory B cells
- what does this diagram look like?
- it contains Active helper T cell -> activated B cell -> activate B cells -> plasma cells (etc)

A

Located to secondly lymphoid organs until subsequent antigen exposure when they will differentiate into plasma cells and secrete antibodies specific to antigen
Lecture #38 page 21

119
Q

Antibodies
- what does it look like?

A
  • Are small proteins made of plasma cells
  • One antibody consists of 2 parallel polypeptide chains: a heavy chain and a light chain
    -> each chain contains a variable segment and constant segments
    -> the tips of the variable segments form a unique antigen-binding site
    -> when the variable segments bind their target antigen, binding sites on the constant segments are accessible and bind complement protein or innate immune cells
  • lecture #38 page 22
120
Q

What mechanisms does the antibodies use to defend the body from pathogens?
- what does the an antibody look like?

A
  1. Neutralization & preventing adhesion:
    -> antibodies can prevent viral or bacterial infection through physically blocking the pathogen from binding to health cells
  2. Complement:
    -> Binding sites on antibodies bind complement protein which tags the antigen for degradation
  3. Opsonization, phagocytes, and Inflammation:
    -> Antibodies attract phagocytic cells that engulf the pathogen and stimulation release of pro-inflammatory cytokines
  • lecture #38 page 24
121
Q

What are the 5 different classes of antibodies, also called immunoglobulins (lgs)
- what do they all look like?
- how do they differ?

A
  1. lgG: Accounts for 80% of all antibodies and protects against bacteria, bacterial toxins, and viruses
  2. lgA: Found in glandular secretions and mucus membranes and prevent pathogens from accessing internal tissue
  3. lgM: the 1st lg type to be released during infection and circules through blood and lymph
  4. lgE: Associated with allergic reactions and binds mast cells, eosinophils, and basophils
  5. lgD: located on B cells and binds extracellular antigen during sensation

Acronyme: GAMED

  • Look: Lecture #35 page 25
  • Immunoglobulins differ by their heavy-chain constant segments. Therefore, it is possible for a 5 class to react to the same antigens! But immunologically speaking, this is unlikely to actually happen
122
Q

Adaptive immunity improves during ______

A

Subsequent infections

123
Q

Primary Response: first antigen exposure - what does the wave look like?

A
  • antibodies can’t be released until B cells become activated and differentiate into plasma cells
  • antibody titre peaks around 1-2 weeks after intitula antigen exposure
  • lecture # 38 page 26
124
Q

Secondary response: subsequent antigen exposure
- what does the wave look like?

A
  • the infected host already has the necessary tools!
  • memory plasma cells quickly generate antibody titres that far surpass the primary response in both level and time
  • since memory plasma cells can survive for 20+ years, this secondary response will après even if years pass before subsequent antigen exposure
  • lecture # 38 page 26

Immune System (1 decks)

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