Topic 12 Part 1 Flashcards

1
Q

Immune System=

A

System that protects individual against invasion by microorganisms and foreign substances

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2
Q

Must recognize and destroy invaders–BUT do no damage to normal body tissue:
–destruction by _________
–destruction take place at ________= ability activate and move all components to the site (vascular system / lymphatic system / interstitial fluid)

A

phagocytosis and/or membrane lysis

point of infection

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3
Q

Antigen=

A

–anything foreign that enters the body

–can bind to antibody and/or can bind to receptors on the T or B cells

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4
Q

Target Cell=

A

antigenic cells that will be destroyed by immune system

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5
Q

Immunogen=

A

–any substance that can stimulate an immune response
–all are antigenic (can bind with antibody)
–not all antigens are immunogens

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6
Q

Pathogen=

A

–antigen with ability to cause disease

–usually microorganism or toxin

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7
Q

Microorganism examples

A

bacteria / viruses / parasites / fungi / yeasts

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8
Q

Allogeneic cells=

A

cells from genetically dissimilar individual

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9
Q

Infected Cells=

A

cells inhabited by viruses / certain bacteria / parasites

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10
Q

Leukocytes:
Avg adult has ______ circulating WBCs
NORMAL COUNT: _________

A

75 billion

5,000 to 10,000 per mL

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11
Q
% of Total:
Neutrophiles: 
Lymphocytes (T Cells / B Cells)
Monocytes: 
Eosinophils: 
Basophils:
A
Neutrophiles: 40 to 75% of total
Lymphocytes: 20 to 45%
–T Cells / B Cells
Monocytes: Up to 8%
Eosinophils: 1 to 6%
Basophils: Up to 1%
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12
Q

Granulocytes=

A

Most numerous, named for granules in cytoplasm
–Neutrophils
–Basophils
–Eosinophils

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13
Q

Monocytes=

A

large white cells, become macrophages in body tissues

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14
Q

Lymphocytes: differentiate into

A

B and T cells

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15
Q
Granulocytes: Neutrophils
Made in \_\_\_\_\_\_\_\_
Life span = \_\_\_\_\_\_
\_\_% circulate
\_\_% adhere to blood vessel wall (Margination/Ready to move into tissues)
Fxn: \_\_\_\_\_\_\_\_\_\_
Produce about \_\_\_\_\_\_\_ per day
\_\_\_\_\_\_ micrometer diameter
A
Made in hematopoietic marrow
Life span = hours to days
50% circulate
50% adhere to blood vessel wall (Margination/Ready to move into tissues)
Fxn: phagocytosis
Produce about 100 billion per day
10-15micrometer diameter
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16
Q
Granulocytes: Neutrophils
First to enter \_\_\_\_\_\_\_
Attracted via \_\_\_\_\_\_\_
\_\_\_\_\_\_\_ invading organism
Die
Phagocytized by \_\_\_\_\_\_\_\_
A
First to enter infected areas
Attracted via chemotaxis
Phagocytize invading organism
Die
Phagocytized by macrophages
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17
Q

Granulocytes: Eosinophils
Develop and mature in __________
Appear where __________
Involved in _____________

A

Develop and mature in hematopoietic marrow
Appear where foreign protein and parasites are
Involved in allergic reactions

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18
Q

Granulocytes: Eosinophils

Have binding sites for specific antibodies and complement proteins– Designed to destroy proteins cells coated with (3)

A

IgG antibodies, IgE antibodies and complement

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19
Q
Granulocytes: Eosinophils
Reside in tissues: \_\_\_\_\_\_\_\_\_\_
Release antitoxin (\_\_\_\_\_\_\_\_\_) to destroy organisms
Very effective against \_\_\_\_\_\_\_\_\_
Lifespan = \_\_\_\_\_\_\_
A

Reside in tissues: Skin, bronchi, bronchioles
Release antitoxin (Major Basic Protein) to destroy organisms
Very effective against parasitic worms
Lifespan = 12-24 hours

