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Gramkow AM, Baatrup JH, Gramkow ET, Thiesson HC, Koefoed-Nielsen P. Association of HLA B- and T-cell molecular mismatches with HLA antibodies, rejection, and graft survival in pediatric kidney transplantation. Pediatr Transplant 2024; 28:e14773. [PMID: 38808702 DOI: 10.1111/petr.14773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 04/01/2024] [Accepted: 04/18/2024] [Indexed: 05/30/2024]
Abstract
BACKGROUND Optimizing graft survival and diminishing human leukocyte antigen (HLA) sensitization are essential for pediatric kidney transplant recipients. More precise HLA matching predicting epitope mismatches could reduce alloreactivity. We investigated the association of predicted HLA B- and T-cell molecular mismatches with the formation of de novo donor-specific antibodies, HLA antibodies, rejection, and graft survival. METHODS Forty-nine pediatric kidney transplant recipients transplanted from 2009 to 2020 were retrospectively studied. Donors and recipients were high-resolution HLA typed, and recipients were screened for HLA antibodies posttransplant. HLA-EMMA (HLA Epitope MisMatch Algorithm) and PIRCHE-II (Predicted Indirectly ReCognizable HLA Epitopes) predicted the molecular mismatches. The association of molecular mismatches and the end-points was explored with logistic regression. RESULTS Five recipients (11%) developed de novo donor-specific antibodies. All five had de novo donor-specific antibodies against HLA class II, with four having HLA-DQ antibodies. We found no associations between PIRCHE-II or HLA-EMMA with de novo donor-specific antibodies, HLA sensitization, graft loss, or rejection. However, we did see a tendency towards an increased odds ratio in PIRCHE-II predicting de novo donor-specific antibodies formation, with an odds ratio of 1.12 (95% CI: 0.99; 1.28) on HLA class II. CONCLUSION While the study revealed no significant associations between the number of molecular mismatches and outcomes, a notable trend was observed - indicating a reduced risk of dnDSA formation with improved molecular match. It is important to acknowledge, however, that the modest population size and limited observed outcomes preclude us from making definitive conclusions.
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Affiliation(s)
- Ann-Maria Gramkow
- Department of Nephrology, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Johanne H Baatrup
- Department of Clinical Immunology, Aarhus University Hospital, Aarhus, Denmark
| | - Emilie T Gramkow
- Department of Nephrology, Odense University Hospital, Odense, Denmark
- Department of Molecular Medicine - Cancer and Inflammation, University of Southern Denmark, Odense, Denmark
| | - Helle C Thiesson
- Department of Nephrology, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, University of Southern Denmark, Odense, Denmark
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Devriese M, Lemonnier FA, Lion J, Sayegh C, Fleury E, Shofstall C, Giraldo L, Fiachetti Q, Usureau C, Miyadera H, Toutirais O, Mooney N, Lowe D, Taupin JL. Separating the Wheat from the Chaff among HLA-DQ Eplets. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2024; 212:1981-1991. [PMID: 38647382 DOI: 10.4049/jimmunol.2400030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Accepted: 04/02/2024] [Indexed: 04/25/2024]
Abstract
In transplantation, anti-HLA Abs, especially targeting the DQ locus, are well-known to lead to rejection. These Abs identified by Luminex single Ag assays recognize polymorphic amino acids on HLA, named eplets. The HLA Eplet Registry included 83 DQ eplets, mainly deduced from amino acid sequence alignments, among which 66 have not been experimentally verified. Because eplet mismatch load may improve organ allocation and transplant outcomes, it is imperative to confirm the genuine reactivity of eplets to validate this approach. Our study aimed to confirm 29 nonverified eplets, using adsorption of eplet-positive patients' sera on human spleen mononuclear cells and on transfected murine cell clones expressing a unique DQα- and DQβ-chain combination. In addition, we compared the positive beads patterns obtained in the two commercially available Luminex single Ag assays. Among the 29 nonverified DQ eplets studied, 24 were confirmed by this strategy, including the 7 DQα eplets 40E, 40ERV, 75I, 76 V, 129H, 129QS, and 130A and the 17 DQβ eplets 3P, 23L, 45G, 56L, 57 V, 66DR, 66ER, 67VG, 70GT, 74EL, 86A, 87F, 125G, 130R, 135D, 167R, and 185I. However, adsorption results did not allow us to conclude for the five eplets 66IT, 75S, 160D, 175E, and 185T.
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Affiliation(s)
- Magali Devriese
- Laboratoire d'Immunologie et Histocompatibilité, Hôpital Saint Louis, Paris, France
- INSERM UMRS 976, Institut de Recherche Saint-Louis, Université Paris Cité, Paris, France
| | | | - Julien Lion
- INSERM UMRS 976, Institut de Recherche Saint-Louis, Université Paris Cité, Paris, France
| | - Caroline Sayegh
- Laboratoire d'Immunologie et Histocompatibilité, Hôpital Saint Louis, Paris, France
- INSERM UMRS 976, Institut de Recherche Saint-Louis, Université Paris Cité, Paris, France
| | - Emma Fleury
- Laboratoire d'Immunologie et Histocompatibilité, Hôpital Saint Louis, Paris, France
| | - Catherine Shofstall
- Laboratoire d'Immunologie et Histocompatibilité, Hôpital Saint Louis, Paris, France
| | - Lisa Giraldo
- INSERM UMRS 976, Institut de Recherche Saint-Louis, Université Paris Cité, Paris, France
| | - Quentin Fiachetti
- Laboratoire d'Immunologie et Histocompatibilité, Hôpital Saint Louis, Paris, France
| | - Cédric Usureau
- Laboratoire d'Immunologie et Histocompatibilité, Hôpital Saint Louis, Paris, France
- INSERM UMRS 976, Institut de Recherche Saint-Louis, Université Paris Cité, Paris, France
| | - Hiroko Miyadera
- Department of Medical Genetics, University of Tsukuba, Ibaraki, Japan
| | - Olivier Toutirais
- Laboratoire d'Immunologie et d'Histocompatibilité, CHU de Caen, Caen, France
| | - Nuala Mooney
- INSERM UMRS 976, Institut de Recherche Saint-Louis, Université Paris Cité, Paris, France
| | - Dave Lowe
- Department of Research and Development, One Lambda, West Hills, CA
| | - Jean-Luc Taupin
- Laboratoire d'Immunologie et Histocompatibilité, Hôpital Saint Louis, Paris, France
- INSERM UMRS 976, Institut de Recherche Saint-Louis, Université Paris Cité, Paris, France
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Mankowski MA, Gragert L, Segev DL, Montgomery R, Gentry SE, Mangiola M. Balancing Equity and HLA Matching in Deceased-Donor Kidney Allocation with Eplet Mismatch. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2024:2024.06.13.23290644. [PMID: 38947023 PMCID: PMC11213093 DOI: 10.1101/2024.06.13.23290644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/02/2024]
Abstract
Background Prioritization of HLA antigen-level matching in the US kidney allocation system intends to improve post-transplant survival but causes racial disparities and thus has been substantially de-emphasized. Recently, molecular matching based on eplets has been found to improve risk stratification compared to antigen matching. Methods To assign eplets unambiguously, we utilized a cohort of 5193 individuals with high resolution allele-level HLA genotypes from the National Kidney Registry. Using repeated random sampling to simulate donor-recipient genotype pairings based on the ethnic composition of the historical US deceased donor pool, we profiled the percentage of well-matched donors for candidates by ethnicity. Results The percentage of well-matched donors with zero-DR/DQ eplet mismatch was 3-fold less racially disparate for Black and Asian candidates than percentage of donors with zero-ABDR antigen mismatches, and 2-fold less racially disparate for Latino candidates. For other HLA antigen and eplet mismatch thresholds, the percentage of well-matched donors was more similar across candidate ethnic groups. Conclusions Compared to the current zero-ABDR antigen mismatch, prioritizing a zero-DR/DQ eplet mismatch in allocation would decrease racial disparities and increase the percentage of well-matched donors. High resolution HLA deceased donor genotyping would enable unambiguous assignment of eplets to operationalize molecular mismatch metrics in allocation. Key Points Question: What is the impact of prioritizing low molecular mismatch transplants on racial and ethnic disparities in US deceased-donor kidney allocation, compared to the current prioritization of antigen-level matching?Findings: The lowest-risk eplet mismatch approach decreases racial disparities up to 3-fold compared to lowest-risk antigen mismatch and identifies a larger number of the lowest allo-immune risk donors.Meaning: Prioritizing eplet matching in kidney transplant allocation could both improve outcomes and reduce racial disparities compared to the current antigen matching.
