Organ Transplant

Question 1

Types of transplants :

Answer 1

🔸Autograft : tissue graft from one point to another from the same individual’s body
🔸Allograft : tissue graft from a donor from the same species but not genetically identical
🔸Isograft: a graft of tissue btw 2 individuals who are genetically identical
🔸xenograft : tissue graft from a donor of a different species and xenotransplantation
🔸Split trnasplant
🔸Domino transplants

Question 2

Splint transplants :

Answer 2

Sometimes a deceased donor organ ( specially of the liver ) may be divided between 2 recipients specially an adult and child

Question 3

Domino transplants :

Answer 3

• this operation is usually done for cystic fibrosis as both lungs need to be replaced and it is a technically easier operation to replace heart and lungs
• this is also used for a special form of liver transplant , in which the recipient suffers from FAMILIAL AMYLOIDOTIC POLYNEUROPATHY in which the liver produces a protein that damages other organs

Question 4

HLA can initiate rejection and graft damage via humoral or cellular mechanisms

Answer 4

Humoral rejection= mediated by recipient’s Ab
Cellular rejection= is the more common type of rejection after organ transplant. Mediated by T lymphocytes, it results from their activation and proliferation after exposure to donor MHC molecules

Question 5

What are types of rejection:

Answer 5

1) Host vs Graft=
▪️hyperacute rejection ( min-hrs)
▪️acute rejection( days-wks)
▪️chronic rejection( months/yrs) 
2)graft Vs host

Question 6

Signs and sympts of transplant rejection:

Answer 6

• pain at the site of the transplant
• feeling ill
• flu-like sympts
• fever
• weight gain
• swelling
• decreased urine output

Question 7

Methods for increasing graft survival:

Answer 7

1) minimization of the HLA disparity btw donor and recipient
2) immunosuppressive therapy : drugs such as AZATHIOPRINE, STEROIDS, CYCLOSPORINE

Question 8

GVH- graft Vs host reaction:

Answer 8

An immunologically competent graft is transplanted into an immunologically suppressed recipient
-the grafted cells survive and react against the host cells
🔸characterized by: fever, pancytopenia, wL, rash , diarrhea , hepatosplenomegaly and death

Question 9

Primary anti rejection therapies;

Answer 9

1) corticosteroids
2) anti-proliferatives
3) tcell signaling/ activation disruptors

Question 10

Organ perfusion prior to transplant ( to minimize rejection ) :
What are some experimental anti rejection therapies?

Answer 10

1) bone marrow HSC transplants
2) thymic manipulation
3) T reg cell induction

Question 11

Immunosuppressive therapy;:

Answer 11

🔸triple therapy ( all po/ iv) 
-cyclosporine
-corticosteroids
-cytotoxic drug 
🔸monoclonal Abs: muromonab CD3 
🔸polyclonal Abs: Atgam

Question 12

Indications for kidney transplantation:

Answer 12

1) chronic glomerulonephritis
2) diabetic nephropathy
3) nephroangiosclerosis
3) chronic pyelonephritis
4) polycystic kidney
5) displasia

Question 13

Kidney transplant operation:

Answer 13

• transplanted kidney’s artery and vein attached to recipient’s iliac
• an incision is made in bladder and ureter is attached