Transplantation

Question 1

Autologous graft

Answer 1

graft transplanted from an individual to the same individual

Question 2

Syngeneic grafts

Answer 2

transplant between identical twins

Question 3

Allogeneic graft

Answer 3

transplant between unrelated individuals. Most common form

Question 4

Xenogeneric graft

Answer 4

transplant between two different species (often pigs to humans)

Question 5

Orthotopic transplant

Answer 5

graft placed in it’s normal anatomic location

Question 6

Heterotopic transplant

Answer 6

graft placed in an a different location than where you would normally find it

Question 7

First set rejection

Answer 7

rejected in about 7-10 days

Question 8

Second set rejection

Answer 8

reject in 2-3 days. Similar to acquired immune reponse.

Question 9

Immunologically privileged sites

Answer 9

where allogeneic transplant can be placed without risk of rejection (ex - cornea)

Question 10

How do immunologically privileged sites work?

Answer 10

extracellular fluid that bathes these tissues don’t elave through the conventional lymphatic system
TGF-beta produced here
Fas pathway

Question 11

Why are MHCs targets during graft rejection?

Answer 11

polymorphism

probability that 2 random people have the same MHCs is damn near impossible

Question 12

Hyperacute Reaction

Answer 12

happens within minutes
untreatable
common
mediated by pre-exisiting antibodies

Question 13

Acute Reaction

Answer 13

happens in about a month
treatable
basically your immunity reacting the the foreign transplant

Question 14

Acute humoral region

Answer 14

antibody and complement mediated lysis of graft tissue

causes necrosis of blood vessel walls

Question 15

acute cellular rejection

Answer 15

cell mediated lysis of graft tissue by CTLs, NK cells, and/or macrophages

Question 16

Chronic rejection

Answer 16

happens within months or years
no treatment
mechanism unknown

Question 17

Prevent rejection with immunosuppression

Answer 17

use corticosteroids, cyclosporine, and antilymphcyte globulin

Question 18

Cyclosporine

Answer 18

inhibits IL-2 and IFN gamma gene expression, prevent acitivation of cell mediated immunity.

Question 19

Corticosterois

Answer 19

lyse immature thymocytes, block release of cytokines from macrophages and inhibit leukocyte migration

Question 20

anti lymphocyte globulin

Answer 20

horse serum. kills wanting and unwanted lymphocytes, but can reverse acute graft rejection

Question 21

Depletion of what from the graft can help prevent rejection?

Answer 21

passenger leukocytes

Question 22

What makes bone marrow transplant different

Answer 22

the bone marrow can reject the patient in graft vs host disease.
you want the donor hematopoetic stem cells to repopulate the recipient bone marrow

Question 23

Acute GVHD

Answer 23

quickly following bone marrow transplant.
Involves epithelial cell necrosis of skin, liver and GI tract
can be fatal

Question 24

Chronic GVHD

Answer 24

fibrosis in organs causing dysfunction

fatal if it’s affecting critical organs

Question 25

Skin grafts

Answer 25

often used with burn victims autologous grafts most successful allogeneic grafts can be used for a short peroid w/ immunosuppresion

Question 26

kidney transplants

Answer 26

mostly from cadaveric donors, but can also do it with unrelated living donors

Question 27

liver transplant

Answer 27

has a large risk for GVDH | most donations are living related donors

Question 28

Heart transplant

Answer 28

high success rate | antibody mediated vascular injury is a risk

Question 29

pancreas transplant

Answer 29

used to treat diabetes mellitus | new approach that hasn't had that much success

Question 30

Why does mother not reject fetus?

Answer 30

- Trophoblasts don't express paternal MHC proteins, and may secrete inhibitory cytokines like TGF-beta - tryptophan is broken down at fetal-materal interface by the enzyme indolamine 2,3 dioxygenase. These t lymphocytes react poorly to antigen