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4
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Jabbour R, Heinzel A, Reindl-Schwaighofer R, Gregorich MG, Regele H, Kozakowski N, Kläger J, Fischer G, Kainz A, Becker JU, Wiebe C, Oberbauer R. Early progression of chronic histologic lesions in kidney transplant biopsies is not associated with HLA histocompatibility. Nephrol Dial Transplant 2024; 39:808-817. [PMID: 37960919 PMCID: PMC11181859 DOI: 10.1093/ndt/gfad246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Indexed: 11/15/2023] Open
Abstract
BACKGROUND Early progression of chronic histologic lesions in kidney allografts represents the main finding in graft attrition. The objective of this retrospective cohort study was to elucidate whether HLA histocompatibility is associated with progression of chronic histologic lesions in the first year post-transplant. Established associations of de novo donor-specific antibody (dnDSA) formation with HLA mismatch and microvascular inflammation (MVI) were calculated to allow for comparability with other study cohorts. METHODS We included 117 adult kidney transplant recipients, transplanted between 2016 and 2020 from predominantly deceased donors, who had surveillance biopsies at 3 and 12 months. Histologic lesion scores were assessed according to the Banff classification. HLA mismatch scores [i.e. eplet, predicted indirectly recognizable HLA-epitopes algorithm (PIRCHE-II), HLA epitope mismatch algorithm (HLA-EMMA), HLA whole antigen A/B/DR] were calculated for all transplant pairs. Formation of dnDSAs was quantified by single antigen beads. RESULTS More than one-third of patients exhibited a progression of chronic lesion scores by at least one Banff grade in tubular atrophy (ct), interstitial fibrosis (ci), arteriolar hyalinosis (ah) and inflammation in the area of interstitial fibrosis and tubular atrophy (i-IFTA) from the 3- to the 12-month biopsy. Multivariable proportional odds logistic regression models revealed no association of HLA mismatch scores with progression of histologic lesions, except for ah and especially HLA-EMMA DRB1 [odds ratio (OR) = 1.10, 95% confidence interval (CI) 1.03-1.18]. Furthermore, the established associations of dnDSA formation with HLA mismatch and MVI (OR = 5.31, 95% CI 1.19-22.57) could be confirmed in our cohort. CONCLUSIONS These data support the association of HLA mismatch and alloimmune response, while suggesting that other factors contribute to early progression of chronic histologic lesions.
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Affiliation(s)
- Rhea Jabbour
- Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Andreas Heinzel
- Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Roman Reindl-Schwaighofer
- Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Mariella G Gregorich
- Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
- Section for Clinical Biometrics, Center for Medical Statistics, Informatics and Intelligent Systems (CeMSIIS), Medical University of Vienna, Vienna, Austria
| | - Heinz Regele
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | | | - Johannes Kläger
- Department of Pathology, Medical University of Vienna, Vienna, Austria
| | - Gottfried Fischer
- Department of Blood Group Serology and Transfusion Medicine, Medical University of Vienna, Vienna, Austria
| | - Alexander Kainz
- Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Jan U Becker
- Institute of Pathology, University Hospital of Cologne, Cologne, Germany
| | - Chris Wiebe
- Department of Medicine, University of Manitoba, Winnipeg, Canada; Shared Health Services Manitoba, Canada; Department of Immunology, University of Manitoba, Winnipeg, Canada
| | - Rainer Oberbauer
- Division of Nephrology and Dialysis, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
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5
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Meneghini M, Tambur AR. HLA (emphasis on DQ) compatibility for longer allograft survival in pediatric transplantation: Modern evidence and challenges. Pediatr Transplant 2024; 28:e14606. [PMID: 37716000 DOI: 10.1111/petr.14606] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 08/08/2023] [Accepted: 08/28/2023] [Indexed: 09/18/2023]
Abstract
Kidney transplantation is the treatment of choice for children with end-stage kidney failure, yet suboptimal outcomes, the need for long-term immunosuppression, and the dependency on consecutive transplants pose significant barriers to success. Providing better HLA-matched organs to pediatric patients seems to be the most logical approach to improve graft and patient outcomes and to reduce risk of anti-HLA sensitization after graft failure. We here review recent literature on HLA matching in pediatric kidney transplantation. We further review newer approaches attempting to improve matching by using molecular mismatch load analysis. Our main focus is on the role of HLA-DQ compatibility between recipient and donor. We further emphasize the need to develop creative approaches that will support HLA (and DQ) matching utilization in organ allocation schemes, at least in those geared specifically for pediatric patients.
