Transplantation

Question 1

TYPES OF GRAFTS

Answer 1

Based on Foreignness

GRAFT ORIGIN&raquo_space;living or cadaver (من ميت)

GRAFT IMMUNOGENICITY» The difference in the expression of HLA class II molecules
Lack in some tissues of suitable APCs (BM Skin liver )

Question 2

Histocompatibility antigens definition & main 2 systems ?

Answer 2

that determine the compatibility (or incompatibility) of transplanted tissue.

MHC (Major histocompatibility complex; HLA in humans)
ABO blood group system

Question 3

Major transplantation antigen
Class l ……&……Ag
Class ll……….Ag

Answer 3

A/B
DR

Question 4

INDUCTION OF IMMUNE RESPONSES TO TRANSPLANTS (how does the rejection happen)?

Answer 4

1-direct recognition of donor Mhc (APC حقت ال donor )

Indirect Allorecognition (APC حقت الجسم)

Question 5

The immune response is mainly——

Answer 5

CMIR → cd 8(CTL) non specific killers

Question 6

Count Immune mechanism of graft rejection?

Answer 6

Hyper acute, acute/ chronic

Question 7

Within minutes, circulating preformedanti-abo or anti-hla abs, 2ry hmir /type Il hsr / no ttt/ prevented by propermatch

Mechanism
1. Preformed Ab,
2. complement activation,
3. neutrophil margination,
4. inflammation,
5. Thrombosis formation

Answer 7

Hyper acute

Question 8

Days to weeks / inadequate immunosappressions 1ry c.m.i.r(type 4 dhsr )/ treatment by immunosuppression

Mechanism

T-cell, and macrophage,
Myocyte and endothelial damage,
Inflammation

Answer 8

Acute

Question 9

Months to~years/ chronic d.t.h (type 4 h.s.r)/no ttt
Mechanism

1. Macrophage–T-cell mediated
2. Concentric medial hyperplasia
3. Chronic DTH reaction

Answer 9

Chronic rejection

Question 10

PREVENTION OF GRAFT REJECTION

Answer 10

1. Donor/recipient matching (histocompatibility testing)

Recipient preparation

Immunosuppression

Question 11

Histocompatibility testing ……………..+…………….→ ………………… , ……………… , ………………..

Answer 11

ABO typing +
HLA testing →

1- h.l.a typing (microlymphocytotoxicity testing)+ HLA Molecular typing(PCR, ↑sensitivity, ↓time )/

2- HLA ab detection ( WBCs CROSSMATCH + ELISA+ Flowcytometry)

3- Mixed Lymphocyte culture

Question 12

How to prepare a Recipient??

Answer 12

Treatment of hypertension if present
• Treatment of infections if present.
• Prophylactic antibiotics.
• Vaccination
• Blood transfusion from donor to recipient→
Induce tolerance

Pre-transplantation immunosuppressive
therapy

Question 13

There are special problems associated with bone marrow transplantation BMT

In leukemia therapy, the recipient’s hematopoietic system, the source of the leukemia, must first be destroyed by aggressive cytotoxic chemotherapy. The patient is thus……………………………….

Bone marrow cells are………………. and can thus elicit a strong immune response. Very careful donor/recipient HLA matching is therefore critical

Answer 13

severely immunocompromised.

highly immunogenic

Question 14

If mature donor T cells are transplanted with the marrow cells, these mature T cells recognize the tissues of the recipient as foreign, causing a severe inflammatory disease called……………………………………and is the most serious complication of BMT and is characterized by……………..,………….,……….,………..,……… eventually death

Answer 14

graft-versus-host disease (GVHD).

rashes, diarrhea, and pneumonitiIs, liver dysfunction,wasting