Immunology week 2 Flashcards

1
Q

Organization of the Immune System
2 catagories, what are they?

A

Innate immunity-first line of defense (non-specific)
Adaptive immunity-second line of defense (specific)

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2
Q

what are the 2 types of innate immunity?

A

cellular component
humoral component

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3
Q

what are teh 2 types of adaptive immunity?

A

humoral component and cellular component

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4
Q

The Immune System

Innate Immunity
what is the requirement of prior contact with the AG?

A

Protects the body from injury
without prior contact with an
AG

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5
Q

The Immune System
Innate Immunity
rapid or slow?

A

Rapid

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6
Q

The Immune System
Innate Immunity

what is the timing for immediate?

A

● Immediate: 0-4 hrs

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7
Q

The Immune System
Innate Immunity
what is the timing for induced?

A

● Induced 4-96 hrs

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8
Q

The Immune System
Innate Immunity
with induced is there memory?

A

● Induced 4-96 hrs
○ NO MEMORY

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9
Q

The Immune System
Innate Immunity
● Induced

what are the 3 types of barriers?

A

● Physical barriers
● Humoral barriers (complement)
● Cellular barriers

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10
Q

The Immune System
Adaptive
rapid or slow?

A

● SLOW

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11
Q

The Immune System
Adaptive

relationship to AG?

A

● Response to AG

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12
Q

The Immune System
Adaptive
Is memory present?

A

● Memory is present

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13
Q

The Immune System
Adaptive
does it require exposure to the AG

A

● Requires exposure to AG

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14
Q

The Immune System

what happens after the body when exposed to hundreds of billions of microbes?

A

Barriers:

mechanical
chemical
biological
(first line of defense)

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15
Q

The Immune System

Barriers:

mechanical
chemical
biological
(first line of defense)

what happens next inside the body?

A

2nd line of defense
innate immune system

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16
Q

The Immune System
2nd line of defense
innate immune system
what happens next within the body?

A

Addaptive immune system
3rd line of defense

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17
Q

Innate Immunity- present from birth!
what are the physical barriers?

A

● Physical barriers- skin & mucosal areas

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18
Q

Innate Immunity- present from birth!
● Physical barriers- skin & mucosal areas

what are the 3 catagories?

A

○ Mechanical factors: mechanically remove infectious microbes & prevents invasion
○ Chemical
○ Microbiological

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19
Q

Innate Immunity- present from birth!
● Physical barriers- skin & mucosal areas
○ Mechanical factors: mechanically remove infectious microbes & prevents invasion
5 examples:

A

■ Skin
■ Ciliary movement
■ Peristaltic movement
■ Flushing
■ Mucus

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20
Q

Innate Immunity- present from birth!
● Physical barriers- skin & mucosal areas

○ Chemical
4 examples and what they do:

A

■ Fatty acids- inhibit growth of bacT
■ lysozyme & phospholipase- inhibit growth of pathogens
■ Low pH- antibacT effects
■ Surfactants-enhance phagocytosis

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21
Q

Innate Immunity- present from birth!
● Physical barriers- skin & mucosal areas
○ Microbiological
what is it and what does it do?

A

■ Normal biota prevents infection by secreting inhibitory substances

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22
Q

Innate Immunity
● Humoral barrier has 6 defense mechanisms: complement system, coagulation system, lactoferrin, lysosome, interferon and interleukin. How do each help?

A

Innate Immunity
● Humoral barrier- complement system
○ Complement system- enzymes/ proteins that prevent infections
○ coagulative system- blood coagulation to prevent pathogen entry also can be a
chemotactic
○ Lactoferrin & transferrin- sequesters iron
○ Lysozyme- digests the bacterial cell wall
○ Interferons
■ Type 1= inhibit infection and replication of viruses