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Affiliation(s)
- Maria Meneghini
- Transplant Immunology Laboratory, Feinberg School of Medicine, Comprehensive Transplant Center, Northwestern University, Chicago, Illinois, USA
- Nephrology and Kidney Transplantation Department, Vall d'Hebron University Hospital, Vall d'Hebron Research Institute (VHIR), Barcelona, Spain
| | - Anat Roitberg Tambur
- Transplant Immunology Laboratory, Feinberg School of Medicine, Comprehensive Transplant Center, Northwestern University, Chicago, Illinois, USA
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6
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Kardol-Hoefnagel T, Senejohnny DM, Kamburova EG, Wisse BW, Reteig L, Gruijters ML, Joosten I, Allebes WA, van der Meer A, Hilbrands LB, Baas MC, Spierings E, Hack CE, van Reekum FE, van Zuilen AD, Verhaar MC, Bots ML, Drop ACAD, Plaisier L, Melchers RCA, Seelen MAJ, Sanders JS, Hepkema BG, Lambeck AJA, Bungener LB, Roozendaal C, Tilanus MGJ, Voorter CE, Wieten L, van Duijnhoven EM, Gelens MACJ, Christiaans MHL, van Ittersum FJ, Nurmohamed SA, Lardy NM, Swelsen W, van der Pant KAMI, van der Weerd NC, Ten Berge IJM, Hoitsma A, van der Boog PJM, de Fijter JW, Betjes MGH, Roelen DL, Claas FH, Bemelman FJ, Senev A, Naesens M, Heidt S, Otten HG. Determination of the clinical relevance of donor epitope-specific HLA-antibodies in kidney transplantation. HLA 2024; 103:e15346. [PMID: 38239046 DOI: 10.1111/tan.15346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 12/15/2023] [Accepted: 01/02/2024] [Indexed: 01/23/2024]
Abstract
In kidney transplantation, survival rates are still partly impaired due to the deleterious effects of donor specific HLA antibodies (DSA). However, not all luminex-defined DSA appear to be clinically relevant. Further analysis of DSA recognizing polymorphic amino acid configurations, called eplets or functional epitopes, might improve the discrimination between clinically relevant vs. irrelevant HLA antibodies. To evaluate which donor epitope-specific HLA antibodies (DESAs) are clinically important in kidney graft survival, relevant and irrelevant DESAs were discerned in a Dutch cohort of 4690 patients using Kaplan-Meier analysis and tested in a cox proportional hazard (CPH) model including nonimmunological variables. Pre-transplant DESAs were detected in 439 patients (9.4%). The presence of certain clinically relevant DESAs was significantly associated with increased risk on graft loss in deceased donor transplantations (p < 0.0001). The antibodies recognized six epitopes of HLA Class I, 3 of HLA-DR, and 1 of HLA-DQ, and most antibodies were directed to HLA-B (47%). Fifty-three patients (69.7%) had DESA against one donor epitope (range 1-5). Long-term graft survival rate in patients with clinically relevant DESA was 32%, rendering DESA a superior parameter to classical DSA (60%). In the CPH model, the hazard ratio (95% CI) of clinically relevant DESAs was 2.45 (1.84-3.25) in deceased donation, and 2.22 (1.25-3.95) in living donation. In conclusion, the developed model shows the deleterious effect of clinically relevant DESAs on graft outcome which outperformed traditional DSA-based risk analysis on antigen level.
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Affiliation(s)
- Tineke Kardol-Hoefnagel
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Elena G Kamburova
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Bram W Wisse
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Leon Reteig
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Maartje L Gruijters
- Renal Transplant Unit, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Irma Joosten
- Laboratory Medicine, Laboratory of Medical Immunology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Wil A Allebes
- Laboratory Medicine, Laboratory of Medical Immunology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Arnold van der Meer
- Laboratory Medicine, Laboratory of Medical Immunology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Luuk B Hilbrands
- Department of Nephrology, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands
| | - Marije C Baas
- Department of Nephrology, Radboud University Medical Center, Radboud Institute for Health Sciences, Nijmegen, The Netherlands
| | - Eric Spierings
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
- Central Diagnostic Laboratory (CDL), University Medical Center Utrecht, Utrecht, The Netherlands
| | - Cornelis E Hack
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Franka E van Reekum
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Arjan D van Zuilen
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Marianne C Verhaar
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Michiel L Bots
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | - Adriaan C A D Drop
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Loes Plaisier
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Rowena C A Melchers
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Marc A J Seelen
- Department of Nephrology, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan Stephan Sanders
- Department of Nephrology, University Medical Center Groningen, Groningen, The Netherlands
| | - Bouke G Hepkema
- Department of Laboratory Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - Annechien J A Lambeck
- Department of Laboratory Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - Laura B Bungener
- Department of Laboratory Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - Caroline Roozendaal
- Department of Laboratory Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - Marcel G J Tilanus
- Department of Transplantation Immunology, Tissue Typing Laboratory, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Christina E Voorter
- Department of Transplantation Immunology, Tissue Typing Laboratory, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Lotte Wieten
- Department of Transplantation Immunology, Tissue Typing Laboratory, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Elly M van Duijnhoven
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Mariëlle A C J Gelens
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Maarten H L Christiaans
- Department of Internal Medicine, Division of Nephrology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - Frans J van Ittersum
- Department of Nephrology, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Shaikh A Nurmohamed
- Department of Nephrology, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Neubury M Lardy
- Department of Immunogenetics, Sanquin Diagnostic Services, Amsterdam, The Netherlands
| | - Wendy Swelsen
- Department of Immunogenetics, Sanquin Diagnostic Services, Amsterdam, The Netherlands
| | - Karlijn A M I van der Pant
- Renal Transplant Unit, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Neelke C van der Weerd
- Renal Transplant Unit, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Ineke J M Ten Berge
- Renal Transplant Unit, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Andries Hoitsma
- Dutch Organ Transplant Registry (NOTR), Dutch Transplant Foundation (NTS), Leiden, The Netherlands
| | | | - Johan W de Fijter
- Department of Nephrology, Leiden University Medical Center, Leiden, The Netherlands
| | - Michiel G H Betjes
- Department of Nephrology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Dave L Roelen
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Frans H Claas
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Frederike J Bemelman
- Renal Transplant Unit, Department of Internal Medicine, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Aleksandar Senev
- KU Leuven, Department of Microbiology, Immunology and Transplantation, KU Leuven University, Leuven, Belgium
- Histocompatibility and Immunogenetics Laboratory (HILA), Belgian Red Cross-Flanders, Mechelen, Belgium
| | - Maarten Naesens
- KU Leuven, Department of Microbiology, Immunology and Transplantation, KU Leuven University, Leuven, Belgium
- Department of Nephrology and Renal Transplantation, University Hospitals Leuven, Leuven, Belgium
| | - Sebastiaan Heidt
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Henny G Otten
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, The Netherlands
- Central Diagnostic Laboratory (CDL), University Medical Center Utrecht, Utrecht, The Netherlands
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7
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Kramer CSM, Bezstarosti S, Franke-van Dijk MEI, Vergunst M, Roelen DL, Uyar-Mercankaya M, Voogt-Bakker KH, Heidt S. Antibody verification of HLA class I and class II eplets by human monoclonal HLA antibodies. HLA 2024; 103:e15345. [PMID: 38239050 DOI: 10.1111/tan.15345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 12/11/2023] [Accepted: 12/29/2023] [Indexed: 01/23/2024]
Abstract
In solid organ transplantation, formation of de novo donor-specific HLA antibodies is induced by mismatched eplets on donor HLA molecules. While several studies have shown a strong correlation between the number of eplet mismatches and inferior outcomes, not every eplet mismatch is immunogenic. Eplets are theoretically defined entities, necessitating formal proof that they can be recognised and bound by antibodies. This antibody verification is pivotal to ensure that clinically relevant eplets are considered in studies on molecular matching. Recombinant human HLA-specific monoclonal antibodies (mAbs) were generated from HLA-reactive B cell clones isolated from HLA immunised individuals using recombinant HLA molecules. Subsequently, the reactivity patterns of the mAbs obtained from single antigen bead assay were analysed using HLA-EMMA software to identify single or configurations of solvent accessible amino acids uniquely present on the reactive HLA alleles and were mapped to eplets. Two HLA class I and seven HLA class II-specific human mAbs were generated from four individuals. Extensive mAb reactivity analysis, led to antibody verification of three HLA-DR-specific eplets, and conversion of five eplets (one HLA-A, one HLA-B, two HLA-DR, and one HLA-DP), from provisionally verified to truly antibody-verified. Finally, one HLA-DQ-specific eplet was upgraded from level A2 to level A1 verification evidence. The generation of recombinant human HLA-specific mAbs with different specificities contributes significantly to the antibody verification of eplets and therefore is instrumental for implementation of eplet matching in the clinical setting.
