Brainscape's Knowledge GenomeTM

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


See full index

BIO 4650 Final > Allergy and Hypersensitivity > Flashcards

Allergy and Hypersensitivity Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What is hypersensitivity?

A

an inappropriate immune response to antigens that pose little to no threat

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

Type 1 Hypersensitivity immune mediator

A

IgE

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

Type 1 is initiated by?

A

an interaction between an IgE Ab and a multivalent antigen

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

Common allergic reaction

A

hay fever, asthma, eczema, bee stings, hives, food allergies

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

What type of individuals are genetically more susceptible to allergens?

A

Atopic

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

Atopic individuals

A
  • Healthy individuals only produce IgE in regards to parasitic infections
  • Atopic individuals produce IgE against common environmental antigens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Allergens

A
  • are non-parasitic antigens
  • soluble proteins or glycoproteins
  • Many antigenic sites per molecule
  • Often have intrinsic enzymatic properties
  • Contain potential PAMPs, stimulating innate immunity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Type 1 reaction

A
  • IgE antibodies act by cross-linking Fce receptors on the surfaces of innate immune cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

IgE cross-linking to FceR1

A
  • causes degranulation

- granule contents released

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

Granule contents released

A 
histamine
heparin
proteases
leukotrienes
prostaglandins
chemokines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Mediators

A

act on surrounding tissues and cells to cause symptoms

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

FceR1

A
  • high-affinity iGe receptor
  • found on mast cells, eosinophils, and basophils
  • linking receptors trigger Lyn-mediated phosphorylation of ITAMS
  • triggers signaling pathway, leading to allergic effects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Activate mast cells leads to

A
  • tissue changes remodeling
  • Acute changes in function
  • Inflammation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Type of mediators

A
  • Histamines
  • Leukotrienes and Prostaglandins
  • Cytokines and Chemokine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Histamines

A

are formed by decarboxylation of histidine amino acid and is a major component of mast cell granules

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

What happens when binds to histamine receptors

A
  • contraction of intestinal and bronchial smooth muscles, increased permeability of venues, and mucous secretion
  • increase vasopermeability and vasodilation, and increase stomach acid
  • mediates mast cell chemotaxis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Leukotrienes and Prostaglandins

A
  • second messengers and are formed when membrane phospholipids are enzymatically cleaved
  • active at nanomole levels
  • more potent stimulators of vascular permeability and mucous secretion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Major cause of asthma symptoms

A

Leukotrienes and prostaglandins

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

IL-4 and IL-13

A

stimulates Th2 responses to increase IgE production by b cells

20
Q

IL-5

A

recruits and activates eosinophils

21
Q

TNF-alpha

A

Contribute to shock in systemic anaphylaxis

22
Q

CXCL-8

A

acts as a chemotactic factor, attracting other cells

23
Q

GM-CSF

A

Stimulates production and activation of myeloid cells (granulocytes)

24
Q

Type 1 Early response

A
  • occur within minutes of allergen response

- Mediated by mast cell granule release of histamine, leukotrienes, and prostoglandins

25
Q

Type 1 late response

A
  • Hours later
  • A result of recruited cells
  • Cytokines release from mast cells increase expression of chemokines and CAMs on endothelium facilitating influx of neutrophils, eosinophils, and Th2 cells
  • Eosinophils play a large role in late-phase recruiting neutrophils and degranulation
26
Q

Type 1 hypersensitivity Reaction categories

A
  1. Systemic anaphylaxis
  2. Localized hypersensitivity
  3. Food allergies
27
Q

Systemic anaphylaxis

A
  • initiated by an injected or gut-absorbed allergen
  • Symptoms: labored respiration, drop in blood pressure leading to anaphylactic shock, contraction of smooth muscles leading to bronchiolar constriction
  • Treatment: Epinephrine ( steroid) target inflammatory (TNF-a)
28
Q

Localized hypersensitivity reactions

A
  • Pathology is limited to a specific tissue or organ
  • Includes allergic rhinitis (hay fever), allergic conjunctivitis, asthma, atopic dermatitis (eczema) atopic urticaria (hives) and food allergens
  • Symptoms: result from release of mediators in immediate exposure area
29
Q

Food allergies

A
  • Food allergens are often water-soluble glycoproteins stable to heat, acid, and proteases
  • Can cause vomiting and diarrhea (constriction of muscles, mucous increase) and gut vasodilation
30
Q

Environmental and genetic basis for type 1

A
  • air pollution to diet

- genetics both influence susceptibility to allergies

31
Q

Hygiene Hypothesis

A
  • exposure to some pathogens early in life provides a better T-cell balance
  • Avoids dominance of Th2 subset, which promotes IgE production by B cells
  • developed countries have an increase in allergies
32
Q

Type 1 diagnosis

A
  • skin testing
  • swelling and redness
  • quantify total or allergen-specific IgE serum levels
33
Q

Type 1 treatments

A
  • Antihistamines, leukotriene antagonist, and inhalation corticosteroids
  • Desensitization immunotherapy (repeat low-dose exposure may induce Th1 and Treg cells) (anti-IgE antibodies that bind and inhibit the allergen-specific IgE from binding to mast cell FceR molecules
34
Q

Type II Hypersensitivity

A

Antibody-mediated cell cytoxicity

  • Complement activation or NK activated through ADCC
  • Transfusion reactions
  • IgG or IgM
35
Q

Transfusion

A
  • Adults possess antibodies to the blood type they do not have
  • Antibodies will quickly attach to the donor blood cells and trigger complement
  • The degraded RBC components can build up to toxic levels
36
Q

Hemolytic Disease of the new born

A
  • Develops when maternal IgG Ab specific to the expressed Rh allele crosses the placentia
  • First pregnancy mother is Rh(-) and her fetus is Rh(+) she will be exposed to the antigen. Anti-Rh IgG and memory cells
  • Second pregnancy her Fetus is (+), her memory cells will recognize the antigen and produce Anti-Rh and will cause the fetus blood to lyse
  • Rho gam shot
  • UV light
37
Q

Type III hypersensitivity

A
  • Immune complexes
  • May deposit in tissues if they aren’t cleared correctly
  • Release of inflammatory mediators and vasoactive mediators
38
Q

Type III symptoms

A
  • Vasculitis if in blood vessel
  • Glomerulonephritis if in kidney
  • Arthritis if in joints
39
Q

Immune complex-mediated hypersensitivity

A

can resolve spontaneously

- eventually complexes are cleared so long as Ag eventually goes away

40
Q

Autoantigens can be involved in immune complex-mediated reactions

A

Ag can’t completely go away in such a case

41
Q

Type IV Hypersensitivity

A
  • Delayed Type (DTH)
  • Purely cell mediated
  • Initiated by T cells
42
Q

Type IV is characterized by

A

recruitment of macrophages at inflammation site

43
Q

Example of Type IV

A

poison ivy

44
Q

Sensitization Phase

A
  • Initiation involves sensitization by an antigen
  • Initial exposure triggers production of a T-cell response
  • CD4+ Th1 subset
  • 1-2 weeks
45
Q

Effector Phase

A
  • induced by secondary exposure to a sensitizing ag

- induces production of Th1 inflammatory cytokines

BIO 4650 Final (3 decks)

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