Time filter

Source Type

Leiden, Netherlands

Horan J.,Emory University | Wang T.,Medical College of Wisconsin | Haagenson M.,Center for International Blood and Marrow Transplant Research | Spellman S.R.,Center for International Blood and Marrow Transplant Research | And 12 more authors.

The importance of human leukocyte antigen (HLA) matching in unrelated donor transplantation for nonmalignant diseases (NMD) has yet to be defined. We analyzed data from 663 unrelated marrow and peripheral blood stem cell transplants performed from 1995 to 2007 for treatment of NMD. Transplantation from a donor mismatched at the HLA-A, -B, -C, or -DRB1, but not -DQB1 or -DPB1, loci was associated with higher mortality in multivariate analyses (P = .002). The hazard ratio for mortality for single (7/8) and double mismatched (6/8) transplants was 1.29 (0.97-1.72; P = .079) and 1.82 (1.30- 2.55; P = .0004), respectively, compared with 8/8 matched transplants. HLA mismatches were not associated with acute or chronic GVHD, but were strongly associated with graft failure. After adjustment for other factors, the odds ratio for graft failure for 7/8 and 6/8 (allele and/or antigen) matched pairs compared with 8/8 matched transplants was 2.81 (1.74-4.54; P < .0001) and 2.22 (1.26-3.97; P = .006), respectively. Patients with NMD should receive transplants from allele matched (8/8) donors if possible. Unlike the case with malignancies, HLAmismatching inNMDis associated with graft failure rather than GVHD. © 2012 by The American Society of Hematology. Source

van Halteren A.G.,Immunology Laboratory | Netelenbos T.,Leiden University | Fechter M.,Europdonor Foundation

Allogeneic hematopoietic stem cell transplantation (HSCT) is a widely applied treatment for disorders mainly involving the hematopoietic system. The success of this treatment depends on many different patient- and donor-specific factors. Based on higher CD34+ yields and superior clinical outcomes associated with the use of male donors, males are generally seen as the preferred HSCT donor. In addition, female donors are notorious for bearing memory type lymphocytes induced by previous pregnancies; such alloimmune cells may provoke unwanted immune reactions such as graft-vs.-host disease in transplant recipients. Consequently, many transplant centers try to avoid parous donors, particularly when searching the best unrelated donor for a male patient. We recently showed that parous women with female offspring have an anti-male directed tolerogenic immune status comparable to that of nulliparous donors. As discussed in this article addendum, the sex of the donor's offspring combined with the presence of HY-specific T regulator cells are possibly better selection criteria than parity status per se. Source

Boo M.,National Marrow Donor Program | Van Walraven S.M.,Europdonor Foundation | Chapman J.,University of Sydney | Lindberg B.,National Marrow Donor Program | And 5 more authors.

Hematopoietic stem cell transplantation is a curative procedure for life-threatening hematologic diseases. Donation of hematopoietic stem cells (HSCs) from an unrelated donor, frequently residing in another country, may be the only option for 70% of those in need of unrelated hematopoietic stem cell transplantation. To maximize the opportunity to find the best available donor, individual donor registries collaborate internationally. To provide homogeneity of practice among registries, the World Marrow Donor Association (WMDA) sets standards against which registries are accredited and provides guidance and regulations about unrelated donor safety and care. A basic tenet of the donor registries is that unrelated HSC donation is an altruistic act; nonpayment of donors is entrenched in the WMDA standards and in international practice. In the United States, the prohibition against remuneration of donors has recently been challenged. Here, we describe the reasons that the WMDA continues to believe that HSC donors should not be paid because of ethical concerns raised by remuneration, potential to damage the public will to act altruistically, the potential for coercion and exploitation of donors, increased risk to patients, harm to local transplantation programs and international stem cell exchange, and the possibility of benefiting some patients while disadvantaging others. © 2011 by The American Society of Hematology. Source

Brand A.,Europdonor Foundation | Brand A.,Leiden University | Doxiadis I.N.,Leiden University | Roelen D.L.,Leiden University
Tissue Antigens

While the role of donor-specific antibodies (DSA) in solid organ transplantation is well established, their importance in hematopoietic stem cell transplantation (HSCT) is only now becoming clear. A review of the literature reporting on HLA immunization in HSCT provides ample circumstantial evidence that donor-specific HLA antibodies (DSA) are associated with a 2- to 10-fold increase of graft failure of HLA mismatched HSCT, irrespective the type of the graft, or the patient conditioning. Nevertheless, this is not a condition 'sine qua non', and engraftment has been documented despite the presence of DSA. However, prediction of graft failure based on serology is cumbersome. Although sensitivity and specificity of current solid-phase assays (SPAs) for HLA antibody detection are high, correlation with graft failure remains elusive. When lacking an alternative donor, reduction of strong reacting DSA must be attempted. Unfortunately, results of DSA reduction treatments in HSCT are scarcely reported. Case reports show that persisting DSA after plasma-exchange and immunosuppressive treatment can become negative after a 'last rescue' in vivo absorption with antigen-bearing platelets or donor lymphocyte transfusions. The destruction of engrafting hematopoietic cells by antibodies appears to be an immediate event. Blocking antibody mediated effector functions, e.g. with intravenous immunoglobulin (IvIg), may have additional value, despite IvIg often not reducing the antibody titre. An even less explored aspect of HLA-immunization is the presence of non-DSA antibodies in the host or HLA antibodies emerging post-transplantation. Such antibodies, either causally or as confounders, may be associated with negative transplant outcome. We conclude that HLA antibody assessment should be at the forefront in the treatment handbook of HSCT. © 2012 John Wiley & Sons A/S. Source