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Affiliation(s)
- Cynthia S M Kramer
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Suzanne Bezstarosti
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
- Department of Nephrology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Manon Vergunst
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Dave L Roelen
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Kim H Voogt-Bakker
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Sebastiaan Heidt
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
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8
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Ho QY, Phang CY, Liew IT, Lai ML, Tien CSY, Thangaraju S, Chan M, Kee T. Unrepresented human leucocyte antigen alleles in single-antigen bead assays: A single-centre cohort study. Int J Immunogenet 2023; 50:306-315. [PMID: 37776087 DOI: 10.1111/iji.12639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 08/25/2023] [Accepted: 09/22/2023] [Indexed: 10/01/2023]
Abstract
Human leucocyte antigen (HLA) alleles may generate antibodies that are undetectable by routine single-antigen beads (SABs) assays if their unique epitopes are unrepresented. We aimed to describe the prevalence and explore the potential impact of unrepresented HLA alleles in standard SAB kits in our cohort. All individuals who had undergone two-field HLA typing (HLA-A/B/C/DRB1/DQA1/-DQB1/-DPA1/-DPB1) from February 2021 to July 2023 were included. Two-field HLA-DRB3/4/5 typing was imputed. Each unrepresented allele was compared with the most similar represented allele in the standard LABScreen, LABScreen ExPlex (One Lambda) and the LIFECODES (Immucor) SAB kits. Differences in eplet expression (HLA Eplet Registry) were identified. Differences in three-dimensional molecular structures were visualized using generated models (SWISS-MODEL). Two-field HLA typing was performed for 116 individuals. Overall, 16.7% of all HLA alleles, found in 36.2% of individuals, were unrepresented by all SAB test kits. Four eplets, found in 12.9% of individuals, were unrepresented in at least 1 SAB kit. Non-Chinese individuals were more likely to have unrepresented HLA alleles and eplets than Chinese individuals. There were differences in HLA allele and eplet representation amongst the different SAB test kits. Use of supplementary SAB test kits may improve HLA allele and eplet representation. Although some HLA alleles were unrepresented, most epitopes were represented in current SAB kits. However, some unrepresented alleles may contain epitopes which may generate undetectable antibodies. Further studies may be needed to investigate the potential clinical impact of these unrepresented alleles and eplets, especially in certain ethnic populations or at-risk individuals.
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Affiliation(s)
- Quan Yao Ho
- Department of Renal Medicine, Singapore General Hospital, Singapore, Singapore
- SingHealth Duke-NUS Transplant Centre, Singapore, Singapore
| | - Chew Yen Phang
- Blood Services Group, Health Sciences Authority, Singapore, Singapore
| | - Ian Tatt Liew
- Department of Renal Medicine, Singapore General Hospital, Singapore, Singapore
- SingHealth Duke-NUS Transplant Centre, Singapore, Singapore
| | - May Ling Lai
- Blood Services Group, Health Sciences Authority, Singapore, Singapore
| | - Carolyn Shan-Yeu Tien
- Department of Renal Medicine, Singapore General Hospital, Singapore, Singapore
- SingHealth Duke-NUS Transplant Centre, Singapore, Singapore
| | - Sobhana Thangaraju
- Department of Renal Medicine, Singapore General Hospital, Singapore, Singapore
- SingHealth Duke-NUS Transplant Centre, Singapore, Singapore
| | - Marieta Chan
- Blood Services Group, Health Sciences Authority, Singapore, Singapore
| | - Terence Kee
- Department of Renal Medicine, Singapore General Hospital, Singapore, Singapore
- SingHealth Duke-NUS Transplant Centre, Singapore, Singapore
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9
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Hug MN, Keller S, Marty T, Gygax D, Meinel D, Spies P, Handschin J, Kleiser M, Vazquez N, Linnik J, Buchli R, Claas F, Heidt S, Kramer CSM, Bezstarosti S, Lee JH, Schaub S, Hönger G. HLA antibody affinity determination: From HLA-specific monoclonal antibodies to donor HLA specific antibodies (DSA) in patient serum. HLA 2023. [PMID: 37191252 DOI: 10.1111/tan.15047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 03/08/2023] [Accepted: 03/20/2023] [Indexed: 05/17/2023]
Abstract
Organs transplanted across donor-specific HLA antibodies (DSA) are associated with a variety of clinical outcomes, including a high risk of acute kidney graft rejection. Unfortunately, the currently available assays to determine DSA characteristics are insufficient to clearly discriminate between potentially harmless and harmful DSA. To further explore the hazard potential of DSA, their concentration and binding strength to their natural target, using soluble HLA, may be informative. There are currently a number of biophysical technologies available that allow the assessment of antibody binding strength. However, these methods require prior knowledge of antibody concentrations. Our objective within this study was to develop a novel approach that combines the determination of DSA-affinity as well as DSA-concentration for patient sample evaluation within one assay. We initially tested the reproducibility of previously reported affinities of human HLA-specific monoclonal antibodies and assessed the technology-specific precision of the obtained results on multiple platforms, including surface plasmon resonance (SPR), bio-layer interferometry (BLI), Luminex (single antigen beads; SAB), and flow-induced dispersion analysis (FIDA). While the first three (solid-phase) technologies revealed comparable high binding-strengths, suggesting measurement of avidity, the latter (in-solution) approach revealed slightly lower binding-strengths, presumably indicating measurement of affinity. We believe that our newly developed in-solution FIDA-assay is particularly suitable to provide useful clinical information by not just measuring DSA-affinities in patient serum samples but simultaneously delivering a particular DSA-concentration. Here, we investigated DSA from 20 pre-transplant patients, all of whom showed negative CDC-crossmatch results with donor cells and SAB signals ranging between 571 and 14899 mean fluorescence intensity (MFI). DSA-concentrations were found in the range between 11.2 and 1223 nM (median 81.1 nM), and their measured affinities fall between 0.055 and 24.7 nM (median 5.34 nM; 449-fold difference). In 13 of 20 sera (65%), DSA accounted for more than 0.1% of total serum antibodies, and 4/20 sera (20%) revealed a proportion of DSA even higher than 1%. To conclude, this study strengthens the presumption that pre-transplant patient DSA consists of various concentrations and different net affinities. Validation of these results in a larger patient cohort with clinical outcomes will be essential in a further step to assess the clinical relevance of DSA-concentration and DSA-affinity.
