Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Immuno Exam 3 > Lecture 22 > Flashcards

Lecture 22 Flashcards

1
Q

Allergy

A

altered immunological state induced by an antigenic substance resulting in pathological reactions on subsequent encounter with that antigen (or similar antigen), Type I hypersensitivity or hypersensitivity

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

Allergen

A

an antigen that stimulates IgE-mediated reactions (pollen, dust, animal dander)

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

Asthma

A

chronic occluding disease of small and large airways of the lungs that is immunologically mediated. Allergic or non-allergic (Gamma/delta TCR and eosinophils play a significant role)

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

Atopy

A

susceptibility of certain individuals to natural sensitization by environmental allergens (pollen, spores, foods)

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

Sensitization

A

the process of inducing a an immune response resulting in an untoward effect - for Type I hypersensitivities it is production go IgE

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

Hypersensitization

A

adapted immune response that occurs in an exaggerated or inappropriate form, causing damage and/or aberrant physiological functions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Anaphylaxis

A

adverse response provoked by an allergen, which results in vasodilation and smooth muscle relaxation in the periphery and constriction of smooth and opposite effect on smooth muscle of the bronchus and GI tract

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

Body regions with IgE localization

A

skin, respiratory and GI tract

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

Mast cell localization

A

fixed tissue near blood vessels in skin, CT, linking of gut and lungs

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

Influencers of Atopy

A

propensity of allergen, route of exposure, genetics, age

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

Type 1 Immediate Hypersensitivity - anaphylaxis Immune Pathologic Mechanism

A

IgE

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

Type 1 Immediate Hypersensitivity - anaphylaxis includes activation of which cells?

A

Mast cells, basophils, eosinophils

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

Type 1 Immediate Hypersensitivity - anaphylaxis includes which mediators

A

histamine, other vasoactive amines, arachidonic acid metabolites, cytokines

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

Type 1 Immediate Hypersensitivity - anaphylaxis includes release of

A

Oxygen and nitrogen radicals, proteases, etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Examples of Type 1 Immediate Hypersensitivity - anaphylaxis include

A

Hay fever, asthma

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

Type 1: Immediate Hypersensitivity - anaphylaxis occurs within _____________ of exposure

A

15 min

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

Type II: Antibody-mediated cytotoxic or cytolytic reaction Pathological Mechanism

A

IgM, IgG antibodies against tissue or cell surface antigens

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

Type II: Antibody-mediated cytotoxic or cytolytic reaction includes activation of which cells?

A

leukocytes (neutrophils and macrophages)

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

Type II: Antibody-mediated cytotoxic or cytolytic reaction includes an abnormality in…

A

receptor function

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

Type II: Antibody-mediated cytotoxic or cytolytic reaction includes activation of?

A

complement, leukocytes (macrophages and neutrophils)

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

Examples of Type II: Antibody-mediated cytotoxic or cytolytic reaction include

A

transfusion reactions, hemolytic disease of the newborn

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

Type III: Immune Complex-Mediated Pathological Mechanism

A

Immune complexes of circulating antigens and IgM or IgG antibodies

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

Type III: Immune Complex-Mediated includes activation of?

A

complement, leukocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Type III: Immune Complex-Mediated includes release of

