Transplants and Amyloidosis

Question 1

Explain the types of transplants:

1) allograft
2) autograft
3) isograft
4) xenograft

Answer 1

1) donor and recipient genetically different but same species
2) self to self
3) donor and recipient are identical twins
4) donor and recipient are from different species

Question 2

What is the greatest barrier to a successful transplant?

Answer 2

rejection

Question 3

What are the different types of rejection?

Answer 3

cell mediated- direct and indirect

humoral

Question 4

Type of rejection due to activation of recipient CD4+ and CD8+ T cells by display of donor MHCs on recipient APCs?

Answer 4

Direct Cellular rejection

Question 5

Type of rejection due to activation of CD4+ T cells leading to B cell production of Ab by display of donor antigens on recipient APCs?

Answer 5

Indirect Cellular rejection

Question 6

What are the 3 types of antibodies that play a role in humoral rejection?

Answer 6

anti-ABO Ab
pre-formed anti-HLA Ab (from pregnancy/previous transplant/transfusion)
anti-HLA Ab formed post-transplant

Question 7

What tests must be run before a donor can be matched with a recipient?

Answer 7

ABO typing
HLA typing
alloantibody testing
lymphocyte cross-match testing

Question 8

What type of rejection is most likely to occur in a renal allograft transplant?

Answer 8

chronic

immunosuppression will prevent acute rejection

Question 9

Describe the mechanism for acute renal allograft rejection

Answer 9

host macrophages and CD8+ cells are activated causing cell mediated hypersensitivity
and
host CD4+ cells get activated, and lead to Ab production in antibody mediated hypersensitivity
last days to weeks

Question 10

What causes hyperacute renal allograft rejection?

Answer 10

anti-ABO and pre-formed anti-HLA Ab –> complement activation –> thrombi –> necrosis in minutes to hours

Question 11

What is the mechanism for graft vs. host disease?

Answer 11

transplanted donor T cells recognize host cells as foreign

Question 12

Define amyloidosis?

Answer 12

a group of disorders with deposition of amyloid protein in extra-cellular spaces in tissues/organs

Question 13

What tests would you do to confirm an amyloidosis diagnosis?

Answer 13

tissue biopsy
HE stain (linear non-branching fibrils in beta sheets) Congo red stain (red) with green bi-refringence 
immunohistochemistry or liquid chromatography and mass spectrometry to determine the specific type

Question 14

What proteins build up in primary or AL systemic amyloidosis?

Answer 14

Ig (lambda) light chains or amino-terminal fragments of light chains (Bence Jones proteins) secreted by monoclonal plasma cells

Question 15

Build up of fragments of the serum amyloid associated (SAA) protein associated with HDL in combination with a chronic inflammatory disease would lead to what diagnosis?

Answer 15

AA or secondary systemic amyloidosis

Question 16

What type of amyloid is most often associated with AD?

Answer 16

beta amyloid

Question 17

Build up of a serum protein that binds/transports thyroxine and retinol in heritable neuropathic/cardiomyopathic amyloidosis is due to what?

Answer 17

mutation in the gene for TTR (transthyretin)

Question 18

What type of amyloidosis is primarily associated with long term dialysis?

Answer 18

beta 2 microglobulin

Question 19

Genetic mutation 11e122 causes what?

Answer 19

late onset cardiac amyloidosis with restrictive cardiomyopathy and arrhythmia

Question 20

What are the most common organs to be affected by amyloidosis?

Answer 20

kidney
heart
liver