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Affiliation(s)
- Melanie N Hug
- University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences Muttenz, Muttenz, Switzerland
| | - Sabrina Keller
- University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences Muttenz, Muttenz, Switzerland
| | - Talea Marty
- University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences Muttenz, Muttenz, Switzerland
| | - Daniel Gygax
- University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences Muttenz, Muttenz, Switzerland
| | - Dominik Meinel
- University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences Muttenz, Muttenz, Switzerland
| | - Peter Spies
- University of Applied Sciences and Arts Northwestern Switzerland, School of Life Sciences Muttenz, Muttenz, Switzerland
| | - Joëlle Handschin
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Marc Kleiser
- Department of Laboratory Medicine, University Hospital Basel, Basel, Switzerland
| | - Noemi Vazquez
- Department of Biomedicine, University of Basel, Basel, Switzerland
| | - Janina Linnik
- Department of Biomedicine, University of Basel, Basel, Switzerland
- Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland
- Swiss Institute for Bioinformatics, Basel, Switzerland
| | - Rico Buchli
- Department of Research and Development, PureProtein LLC, Oklahoma City, Oklahoma, USA
| | - Frans Claas
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Sebastiaan Heidt
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Cynthia S M Kramer
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Suzanne Bezstarosti
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jar-How Lee
- Research Department, Terasaki Innovation Center (TIC), Glendale, California, USA
| | - Stefan Schaub
- Department of Biomedicine, University of Basel, Basel, Switzerland
- Department of Laboratory Medicine, University Hospital Basel, Basel, Switzerland
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Gideon Hönger
- Department of Biomedicine, University of Basel, Basel, Switzerland
- Department of Laboratory Medicine, University Hospital Basel, Basel, Switzerland
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10
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Slomp C, Edwards L, Burgess M, Sapir-Pichhadze R, Keown P, Bryan S. Public values and guiding principles for implementing epitope compatibility in kidney transplantation allocation criteria: results from a Canadian online public deliberation. BMC Public Health 2023; 23:844. [PMID: 37165330 PMCID: PMC10170053 DOI: 10.1186/s12889-023-15790-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 04/30/2023] [Indexed: 05/12/2023] Open
Abstract
BACKGROUND Epitope compatibility in deceased donor kidney allocation is an emerging area of precision medicine (PM), seeking to improve compatibility between donor kidneys to transplant candidates in the hope of avoiding kidney rejection. Though the potential benefits of using epitope compatibility are promising, the implied modification of deceased organ allocation criteria requires consideration of significant clinical and ethical trade-offs. As a matter of public policy, these trade-offs should consider public values and preferences. We invited members of the Canadian public to participate in a deliberation about epitope compatibility in deceased donor kidney transplantation; to identify what is important to them and to provide recommendations to policymakers. METHODS An online public deliberation was conducted with members of the Canadian public, in which participants were asked to construct recommendations for policymakers regarding the introduction of epitope compatibility to kidney allocation criteria. In the present paper, a qualitative analysis was conducted to identify the values reflected in participants' recommendations. All virtual sessions were recorded, transcribed, and analyzed using NVivo 12 software. RESULTS Thirty-two participants constructed nine recommendations regarding the adoption of epitope compatibility into deceased donor kidney allocation. Five values were identified that drove participants' recommendations: Health Maximization, Protection/Mitigation of Negative Impacts, Fairness, Science/Evidence-based Healthcare, and Responsibility to Maintain Trust. Conflicts between these values were discussed in terms of operational principles that were required for epitope compatibility to be implemented in an acceptable manner: the needs for Flexibility, Accountability, Transparent Communication and a Transition Plan. All nine recommendations were informed by these four principles. Participant deliberations were often dominated by the conflict between Health Maximization and Fairness or Protection/Mitigation of Negative Impacts, which was discussed as the need for Flexibility. Two additional values (Efficient Use of Resources and Logic/Rationality) were also discussed and were reasons for some participants voting against some recommendations. CONCLUSIONS Public recommendations indicate support for using epitope compatibility in deceased donor kidney allocation. A flexible approach to organ allocation decision-making may allow for the balancing of Health Maximization against maintaining Fairness and Mitigating Negative Impacts. Flexibility is particularly important in the context of epitope compatibility and other PM initiatives where evidence is still emerging.
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Affiliation(s)
- Caitlin Slomp
- BC Children's Hospital Research Institute, 938 W 28th Ave, BC, V5Z 4H4, Vancouver, Canada.
- Department of Psychiatry, University of British Columbia, Vancouver, Canada.
| | - Louisa Edwards
- School of Population & Public Health, University of British Columbia, Vancouver, Canada
- Centre for Clinical Epidemiology and Evaluation, Vancouver Coastal Health Research Institute, Vancouver, Canada
| | - Michael Burgess
- School of Population & Public Health, University of British Columbia, Vancouver, Canada
- W. Maurice Young Centre for Applied Ethics, University of British Columbia, Vancouver, Canada
| | - Ruth Sapir-Pichhadze
- Division of Nephrology, Department of Medicine, McGill University, Montreal, Canada
- Centre for Outcomes Research & Evaluation, Research Institute of the McGill University Health Centre, Montreal, Canada
| | - Paul Keown
- Department of Medicine, University of British Columbia, Vancouver, Canada
- Immune Centre of BC, Vancouver Coastal Health, Vancouver, Canada
| | - Stirling Bryan
- School of Population & Public Health, University of British Columbia, Vancouver, Canada
- Centre for Clinical Epidemiology and Evaluation, Vancouver Coastal Health Research Institute, Vancouver, Canada
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11
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Kleid L, Walter J, Vorstandlechner M, Schneider CP, Michel S, Kneidinger N, Irlbeck M, Wichmann C, Möhnle P, Humpe A, Kauke T, Dick A. Predictive value of molecular matching tools for the development of donor specific HLA-antibodies in patients undergoing lung transplantation. HLA 2023. [PMID: 37068792 DOI: 10.1111/tan.15068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 03/21/2023] [Accepted: 04/06/2023] [Indexed: 04/19/2023]
Abstract
Molecular matching is a new approach for virtual histocompatibility testing in organ transplantation. The aim of our study was to analyze whether the risk for de novo donor-specific HLA antibodies (dnDSA) after lung transplantation (LTX) can be predicted by molecular matching algorithms (MMA) and their combination. In this retrospective study we included 183 patients undergoing LTX at our center from 2012-2020. We monitored dnDSA development for 1 year. Eplet mismatches (epMM) using HLAMatchmaker were calculated and highly immunogenic eplets based on their ElliPro scores were identified. PIRCHE-II scores were calculated using PIRCHE-II algorithm (5- and 11-loci). We compared epMM and PIRCHE-II scores between patients with and without dnDSA using t-test and used ROC-curves to determine optimal cut-off values to categorize patients into four groups. We used logistic regression with AIC to compare the predictive value of PIRCHE-II, epMM, and their combination. In total 28.4% of patients developed dnDSA (n = 52), 12.5% class I dnDSA (n = 23), 24.6% class II dnDSA (n = 45), and 8.7% both class II and II dnDSA (n = 16). Mean epMMs (p-value = 0.005), mean highly immunogenic epMMs (p-value = 0.003), and PIRCHE-II (11-loci) (p = 0.01) were higher in patients with compared to without class II dnDSA. Patients with highly immunogenic epMMs above 30.5 and PIRCHE-II 11-loci above 560.0 were more likely to develop dnDSA (31.1% vs. 14.8%, p-value = 0.03). The logistic regression model including the grouping variable showed the best predictive value. MMA can support clinicians to identify patients at higher or lower risk for developing class II dnDSA and might be helpful tools for immunological risk assessment in LTX patients.