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20
Q

Granulocytes: Basophils
_____ common
Have _______ and _______ activity
Main fxn : ________

A

Least common
Have chemotaxis and phagocytic activity
Main fxn : release of heparin in areas of foreign invasion to prevent blood clots from forming
–Blood clots–blood can’t circulate- WBC cannot get to foreign organism to destroy–tissue necrosis

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21
Q
Granulocytes: Basophils
Also release \_\_\_\_\_\_ –Causes \_\_\_\_\_\_\_\_\_
Circulate in \_\_\_\_\_\_
Have receptors for \_\_\_\_\_\_\_
Similar to \_\_\_\_ cells: which also contain \_\_\_\_\_, have surface receptors for \_\_\_\_... but Do Not \_\_\_\_\_\_
A

Also release histamine –Causes blood vessel dilation
Circulate in blood
Have receptors for IgE antibody.
Similar to mast cells: which also contain histamine granules, have surface receptors for IgE antibody… but Do Not Circulate

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22
Q
Monocytes / Macrophages:
Produced in \_\_\_\_\_\_\_
Circulate \_\_\_\_\_
Leave the blood and travel to the tissues
–Mature into \_\_\_\_\_\_ -->Actively \_\_\_\_\_\_
–Concentrated in \_\_\_\_\_\_\_\_\_\_
A

Produced in bone marrow
Circulate immature
Leave the blood and travel to the tissues
–Mature into macrophages–>Actively phagocytic
–Concentrated in liver sinusoids, spleen, lungs

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23
Q

Monocytes / Macrophages:
_____ micrometers
Monocytes in blood for ______
Macrophages in tissues for _______

A

12-20 micrometers
Monocytes in blood for 1-2 days
Macrophages in tissues for months to years

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24
Q

Lymphocytes:
Specific immune response when ______ invades
Activated when they recognize _____ matter
Circulate in ____
Wait in ______ for antigens to appear
Play a role in rejection of _______

A

Specific immune response when antigen invades
Activated when they recognize foreign matter
Circulate in blood
Wait in lymph nodes for antigens to appear
Play a role in rejection of organ transplants

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25
Q

T-Lymphocytes (aka. T-Cells):
Mature in ______
Learn to recognize ____
Attack self ______–destroyed

A

Mature in thymus
Learn to recognize self
Attack self tissues–destroyed

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26
Q

T-Lymphocytes (aka. T-Cells):
Membrane receptors on T-Cells bind ________
Need to recognize certain ______ of protein antigens

A

Membrane receptors on T-Cells bind protein antigens

Need to recognize certain fragments of protein antigens

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27
Q

T-Lymphocytes (aka. T-Cells):

Antigen presenting cells (ie. Macrophage) digest and display a _______ on cell surface that T-cells can recognize

A

Antigen presenting cells (ie. Macrophage) digest and display a peptide fragment on cell surface that T-cells can recognize

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28
Q

T-Lymphocytes (aka. T-Cells)
Once T-Cells recognize–bind antigen–Release ______
Different types of T-cells: (4)

A
Once T-Cells recognize–bind antigen–Release cytokines (interleukins)
Different types of T-cells:
Helper T-Cells
Cytotoxic T Cells
Suppressor T Cells
Memory T Cells
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29
Q

Antibody Molecules:

  • Protein molecules: ________
  • Produced by _________ in response to a specific antigen–after initial exposure, takes ___ days to reach full power (lag time)
A
  • Protein molecules: immunoglobulin
  • Produced by B lymphocyte cells (plasma cells) in response to a specific antigen–after initial exposure, takes 14 days to reach full power (lag time)
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30
Q

Antibody Molecules:

  • Always present in _____ amounts–blood & body tissues
  • Five classes:
  • Must bind with the ______ surface of the antigen to be effective–antigen binding site ______
A
  • Always present in small amounts–blood & body tissues
  • Five classes: IgG; IgM; IgD; IgA; IgE
  • Must bind with the outer surface of the antigen to be effective–antigen binding site unique
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31
Q
Antibody Molecules:
-\_\_\_\_\_\_ cross cell membranes
-Functions
–\_\_\_\_\_\_ antigen (mark antigen for destruction)
–activate \_\_\_\_\_\_\_
A

-Cannot cross cell membranes
-Functions
–opsonize antigen (mark antigen for destruction)
–activate complement cascade

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32
Q

Opsonization:
Coating of antigen with ______ and ______
–Provides targeting mechanism for the _____ and ______ allowing them to bind, engulf, and destroy the antigen

A

Coating of antigen with antibody and complement
–Provides targeting mechanism for the phagocytic
neutrophils and macrophages allowing them to bind,
engulf, and destroy the antigen

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33
Q

Opsonization:

Provides points where the ____ can attach to the antigen

A

Provides points where the phagocytes can attach to the antigen

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34
Q

Opsonization:
Phagocytic cells have two specific receptors on their membrane surface
_____ receptor: binds with antibody
_____ receptor: binds with complement

A

Phagocytic cells have two specific receptors on their membrane surface
–Fc receptor: binds with antibody
–C3 receptor: binds with complement

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35
Q

Lysis=

A

–complement activation leads to production of the
membrane attack complex (MAC)
–the MAC will lyse the antigens membrane

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36
Q

Antibody-dependent cell-mediated cytotoxicity:

–cell destruction carried out by _______, _______, _______ and ______ of target cells opsonized by antibody

A

cell destruction carried out by natural killer cells,
macrophages, neutrophils and eosinophils of target
cells opsonized by antibody

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37
Q

Neutralization=

A

antibody renders the antigen toxins harmless

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38
Q

Most antibodies fall into ______ class

A

IgG or IgM

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39
Q

Class determined by the ______ arrangements in heavy and light chains
–same arrangement in specific area of chain

A

amino acid

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40
Q

IgM Antibody Class:

First antibody produced against an antigen by the ____ / plasma cells–increased levels indicate _______

A

First antibody produced against an antigen by the B cells / plasma cells–increased levels indicate new infection

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41
Q

IgM Antibody Class:
First antibody produced by the ____
–increased levels indicate ______ in newborn

A

First antibody produced by the fetus

–increased levels indicate infection in newborn

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42
Q

IgM Antibody Class:
Accounts for _____% of circulating antibody
Very large–remains in _______
Main function to activate ________
Can cause _______
Anti-A and Anti-B antibodies are the _____ type
Fxn: ________

A

Accounts for 10 to 15% of circulating antibody
Very large–remains in vascular system
Main function to activate complement system
Can cause antigen agglutination
Anti-A and Anti-B antibodies are the IgM type
Fxn: Activate Complement

43
Q

IgD Antibody Class:
______ class of antigen to be released
Found only in ___ amounts in ____ and ____ fluids
Has little ______ effect on antigen
May assist with the _______ cells into plasma cells

A

Second class of antigen to be released
Found only in small amounts in serum and body fluids
Has little immunologic effect on antigen
May assist with the maturation of B cells into plasma cells

44
Q

IgE Antibody Class:
____ class of antibodies released
Found in ______ concentrations in plasma
Increases with _____ reactions and _____ infections
–causative agent for ___, _____ and other ______

A

Third class of antibodies released
Found in very low concentrations in plasma
Increases with allergic reactions and parasitic infections
–causative agent for asthma, hay fever and other allergic reactions

45
Q

IgE Antibody Class:
Bind with _____ and _____ cells stimulating them to release ______
Involved with _______ reactions

A

Bind with basophils and mast cells stimulating them to release histamine
Involved with anaphylactic reactions

46
Q

IgG Antibody Class
_____ class released
Most _____ and _____
Comprises __% of antibody in the immune system – produced in greatest amounts on ___ exposure to antigen