○ Interleukin 1- increase temp to induce acute phase proteins

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23
Q

Innate Immunity
● Humoral barrier- complement system

what is Complement system-

A

enzymes/ proteins that prevent infections

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24
Q

Innate Immunity
● Humoral barrier- complement system

what is coagulative system-

A

blood coagulation to prevent pathogen entry also can be a
chemotactic

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25
Innate Immunity ● Humoral barrier- complement system what is Lactoferrin & transferrin-
○ Lactoferrin & transferrin- sequesters iron
26
Innate Immunity ● Humoral barrier- complement system what is Lysozyme
○ Lysozyme- digests the bacterial cell wall
27
Innate Immunity ● Humoral barrier- complement system what is **Interferons**
**○ Interferons ■ Type 1= inhibit infection and replication of viruses**
28
Innate Immunity ● Humoral barrier- complement system what is Interleukin 1
○ Interleukin 1- increase temp to induce acute phase proteins
29
Innate immunity ● Cellular barrier what is it?
● Cellular barrier- phagocytic system & NK cells
30
Innate immunity ● Cellular barrier- phagocytic system & NK cells Neutrophils-what are they?
phagocytose microorganisms
31
Innate immunity ● Cellular barrier- phagocytic system & NK cells Macrophages-what do they do? what do they possess, what dont they possess?
Macrophages-ingest & kill micros intracellularly, phagocytosis, APC, aid in wound healing (respond to the SOS) ■ They do not possess granules but they have lysosomes that contain factors required for intracellular killing mechs
32
Innate immunity ● Cellular barrier- phagocytic system & NK cells NK- what does it do?
○ NK- kill infected/ tumor cells
33
Innate immunity ● Cellular barrier- phagocytic system & NK cells Eosinophils-what do they do?
Eosinophils- eliminate parasites
34
Innate immunity ● Cellular barrier- phagocytic system & NK cells Name 4 types of cells
Innate immunity ● Cellular barrier- phagocytic system & NK cells ○ **Neutrophils**- phagocytose microorganisms ○ **Macrophages**-ingest & kill micros intracellularly, phagocytosis, APC, aid in wound healing (respond to the SOS) ■ They do not possess granules but they have lysosomes that contain factors required for intracellular killing mechs ○ **NK-** kill infected/ tumor cells ○ **Eosinophils**- eliminate parasites
35
what are the 4 most important cells of the innate immuniyt?
Neutrophils macrophages dendritic cells natural killer cells
36
the most important cells of the innate immunity? Neutrphils what is the function?
Phagochtosis Reactive oxygen and nitrogen species antimicrobial peptides
37
the most important cells of the innate immunity? Macrophages what is the function?
phagocytosis inflammatory mediators antigen presentation reactive oxygen and nitrogen species cytokines complement protiens
38
the most important cells of the innate immunity? Dendritic cells what is the function?
antigen presentation costimulatory signals reactive oxygen species interferon cytokines
39
the most important cells of the innate immunity? natural killer cells what is the function?
Lysis of viral-infected cells interferon macrophage activation
40
NB cells for phagocytosis ● Neutrophils 5 facts: are they numerous? immature=? what do they do, where do they hang out, why? How do you ID? how many types of granules?
● Neutrophils ○ Most numerous innate cell ○ immature=banded neutrophils ○ Circulate in the BS looking for things to eat :) ○ ID by expression of CD66 ○ Contain 2 types of granules ■ Azurophilic ● Defensins ● Proteolytic enzymes ● Lysozyme ●** Myeloperoxidase** ■ Secondary granules ● Lysozyme ● Lactoferrin ● NADPH oxidase components (toxic radicals)
41
NB cells for phagocytosis ● Neutrophils what are the 2 types of ganules called?
Azurophilic Secondary granules
42
NB cells for phagocytosis ● Neutrophils ○ Contain 2 types of granules ■ Azurophilic 4 examples are:
