EXAM 13: immune reaction to blood

Question 1

Rh factor is present in what percent of the human population

Answer 1

85%

Question 2

what is an Rh factor?

Answer 2

• a very powerful antigen capable of stimulating an intense antibody response in humans
• have no naturally occurring isoantibodies (so any present antibodies are there due to exposure to Rh+ blood)

Question 3

what happens if someone who is Rh- gets blood that is Rh+?

Answer 3

1. there is an antibody response
2. if they are exposed for a second time the response will be even more intense

Question 4

what happens if someone who is Rh+ gets blood that is Rh+?

Answer 4

nothing

Question 5

what happens if someone who is Rh+ gets blood that is Rh-?

Answer 5

nothing

Question 6

erythroblastosis

Answer 6

Rh reaction is seen in newborns due to the antibodies of the mother passing into fetal circulation and the antibodies attack the newborn’s RBCs
cannot prevent this

Question 7

isoerythrolysis

Answer 7

• in horses
• horses don’t have Rh factors
• antibodies transfer in the colostrum
• can be avoided by withholding colostrum from the foal

Question 8

are antigens different between species?

Answer 8

yes

Question 9

Isoantibodies are _______ common and ______ reactive in animals than in human blood

Answer 9

less
less

means that an animal might not have an allergic reaction the first time it gets incompatible blood

Question 10

what are the most important canine antigens (3)

Answer 10

DEA 1.1
DEA 2.2
DEA 7

Question 11

a safe universal canine donor is one that is _______________________________

Answer 11

DEA-1.1, DEA-2.2, and DEA-7 negative

Question 12

why do donor organs get rejected?

Answer 12

the recipient body recognizes the tissue as being foreign and initiates an immune response to remove it (T lymphocytes recognize foreign antigens, attack the tissue, and ultimately reject the transplant or graft)

Question 13

are all tissue antigens the same between identical twins?

Answer 13

yes
they can transplant things between them without issue

Question 14

what are the 4 types of skin grafts?

Answer 14

autograft
isograft
homograft (allograft)
heterograft (xenograft)

Question 15

autograft

Answer 15

• tissue (skin) taken from one site moved to another part of the same individual.
• readily accepted
• no foreign antigens are introduced into the body

Question 16

isograft

Answer 16

• tissue is transplanted between identical twins (genetically identical individuals)
• readily accepted (b/c they have the same antigens)

Question 16

homograft (allograft)

Answer 16

• tissue is transplanted between 2 different individuals of the same species
• after transplantation, it vascularizes, looks healthy, then undergoes necrosis and is REJECTED
• rejected because it has foreign antibodies and is attacked by the immune system

Question 16

Heterograft (xenograft)

Answer 16

• transplantation between different species
• quickly incites immune response and is rejected due to foreign antigens

Question 17

what has opened the door to tissue transplants?

Answer 17

New drugs (cyclosprine) that supress the immune system
- impair T lymphocyte function
- must be taken on a continuous basis