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Affiliation(s)
- Lisa Kleid
- Laboratory for Immunogenetics, Division of Transfusion Medicine, Cell Therapeutics and Haemostaseology, University Hospital, LMU Munich, Munich, Germany
- Division of Transfusion Medicine, Cell Therapeutics and Haemostaseology, University Hospital, LMU Munich, Munich, Germany
| | - Julia Walter
- Division of Thoracic Surgery, University Hospital, LMU Munich, Munich, Germany
- Comprehensive Pneumology Center Munich (CPC-M), German Center for Lung Research (DZL), Munich, Germany
- Department of Medicine V, University Hospital, LMU Munich, Munich, Germany
| | | | - Christian P Schneider
- Division of Thoracic Surgery, University Hospital, LMU Munich, Munich, Germany
- Comprehensive Pneumology Center Munich (CPC-M), German Center for Lung Research (DZL), Munich, Germany
| | - Sebastian Michel
- Comprehensive Pneumology Center Munich (CPC-M), German Center for Lung Research (DZL), Munich, Germany
- Department of Cardiac Surgery, University Hospital, LMU Munich, Munich, Germany
| | - Nikolaus Kneidinger
- Comprehensive Pneumology Center Munich (CPC-M), German Center for Lung Research (DZL), Munich, Germany
- Department of Medicine V, University Hospital, LMU Munich, Munich, Germany
| | - Michael Irlbeck
- Department of Anesthesiology, University Hospital, LMU Munich, Munich, Germany
| | - Christian Wichmann
- Division of Transfusion Medicine, Cell Therapeutics and Haemostaseology, University Hospital, LMU Munich, Munich, Germany
| | - Patrick Möhnle
- Division of Transfusion Medicine, Cell Therapeutics and Haemostaseology, University Hospital, LMU Munich, Munich, Germany
| | - Andreas Humpe
- Division of Transfusion Medicine, Cell Therapeutics and Haemostaseology, University Hospital, LMU Munich, Munich, Germany
| | - Teresa Kauke
- Division of Thoracic Surgery, University Hospital, LMU Munich, Munich, Germany
- Transplantation Center, University Hospital, LMU Munich, Munich, Germany
| | - Andrea Dick
- Laboratory for Immunogenetics, Division of Transfusion Medicine, Cell Therapeutics and Haemostaseology, University Hospital, LMU Munich, Munich, Germany
- Division of Transfusion Medicine, Cell Therapeutics and Haemostaseology, University Hospital, LMU Munich, Munich, Germany
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12
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Tambur AR, Das R. Can We Use Eplets (or Molecular) Mismatch Load Analysis to Improve Organ Allocation? The Hope and the Hype. Transplantation 2023; 107:605-615. [PMID: 36163639 PMCID: PMC9944744 DOI: 10.1097/tp.0000000000004307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 06/14/2022] [Accepted: 07/03/2022] [Indexed: 11/25/2022]
Abstract
In recent years, there have been calls for implementation of "epitope matching" in deceased-donor organ allocation policies (later changed to "eplet matching"). Emerging data indeed support the use of molecular mismatch load analysis in specific patient groups, with the objective of posttransplant stratification into different treatment arms. For this purpose, the expectation is to statistically categorize patients as low- or high-immune-risk. Importantly, these patients will continue to be monitored' and their risk category, as well as their management, can be adjusted according to on-going findings. However, when discussing deceased donor organ allocation and matching algorithms, where the decision is not modifiable and has lasting impact on outcomes, the situation is fundamentally different. The goal of changing allocation schemes is to achieve the best possible HLA compatibility between donor and recipient. Immunologically speaking, this is a very different objective. For this purpose, the specific interplay of immunogenicity between the donor and any potential recipient must be understood. In seeking compatibility, the aim is not to redefine matching but to identify those mismatches that are "permissible" or' in other words, less immunogenic. In our eagerness to improve transplant outcome, unfortunately, we have conflated the hype with the hope. Terminology is used improperly, and new terms are created in the process with no sufficient support. Here, we call for a cautious evaluation of baseline assumptions and a critical review of the evidence to minimize unintended consequences.
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Affiliation(s)
- Anat R. Tambur
- Comprehensive Transplant Center, Department of Surgery, Northwestern University, Chicago, IL
| | - Rajdeep Das
- Comprehensive Transplant Center, Department of Surgery, Northwestern University, Chicago, IL
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13
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Meng T, Bezstarosti S, Singh U, Yap M, Scott L, Petrosyan N, Quiroz F, Eps NV, Hui EKW, Suh D, Zhu Q, Pei R, Kramer CSM, Claas FHJ, Lowe D, Heidt S. Site-directed mutagenesis of HLA molecules reveals the functional epitope of a human HLA-A1/A36-specific monoclonal antibody. HLA 2023; 101:138-142. [PMID: 36401817 PMCID: PMC10099858 DOI: 10.1111/tan.14895] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 10/13/2022] [Accepted: 11/18/2022] [Indexed: 11/21/2022]
Abstract
Eplet 44KM is currently listed in the HLA Epitope Registry but does not adhere to the eplet definition of an amino acid configuration within a 3.5 Å radius. Eplet 44KM has been previously redefined to the antibody-verified reactivity pattern 44K/150V/158V, based on reactivity analysis of monoclonal antibody VDK1D12. Since the three residues are always simultaneously present on common HLA alleles, methods to define which residue is crucial for antibody-induction and binding are limited. In this proof-of-concept study, we performed site-directed mutagenesis to narrow down the antibody-verified reactivity pattern 44K/150V/158V to a single amino acid and defined 44K as the eplet or functional epitope of mAb VDK1D12.
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Affiliation(s)
- Tina Meng
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Suzanne Bezstarosti
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands.,Department of Internal Medicine (Nephrology), Leiden University Medical Center, Leiden, The Netherlands
| | - Ujjwala Singh
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Michelle Yap
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Laura Scott
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Naiiry Petrosyan
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Fred Quiroz
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Ned Van Eps
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Eric Ka-Wai Hui
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - David Suh
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Quansheng Zhu
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Rui Pei
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Cynthia S M Kramer
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - Frans H J Claas
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
| | - David Lowe
- Department of Research and Development, One Lambda, Inc. (A Part of Thermo Fisher Scientific Inc.), West Hills, California, USA
| | - Sebastiaan Heidt
- Department of Immunology, Leiden University Medical Center, Leiden, The Netherlands
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14
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Kaljanac M, Abken H. Do Treg Speed Up with CARs? Chimeric Antigen Receptor Treg Engineered to Induce Transplant Tolerance. Transplantation 2023; 107:74-85. [PMID: 36226849 PMCID: PMC9746345 DOI: 10.1097/tp.0000000000004316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 06/13/2022] [Accepted: 06/21/2022] [Indexed: 02/07/2023]
Abstract
Adoptive transfer of regulatory T cells (Treg) can induce transplant tolerance in preclinical models by suppressing alloantigen-directed inflammatory responses; clinical translation was so far hampered by the low abundance of Treg with allo-specificity in the peripheral blood. In this situation, ex vivo engineering of Treg with a T-cell receptor (TCR) or chimeric antigen receptor (CAR) provides a cell population with predefined specificity that can be amplified and administered to the patient. In contrast to TCR-engineered Treg, CAR Treg can be redirected toward a broad panel of targets in an HLA-unrestricted fashion' making these cells attractive to provide antigen-specific tolerance toward the transplanted organ. In preclinical models, CAR Treg accumulate and amplify at the targeted transplant, maintain their differentiated phenotype, and execute immune repression more vigorously than polyclonal Treg. With that, CAR Treg are providing hope in establishing allospecific, localized immune tolerance in the long term' and the first clinical trials administering CAR Treg for the treatment of transplant rejection are initiated. Here, we review the current platforms for developing and manufacturing alloantigen-specific CAR Treg and discuss the therapeutic potential and current hurdles in translating CAR Treg into clinical exploration.
