Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Immunology > Week 2: Innate Immunity > Flashcards

Week 2: Innate Immunity Flashcards

1
Q

What evokes a response to an infection?

A

When a pathogen breaches our anatomical barriers, innate immune mechanism immediately

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are involved with humoral innate immune response?

A
  1. Antimicrobial enzymes and peptides
  2. Complement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are involved with cellular innate immune response?

A

Innate effector cells
Macrophages
Granulocytes
NK cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the function of macrophages and granulocytes in innate immunity?

A

Recognize, ingest, and destroy pathogens with adaptive response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How fast is innate immunity?

A

Immediately or quickly induced when the host is attacked by a pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is innate immunity?

A
  1. second line of defense are triggered by cell surface or intracellular receptors that recognize microbial carbohydrates, lipids, proteins, and nucleic acids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where are innate receptors located?

A

Macrophages, NK cells, and other innate immune cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does innate receptors recognize?

A

Stress and infected self cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What occurs after phagolytic receptor activation?

A

Lead to phagocytosis and degradation of the pathogen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What occurs after signaling receptor activation?

A

The recruitment of additional innate cells to the infected tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What makes innate immunity non-specific?

A

Exresses many different types of receptors depending on the type of cell
Macrophages recognizes diverse groups of ligands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are pattern recognition receptors (PRRs)?

A

Recognize patterns on microbes and of cellular damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are PRRs found?

A

Innate immune cells (Mac, DC, neu) and on adaptive immune cells (T and B)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the types of innate receptors?

A
  1. C-Type Lectin Receptors (CLRs) (phagocytic receptors)
  2. Toll-Like Receptors (TLRs) (signaling receptors)
  3. NOD-Like Receptors (NLRs) (signaling receptors)
  4. Rig-I-Like Receptors (RLRs) (signaling receptors)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are (PAMPs)?

A

pathogen-associated molecular patterns: Broad structural motifs present on microbes PRRs bind to

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the difference between surface and intracellular PRRs?

A

S: Recognize and bind to extracellular pathogen PAMPs
I: Located in enodsomes/lysosomes and recognize PAMPS that have been endocytose or in the cytosol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where are PRRs located?

A

Extracellular or intracellular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are DAMPs?

A

present on cells that are damaged due to damage, stress or transformation and recognized by PRRs (Damage-associated molecular patterns)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are TLRs?

A

Toll-Like Receptors recognize and bind PAMPs and DAMPs causing immune cells activation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why is cellular location of TLRs important?

A

Allows them to respond to particular ligands

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the difference between extracellular and intracellular TLRs?

A

Extracellular TLRs respond to PAMPS from extracellular pathogens.
Intracellular TLRs primarily respond to viral PAMPs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does activated TLRs induce?

A

Intracellualr signalling pathways that activate transcription factors in producing cytokines and chemotactic factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What pathways are activated by TLRs?

A
  1. NF-κB transcription factor activation
  2. Interferon regulating factor (IRF) pathways
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is the function of NF-κB transcription factor activation?

A
  1. Stimulate production of antimicrobial proteins, peptides, and enzymes
  2. Production of pro-inflammatory cytokines (interleukin-1b (IL-1b) and tumor necrosis factor (TNF-a)
  3. NOD-like receptors also signal through this pathway resulting in IL-1b production
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the function of Interferon regulating factor (IRF) pathways?

A

Pathways used by intracellular TLRs responding to viral PAMPs
Produce and secrete type 1 interferons
Inhibit the replication of viral infected cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What activates NF-κB transcription factor activation and Interferon regulating factor (IRF) pathways other than TLRs?

A

mitogen-activated protein kinases (MAPK) pathway downstream transcription factors such as activator protein 1 (AP-1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is the function of NF-KB and AP-1?

A

Induce expression of pro-inflammatory cytokines and chemokines initiating its production

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What are cytokines?

A

Small soluble proteins that the cells use to affect the behaviors of nearby cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What are chemokine?

A

Type of cytokine that act as chemoattractant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is the function of cytokines?

A

Secreted from the cytokine producing cell and work by binding to the cytokine receptor on the target cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the 3 responses of cytokines?

A
  1. Autocrine (short distances from the cell)
  2. Paracrine (neighboring cells)
    Both limited by distance and life span from collateral damage
  3. Endocrine: more stable cytokines and larger distant cells by entering circulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How does cytokines and chemokine produce a response?

