Lecture12

Question 1

What is hypersensitivity?

Answer 1

Immune reactions that can cause tissue damage. All require previous exposure to the antigen/allergen

Question 2

What is a type 1 reaction?

Answer 2

Can have localized or systemic reactions. IgE finds a mast cell and attaches, when exposed again, this will happen again, cross clamp and this causes allergic reactions

Question 3

What is released from mast cells and basophils in an allergic reaction? What does it cause?

Answer 3

Histamine, cytokines and other lipid molecules are released, and together they dilate blood vessels, contract smooth muscle

Question 4

Name two treatments of anaphylaxis:

Answer 4

Antihistamines, block the action of histamine, or, Epinephrine, it constricts blood vessels, dilates air passages in lungs and raises blood pressure

Question 5

What is a type II reaction?

Answer 5

Cytotoxic, due to a blood transfusion with wrong type of blood. This leads to hemolysis of RBCs

Question 6

What is a type III reaction?

Answer 6

Immune complex binds to endothelium, then activates complement which generates chemoattractants for neutrophils, - these arrive, then release their granules and enzymes to damage tissue

Question 7

What is a type IV reaction?

Answer 7

This is normal activation of the adaptive immune system, they have memory cells from previous exposure. Lytic enzymes from activated macrophages leak and cause local tissue destruction

Question 8

What is the treatment for type IV reactions?

Answer 8

Corticosteroids for contact dermatitis, and immunosuppressives (cortisone) for transplant rejection

Question 9

What is thimerosal?

Answer 9

Is it ethyl mercury, it is used as preservative for multi dosage vaccine vials. Used in Hepatitis virus vaccines and Influenza

Question 10

What is naturally acquired active immunity?

Answer 10

individual is exposed to antigens in course of daily life can produce immunity.
Ex: unionized child gets chickenpox and develops immunity after infection

Question 11

What is naturally acquired passive immunity?

Answer 11

The natural transfer of antibodies

ex: Maternal transfer of IgG antibodies over placenta, or the IgA antibodies in mothers breast milk

Question 12

What is artificially acquired active immunity?

Answer 12

Result of vaccination, where specially prepared antibodies are introduced into the body

Question 13

What is artificially acquired passive immunity?

Answer 13

involves the introduction of antibodies from an animal or person who is already immune to the disease