Fleischhauer K.,Unit of Molecular and Functional Immunogenetics | Shaw B.E.,The Institute of Cancer Research | Shaw B.E.,Anthony Nolan Research Institute | Gooley T.,Fred Hutchinson Cancer Research Center | And 14 more authors.
The Lancet Oncology

Background: The risks after unrelated-donor haemopoietic-cell transplantation with matched HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1 alleles between donor and recipient (10/10 matched) can be decreased by selection of unrelated donors who also match for HLA-DPB1; however, such donors are difficult to find. Classification of HLA-DPB1 mismatches based on T-cell-epitope groups could identify mismatches that might be tolerated (permissive) and those that would increase risks (non-permissive) after transplantation. We did a retrospective study to compare outcomes between permissive and non-permissive HLA-DPB1 mismatches in unrelated-donor haemopoietic-cell transplantation. Methods: HLA and clinical data for related-donor transplantations submitted to the International Histocompatibility Working Group in haemopoietic-cell transplantation were analysed retrospectively. HLA-DPB1 T-cell-epitope groups were assigned according to a functional algorithm based on alloreactive T-cell crossreactivity patterns. Recipients and unrelated donors matching status were classified as HLA-DPB1 match, non-permissive HLA-DPB1 mismatch (those with mismatched T-cell-epitope groups), or permissive HLA-DPB1 mismatch (those with matched T-cell-epitope groups). The clinical outcomes assessed were overall mortality, non-relapse mortality, relapse, and severe (grade 3-4) acute graft-versus-host disease (aGvHD). Findings: Of 8539 transplantations, 5428 (64%) were matched for ten of ten HLA alleles (HLA 10/10 matched) and 3111 (36%) for nine of ten alleles (HLA 9/10 matched). Of the group overall, 1719 (20%) were HLA-DPB1 matches, 2670 (31%) non-permissive HLA-DPB1 mismatches, and 4150 (49%) permissive HLA-DPB1 mismatches. In HLA 10/10-matched transplantations, non-permissive mismatches were associated with a significantly increased risk of overall mortality (hazard ratio [HR] 1·15, 95% CI 1·05-1·25; p=0·002), non-relapse mortality (1·28, 1·14-1·42; p<0·0001), and severe aGvHD (odds ratio [OR] 1·31, 95% CI 1·11-1·54; p=0·001), but not relapse (HR 0·89, 95% CI 0·77-1·02; p=0·10), compared with permissive mismatches. There were significant differences between permissive HLA-DPB1 mismatches and HLA-DPB1 matches in terms of non-relapse mortality (0·86, 0·75-0·98; p=0·03) and relapse (1·34, 1·17-1·54; p<0·0001), but not for overall mortality (0·96, 0·87-1·06; p=0·40) or aGvHD (OR 0·84, 95% CI 0·69-1·03; p=0·09). In the HLA 9/10 matched population, non-permissive HLA-DPB1 mismatches also increased the risk of overall mortality (HR 1·10, 95% CI 1·00-1·22; p=0·06), non-relapse mortality (1·19, 1·05-1·36; p=0·007), and severe aGvHD (OR 1·37, 95% CI 1·13-1·66; p=0·002) compared with permissive mismatches, but the risk of relapse was the same in both groups (HR 0·93, 95% CI 0·78-1·11; p=0·44). Outcomes for HLA 10/10-matched transplantations with non-permissive HLA-DPB1 mismatches did not differ substantially from those for HLA 9/10-matched transplantations with permissive HLA-DPB1 mismatches or HLA-DPB1 matches. Interpretation: T-cell-epitope matching defines permissive and non-permissive HLA-DPB1 mismatches. Avoidance of an unrelated donor with a non-permissive T-cell-epitope mismatch at HLA-DPB1 might provide a practical clinical strategy for lowering the risks of mortality after unrelated-donor haemopoietic-cell transplantation. Funding: National Institutes of Health; Associazione Italiana per la Ricerca sul Cancro; Telethon Foundation; Italian Ministry of Health; Cariplo Foundation; National Cancer Institute; National Heart, Lung and Blood Institute; National Institute of Allergy and Infectious Diseases; Office of Naval Research; IRGHET Paris; Swedish Cancer Society; Children's Cancer Foundation; Swedish Research Council; Cancer Society in Stockholm; Karolinska Institutet; and Leukemia and Lymphoma Society. © 2012 Elsevier Ltd. Source

Discover hidden collaborations