■ Azurophilic ● Defensins ● Proteolytic enzymes ● Lysozyme ● **Myeloperoxidase**
43
NB cells for phagocytosis ● Neutrophils ○ Contain 2 types of granules ■ Secondary granules 3 examples are?
■ Secondary granules ● Lysozyme ● Lactoferrin ● NADPH oxidase components (toxic radicals)
44
NB cells for phagocytosis ● Macrophages 3 facts: How do you ID? What don't they possess, what do they have, why? what do they react to, how?
● Macrophages ○ ID by expression of CD14,Cd11b, F4/80 ○ Do not possess granules but have lysosomes that contain factors required for intracellular killing mechs ○ React to SOS signals that induce chemotaxis of macs towards the site of microbe entry
45
Phagocytosis- background info What are phagocytes? what do they have? what do they do? why?
● phagocytes= have many receptors that they can bind to microbes with to eat them
46
Phagocytosis- background info ● phagocytes what are teh 4 kids of receptors?
1. Complement receptor 2. Scavenger receptors 3. Fc receptors 4. Toll-like receptors TLR
47
Phagocytosis- background info What are complement receptors and what do they do?
1. Complement receptors=C3b a. Binds to the AG then AG binds to the phagocyte
48
Phagocytosis- background info What are Scavenger receptors and what do they do?
Scavenger receptors= SRA,CD68,Lox-1, CD36 bind directly to polyamines (on bacT surface)
49
Phagocytosis- background info what are Fc receptors and what do they do?
Fc receptors- on macs bind to the FC regions on Ab that are bound to AG
50
Phagocytosis- background info Toll-like receptors TLR what do they do?
Toll-like receptors TLR- Recognize PAMPS
51
Phagocytosis- background info What is the definition and what are the 4 functions?
Def: active process of capturing and ingesting foreign objects/ microbes by phagocytes (ex neutrophils and macs) ○ Detects and destroys microbes ○ Removes damaged cells & foreign objects ○ Induce productions of cytokines for inflammation ○ Process and present AG to induce IR
52
Phagocytosis what are the 2 ways various receptors bind to microbes?
Phagocytes have various receptors to bind to microbes directly or through opsonization (basically marks the pathogen to induce phagocytosis)
53
Phagocytosis- explain direct recognition?
● **Direct recognition is performed by PRR recognizing PAMPS**
54
Steps of phagocytosis what are the 7 steps?
1. Chemotaxis move towards the target/phagocytes move toward SOS signal 2. Phagocytes detect and bind to said target/object through appropriate receptors 3. They surround the captured object with pseudopodia and engulf objects through endocytosis 4. EndocytosedObject is enclosed in the phagosome 5. Phagosome + lysosome= phagolysosome 6. Lysosome releases its contents in the phagolysosome 7. Digestion of the endocytosed object
55
Steps of phagocytosis Example beginning with Bacterium becoming attached to the membrane evaginations called Pseudopodia...next?
Bacterium is ingested forming phagosome phagasome fuses with lysomsome lysosomal enzyme digests captured material digestion products are released from cell
56
Process of Phagocytosis (more detailed) purpose:
*Purpose: DETECT and DESTROY microorganisms, REMOVE damaged cells and foreign objects, INDUCE cytokines, PROCESS and PRESENT antigens and induce immune response
57
The 2 killing pathways
● Oxidative pathway ROS and RNS ● Non-oxidative (enzymatic)
58
The 2 killing pathways ● Oxidative pathway ROS and RNS ● Oxygen dependent intracellular killing explain ROS what happens? how is it activated? what is the result? how did it occur?
○ ROS ■ Glucose->NADPH ■ NADPH-> activated by cytochrome oxidase ■ Result: superoxide anion ■ Basically the reactive O2 spp. will change the chemical structure of the cell and the bacT will be destroyed.
59
The 2 killing pathways ● Oxidative pathway ROS and RNS ● Oxygen dependent intracellular killing ○ RNS what result?
○ RNS ■ Results in cell death
60
