Type III & IV Hypersensitivity (30)

Question 1

Type III hypersensitivity is also called ______

Answer 1

antibody complex-mediated

Question 2

How does type III hypersensitivity develop?

Answer 2

when antigens and antibodies combine to form immune complexes which if deposited in large amounts of tissues, trigger severe inflammation with damage caused mostly by neutrophils

Question 3

What do you need in order for type III hypersensitivity to occur?

Answer 3

pre-exposure with development of antibodies

Question 4

The prerequisite for the development of immune complex is the persistent _____

Answer 4

presence of soluble antigen and antibody

Question 5

What do a soluble and antigen and antibody form?

Answer 5

insoluble immune complexes that become trapped on the basement membrane of small blood vessels

Question 6

What are the most frequently affected sites of type III hypersensitivity?

Answer 6

skin, lungs, kidneys, joints, brain (where large capillaries exist to filter blood)
6-8 hrs after exposure

Question 7

What are the cells and mediators for type III hypersensitivity?

Answer 7

neutrophils - granule contents
macrophages
mast cells
complement

Question 8

What is the role of anaphylotoxins? Give examples

Answer 8

microbial killing
C3a
C5a

Question 9

Trace the type III hypersensitivity pathway

Answer 9

Question 10

C3a and C5a are also called ____ since, when injected in sufficient amounts, can kill an animal in a manner similar to anaphylaxis by causing _______ = pro-inflammatory

Answer 10

anaphylotoxins
causing mast cells to release histamine granules

Question 11

What are the two major forms of type III hypersensitivity?

Answer 11

localized
generalized

Question 12

What is localized type III hypersensitivity?

Answer 12

immune complexes are deposited in tissues and the reaction is seen at the site of antigen entry

the antigen is introduced into the tissue and preformed antibody in circulation binds to the antigen

immune complexes stay localized

Question 13

What is generalized (systemic) type III hypersensitivity?

Answer 13

excess antigen in circulation

antibody in circulation (IgG) binds to circulating antigen and forms free-floating immune complexes in blood

immune complexes circulate and get deposited in blood filtration points

Question 14

What is an arthrus reaction?

Answer 14

antigen injected SQ

acute inflammation develop in injection site in the skin within 1-2 hours

Question 15

What is different with mast cells in type III hypersensitivity?

Answer 15

activation of them is different

instead of IgE, receptors are stimulated by complement intermediates (C5a, C3a) or IgG

not fully activated - only some granules are released

Question 16

What is blue eye?

Answer 16

type III hypersensitivity

natural infection with adenovirus 1

immune complex formation resulting from release of virus especially from infected corneal endothelial cells brings about corneal damage

Question 17

In type III hypersensitivity, degranulation leads to death of _____ and _____

Answer 17

neutrophils
mast cells

Question 18

What is hypersensitivity pneumonitis?

Answer 18

cattle and horses housed during winter are exposed to dusty feeds and moldy hay — serves as an antigen

when inhaled, spore antigens encounter antibodies within the alveolar walls —> it results in immune complexes and complement activation lead to pneumonia

Question 19

In generalized type III hypersensitivity, ____ is injected and is in circulation

Answer 19

antigen

immune complexes form in the blood stream

Question 20

What are factors that influence deposition of immune complexes?

Answer 20

size and amount
ability of host to cleave the immune complexes
anatomic and hemodynamic factors

Question 21

What is acute serum sickness?

Answer 21

generalized type III hypersensitivity

large amount of passively administered serum form as different species such as antitoxin or gamma globulin

Question 22

Chronic drug exposure is [localized/generalized] type III hypersensitivity

Answer 22

generalized

(methamiazole)

Question 23

Infectious agents are? What type of type III hypersensitivity?

Answer 23

large number of persistent circulating antigen

generalized

Question 24

What is glomerulonephritis

Answer 24

when immune complexes deposit in the glomeruli, they cause basement membrane thickening and stimulate glomerular cells to proliferate

lesion called membrano-proliferative glomerulonephritis

Question 25

What is purpura hemorrhagica in equines?

Answer 25

related to prior bouts of strangles and vaccine

upper respiratory infeciton

Question 26

T/F: Autoimmune diseases can also be a type III hypersensitivity

Answer 26

TRUE

Question 27

Type IV Hypersensitivity is also called _____

Answer 27

delayed type
T cell-mediated immunity

Question 28

What are the mechanisms of tissue injury and disease for type Iv hypersensitivity?

Answer 28

macrophage activation and cytokine-mediated inflammation

direct target cell lysis, cytokine-mediated inflammation

Question 29

T/F: Types I-II are antibody-mediated, and Types III-IV are T-cell mediated

Answer 29

FALSE - only Type IV is T-cell mediated

Question 30

Are antibodies important in type IV hypersensitivity?

Answer 30

NO

Question 31

The mechanism for type IV hypersensitivity is established by the elimination of ______

Answer 31

intracellular pathogens

Question 32

Delayed hypersensitivity reactions result from the interactions among the _____

Answer 32

antigen
APCs
Tcells
macrophages

Question 33

In Type IV hypersensitivity, cytokine-mediated inflammation uses a [cell-associated/soluble] antigen, and T-cell mediated killing of host cells uses a [cell-associated/soluble] antigen

Answer 33

cytokine: soluble antigen
T cell-mediated: cell-associated

Question 34

Type IV hypersensitivity makes a _____, hard, raised lesions

Answer 34

induration

Question 35

Bovine tuberculosis is a product of which hypersensitivity type?

Answer 35

IV

is zoonotic

Question 36

Just do Faulkner’s worksheet on canvas. Dont feel like making flashcards for this