1. Tissue Typing & Cross Matching - Recent Advances

2. Transplantation Immunology
MHC and Tissue Matching
Graft Rejection
Immuno-suppression

3. Blood Transfusion
First attempts were unsuccesful (MISMATCH)
Discovery of blood groups (Red cell antigens)
A-B Landsteiner 1900
Rh Levine, Stetson 1939
Succesful transfusion = Transplantation
Others: Bone, Tissue-engineering, etc
Transplantation
Organ Transplantation

5. Classification of Renal Transplantation
Auto-RT
Cadaveric
Allograft RT
Living Donor
Xenograft RT (In experimental)
Related
Unrelated

6. Transplantation History
experimental kidney transplantation -1912
Alexis Carel-Nobel prize
1935 human kidney transplant in Russia - rejection
P.B. Medawar (1945) skin grafts
Self skin accepted
Relative not accepted !  What is the difference ?
 Immunologic mechanism
A. Mitchison (1950)
Lymphocytes are responsible for rejection

7. Transplantation History
Peter Gorer (~1935)
Identification of 4 group of genes for RBC
Gorer and Gorge Snell (~1950)
Group II antigens are responsible for rejection
 Major HistoCompatibility genes (HLA)
Nobel prize 1980 George Snell
1954 Succesful kidney transplant between identical twins in Boston – Peter Bent Brigham Hospital
Joseph Murray 1991 Nobel prize

8. HISTORY OF RT 1933 First clinical RT (Voronov);
1954 First long-term successful RT(Twin);
1958 Discovery of HLA(Human Lym Antigen);
1959 Radiation be used for immuno-
suppression;
1961 Azathioprine (Aza);
1962 Prednisolone; Tissue Matching;
1966 Cross-Matching;
Late 1960’ Preservation the Kidney>24hr ;;
1978 Clinical use of Cyclosporine(CsA).

9. Key factors for succesful transplantation
Knowledge of MHC haplotypes
Effective immunosuppression
Ability to identify and treat infections
Available donors

10. Pre-OP Selection ABO Blood Group: Compatible; Cytotoxicity Test:
Donor Lymphocyte Recipient Serum
Cross matching
Donor Serum Recipient’s Lymphocyte
Mixed Lymphocyte Culture
Tissue typing (HLA)

11. Transplantation Immunology

13. Histocompatibility Antigens
Major histocompatibility antigens
MHC class I molecules : almost all nucleated cells
MHC class II molecules : APCs, endothelium of renal arteries and glomeruli
Minor histocompatibility antigens : H-Y molecule

14. Major histocompatibility antigens
Human leukocytic Antigen
HLA I. (α1, α2, α3, β2-microglobulin)
Gene-Code alleles: A, B, C loci
HLA II. (α1, α2, β1, β2)
Gene-Code alleles: DP, DQ, DR loci
HLA III.
Gene-Code alleles: C4A, TNF, HSP70
MHC complex: Gene

15. Major histocompatibility antigens
MHC loci are highly polymorphic
Many alternative alleles at a locus
The loci are closely linked to each other
A set of alleles is called a HAPLOTYPE
One inherites a haplotype from mother and another from father
The alleles are codominantly expressed

16. Inheritance of MHC alleles
Mother
Father
A/B
C/D
A/C A/D B/C B/D A/R R2/C R2/R1
Possible children of parents with HLA haplotype A/B and C/D
R1=C-D recombination
R2=A-B recombination

17. Induction of Immune Responses Against Transplants
alloantigens and xenoantigens : antigens that serve as the targets of rejection
the antibodies and T cells that react against these antigens are said to be alloreactive and xenoreactive, respectively.
allorecognition
direct
indirect

20. Rejection
From: Kuby: IMMUNOLOGY (fourth edition, 2000)

21. Tissue typing Microcytotoxicity assay
Known antibody to WBCs of donor / recipient
Complement mediated lysis if Ab present on cell surface
Mixed lymphocyte culture (MLC)
Irradiated donor lymphocytes (stimulants)
Incubated with recipient lymphocytes
3H Thymidin incorporatin measured
Flow cytometry cross typing
DNA analysis
Genomic typing (very precise, many subtipes)

23. From which animals are we able to transplant organs
3. The Pig:
Surprisingly similar to our anatomy and physiology
1. The Chimpanzee:
Its DNA sequence differs from ours by only 2%
2. The Baboon:
Its organs are too small for a large adult human

24. Organ breeding:
A transgenic animal carries a foreign gene inserted into its genome.
The transgenic animal shows the specific characteristics which are coded on the inserted gene
 A gene which is responsible for the construction of a human organ makes the organism produce the organ additionally.