A

oxygen, nitrogen radicals, proteases, and cytokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Examples of Type III: Immune Complex-Mediated include
Arthus reactions, serum sickness, certain autoimmune diseases
26
Type IV: T-cell mediated Pathological Mechanism
CD4+ T cells (delayed hypersensitivity), CD8+ CTLs (T cell mediated cytolysis)
27
Type IV: T-cell mediated includes activation of
macrophages
28
Type IV: T-cell mediated causes release of
cytokines, oxygen and nitrogen radicals, and proteases
29
Type IV: T-cell mediated causes
direct target cell lysis and scarring fibrotic response
30
Principle of IgE
protective role in host defense and immunity to PARASITIC infections
31
Adverse role of IgE
allergies, asthma, and anaphylaxis
32
Atopic serum
serum from a sensitized atopic patient that contains antibodies to an allergen
33
Steps of Type 1 (immediate) Hypersensitivity Response
Primary exposure, induction if IgE, IgE binding to receptor on mast cells and basophil, Secondary exposure, binding of allergen to cell-associated IgE and cross linking of 2 IgE Fc, signal transduction, Mediator effects
34
Primary response: Sensitization Predisposing Factors
propensity of allergen to induce IgE (nature of allergen, food, environment), Route of exposure (respiratory, GI, skin), genetics (HLA alleles, IL-13, IL-14, CD14, cytokine), age (very young and old)
35
Type 1 (immediate) Hypersensitivity activates IgE production by
activating B cells with T cell help
36
Antibody production is
Th2 dependent - IL-4 and IL-5 enhance B cell cell IgE response
37
IN the absence of IL-4 what other cytokine can activate the receptor to initiate an allergic response
IL-13
38
_______ is involved in negative control of IgE production and immediate hypersensitivity response.
IFN-gamma
39
What route of exposure is most likely to trigger IgE production? Why?
Repiratory, GI, Skin because mast cells and IgE-bearing B cells end to line the skin, mucous membranes, and connective tissue
40
What immune response and cytokine production is required for antibody production?
Th2 and IL-4
41
What antibody may play a protective role in preventing allergens from contacting mast cells and IgE-bearing B cells?
IgA
42
What polymorphisms have been linked to hypersensitivities?
HLA alleles, IL-13 and IL-4 receptor and CD14
43
Why are very young and some elderly patients more susceptible to hypersensitivities?
decreased thymus activity
44
Induction of IgE producing-B cells is Th___ dependent
Th2
45
What cytokine/s are involved in enhancing IgE response?
IL-4 and IL-5
46
Which cytokine can mediate an allergic response in the absence of IL-4?
IL-13 (shares a receptor with IL-4)
47
Which vaccine may down regulate hypersensitivity responses in humans? How?
BCG vaccine; shifts the immune response profile to a Th1 response
48
Some believe that allergies and asthma are a deficiency in ____?
IFN-gamma
49
Explain what atopy means.
a person who develops clinical symptoms after repeated exposure (10% of the population)
50
High serum levels of IgE suggest
increased chance of hypersensitivity
51
Allergic asthma is mediated by
gamma/delta-TCR recognition of antigens processed by CD1 molecules
52
IgE binds with high affinity to
Fc receptors on mast cells or basophils
53
Which Ig-Fc receptor interaction has the highest binding affinity?
IgE-Fc on mast cells and basophils, the Fc(epsilon)RI
54
Fc(epsilon)RI is found on
mast cells and basophils
55
Fc(epsilon)RII is found on? and binds ___ with ________ affinity?
platelets, lymphocytes, monocytes, and eosinophils; IgE with low affinity
56
What cells is the main effector of Type I hypersensitivity responses?
mast cells
57
Mast cells are located in the tissue near
blood vessels in skin, CT, and lining of the gut and lungs
58
Mast cell morphology
mononuclear, granulated, basic cells in tissue
59
Basophil morphology
polynuclear, granulated, basic cells in circulation
60
What happens to the half life of IgE when bound to Fc(epsilon)RI?
it goes from being very short (2 d) to greatly extended
61
Activation - subsequent exposure - reaction happens faster because
memory T and B cells exist
62
Activation - subsequent exposure - Mechanism
allergen binds at least 2 IgE molecules on mast cells, cross-linking the IgE and causing aggregation of the Fc receptors
63
Receptor aggregation causes
activation signal to cell
64
Signal transduction involves
changes in membrane fluidity, actin filament formation, release of pre-formed granules, methylation of membrane phospholipids and influx of Ca, increased cAMP and cGMP
65
Activation causes changes in membrane fluidity resulting in
destabilization of membrane
66
Activation causes increased cGMP and cAMP intracellularly resulting in
activation of the cell to form other components de novo and slows degranulation
67
Pre-formed mediators released by the Mast cells include
histamine, eosinophil and neutrophil chemotactic factor of anaphylaxis, neutral proteases, hydrolyses, heparin
68
the role of mast cell released histamine:
Smooth muscle constriction of the bronchus and GI, and smooth muscle relaxation in the vasculature, increased vascular permeability and edema, pruritus, increased exocrine secretions
69
the role of mast cell released eosinophil chemotactic factor and neutrophil chemotactic factor of anaphylaxis:
recruitment and chemotaxis of eosinophils and neutrophils (late phase cellular reactants)
70