A

Fourth class released
Most Important and potent
Comprises 80% of antibody in the immune system – produced in greatest amounts on second exposure to antigen

47
Q

IgG Antibody Class
Only antibody that can ______
–provides immunologic protection for ____
–___ antibody is an IgG antibody
______ disease of the newborn
Very effective at binding and destroying ____

A

Only antibody that can cross the placenta
–provides immunologic protection for fetus
–Rh antibody is an IgG antibody
Hemolytic disease of the newborn
Very effective at binding and destroying antigen

48
Q

IgG1=

A

protects body from (most) bacteria

49
Q

IgG2=

A

attacks and destroys organizms encased in a saccharide coat

Ie. Rest of bacteria

50
Q

IgG3=

A

activates complement proteins

-Enhances phagocytosis of antigen

51
Q

IgG4=

A

produces potent vasodilators

-Protects bronchioles

52
Q

IgA Antibody Class

Major antibody in the body ____ and ____ secreted by the mucous membranes: Such as (4)

A

Major antibody in the body fluids and mucous secreted by the mucous membranes
–tears / breast milk / bronchiole secretions / saliva

53
Q

IgA Antibody Class

  • Binds with antigen to _____ it – allows mucin (main ingredient of ______) to remove antigen-antibody complex
  • Cannot activate the ________
  • Can trigger ________
A
  • Binds with antigen to immobilize it – allows mucin (main ingredient of mucous) to remove antigen-antibody complex
  • Cannot activate the complement system
  • Can trigger cell-mediated immune reactions
54
Q

Biggest antibody? MW?

A

IgM 970

55
Q

antibody with longest half life?

A

IgG (7-21 days)

56
Q

antibody with shortest half life?

A

IgE (2 days)

57
Q

main function of IgM and IgG3

A

activation of complement system

58
Q

main function of IgG1

A

opsonization

59
Q

main function of IgE

A

sensitization of mast cells

60
Q

main property of IgG1 IgG2 IgG3 and IgG4

A

diffusion into extravascular sites

61
Q

main property of IgA

A

transport across epithelium

62
Q

2 main properties of IgG1

A

transport across placenta

diffusion into extravascular sites

63
Q

Immune System
Protects individual against ______
Must ____ and ____ harmful invaders – but do no damage to normal body tissue

A

Protects individual against infectious pathogens

Must recognize and destroy harmful invaders – but do no damage to normal body tissue

64
Q

Two categories of immunity

A

innate

adaptive

65
Q

Innate Immunity
____ / natural
____ line of defense – always present
Able to respond ____

A

Inborn / natural
First line of defense – always present
Able to respond quickly

66
Q

Innate Immunity components (4)

A

epithelial barriers
phagocytes
complement
natural killer cells

67
Q

Innate Immunity:
Uses _____ recognition mechanisms to detect antigen – recognizes _____ – limited number of recognition ___ available
Does NOT produce _____

A

Uses general recognition mechanisms to detect antigen – recognizes microorganisms – limited number of recognition proteins available
Does NOT produce long term immunity to antigen

68
Q

innate immunity is responsible for

A

inflammation

69
Q
Adaptive Immunity:
Responds to \_\_\_\_\_ antigen
–can be \_\_\_\_\_\_\_
– \_\_\_\_\_ of recognition proteins
Develops after \_\_\_\_\_\_
A

Responds to specific antigen
–can be non microbial
–millions of recognition proteins
Develops after exposure to antigen

70
Q

Adaptive Immunity:
_____ response
Produces very _____ response
_______ are the major players

A

Slow response
Produces very powerful response
Lymphocytes (T & B cells) are the major players

71
Q

Characteristics of Adaptive Immunity: Specificity=

A

immune reaction specific for offending antigen

72
Q

Characteristics of Adaptive Immunity: Diversity=

A

lymphocytes can respond to millions of antigens

73
Q

Characteristics of Adaptive Immunity: Memory=

A

lymphocytes can remember any antigen previously encountered

74
Q

Characteristics of Adaptive Immunity: Self-regulation=

A

lymphocytes can shut down activity after antigen is destroyed

75
Q

Characteristics of Adaptive Immunity: Self-tolerance=

A

lymphocytes can distinguish self-tissue from non self tissue

76
Q

Immune response initiated when ____ stimulates activation of ____ cells

A

antigen

T and B

77
Q

Phases of response: cognitive phase=

A

(first phase)

antigen interacts with the T lymphocytes

78
Q

Phases of response: activator phase=

A

(second phase)
T cells respond by releasing cytokines
cytokines stimulate proliferation of T & B cells

79
Q

Phases of response: effector phase=

A

(third phase)
granulocytes / macrophages / complement activated
antigen opsonized and engulfed

80
Q

T Lymphocytes:
____ immune response against ____ antigen
Responsible for the ____ cells that respond and how they respond

A

Direct immune response against protein antigen

Responsible for the type of white cells that respond and how they respond

81
Q

T Lymphocytes:

  • T cells must recognize the _____
  • T cell response to antigen is called _____
A

T cells must recognize the antigen

T cell response to antigen is called CELL-MEDIATED IMMUNITY

82
Q

Role of T Cells

  • Direct _______
  • Assist _____ via release of _____ that activate other phagocytic cells
  • Destroy ____ cells, ___ cells and ____ cells via lysis
A
  • Direct immune response
  • Assist phagocytosis via release of cytokines that activate other phagocytic cells
  • Destroy malignant cells, allogeneic cells and infected cells via lysis
83
Q

Role of T Cells

  • Aid ____ / ____ cells in antibody production
  • Involved with delayed_______
  • Cause some types of _____ in organ and tissue transplantation
  • Responsible for certain types of _______
A
  • Aid B cells / plasma cells in antibody production
  • Involved with delayed hypersensitivity immune reactions
  • Cause some types of graft rejection in organ and tissue transplantation
  • Responsible for certain types of autoimmune disorders
84
Q
T Cell Production:
Produced in \_\_\_\_\_\_
Mature in \_\_\_\_\_\_
–cells trained to distinguish \_\_\_\_\_\_
Leave thymus – travel to secondary lymphatic organs (3)
A

Produced in bone marrow
Mature in thymus
–cells trained to distinguish self-tissue from non self-tissue
Leave thymus – travel to secondary lymphatic organs
–lymph nodes
–spleen

85
Q

Types of T Cells: Categorized by? Types of them?

A

protein molecules on cell membrane (i.e. CD8+ / CD4+)

  • cytotoxic cells
  • helper cells
  • suppressor cells
86
Q

What type of molecules bind to CD8

A

MHC Class 1

87
Q

What type of molecules bind to CD4

A

MHC Class 2

88
Q

what are CD8 cells

A

Cytotoxic T Cells

89
Q

what are CD4 cells

A

Helper T Cells

90
Q

Cytotoxic T Cells:

  • Must be converted from ______
  • Destroy (3)
  • Once activate, release _____ that rupture target cells
A
  • Must be converted from inactive T cells
  • Destroy virally infected cells, allogenic cells (organ transplant), malignant cells
  • Once activate, release lytic molecules that rupture target cells
91
Q

Helper T Cells:
Assist or activate other white cells–release _____ to call other cells
Do not destroy ______

A

Assist or activate other white cells–release cytokines to call other cells
Do not destroy antigen directly

92
Q

Helper T Cells:

Activated when presented with

A

antigen-MHC combination

93
Q

Helper T Cells: what is MHC

A

MHC is major histocompatibility complex

  • found on most body cells
  • divided into Class I or Class II
  • binds with antigen fragments
94
Q

Helper T Cells: TH1=

A

inflammatory helper; releases cytokines that convert inactive T cells into cytotoxic T cells