A

When an infection is detected in a tissue, resident macrophages become activated, secrete cytokines to induce inflammation and chemokines that recruit other immune cells to the area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What are the pro-inflammatory cytokines?

A

IL-1, IL-6 and TNF-a

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are the biological effects of IL-1, IL-6 and TNF-a release?

A
  1. Raise in body temperature
  2. Microbes grow slower
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the function ofIL-1, IL-6 and TNF-a on liver?

A

Acute-phase proteins, CRP, MBL to activate complement opsonization

36
Q

What is the function IL-1, IL-6 and TNF-a on bone marrow?

A

Neutrophil mobilization by phagocytosis

37
Q

What is the IL-1, IL-6 and TNF-a on the hypothalamus?

A

Increased body temp decreasing viral and bacterial replication

38
Q

What is the IL-1, IL-6 and TNF-a on fat and muscle?

A

Protein and energy mobilization to generate increased body temp decreasing viral and bacterial replication

39
Q

What iInduces the Acute Phase Response in the Liver Increasing the Supply of Recognition Molecules of Innate Immunity?

A

IL-6

40
Q

How are acute phase proteins formed?

A

Increased response to cytokines produced to infection

41
Q

What are CRPs?

A

Causes opsonination of the pathogen by phagocytic cells, act similar to complement proteins by binding to surfaces on bacteria, fungi, yeast, and parasites

42
Q

What is the clinical use for CRP?

A
  1. Diagnostic indicator of infection
  2. Inflammation
  3. Tissue damage
43
Q

What acute phase proteins recognize pathogens?

A
  1. C-reactive protein
  2. Mannose binding lectin
  3. Lipopolysaccharaide binding protein
44
Q

What acute phase proteins eliminatates pathogens?

A

Complement components C3, C4, C9, factor B

45
Q

What acute phase proteins creates inflammatory response?

A

Cranulocyte colony-stimulating factor, serum amyloid A, secreted phospholipase A2

46
Q

What acute phase proteins causes coagulation?

A

Fibrinogen, plasminogen, tissue plasminogen factor

47
Q

How Do Leukocytes Get to the Site of Infection?

A
  1. Chemokines (IL-8) produced by macrophages recruit neutrophils and other leukocytes to the infected tissue.
  2. Cytokines (IL-1 and TNF-a) increase the expression of adhesion molecules on the endothelium to help move leukocytes from the circulation into the tissues by extravasation.
  3. Neutrophils migrate to the site of infection by following the chemokine (IL-8) gradient.
48
Q

What are the first responders at a site of an infection?

A

Neutrophils

49
Q

What is the most abundant leukocyte?

A

Neutrophils

50
Q

Where do neutrophils come from?

A

recruited from the blood and bone marrow to the infected tissue by inflammatory cytokines

51
Q

What is the function of TNF-a and IL-1B?

A

Increase the permeability of the endothelium allowing neutrophils to access tissues

52
Q

What is the difference between neutrophils and macrophages?

A

N: Short-lived
M: Long-lived

53
Q

What is the function of macrophages?

A
  1. Raise the alarm that an infection is present
  2. Produce inflammatory cytokines and chemokine that bring neutrophils to infected area
54
Q

What happens after neutrophils phagocytose microbes?

A

Forms pus, dies and swallowed by macrophages

55
Q

What are the anti-microbial granules in neutrophils?

A

Primary, secondary, tertiary

56
Q

What are primary granules?

A

Contains substances that disrupt and digest the microbe

57
Q

What are secondary granules?

A

Contain components needed to carry out enzymatic reactions that produce hydrogen peroxide

58
Q

What are tertiary granules?

A

Contain gelatins that restricts the growth of bacteria by sequestering iron

59
Q

What is the function of a virus?

A

Uses the host cell to replicate, transcribe, and translate their genome resulting in a viral nucleic acids in the cytoplasm of human cells

60
Q

What are RIG-I-like receptor (RLRs) and endosomal TLRs?

A

Detect viral RNA/DNA

61
Q

What happens if RIG-I-like receptor (RLRs) and endosomal TLRs are activated?

A

Leads to production of cytokines, specifically type 1 interferons

62
Q

What are the inferno responses?