the role of mast cell released neutral proteases and hydrolases include:
extracellular matrix alteration via degradation (unknown reason)
71
the role of mast cell released heparin
inhibit coagulation
72
Newly synthesized mediators of activated mast cells include:
arachidonic acid and its by-products, Leukotrienes C, D, and B, prostaglandins, and thromboxanes, Platelet activating factor, cytokines IL-4, IL-13, TNF-alpha, IL-3 and IL-5
73
Arachidonic acid is released from __________ by __________
cell membrane lipids by phospholipases
74
the oxidation of arachidonic acid by _____________ results in the formation of _________________
Lipoxygenases, leukotrienes C and D and leukotriene B
75
Slow-reacting substances of anaphylaxis (SRS-A) include
leukotrienes C and D and leukotriene B
76
the role of leukotrienes C and D
cause smooth muscle contraction, increased vascular permeability, and mucus secretion
77
the role of leukotriene B
chemotactic factor for neutrophils
78
the oxidation of arachidonic acid by _____________ results in the formation of _________________
cyclooxygenases, prostaglandins and thromboxanes
79
the role of prostaglandins and thromboxanes
vascular and smooth muscle tone, platelet aggregation and immune reactivity
80
newly synthesized mediators of mast cells include platelet activating factor, which results in
platelet aggregation and secretion, neutrophil aggregation and degranulation, chemotaxis and release of oxygen radicals
81
newly synthesized mediators of mast cells include which cytokines?
IL-4, IL-13, TNF-alpha, IL-3, IL-5
82
The role of IL-4 and IL-13
further stimulation of Th2 cells and induces B cells to make IgE
83
The role TNF-alpha
activates endothelium for the extravasation of leukocytes and promotes inflammatory response
84
The role of IL-3 and IL-5
stimulate eosinophil growth and differentiation
85
Manifestations of a mild Type I Hypersensitivity
Cutaneous - "wheal and flare" and urticarial rash, Respiratory - nasal congestion, pruritus, rhinitis, conjunctivitis, sneezing and coughing Ingested - vomiting, diarrhea
86
Describe the wheal and flare reaction
wheal: edema as a result of an increase in blood vessel permeability (formed elevation) flare: blood vessel dilation (redness)
87
Manifestations of a severe Type I Hypersensitivity
laryngeal edema, hypotension and shock, bronchospasm, cardiac arrhythmia, cardiorespiratory arrest
88
Manifestations of asthmatic Type I Hypersensitivity
chronic obstructive disease of the lower airway (intrinsic or allergic)
89
Asthma is mediated by 3 events:
reversible obstruction (mucus), bronchial hyperresponsiveness to stimuli, inflammation
90
The initial Type I Hypersensitivity response occurs in
minutes
91
The late phase Type I Hypersensitivity response occurs in
hours
92
Type I Hypersensitivity response may be lethal by means of
asphyxiation from laryngeal edema, suffocation from bronchiolar constriction, shock, loss of adequate BP from overwhelming peripheral edema
93
Managing an atopic reaction involves 3 steps
identification of an allergen, avoidance of allergen, pharmacological intervention
94
How would one identify an allergen?
Challenge Test (Skin test): degree of wheal and flare is graded 1-4 correlating to degree of sensitivity or In vitro tests RIST and RAST
95
RIST
measures total IgE - radioimmuo sorbent test
96
RAST
Specific IgE - radioallergosorbent test
97
If patient is atopic but yields low titers of IgE (total or specific) this may be due to
IgE sequestration by high affinity mast cell receptors, leaving no free IgE for detection
98
If a patient is not atopic but yield high titers of IgE this may be due to
IgE not being sequestered on mast cells or during parasitic infections
99
How would one account for IgE bound to mast cells and unbound IgE?
semi-quantitative assessment comparing lowest possible reaction and highest possible reaction
100
Antihistamine effects
compete with histamine for receptor sites, preventing immediate symptoms (must be used as a PREVENTATIVE)
101
Cromolyn Sodium effects
stabilizes the mast cell membrane preventing degranulation when administered PRIOR to exposure
102
Corticosteroid effects
preventing the arachidonic acid pathway, preventing LATE phase reactants
103
Epinephrine effects
treats life-threatening symptoms by reversing the effects of histamine on smooth muscle in the GI and respiratory tracts and relaxation of vasculature (β2-adrenergic receptor agonist )
104
Xolair (Omalizumab)
humanized anti-IgE antibody, prevents the binding of IgE on mast cells Fc(epsilon)RI
105
Singulair
leukotriene receptor antagonist, blocks the effects of leukotriene D4 on the CysLT1 receptor
106
Hyposensitization Therapy
injection of diluted allergen, while slowly increasing concentration over time (weeks to months)
107
Hyposensitization Therapy Theory
IgG is produced which binds the allergen preventing it form binding to IgE-bearing Mast cell
108
Desensitization Therapy
administering very minute amounts of the allergen and increasing to larger effective doses over hours
109
Desensitization Therapy Theory
smaller doses slowly trigger sublethal doses of histamine from mast cells, depleting them of their granules so a larger dose can be administered without lethal effects
110
When would one use desensitization therapy?
horse serum anti venom for snakebite, antibiotic to which they are sensitized to is needed

Immuno Exam 3 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions