transplant immunology

Question 1

Graft transplanted from one individual to the same individual

Answer 1

autologous graft

Question 2

Graft transplanted between two genetically identical (or very similar) individuals

Answer 2

syngenetic graft

Question 3

Graft between two genetically different individuals

Answer 3

allogenetic graft

Question 4

transplanting a cell or tissue to the same anatomical site

Answer 4

orthotopic

Question 5

transplanting a cell or tissue to a different anatomical site

Answer 5

heterotopic

Question 6

transfer of circulating cells from one individual to another

Answer 6

transfusion

Question 7

____ immune cells react to allogeneic grafts

Answer 7

alloreactive

Question 8

rejection of a graft is due to mismatch in ____ molecule; if it does not match, T cells will recognize graft as foreign

Answer 8

MHC

Question 9

CD4+ T cells require ____ to become activated

Answer 9

antigen + MHC II

Question 10

CD8+ T cells require _____ to become activated

Answer 10

antigen + MHC I

Question 11

T cell binds to self MHC and foreign peptide with ____ affinity

Answer 11

high

Question 12

MHC II + peptide activates CD4+ T cells and T cells produce ____ to help propagate the immune response

Answer 12

cytokines

Question 13

self MHC molecule presents foreign peptide to T cell selected to recognize ____ weakly, but may recognize ____ complexes well

Answer 13

self MHC; self-MHC/ foreign peptide complexes

Question 14

two examples of direct alloantigen recognition

Answer 14

1. T cell recognizes allogeneic MHC molecule whose structure resembles self MHC+foreign peptide complex
2. T cell recognizes structure formed by both allogeneic MHC molecule and bound peptide (self peptide)

Question 15

If the allogeneic MHC+self peptide

is structurally similar to self MHC and foreign peptide, it will result in _____

Answer 15

T cell activation

Question 16

When T cells recognize allogeneic MHC (or allogeneic MHC+self peptide) directly it is called ______

Answer 16

direct alloantigen recognition

Question 17

presentation of processed peptide of allogeneic MHC molecule bound to self MHC molecule

Answer 17

indirect alloantigen recognition

Question 18

indirect alloantigen recognition is an example of ____ or ____

Answer 18

cross presentation; cross priming

Question 19

how do allogeneic T cells lead to graft rejection?

Answer 19

1. hyperacute rejection
2. acute rejection
3. chronic rejection

Question 20

hyperacute rejection is characterized by ____ and eventual ____of the graft blood vessel that begins within ____ of the transplant

Answer 20

thrombosis formation; occlusion; minutes to hours

Question 21

results of hyperacute rejection

Answer 21

complement activation, endothelial damage, inflammation and thrombosis

Question 22

in acute rejection, ____ become activated after about a week and produce cytokines

Answer 22

alloreactive T cells

Question 23

results of acute rejection

Answer 23

parenchymal cell damage
interstitial inflammation
endothelialitis

Question 24

grafts that survive for 6 months or more can eventually develop ____ due to _____

Answer 24

blood vessel thickening; intimal smooth muscle formation

Question 25

results of chronic graft rejection

Answer 25

chronic DTH reaction in vessel wall intimal smooth muscle cell proliferation vessel occlusion

Question 26

cells from the common myeloid progenitor

Answer 26

erythrocytes (RBCs), platelets, basophils, eosinophils, neutrophils, monocytes/macrophages

Question 27

cells from common lymphoid progenitor

Answer 27

B lymphocytes, T lymphocytes, NK cells

Question 28

While same immune reactions/rejection can occur with bone marrow transplant, there is also the risk of the graft attacking the host, which is called:

Answer 28

graft vs host disease

Question 29

tumor antigens are recognized by _____

Answer 29

tumor-specific CD8+ T cells

Question 30

types of tumor antigens recognized by T cells

Answer 30

1. mutated forms of normal self proteins 2. product of oncogene or mutated tumor suppressor gene 3. overexpressed or aberrantly expressed self protein 4. products of oncogenic virus

Question 31

Some cancers can down-regulate the expression of MHCI. Why is this important to the immune system?

Answer 31

NK cell becomes activated and can kill infected cell

Question 32

activated NK cells cal produce ____

Answer 32

IFN-gamma

Question 33

the production of IFN-gamma is important because?

Answer 33

IFN-gamma activates macrophages and allows them to kill phagocytosed tumor cells

Question 34

function of tumor macrophages depends upon the ____

Answer 34

cytokine microenvironment

Question 35

____ leads to M1 (or classical) macrophage activation

Answer 35

IFN-gamma

Question 36

_____ leads to M2 (or alternative) macrophage activation

Answer 36

IL-4, IL-13, IL-10

Question 37

M1 macrophages can suppress tumors/kill tumor cells through _____

Answer 37

bactericidal activity immunostimulation inflammatory cytokines

Question 38

M2 macrophages can enhance tumors through _____

Answer 38

scavenging tissue repair matrix remodeling angiogenesis

Question 39

The principal mechanism of tumor immunity is killing of tumor cells by ____

Answer 39

CD8+ cytotoxic T lymphocytes

Question 40

experimental evidence suggests that the CD8+ CTL’s are most effective against _____

Answer 40

DNA virus-induced tumors

Question 41

____ may be necessary for CTL activation

Answer 41

cross-priming

Question 42

role of CD4+ T cells in CTL differentiation

Answer 42

1. help to activate CD8+ T cells- produce cytokines that stimulate CTL differentiation 2. produce Th1 cytokines that lead to classical (M1) macrophage activation

Question 43

People with _____ are at an increased risk of developing cancer

Answer 43

chronic inflammatory diseases