The 2 killing pathways ● Oxidative pathway ROS and RNS ● Oxygen dependent intracellular killing ○ Myeloperoxidase dependent killing what is it?
○ Myeloperoxidase dependent killing ■ essentially using bleach (hypochlorous acid) to kill bacT w/n the neutrophil
61
The 2 killing pathways ● Non-oxidative (enzymatic) how does this occur? (4 steps)
● Non-oxidative (enzymatic) ○ Cationic proteins- damage bacT cell wall ○ Lysozyme- damages mucopeptides in cell wall ○ Lactoferrin- sequesters iron ○ Proteolytic/ hydrolytic enzymes- digest killed bacT
62
Pathogen recognition ● Sentinel cells what are they?
● Sentinel cells= DC, Macs, Mast cells
63
Pathogen recognition ● Sentinel cells= DC, Macs, Mast cells what do they contain? what do they do?
○ Contain Pattern Recognition Receptors(PRR) which will be able to recognize PAMPS and DAMPS
64
Pathogen recognition ● Sentinel cells= DC, Macs, Mast cells ○ Contain Pattern Recognition Receptors(PRR) which will be able to recognize PAMPS and DAMPS what are PAMPS? how are they expressed?
○ PAMPS- expressed by microbes and not host tissue
65
Pathogen recognition ● Sentinel cells= DC, Macs, Mast cells ○ Contain Pattern Recognition Receptors(PRR) which will be able to recognize PAMPS and DAMPS What are DAMPS? where do they come from?
○ DAMPS- released by damaged host cells
66
Pathogen recognition ● Sentinel cells= DC, Macs, Mast cells ○ Contain Pattern Recognition Receptors(PRR) which will be able to recognize PAMPS and DAMPS ○ PAMPS- expressed by microbes and not host tissue ○ DAMPS- released by damaged host cells ○ There are 5 types of PRR, what are they?
■ Toll- like TLR ■ NOD like- NLR ■ RIG Like- RLR ■ C-type lectin CLR ■ Peptidoglycan- recognition proteins
67
PRR ● Toll-like where are they located? how are they signaled? what is the final result?
● Toll-like ○ Located on host cell membranes or within the host cells ○ Signal through MyD88 except TLR3 TRIF and TLR4 can do both ○ The end game: proinflammatory cytokine production
68
PRR ● NOD- like what do they do, how? what can it lead to?
● NOD- like ○ Detects intracellular pathogens via either PAMPS or DAMPS ○ Detection of PAMPS= activation of transcription factor NF-kB (**very important will come back again**) which results in expression of proinflammatory cytokines ○ Can also lead to production of type 1 interferons
69
PRR ● RIG- like what do they detect? how? what do they do?
● RIG- like ○ Detect VIRUSES (viral RNA) ○ Induce production of type 1 interferons and imflam. Cytokines
70
PRR ● C- type Lectin what is an example? why is it important?
● C- type Lectin ○ Think fungi! ○ Side note: th17= is important for fungal infections as well
71
PRR ● Peptidoglycan recognition proteins examples? where are they found? what do they produce?
● Peptidoglycan recognition proteins ○ NAG/NAM ○ Localized in granules of neutrophils (acute bacT infection) ○ Produces defensins- antimicrobial peptides
72
Receptors what are the 4 kinds?
● Scavenger receptors ● Toll-like receptors ● Fc receptors ● Complement
73
Receptors ● Scavenger receptors what do they do? examples?
● Scavenger receptors ○ directly bind to polyamines on bacT surfaces ○ SRA, CD68, Lox-1, CD36
74
Receptors ● Toll-like receptors where are they located? what do they do? what happens?
● Toll-like receptors ○ On the cell membrane or within the cell ○ Recognize PAMPS & DAMPS ○ Aid in secretion of inflammatory cytokines
75
Receptors ● Fc receptors what happens? what does it require?
● Fc receptors ○ When a phagocyte binds to the Fc region of an AB it enhances the metabolic activity of the phagocyte ○ Requires AB!
76
Receptors ● Complement what happens, what result? **see slide to small to read.
● Complement ○ C3b binds to the AG which then results in phagocytosis
77
Natural Killer cells What are NK cells?
They kill infected or tumor cells
78
What are NK cells? what are they also known as and what do they contain?
● Aka large granular lymphocytes (LGL) and contain granules
79
What are NK cells? where do they originate?