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Affiliation(s)
- Marcell Kaljanac
- Division Genetic Immunotherapy, and Chair Genetic Immunotherapy, Leibniz Institute for Immunotherapy, University Regensburg, Regensburg, Germany
| | - Hinrich Abken
- Division Genetic Immunotherapy, and Chair Genetic Immunotherapy, Leibniz Institute for Immunotherapy, University Regensburg, Regensburg, Germany
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15
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Impact of Sensitization on Waiting Time Prior to Kidney Transplantation in Germany. Transplantation 2022; 106:2448-2455. [PMID: 35973058 DOI: 10.1097/tp.0000000000004238] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Assignment of unacceptable HLA mismatches (UAMs) prevents transplantation of incompatible grafts but potentially prolongs waiting time. Whether this is true in the Eurotransplant Kidney Allocation System (ETKAS) and the Eurotransplant Senior Program in Germany is highly debated and relevant for UAM policies. METHODS Donor pool restriction due to UAM was expressed as percent virtual panel-reactive antibodies (vPRAs). Kaplan-Meier estimates and multivariable Cox regression models were used to analyze the impact of vPRA levels on waiting time and transplant probability during a period of 2 y in all patients eligible for a kidney graft unter standard circumstances in Germany on February 1, 2019 (n = 6533). Utility of the mismatch probability score to compensate for sensitization in ETKAS was also investigated. RESULTS In ETKAS, donor pool restriction resulted in significant prolongation of waiting time and reduction in transplant probability only in patients with vPRA levels above 85%. This was most evident in patients with vPRA levels above 95%, whereas patients in the acceptable mismatch program had significantly shorter waiting times and higher chances for transplantation than nonsensitized patients. In the Eurotransplant Senior Program, vPRA levels above 50% resulted in significantly longer waiting times and markedly reduced the chance for transplantation. Compensation for sensitization by the mismatch probability score was insufficient. CONCLUSIONS Donor pool restriction had no significant impact on waiting time in most sensitized patients. However, despite the existence of the acceptable mismatch program, the majority of highly sensitized patients is currently disadvantaged and would benefit from better compensation mechanisms.
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16
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Gál P, Brábek J, Holub M, Jakubek M, Šedo A, Lacina L, Strnadová K, Dubový P, Hornychová H, Ryška A, Smetana K. Autoimmunity, cancer and COVID-19 abnormally activate wound healing pathways: critical role of inflammation. Histochem Cell Biol 2022; 158:415-434. [PMID: 35867145 PMCID: PMC9305064 DOI: 10.1007/s00418-022-02140-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/06/2022] [Indexed: 11/30/2022]
Abstract
Recent evidence indicates that targeting IL-6 provides broad therapeutic approaches to several diseases. In patients with cancer, autoimmune diseases, severe respiratory infections [e.g. coronavirus disease 2019 (COVID-19)] and wound healing, IL-6 plays a critical role in modulating the systemic and local microenvironment. Elevated serum levels of IL-6 interfere with the systemic immune response and are associated with disease progression and prognosis. As already noted, monoclonal antibodies blocking either IL-6 or binding of IL-6 to receptors have been used/tested successfully in the treatment of rheumatoid arthritis, many cancer types, and COVID-19. Therefore, in the present review, we compare the impact of IL-6 and anti-IL-6 therapy to demonstrate common (pathological) features of the studied diseases such as formation of granulation tissue with the presence of myofibroblasts and deposition of new extracellular matrix. We also discuss abnormal activation of other wound-healing-related pathways that have been implicated in autoimmune disorders, cancer or COVID-19.
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Affiliation(s)
- Peter Gál
- Department of Pharmacology, Pavol Jozef Šafárik University, Košice, Slovak Republic
- Department of Biomedical Research, East-Slovak Institute of Cardiovascular Diseases, Košice, Slovak Republic
- Prague Burn Centre, Third Faculty of Medicine, Charles University and University Hospital Kralovske Vinohrady, Prague, Czech Republic
| | - Jan Brábek
- Department of Cell Biology, Faculty of Science, Charles University, 120 00 Prague 2, Czech Republic
- BIOCEV, Faculty of Science, Charles University, 252 50 Vestec, Czech Republic
| | - Michal Holub
- Department of Infectious Diseases, First Faculty of Medicine, Military University Hospital Prague and Charles University, 160 00 Prague, Czech Republic
| | - Milan Jakubek
- Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University, 120 00 Prague 2, Czech Republic
- BIOCEV, First Faculty of Medicine, Charles University, 252 50 Vestec, Czech Republic
- Department of Analytical Chemistry, University of Chemistry and Technology Prague, 166 28 Prague 6, Czech Republic
| | - Aleksi Šedo
- Institute of Biochemistry and Experimental Oncology, First Faculty of Medicine, Charles University, 120 00 Praha 2, Czech Republic
| | - Lukáš Lacina
- BIOCEV, First Faculty of Medicine, Charles University, 252 50 Vestec, Czech Republic
- Institute of Anatomy, First Faculty of Medicine, Charles University, 120 00 Prague 2, Czech Republic
- Department of Dermatovenereology, First Faculty of Medicine, Charles University, 120 00 Prague 2, Czech Republic
| | - Karolína Strnadová
- BIOCEV, First Faculty of Medicine, Charles University, 252 50 Vestec, Czech Republic
- Institute of Anatomy, First Faculty of Medicine, Charles University, 120 00 Prague 2, Czech Republic
| | - Petr Dubový
- Institute of Anatomy, Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic
| | - Helena Hornychová
- The Fingerland Department of Pathology, Faculty of Medicine Hradec Králové, Charles University, 500 05 Hradec Králové, Czech Republic
| | - Aleš Ryška
- The Fingerland Department of Pathology, Faculty of Medicine Hradec Králové, Charles University, 500 05 Hradec Králové, Czech Republic
| | - Karel Smetana
- BIOCEV, First Faculty of Medicine, Charles University, 252 50 Vestec, Czech Republic
- Institute of Anatomy, First Faculty of Medicine, Charles University, 120 00 Prague 2, Czech Republic
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17
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Niemann M, Strehler Y, Lachmann N, Halleck F, Budde K, Hönger G, Schaub S, Matern BM, Spierings E. Snowflake epitope matching correlates with child-specific antibodies during pregnancy and donor-specific antibodies after kidney transplantation. Front Immunol 2022; 13:1005601. [PMID: 36389845 PMCID: PMC9649433 DOI: 10.3389/fimmu.2022.1005601] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Accepted: 09/26/2022] [Indexed: 10/01/2023] Open
Abstract
Development of donor-specific human leukocyte antigen (HLA) antibodies (DSA) remains a major risk factor for graft loss following organ transplantation, where DSA are directed towards patches on the three-dimensional structure of the respective organ donor's HLA proteins. Matching donors and recipients based on HLA epitopes appears beneficial for the avoidance of DSA. Defining surface epitopes however remains challenging and the concepts underlying their characterization are not fully understood. Based on our recently implemented computational deep learning pipeline to define HLA Class I protein-specific surface residues, we hypothesized a correlation between the number of HLA protein-specific solvent-accessible interlocus amino acid mismatches (arbitrarily called Snowflake) and the incidence of DSA. To validate our hypothesis, we considered two cohorts simultaneously. The kidney transplant cohort (KTC) considers 305 kidney-transplanted patients without DSA prior to transplantation. During the follow-up, HLA antibody screening was performed regularly to identify DSA. The pregnancy cohort (PC) considers 231 women without major sensitization events prior to pregnancy who gave live birth. Post-delivery serum was screened for HLA antibodies directed against the child's inherited paternal haplotype (CSA). Based on the involved individuals' HLA typings, the numbers of interlocus-mismatched antibody-verified eplets (AbvEPS), the T cell epitope PIRCHE-II model and Snowflake were calculated locus-specific (HLA-A, -B and -C), normalized and pooled. In both cohorts, Snowflake numbers were significantly elevated in recipients/mothers that developed DSA/CSA. Univariable regression revealed significant positive correlation between DSA/CSA and AbvEPS, PIRCHE-II and Snowflake. Snowflake numbers showed stronger correlation with numbers of AbvEPS compared to Snowflake numbers with PIRCHE-II. Our data shows correlation between Snowflake scores and the incidence of DSA after allo-immunization. Given both AbvEPS and Snowflake are B cell epitope models, their stronger correlation compared to PIRCHE-II and Snowflake appears plausible. Our data confirms that exploring solvent accessibility is a valuable approach for refining B cell epitope definitions.
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Affiliation(s)
| | - Yara Strehler
- Center for Tumor Medicine, H&I Laboratory, Charité University Medicine Berlin, Berlin, Germany
| | - Nils Lachmann
- Center for Tumor Medicine, H&I Laboratory, Charité University Medicine Berlin, Berlin, Germany
| | - Fabian Halleck
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Klemens Budde
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Gideon Hönger
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
- Transplantation Immunology, Department of Biomedicine, University of Basel, Basel, Switzerland
- HLA-Diagnostics and Immunogenetics, Department of Laboratory Medicine, University Hospital Basel, Basel, Switzerland
| | - Stefan Schaub
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
- Transplantation Immunology, Department of Biomedicine, University of Basel, Basel, Switzerland
- HLA-Diagnostics and Immunogenetics, Department of Laboratory Medicine, University Hospital Basel, Basel, Switzerland
| | - Benedict M. Matern
- Center for Translational Immunology, University Medical Center, Utrecht, Netherlands
| | - Eric Spierings
- Center for Translational Immunology, University Medical Center, Utrecht, Netherlands
- Central Diagnostic Laboratory, University Medical Center, Utrecht, Netherlands
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Niemann M, Matern BM, Spierings E. Snowflake: A deep learning-based human leukocyte antigen matching algorithm considering allele-specific surface accessibility. Front Immunol 2022; 13:937587. [PMID: 35967374 PMCID: PMC9372366 DOI: 10.3389/fimmu.2022.937587] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/11/2022] [Indexed: 12/12/2022] Open
Abstract
Histocompatibility in solid-organ transplantation has a strong impact on long-term graft survival. Although recent advances in matching of both B-cell epitopes and T-cell epitopes have improved understanding of allorecognition, the immunogenic determinants are still not fully understood. We hypothesized that HLA solvent accessibility is allele-specific, thus supporting refinement of HLA B-cell epitope prediction. We developed a computational pipeline named Snowflake to calculate solvent accessibility of HLA Class I proteins for deposited HLA crystal structures, supplemented by constructed HLA structures through the AlphaFold protein folding predictor and peptide binding predictions of the APE-Gen docking framework. This dataset trained a four-layer long short-term memory bidirectional recurrent neural network, which in turn inferred solvent accessibility of all known HLA Class I proteins. We extracted 676 HLA Class-I experimental structures from the Protein Data Bank and supplemented it by 37 Class-I alleles for which structures were predicted. For each of the predicted structures, 10 known binding peptides as reported by the Immune Epitope DataBase were rendered into the binding groove. Although HLA Class I proteins predominantly are folded similarly, we found higher variation in root mean square difference of solvent accessibility between experimental structures of different HLAs compared to structures with identical amino acid sequence, suggesting HLA’s solvent accessible surface is protein specific. Hence, residues may be surface-accessible on e.g. HLA-A*02:01, but not on HLA-A*01:01. Mapping these data to antibody-verified epitopes as defined by the HLA Epitope Registry reveals patterns of (1) consistently accessible residues, (2) only subsets of an epitope’s residues being consistently accessible and (3) varying surface accessibility of residues of epitopes. Our data suggest B-cell epitope definitions can be refined by considering allele-specific solvent-accessibility, rather than aggregating HLA protein surface maps by HLA class or locus. To support studies on epitope analyses in organ transplantation, the calculation of donor-allele-specific solvent-accessible amino acid mismatches was implemented as a cloud-based web service.
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Affiliation(s)
- Matthias Niemann
- Research and Development, PIRCHE AG, Berlin, Germany
- *Correspondence: Matthias Niemann,
| | - Benedict M. Matern
- Center for Translational Immunology, University Medical Center, Utrecht, Netherlands
| | - Eric Spierings
- Center for Translational Immunology, University Medical Center, Utrecht, Netherlands
- Central Diagnostic Laboratory, University Medical Center, Utrecht, Netherlands
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19
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Gille I, Claas FHJ, Haasnoot GW, Heemskerk MHM, Heidt S. Chimeric Antigen Receptor (CAR) Regulatory T-Cells in Solid Organ Transplantation. Front Immunol 2022; 13:874157. [PMID: 35720402 PMCID: PMC9204347 DOI: 10.3389/fimmu.2022.874157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 04/01/2022] [Indexed: 11/13/2022] Open
Abstract
Solid organ transplantation is the treatment of choice for various end-stage diseases, but requires the continuous need for immunosuppression to prevent allograft rejection. This comes with serious side effects including increased infection rates and development of malignancies. Thus, there is a clinical need to promote transplantation tolerance to prevent organ rejection with minimal or no immunosuppressive treatment. Polyclonal regulatory T-cells (Tregs) are a potential tool to induce transplantation tolerance, but lack specificity and therefore require administration of high doses. Redirecting Tregs towards mismatched donor HLA molecules by modifying these cells with chimeric antigen receptors (CAR) would render Tregs far more effective at preventing allograft rejection. Several studies on HLA-A2 specific CAR Tregs have demonstrated that these cells are highly antigen-specific and show a superior homing capacity to HLA-A2+ allografts compared to polyclonal Tregs. HLA-A2 CAR Tregs have been shown to prolong survival of HLA-A2+ allografts in several pre-clinical humanized mouse models. Although promising, concerns about safety and stability need to be addressed. In this review the current research, obstacles of CAR Treg therapy, and its potential future in solid organ transplantation will be discussed.
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Affiliation(s)
- Ilse Gille
- Department of Immunology, Leiden University Medical Center, Leiden, Netherlands.,Department of Hematology, Leiden University Medical Center, Leiden, Netherlands
| | - Frans H J Claas
- Department of Immunology, Leiden University Medical Center, Leiden, Netherlands.,Eurotransplant Reference Laboratory, Leiden University Medical Center, Leiden, Netherlands
| | - Geert W Haasnoot
- Department of Immunology, Leiden University Medical Center, Leiden, Netherlands.,Eurotransplant Reference Laboratory, Leiden University Medical Center, Leiden, Netherlands
| | | | - Sebastiaan Heidt
- Department of Immunology, Leiden University Medical Center, Leiden, Netherlands.,Eurotransplant Reference Laboratory, Leiden University Medical Center, Leiden, Netherlands
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