12-Over-reactions of the Immune System

Question 1

Which Ab does the Ag bind to in Type 1 Hypersensitivity reactions (T1-HSR)?

Answer 1

IgE

Question 2

Which lymphocyte is the IgE on in T1-HSR’s?

Answer 2

Mast cells

Question 3

When the Ag binds to the IgE on mast cells, what happens?

Answer 3

The mast cell degranulates.

Question 4

What binds to the surface of the cells in the T2-HSR’s?

Answer 4

Small molecules that change their structure

Question 5

What binds to the small molecules in T2HSR’s?

Answer 5

Ab’s (typically IgG)

Question 6

What are the things that float around in the blood in T3-HSR’s?

Answer 6

Small immune complexes of Ag-Ab’s.

Question 7

What do the immune complexes do in T3HSR’s?

Answer 7

they activate the complement and damages various tissues.

Question 8

What are produced in T4-HSR’s?

Answer 8

Ag-specific effector T cells

Question 9

What do the specific effector T cells do in T4-HSR’s?

Answer 9

They bind to foreign epitopes and results in a delayed hypersensitivity reaction

Question 10

What are the main mediators that cause the clinical Sx in T1-HSR’s?

Answer 10

Mast cell granule products- histamine, heparin, ECA, prostaglandins

Question 11

Which mediator in T1-HSR’s is the most important for the Sx experienced by the reaction?

Answer 11

Histamine- it causes the inflammatory effect.

Question 12

Give the mechanism and type of HSR that occurs with Goodpastures syndrome.

Answer 12

T2HSR. R-mediated inflammation of kidney –> nephritis

Question 13

Give the mechanism and type of HSR that occurs with myasthenia gravis

Answer 13

T2HSR. Ab inhibits NmAchR –> muscle weakness.

Question 14

Give the mechanism and type of HSR that occurs with Graves disease

Answer 14

T2HSR. Ab stimulates TSH receptors –> hyperthyroidism

Question 15

Give the mechanism and type of HSR that occurs with autoimmune hymolytic anemia

Answer 15

T2HSR. Opsonization and phagocytosis of RBC’s –> anemia.

Question 16

Give the mechanism and type of HSR that occurs with Blood typing

Answer 16

T2HSR. u wana get tha right type o’ blood ya heear

Question 17

Give the mechanism and type of HSR that occurs with autoimmune thrombocytopenia purpura

Answer 17

T2HSR. Opsonization and phagocytosis of platelets –> decrease platelets –> bleeding

Question 18

Give the mechanism and type of HSR that occurs with systemic lupus erythematosus

Answer 18

T3HSR. Complexes deposit on cells –> kill DNA and other nucleoproteins –> nephritis, arthritis, and vasculitis

Question 19

Give the mechanism and type of HSR that occurs with rheumatoid arthritis

Answer 19

T3HSR. Ab complexes settle in the joints –> inflammation of synovium and erosion of cartilage and bone

Question 20

What is the rheumatoid factor?

Answer 20

It’s an autoantibody that reacts against the Fc portion of IgG, which complex and travel to the joints to

Question 21

Give the mechanism and type of HSR that occurs with type 1 diabetes

Answer 21

T4HSR. CD8 T cells react against islet cells or insulin –> diabeeeetus

Question 22

Give the mechanism and type of HSR that occurs with multiple sclerosis

Answer 22

T4HSR. T cell attack of myelin –> demyelination –> weakness and blurred vision.

Question 23

Give the mechanism and type of HSR that occurs with Hashimoto’s thyroiditis

Answer 23

T cell attack of thyroid –> hypothyroidism

Question 24

What is immunologic tolerance?

Answer 24

It’s when the immune system doesnt attack a non-self Ag

Question 25

Why would tolerance induction be good for treatments?

Answer 25

It would be good for treatments for transplanted organs, allergy sufferers, etc.