A
  1. Induce resistance to viral replication in all cells
  2. Increase expression of ligands for receptors on NK cells
  3. Activate NK cells to kill virus-infected cells
63
Q

Where are plasmacytoid dendritic cells (pDC) located?

A

Blood and lymphoid tissues

64
Q

What are plasmacytoid dendritic cells (pDC)?

A
  1. Detects viral infections through TLR7 and TLR9 (intracellular)
  2. Secrete large amounts of type 1 interferon (IFN-a and b) upon TLR induced activation
65
Q

What is the function of IFN?

A

Travels in the blood and lymph and serves to prevent a systemic infection

66
Q

What are the Main Circulating Lymphocyte?

A

NK cells

67
Q

What are NK cells?

A

large and active lymphocytes that respond rapidly to infection, cancer, and cellular stress

68
Q

What is the purpose for NK cells?

A

contribute to the defense against both intra- and extracellular pathogens

69
Q

What is the main functions of NK cells in innate immunity?

A
  1. Kill cells infected with virus
  2. Maintain or increase inflammation in infected tissue
70
Q

How does NK cells kill infected cells?

A
  1. Prevent viral replication
  2. Prevent the spread of the virus to neighboring cells
71
Q

How does NK cells maintain or increase inflammation?

A
  1. Production of inflammatory cytokines
  2. Activate macrophages to secrete cytokines and increase phagocytosis of viral particles
72
Q

What is secreted by infected epithelial cells in response to infection?

A

IFN-a and IFN-b

73
Q

What does IFN-a and IFN-b induce?

A

induce NK cells to proliferate and differentiate into cytotoxic NK cells that will then kill the virally infected cells

74
Q

What does NK cells induce?

A

Induce infected cells to undergo apoptosis by releasing the contents of their granules containing lytic enzymes that cause the infected cell to undergo apoptosis.

75
Q

What happens to apoptotic cells?

A

Cleaned up by macrophages

76
Q

Describe how NK cells and macrophages activate each other?

A
  1. Activated macrophages secrete chemokines that lure NK cells to the site of infection and activate those NK cells.
  2. NK cells can reside in the tissues and enter infected area from the blood following the chemokine gradient.
  3. The macrophage and NK cell form a synapse and IL-12 and IL-15 released from the macrophage cause the NK cell to proliferate and differentiate into an effector NK cell
  4. Effector NK cells then secrete interferon-g (IFN-g)
  5. IFN-g induces macrophages to increase phagocytosis of virus particles and virus infected cells that have been killed by NK cells
  6. IFN-g (type II interferon) is a potent cytokine secreted by NK cells.
  7. Increases phagocytic activity of macrophages.
77
Q

What is the outcome of an innate response?

A

Stimulation of NK cells

78
Q

What is the outcome of an adaptive response?

A

Stimulation of T cells

79
Q

What is the interact between DCs and NK cells during an immune response?

A

DCs take up pathogens by phagocytosis or become infected by the pathogen.

Induces cell-surface receptor changes on DC that are recognized by NK cells

80
Q

What can NK cells recognize?

A

Pathogen induced changes on DCs

81
Q

What does NK cells bind to?

A

DC and leads to the secretion of IL-15 by the DC

82
Q

What is the function of IL-15?

A
  1. induces NK cell to proliferate, differentiate and survive
83
Q

What occurs do to the increase of NK cells?

A

lead to cytotoxic killing of pathogen infected DC

84
Q

What occurs due to the increase in DC numbers?

A

leads to movement of DC to the lymph node to active T cells to initiate adaptive response

85
Q

Resident macrophages are responsible for activating what induced innate responses?

A
  1. Secrete inflammatory cytokines (IL-1, IL-6 and TNF-a) and chemokines (IL-8)
  2. Induce an acute phase response in the liver
  3. Recruit neutrophils, monocytes and NK cells from blood into the tissues
  4. Clean up dead neutrophils at the site of infection
86
Q

What are the cell types that secrete type 1 interferons in response to a viral infection?

A
  1. pDC secrete largest amount of type 1 interferons
  2. NK cells are activated by type 1 interferons, become cytotoxic NK cells that cause infected cells to die by apoptosis
  3. Macrophages induce NK cells to differentiate into effector NK cells that secrete interferon-g
  4. DC and NK interaction will determine if adaptive immune response is activated

Immunology (17 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions