Fetal Transplant

Question 1

Self-to-self transplant

Answer 1

Autograft

Question 2

Identical twin-to-twin transplant

Answer 2

Isograft

Question 3

Person-to-person transplant

Answer 3

Allograft

Question 4

Species-to-species (strong rejection)

Answer 4

Xenograft

Question 5

Primary cells in transplant rejection

Answer 5

Th1, Th17, CD8, NK, INF-gamma, macrophages, IL-2 and 21, IL-4

Question 6

Intimal thickening leading to graft ischemia

Answer 6

Chronic rejection

Question 7

Overall way to induce tolerance

Answer 7

Manipulate Tregs

Question 8

Specific ways to induce tolerance

Answer 8

Provide inhibitory second signals (CTLA-4), T regulatory cells (CD4, 25) or cytokines (Il-21, IL-23, IL-10 & TGF-beta) to override Th1, Th17 and CD8 responses

Question 9

How do Tregs suppress rejection?

Answer 9

Tregs suppress/kill recipient T cells that don’t recognize graft/try to attack it

Question 10

Recipient T cells attack transplant

Answer 10

Organ transplant

Question 11

T cells in transplant attack recipient’s tissues

Answer 11

Bone marrow transplant

Question 12

GVHD

Answer 12

Graft vs. host disease

can occur in immunoincompetent patients receiving transfusions (rxn w/ lymphocytes)

Question 13

Reason why xenografts are ineffective

Answer 13

α-1,3 GT
- Primates deleted this gene a long time ago, and developed an anti-α-1,3 GT in response to gut bacteria
- Lots of other animals still make α-1,3 GT
Also, xenovirus transmission is an issue

Question 14

Complex presented by trophoblastic (fetal) tissue at maternal-fetal interface

Answer 14

“public”
MHC HLA-G

*NO DISPLAY OF MHC I OR II

Question 15

Characteristics of pregnant uterine NK cells

Answer 15

Inhibited by MHC HLA-G
No FcR displayed
Produce angiogenic factors to support placenta

Question 16

Role of maternal γδ T cells

Answer 16

Hone to uterus, promote tolerance to fetus

Question 17

maternal T lymphocytes (ly) come in contact with fetal ly (maternal & paternal MHC) at the placental interface maternal ly or in the fetus itself, ____________

Answer 17

They are converted by fetal TGF-beta to paternal specific T-regs

Question 18

______ promotes display of DAF on uterine cells

*Decay accelerating factor is a regulator of complement system

Answer 18

Progesterone

Question 19

Spontaneous abortion may result from this

Answer 19

Failure of maternal ly conversion to paternal specific T regs at the placental interface

Question 20

This T-cell group promotes success of pregnancy, but may increase risk of intracellular infections

Answer 20

Th2

- also Tregs

Question 21

T-cell group associated with decreased success in pregnancy

Answer 21

Th1 bias