Transplantation

Question 1

What is xenograft?

Answer 1

Transplant across different species

E.g. Porcine heart valve for human

Question 2

What is Allograft?

Answer 2

Transplant within the same species

Question 3

What is Autograft?

Answer 3

Transplant within the same individual

Question 4

What is immunological significance of transplantation?

Answer 4

It is important to consider >>> “whether the transplant is immunogenic”

If yes >>> consider “immunosupression by drugs”

Question 5

Are cardiac valve transplants immunogenic?

Answer 5

No

Cardiac valve transplants are not immunogenic.

So, they do NOT require immunosupression.

Question 6

Are all transplanted tissues immunogenic?

Answer 6

Almost all

(except. cardiac valve transplants)

Question 7

Do all transplanted tissues require immunosupression?

Answer 7

Almost all

(except. cardiac valve transplants)

Question 8

Why do we use immunosupression in the setting of an organ transplant?

Answer 8

To prevent host rejection

Question 9

Why do we use immunosupression in the setting of a bone marrow transplant?

Answer 9

To prevent GVHD (graft vs host disease)

(Here immune system is the organ that has been transplanted)

Question 10

Key principle to minimise the risk of host-rejection before transplantation of a tissue/organ

Answer 10

Match HLA genotype (as closely as possible)

Question 11

The importance of HLA matching depends upon-?

Answer 11

The “immunogenicity” of the tissue being trasnplanted

Question 12

Importance of HLA matching in renal transplantation and liver transplantation

Answer 12

• More important for renal transplantation
• Relatively unimportant for liver transplantation

Question 13

Types of transplant rejection

Answer 13

• Hyperacute
• Acute
• Chronic

Question 14

Hyperacute transplant rejection: mechanism

Answer 14

Pre-existing humoral immunity

Question 15

Acute transplant rejection: mechanism

Answer 15

T cell driven/mediated

Question 16

Chronic transplant rejection: mechanism

Answer 16

Variable

(Includes: non-compliance with medication)

Question 17

Hyperacute transplant rejection: Time of onset

Answer 17

Immediate (i.e. while still on the operating table)

Question 18

Acute transplant rejection: Time of onset

Answer 18

Weeks to months

Question 19

Chronic transplant rejection: Time of onset

Answer 19

Months to years

Question 20

Hyperacute transplant rejection: Clinical features

Answer 20

Severe systemic inflammatory response

Question 21

Acute transplant rejection: Clinical features

Answer 21

Most patients experience some form of acute rejection

But when it is severe form >> characterised by >>

• Photosensitive rash
• Abdominal pain
• Jaundice

Question 22

Chronic transplant rejection: Clinical features

Answer 22

But it occurs after “repeated episodes” of acute rejection

= means repeated episodes of features of acute rejection

• photosensitive rash
• abdominal pain
• jaundice

A problem specially with “lung transplantion”

Question 23

Which type of transplant rejection is more common (than other types) in lung transplantation?

Answer 23

Chronic transplant rejection (Repeated episodes of acute rejection)

Question 24

Do cardiac valve transplantation need immunosupression/immunosupressive drugs?

Answer 24

NO

Because they are NOT immunogenic