● Origin: bone marrow
80
What are NK cells? where are they located?
● Location: blood, spleen, liver
81
What are NK cells? Do they migrate? when?
● Migrate in lg #’s when inflammatory rxn is occurring
82
What are NK cells? Do they have AG specific receptors?
**● No AG specific receptors like t&b cells**
83
What are NK cells? what do they do?
● Recognize and kill virally infected or cancer cells
84
What are NK cells? what do the granules do?
● Contain granules which induce apoptosis
85
What are NK cells? what 2 types of immunity do they aid in?
**● Nkt cells aid in both innate and adaptive immunity**
86
What are NK cells? Humans & mice=?
● Humans & mice= express CD56, CD16 and LACK CD3
87
What are NK cells? ● Pigs=?
● Pigs= no exclusive marker
88
What are NK cells? Cattle & Horses=?
Cattle & Horses= CD335
89
NK Functions Innate immunity what are the 2 functions?
Innate immunity ○ Killing stressed/ infected/ tumor cells= “abnormal” ■ abnormal= no MCH1 and/ or express stress signals too ○ Aid in cytokine and chemokine production
90
NK Functions Innate immunity ○ Killing stressed/ infected/ tumor cells= “abnormal” what is “abnormal”
■ abnormal= no MCH1 and/ or express stress signals too
91
NK Functions what do inhibitory signals recognize? where?
**● Inhibitory signals recognize MHC1 molecules found on ALL NORMAL nucleated cells**
92
NK Functions what are activating receptors examples?
****● Activating receptors- bind to stressed/ infected/ tumor cells (ex. MICA & MICB)
93
NK Functions how are they regulated?
● Nk cells are regulated by a balance between activating and inhibitory signals ○ Inhibitory signal is dominate
94
NK Functions how are they regulated? which signal is dominant activating or inhibitory?
Nk cells are regulated by a balance between activating and inhibitory signals **○ Inhibitory signal is dominate**
95
NK Functions ● KIRs=?
● KIRs= humans, cattle, cats, dogs,& pigs
96
NK Functions ● KIRs= humans, cattle, cats, dogs,& pigs explain: 3 facts they are highly.. how are they expressed?
● KIRs= humans, cattle, cats, dogs,& pigs ○ Highly polymorphic ○ LILRs= expressed on NK cells & leukocytes ○ NKp46= e**xpressed only by NK cells!**
97
NK Functions ● KLRs=
● KLRs= mice, rates,& horses
98
● KLRs= mice, rates,& horses what do they express? how is it recognized? what result?
● KLRs= mice, rates,& horses ○ NK express NKG2D which recognizes MICA & MICB and results in apoptosis ○ NKG2D is also on gamma delta t cells (will talk about later)
99
NK Functions In virto NK cells are activated by what? what do they become? how are they used?
● Side note:(will touch on again later) ○ In virto NK cells activated by IL2 and INFy become lymphokine activate killer cells (LAK) which are cutotoxic cells and can be used in immunotherapy
100
How do they know who to kill & how do they kill? ● Abnormal cells most of the time they don't express much ? what do they express? what result?
● Abnormal cells ○ Most of the time don’t express MCH1 ○ Also express stress signals like MICA and MICB ● Results in killing of the abnormal cell
101
How do they know who to kill & how do they kill? ● Normal cells How are they different?
● Normal cells ○** Strong inhibitory signals** ■ Normal MCH1 and absence of stress hormones
102
How do they know who to kill & how do they kill? what signal is dominent? why does that matter?
**Inhibitory signals are dominant and will result in a do not kill signal**
103
How do they know who to kill & how do they kill? ● Perforin dependent- innate what happens? what result? what does this induce?
● Perforin dependent- innate ○ Perforin granules are released ○ It creates a hole in the cell ○ Granzymes & proteases enter through the hole ○** Induces apoptosis**
104
How do they know who to kill & how do they kill? ● Fas/ FasL CD95/ CD95L- innate what is expressed, by who? what result?
● Fas/ FasL CD95/ CD95L- innate ○ NK express CD95L and abnormal cells express CD95 (death receptor) and will result in apoptosis
105