25. The insert of a foreign gene into an animal
I. DNA microinjection
The DNA is inserted into the cell with a small syringe
II. Retrovirus gene transfer
The DNA is carried into a cell by a virus.

26. Suppression of immune system rejection
The genes which are responsible for the own tissue not being rejected can be injected into an animal embryo
the organs of which are then similar to the ones of the human.
It is possible to humanize the bred organs by making certain genetic modifications.
Then the organs are accepted by the immune system.

27. Transplantation-background
Worse outcome for Rh-mismatched recipients— Rh(D)-positive donor into a Rh(D)-negative recipient— 12 months posttransplant
Clinical transplants Los Angeles, UCLA Tissue Typing Laboratory1988, p 409.
Rh(D) mismatch had a negative impact on long-term graft survival in cadaveric renal transplantation
Transplantation 1998; 65: 588.
Solid organ transplantation ABO blood group compatibility, but the Rh(D) compatibility is an relevant obstacle .

28. Transplantation – Graft survival

29. Transplantation - Patient survival

30. Transplantation: Conclusion
Rh incompatibility is not detrimental in live-donor renal transplantation.

31. Transfusion and Transplantation Conclusion
Pre-transfusion compatibility testing only ABO grouping, antibody screening and a major cross-match, and D typing being discontinued
Rh incompatibility is not detrimental in transplantation.

32. CONTRAINDICATIONS TO RENAL TRANSPLANTATION
ABO incompatibility.
Cystoxic antibodies against HLA antigens of donor.
Recent or metastatic malignancy.
Active infection.
AIDS.
Severe extrarenal disease (cardiac, pulmonary, hepatic).
Active vasculitis or glomeulonephritis.
Uncorrectable lower urinary tract disease.
Noncompliance.
Psychiatric illness including alcoholism and drug addiction.
Morbid obesity.
Age > 70 years.
Primary oxalosis.
Persistent coagulation disorder. 32

33. Matching between Recipient And Donor
A- Tissue typing
Determined by 6 antigens located on cell surface encoded for by the HLA gene located on the short arm of chromosome 6.
Class I antigens (HLA-A and HLA-B) are expressed on the surface of most nucleated cells.
Class II antigen (HLA-DR) are expressed on surface of APC and activated lymphocytes.
These 6 antigens are referred to as major transplant antigens.
The match between donor and recipient can range from 0 to six. 33

34. Matching between Recepient And Donor
B- Cross matching
A laboratory test that determines weather a potential transplant recipient has preformed antibodies against the HLA antigens of the potential donor. (Donor Lymphocytes + Recipient Serum)
A Final CM is mandatory
C- Compatible ABO blood group. 34

35. Structure of the HLA class I and class II antigens.35

36. Organization of the human HLA genes on chromosome 6.36

37. Effect Of HLA Matching On The Graft Outcome
Data from large registries indicate that, the better the HLA-match, the better the long-term survival of the allograft.
The benefits of matching are particularly noteworthy in recipients of kidneys from donors with zero mismatch.
The benefits of lesser degrees of matching have become less obvious with the use of newer and more potent immunosuppressive drugs.
Matching for DR antigens are more favorable than others. 37

38. The beneficial effect of HLA B and DR matching in patients with and without the benefit of cyclosporine. 38

39. Factors Influencing The Longivity Of Renal Allograft
Age
HLA matching
Delayed graft function
Ischemia time.
Number of acute rejection episodes.
Native kidney disease.
Ethnicity.
Others 39

40. Relative incidence of causes of allograft dysfunction during the year following transplantation.40

41. Immune responses to renal allograft41

42. Recent advances
Over the past several years, significant advances in HLA antibody detection have occurred
Solid-phase, multiplex testing platforms have replaced traditional cell-based assays, and have provided better sensitivity and specificity in antibody detection
As a direct result of improved antibody identification, many programs are moving into the realm of the 'virtual cross-match'

43. The Virtual Cross-match
The virtual cross-match has proven to be successful in renal, cardiac and lung transplantation, and has resulted in a greater percentage of sensitized patients gaining access to transplantation
Virtual cross-matching allows patients better access to transplantation and enhances patient care

44. Conclusion
Transplantation provides us the means of restoring the function of a nonfunctional organ.
In the case of BMT it enables us to administer such high doses of chemotherapy that would destroy the BM as well as the residual tumor.
A lot immunologic knowledge had to be collected to understand what is happening.

45. Conclusion
HLA typing and matching is essential for allograft transplantation.
Effective immunosuppressive therapy (Cyclosporin) revolutionised organ transplantation.
The future is to transplant cells, that would restore the function of the affected organ.
Gene therapy is growing, and will cause another revolution like cyclosporin did in the 1980s.