1. Hong Kong Workshop Lecture 3 Antigenicity of HLA-DRDQDP Epitopes

2. Class II HLA Antibodies Decrease Transplant Success
DRB1 is “standard” for donor-recipient matching
DRB3/4/5
Antibodies to DR51, DR52 and DR53
DQB1 and DQA1
Relevance of DQB matching in transplantation
Patients make antibodies to DQB and DQA epitopes
DPA1 and DPB1
Relevance of DP matching
Anti-DP antibodies in transplantation

3. Topography of Polymorphic Residues on HLA-DR and HLA-DQ Molecules1 1 1 1 2 2 2 2

4. Class II Eplet Version of HLAMatchmaker
Duquesnoy, RJ and Askar, M: HLAMatchmaker: A Molecularly Based Algorithm for Histocompatibility Determination. V. Eplet Matching for HLA-DR, HLA-DQ and HLA-DP, Human Immunology, 68: 12-25, 2007

5. Polymorphic positions are underlined
3.0 Angstrom Patches on
DRB1,3,4,5
Polymorphic positions are underlined

6. DRB1,3,4,5
Contd

7. Polymorphic Residue Positions in 3 Angstrom DRB Patches

8. Polymorphic Residues Positions in 3 Angstrom DQ and DP Patches
DQB
DPA
DPB
Polymorphic Residues Positions
in 3 Angstrom DQ and DP Patches

9. Determination of the Polymorphic Residue Composition of Each Patch
HLA Patch Generator: a Microsoft Excel Macro developed by Grzegorz Dudek (now at Czestchowa University of Technology, Poland)

10. Eplet Numbers on HLA Class II Molecules
Locus
# Eplets
DRB
149
DQB 74
DQA 58
DPB 45
DPA 19
Duquesnoy and Askar, Human Immunology, 68: 12-25, 2007

11. Class II Epitope Studies by Terasaki’s group
Deng CT, Cai J, Tarsitani C, El-Awar N, Lachmann N, Ozawa M. HLA Class II DQ Epitopes. Clinical Tramsplants :
Deng CT, El-Awar N, Ozawa M, et al. Human leukocyte antigen class II DQ alpha and beta epitopes identified from sera of kidney allograft recipients. Transplantation. 2008;86:452-9.
El-Awar N, Terasaki PI, Cai J, et al. Epitopes of the HLA-A, B, C, DR, DQ and MICA antigens. Clinical Transplants. 2007:
Cai J, Terasaki PI, Mao Q, et al. Development of nondonor-specific HLA-DR antibodies in allograft recipients is associated with shared epitopes with mismatched donor DR antigens. American Journal of Transplantation. 2006;6:
Cai J, Kohanof S, Terasaki P. HLA-DR Antibody Epitopes. In: Checka MaT, PI, ed. Clinical Transplants Los Angeles, CA: Tearasaki Foundation Laboratory, 2006:

12. * Marrari M and Duquesnoy RJ, Tissue Antigens, 74:134-146, 2009.
Comparison between Terasaki’s Class II epitopes HLAMatchmaker-defined eplets
Locus
TerEps
Eplets
Eplet pairs
Eplets with
substitutions
No eplets DR 60 45 3 12 2 DQ 18 13 1
* Marrari M and Duquesnoy RJ, Tissue Antigens, 74: , 2009.

13. Molecular locations of eplet equivalents of Terasaki’s DRB Epitopes

14. Molecular locations of eplet equivalents of Terasaki’s DQA and DQB Epitopes

15. Class II Eplet Examples In HLA Epitope Registry
Locus
Eplet
Description
Eplet-Carrying Alleles in Luminex Panel
DRB
12TSE
12T,13S,14E
DRB1*01:01/02/03,09:01/02,10:01
57V
57V,58A,60S
DRB1*07:01,09:01,12:01;B3*01:01,03:01
Locus
Eplet
Description
Eplet-Carrying Alleles in Luminex Panel
DQB
56PA
56P,57A
DQB1*02:01, 02:02, 03:02
DQA
41RA2
40E,41R,45A / 129Q,130S
DQA1*01:01, 01:02, 01:04
Locus
Eplet
Description
Eplet-Carrying Alleles in Luminex Panel
DPB
65LK
65L,69K
DPB1*03,*14,*28
56EE
56EEDR11
55D,56E,57E
55D,56E,57E*
*DR11 has 57D,58E,59E
DPB1*02:01,*04:02,*08,*10,*18,*28
DPB1*02:01,*04:02,*08,*10,*18,*28 and DR11
DPA
50RA
50R,51A
DPA1*02:01,02:02,*04:01 11

16. Antibody Verification of HLA Epitopes
Duquesnoy RJ, Marrari M, Mulder A, da M. Sousa LCD, Da Silva AS, do Monte SJH. ‘First Report on the Antibody Verification of HLA-ABC Epitopes Recorded in the HLA Epitope Registry’. Tissue Antigens 83: , 2014
97 HLA-ABC antibody-verified epitopes have been recorded, 62 correspond to eplets and 35 are defined by eplets paired with other residue configurations
Duquesnoy RJ, Marrari M, Tambur A, da Mata Sousa LCD, Da Silva AS, do Monte SJH. ‘First Report on the Antibody Verification of HLA-DR, HLA-DQ and HLA-DP Epitopes Recorded in the HLA Epitope Registry’ Human Immunology 75: ,
24 HLA-DRB1/3/4/5, 15 DQB, 3 DQA and 8 DPB antibody-verified epitopes
Duquesnoy RJ, Marrari M, Mostecki J, Da Silva AS, da Mata Sousa LCD, do Monte SJH. ‘First Report on the Antibody Verification of MICA Epitopes Recorded in the HLA Epitope Registry ‘ Int J Immunogenetics 41: , 2014
21 MICA epitopes verified with antibodies which have primarily been tested in Luminex assays with single alleles

17. Two examples of antibody-verified DRB epitopes
High frequency epitope

18. Serum antibodies against antibody-verified epitopes on DQB and DQA

19. Marrari and Duquesnoy Human Immunology, 70:403-9, 2009
DRB Epitope Clinical Study Why can Sensitization by a HLA-DR2 Mismatch lead to Antibodies that react also with HLA-DR1?
Marrari and Duquesnoy Human Immunology, 70:403-9, 2009

20. 15th International Histocompatibility Workshop Project on HLA Epitope Immunogenicity
A multilaboratory collaborative project to characterize these epitopes and also how often they induce specific antibodies in patients with rejected kidney transplants
Serum analyses on more than 150 allograft nephrectomy cases contributed so far by more than 25 laboratories worldwide have yielded interesting information that has led to a better understanding of antibody recognition of HLA epitopes
This report address the question how a single DR2 mismatch can lead to antibodies that also react with DR1
Although DR1 and DR2 might share an epitope recognized by these antibodies, this interpretation is incorrect
An HLAMatchmaker analysis offers a clearly different explanation

21. 19 Allograft Nephrectomy Cases with DR2 or DR1 Mismatches in 15th International Workshop Project on Epitope Immunogenicity

22. Case contributed by Andrew Lobashevsky, Indianapolis Transplant Center
Example of an antibody response to a DR15 mismatch Patient type: DRB1*0301, DRB1*0801; DRB3*0101 Immunizing donor: DRB1*1501, DRB5*0101
Case contributed by Andrew Lobashevsky, Indianapolis Transplant Center

23. Case contributed by Andrew Lobashevsky, Indianapolis Transplant Center
Example of an antibody response to a DR15 mismatch Patient type: DRB1*0301, DRB1*0801; DRB3*0101 Immunizing donor: DRB1*1501, DRB5*0101
Case contributed by Andrew Lobashevsky, Indianapolis Transplant Center

24. Case contributed by Andrew Lobashevsky, Indianapolis Transplant Center
Example of an antibody response to a DR15 mismatch Patient type: DRB1*0301, DRB1*0801; DRB3*0101 Immunizing donor: DRB1*1501, DRB5*0101
Case contributed by Andrew Lobashevsky, Indianapolis Transplant Center

25. Case contributed by Andrew Lobashevsky, Indianapolis Transplant Center
Example of an antibody response to a DR15 mismatch Patient type: DRB1*0301, DRB1*0801; DRB3*0101 Immunizing donor: DRB1*1501, DRB5*0101
Case contributed by Andrew Lobashevsky, Indianapolis Transplant Center

26. Example of an antibody response to a DR1 mismatch Patient type: DRB1
Example of an antibody response to a DR1 mismatch Patient type: DRB1*0701, DRB1*1401; DRB3*0202, DRB4*0101 Immunizer: DRB1*0101
Case contributed by Silvia Chrenova, Slovak Medical University, Bratislava, Slovakia

27. 96EV is an immunogenic eplet shared by DR1 and DR51
Sensitization
induced by
DR51
Antibodies
to 96EV
DR15
DRB5*0101
7/9 cases
DR16
DRB5*0202
2/2 cases
DR1
None
8/8 cases
Total
17/19 cases
90%

28. Further support of the 96EV epitope
Monoclonal antibody 137BL7
Loh MT, Chan SH and Ren EC: A monoclonal antibody with specificity to the HLA-DR1 and -DR51 antigens. Tissue Antigens. 42:100-4, 1993
Monoclonal antibody against epitope #1055 shared between DR1 and DR51
Cai J, Kohanof S and Terasaki P: HLA-DR Antibody Epitopes. Clinical Transplants 2006, p 103.

29. Marrari and Duquesnoy Human Immunology, 70:403-9, 2009
Conclusions
These findings demonstrate the importance of DR51 in determining mismatch acceptability of DR1 and DR2
Exposure to DR2-DR51 may lead to anti-96EV antibodies that render DR1 as an unacceptable mismatch
Exposure the DR1 may also lead to anti-96EV antibodies that render DR51 as an unacceptable mismatch. Consequently, all DR2-DR51 haplotypes should be considered as unacceptable mismatches
This study provides further support of the usefulness of HLAMatchmaker in determining mismatch acceptability
Marrari and Duquesnoy Human Immunology, 70:403-9, 2009

30. Antibody-verified DQ epitopes in the HLA Epitope Registry

31. Antibody Reactivity with Epitopes on HLA-DQ Heterodimers Anat R Tambur, Northwestern University
Sample size: Sera from 104 patients awaiting renal TX, with known history of antibodies to DQ antigens 76(73%) have anti-DQ antibodies How frequent are antibodies against “self” DQ component? 37 (36%): Own DQB1 with non-self DQA1 60 (58%):Own DQA1 with non-self DQB1 26 (25%):Antibodies to both groups of molecules DQ epitopes can comprise pairs of DQA + DQB eplets Antibody reactivity should be assessed with DQ heterodimers rather than individual DQA and DQB chains

32. Antibody-verified DPB epitopes in the HLA Epitope Registry

33. Cross-reactivity between DR11 and certain DPB alleles

34. Cross-reactivity between DR11 and certain DPB alleles

35. Cross-reactivity between DR11 and certain DPB alleles