Immune Dysfunction Flashcards
What aspect of our immune system is rapid, non-specific, and does not provide long-lasting protection?
Innate Immunity
has no memory, but the response is always identical
S3
What are the 4 cellular components of the innate immunity system?
- Neutrophils
- Macrophages
- Monocytes
- NK cells (Natural Killer Cells)
S4
What cell (of the innate immunity response) responds the fastest to infection?
Neutrophils
S4
What cell (of the innate immunity response) provides a slower but more prolonged response to infection?
Macrophages
S4
What are the characteristics and actions of neutrophils?
- Migrate rapidly to bacterial infections
- Release cytokines to phagocytize
- ½ life is 6 hours
- Sensitive to acidic infection environments
- Become purulent exudate
S6
What type of immune cell is the largest blood cell and what is their role?
- Monocytes (largest blood cell)
- Circulates to specific tissue areas to differentiate into macrophages
not mentioned in lecture - but the chart also shows them turning into dendritic cells - and we know how tricky they like to be
S7
What are the pertinent characteristics of monocytes/macrophages?
- Mobilize just after neutrophils
- Phagocytic destruction via NO & cytokines
- Persist at site in chronic infections (fight infection long term)
S7
What cells play a major role in allergies, asthma, and eczema?
Basophils and Mast cells
S8
What characteristics does Adaptive Immunity possess?
- Present only in Vertebrates
- Delayed onset of action
- Capable of memory and specific antigen response
Vaccinations are also a form of adaptive memory
S10
What are the cellular components of the adaptive immunity system?
Helper T-cells
Cytotoxic T-cells
S11
Where do T-cells originate? Where do they mature?
T-cells originate in the bone marrow and mature in the Thymus.
S11
What is hypersensitivity?
Foreign antigen reaction which causes altered T-cell and antibody response
Response varies from uncomfortable rash to fatal anaphylaxis
S14
What occurs during a Type I Allergic Response?
- 1st exposure: T-Cells stimulate B cells to produce IgE immediately
- 2ⁿᵈ exposure: Antigen releases Ca⁺⁺ → histamine, inflammatory mediators, heparin are released.
(Histamine triggers: bronchostriction, Vascular permeability, vasodilation, gastric acid)
S15
What are common drugs used to prevent the histamine effects of Type I allergic responses?
- Antihistamines
- Cromolyn Na⁺
- Bronchodilators
- COX Inhibitors
- Diagnostic allergen tests
- small doses of allergen to desensitize
S16
What is another name for Type II Allergic Responses?
What mediates these types of responses?
What is the reaction severity and time?
- Cytotoxic Hypersensitivity
- Mediated by IgG, IgM, and Complement system → activate B-cells → produce antibodies.
- Severity will vary - reaction time in minutes or hours
mediated by GMC
S17
What are examples of Type II Allergic Responses?
- Hemolytic Anemia
- Myasthenia Gravis
- Transfusion Reactions
S17
What is the treatment for Type II Allergic Responses?
- Anti-inflammatories
- Immunosuppressants
- IVIG up and coming
S17
What is another name for Type III Allergic Response?
Immune Complex Hypersensitivity
S18
What occurs with Type III Allergic Response?
Failure of immune system to eliminate antibody-antigen complex.
- Build up in the joints, kidneys, skin and eyes
S18
What are examples of Type III Allergic Responses?
Systemic Lupus Erythematosus and Rheumatoid arthritis
S18
Treatment for type III allergic response?
- Anti-inflammatories
- might need immunisuppressives
S18
What is a Type IV Allergic Response?
T-lymphocyte and monocyte/macrophage mediated response that does not involve antibodies.
S19
What are examples of Type IV Allergic Responses?
- Contact Dermatitis
- Tuberculosis
- Stevens-Johnson Syndrome
S19
Treatment for type IV allergic reaction?
- anti-inflammatories
- immunosuppressives
S19
What is Biphasic anaphylaxis?
- Occurs following an asymptomatic period without second exposure
- Secondary anaphylactic episode occurring 8 - 72 hours later.
occurs is 4-5% of the pts that experience anaphylaxis
S23
What are risk factors for a secondary anaphylactic episode?
- Severe initial response
- Initial response required multiple epi doses
S23
What is the epinephrine dose for adult anaphylaxis?
10 mcg - 1000mcg IVP q 1-2 min
S26
What is the crystalloid dosage for anaphylaxis?
NS: 10 - 25 mL/kg over 20 min
repeat PRN
S26
What is the colloid dosage for anaphylaxis?
10 mL/kg over 20 min
repeat PRN
S26
Why is epinephrine the drug of choice for anaphylaxis?
- ↓ degranulation of mast cells & basophils → reduced vasodilation
- α1 = Increased blood pressure
- β1 = positive Inotropy & chronotropy
- β2 = Bronchodilation
S27
What drug classes are secondary treatments for anaphylaxis?
- Bronchodilators
- Antihistamines
- Corticosteroids
S28