95
Q

Helper T Cells: TH2=

A

release cytokines needed for B cell activation and antibody secretion; MUST be present

96
Q

Suppressor T Cells

Activated to ______ response once antigen has been destroyed

A

stop immune

97
Q

B Lymphocytes
Produce antibody in response to antigen–called ____
Able to directly recognize ____ and ____ antigens and initiate response

A

Produce antibody in response to antigen–called HUMORAL IMMUNITY
Able to directly recognize carbohydrate and lipid antigens and initiate response

98
Q

B Lymphocytes

Must be activated by ____ before it can produce antibody against protein antigen

A

TH2 helper cells

99
Q

B Lymphocytes
When activated: proliferate and differentiate into plasma cells
–plasma cells produce the _____ for the specific antigen
–antibody will be produced until ______

A

When activated: proliferate and differentiate into plasma cells
–plasma cells produce the antibodies for the specific antigen
–antibody will be produced until antigen has been destroyed

100
Q

How they all play together: Part 1

  1. ____ antigen is present
  2. Ingested by ____ cells (in skin) –Antigen is digested to _____
  3. ____ cell moves to the _____
  4. Digested protein bound into a groove on the____ on surface of ______ cell
A
  1. Protein antigen is present
  2. Ingested by dendritic cells (in skin) –Antigen is digested to small peptides
  3. Dendritic cell moves to the lymph node
  4. Digested protein bound into a groove on the MHC molecule on surface of dendritic cell
101
Q

How they all play together: Part 2
5. Finds a ____ (naïve – hasn’t interacted with other antigens)
–If T-Cell Receptor (TCR) of CD4 T-Cell sees a ____ it recognizes -> Becomes ____ -> divides and releases ____
–Help induce a ____ to make antibodies

A
  1. Finds a CD4 T-cell (naïve – hasn’t interacted with other antigens)
    –If T-Cell Receptor (TCR) of CD4 T-Cell sees a peptide it recognizes -> Becomes active -> divides and releases cytokines
    –Help induce a B-cell to make antibodies
102
Q

How they all play together: Part 3
6. Meanwhile – antigen is also recognized by naïve B-cells with _____ molecule
–_____ binds to immunoglobulin on B-Cell.
–Ingested and digested by _____
–____ present on surface of B-Cell in ____ molecules
–React with activated _____: Make _____

A
  1. Meanwhile – antigen is also recognized by naïve B-cells with immunoglobulin molecule
    –Antigen binds to immunoglobulin on B-Cell.
    –Ingested and digested by B-Cell
    –Peptide present on surface of B-Cell in MHC molecules
    –React with activated T-Cell: Make Antibodies
103
Q

How they all play together: Part 4
7. CD4 cell recognized antigen peptide on dendritic cell will recognize peptide present on the ____.
–CD4 cell is ____ –Capable of releasing _____: Stimulate the B-cells to make _____
–Activated CD4 cell with MHC-peptide on B-cells will induce B-cells to become ____: Proliferate and release ______

A
  1. CD4 cell recognized antigen peptide on dendritic cell will recognize peptide present on the B-cell.
    –CD4 cell is activated –Capable of releasing cytokines: Stimulate the B-cells to make Antibodies
    –Activated CD4 cell with MHC-peptide on B-cells will induce B-cells to become activated: Proliferate and release antibodies
104
Q

How they all play together: Part 5
8. B-cells have ____ marker on cell surface
9. CD4 cells (activated helper) have a _____
–Transient presence
10. Appears on T-cells after ____ binds to antigen
11. CD40 : CD40L = ______

A
  1. B-cells have CD40 marker on cell surface
  2. CD4 cells (activated helper) have a ligand CD40L
    –Transient presence
  3. Appears on T-cells after TCR binds to antigen
  4. CD40 : CD40L = costimulation
    –Need Co-stimulation to make antibodies