How do they know who to kill & how do they kill? ● CD16 pathway ADCC-adaptive what is responding to what, how?
● CD16 pathway ADCC-adaptive ○ NK will respond to an AB that is responding to an AG using CD16 (Fc receptor)
106
ADCC 1-antibody binds what? where? 2-what do the FC receptors do? 3-cross-linking of what, signals what? 4-what happends to the target cell, how?
1-antibody binds antigen on the surface of teh target cell 2- fc reseptors on NK cell recognise bound antibody 3-cross-linking of Fc receptors signals the NK cell to kill the target cell 4-target cell dies by apoptosis
107
ADCC Its NB to know that target recognition through ? only occurs when ? are present?
**Its NB to know that target recognition through CD16 only occurs when AB are present ;)**
108
Regulation of NK cells what are they activated by?
*Activated by IL-1, IL-2, IL-12, IL-15, IL-18, IL-21, and type 1 and 2 interferons
109
Regulation of NK cells are they In vitro?
*In vitro
110
Regulation of NK cells *Activation via above= what turns to what which result in what?
*Activation via above=Nk cells turn into LAK (lymphokine activated killer cells) which have increased cytotoxic capacity
111
Regulation of NK cells what can LAK be used for?
*LAK can be used for tumor immunotherapy
112
Regulation of NK cells what does *LAK—>
*LAK—>highly cytotoxic cell
113
NK subtypes 4 what are they?
● NK T cells ● NK cells that are similar to t lymphocytes ● NK DCs ● DC that are similar to NK cells
114
NK subtypes ● NK cells that are similar to t lymphocytes origin? express? specific to what? what are they made of? How are they activated? what do they link? examples (4)?
● NK cells that are similar to t lymphocytes ○ From thymic origin ○ Express and invariant alpha beta TCR ○ Only specific to a few pathogens ○ They are CD4+ cells ○ Activated by IL-15 ○ Link the t cell system and NK cells ○ **Allergies, antitumor immunity, autoimmunity, and antimicrobial immunity roles**
115
NK subtypes ● DC that are similar to NK cells spontaneously what? can present to ? produce what? link what?
● DC that are similar to NK cells ○** Spontaneously lyse tumor cells** ○ Can present to naive T cells ○ Produce larger amounts of INFy ○ **Link innate and adaptive immunity**
116
Which of the following is NOt one of the most important cells of innate immunity? A. Mast Cells B. B. NK cells C. Neutrophils D. Macrophages
A
117
Which of the following is a first line of defense? A.Antibodies B.Complement System C.Phagocytosis D.Sweat
D
118
Which of the following Phagocytosis receptors require AB? A.Fc receptors B.Scavenger Receptors C.Toll Like Receptors D.Complement Receptors
A
119
DIn which of the following do endocytosed material occur during phagocytosis? A.Pseudopodia B.Phagosome C.Endocytosis D.Phagolysosome
D
120
Which of the following is true regarding a malfunctioning phagocytic system? A.Increase in adaptive immunity B.Increased inflammatory response C.Increased infection rate D.Increased detention and destruction of pathogenic microorganisms
C
121
Which of the following PRR binds for viral recognition? A.RIG-like receptors B.NOD-like receptors C.C-type Lectin receptors D.Peptidoglycan-recognition receptors
A
122
Which of the following is released by NK cells to activate macrophages? A.Cytokines B.IL-17 C.IFN gamma D.Angel Stop asking me these things
C
123
If a NK cell were to come upon this cell, the NK cell would induce apoptosis. True or False? A.True B.False
B
124
Activating signal is the dominant signal for NK cells. A.True B.False
B
125
Which of the following NK cell pathways works by creating a pore in the target cell and releasing enzymes to induce apoptosis? A.Perforin-dependent Pathway B.Fas/FasL Binding C.CD16/ADCCC D.Idk man
A
126
What is the end result of the FAs/ FAsl pathway? Follow up : what is another name for this pathway? A. It results in activating the adaptive immune system B. Bpoptosis C. It aids in the cells replicating rapidly D. Apoptosis
D