The National Marrow Donor Program (NMDP) operates the Be The Match Registry to serve patients who require an allogeneic hematopoietic cell transplant (alloHCT). The factors that result in progression of an active donor search (ie, request for tissue typing or stem cell donation) to alloHCT are poorly understood. Some factors, such as differences in access by ethnic group, are known; however, deeper understanding of other patient and search factors is needed.
View Article and Find Full Text PDFHLA allele matching is critical to successful bone marrow transplantation between a patient and donor. Non-functional HLA alleles, so called 'null alleles', are not well described within a large population of well HLA-typed ethnically diverse individuals despite their impact on donor selection. A retrospective analysis was performed on 833,789 unrelated donors (URDs) in the National Marrow Donor Program's Be The Match Registry® typed for HLA-A, -B, -C, -DRB1, -DQB1, and -DPB1 by next-generation DNA sequencing.
View Article and Find Full Text PDFA catalog of common, intermediate and well-documented (CIWD) HLA-A, -B, -C, -DRB1, -DRB3, -DRB4, -DRB5, -DQB1 and -DPB1 alleles has been compiled from over 8 million individuals using data from 20 unrelated hematopoietic stem cell volunteer donor registries. Individuals are divided into seven geographic/ancestral/ethnic groups and data are summarized for each group and for the total population. P (two-field) and G group assignments are divided into one of four frequency categories: common (≥1 in 10 000), intermediate (≥1 in 100 000), well-documented (≥5 occurrences) or not-CIWD.
View Article and Find Full Text PDFTo characterize donor search and selection practices, the National Marrow Donor Program (NMDP) Histocompatibility Advisory Group developed a survey of allogeneic hematopoietic cell transplant (HCT) physicians and search coordinators. The objectives were to describe search practices, understand practices surrounding urgent time to HCT, and characterize strategies used when identifying a matched unrelated donor is unlikely. Participants included US physician members of the American Society for Transplantation and Cellular Therapy and donor search coordinators within the NMDP network.
View Article and Find Full Text PDFAllogeneic hematopoietic cell transplantation involves consideration of both donor and recipient characteristics to guide the selection of a suitable graft. Sufficient high-resolution donor-recipient HLA match is of primary importance in transplantation with adult unrelated donors, using conventional graft-versus-host disease prophylaxis. In cord blood transplantation, optimal unit selection requires consideration of unit quality, cell dose and HLA-match.
View Article and Find Full Text PDFCD34 cell dose is critical for cord blood (CB) engraftment. However, the CD34 content of the CB inventory in the United States is unknown. We examined the CD34 cell content of 126 341 red blood cell-depleted US units banked from January 2007 to September 2017 with a total nucleated cell (TNC) count of ≥90 × 10 and a cryovolume of 24-55 mL.
View Article and Find Full Text PDFDonor factors, in addition to HLA matching status, have been associated with recipient survival in unrelated donor (URD) hematopoietic cell transplantation (HCT); however, there is no hierarchical algorithm that weights the characteristics of individual donors against each other in a quantitative manner to facilitate donor selection. The goal of this study was to develop and validate a donor selection score that prioritizes donor characteristics associated with better survival in 8/8 HLA-matched URDs. Two separate patient/donor cohorts, the first receiving HCT between 1999 and 2011 (n = 5952, c1), and the second between 2012 and 2014 (n = 4510, c2) were included in the analysis.
View Article and Find Full Text PDFBackground: Umbilical cord blood units provide an important stem cell source for transplantation, particularly for patients of ethnic diversity who may not have suitably matched available, adult-unrelated donors. However, with the cost of cord blood unit acquisition from public banks significantly higher than that for adult-unrelated donors, attention is focused on decreasing cost yet still providing cord blood units to patients in need. Historical practices of banking units with low total nucleated cell counts, including units with approximately 90 × 10 total nucleated cells, indicates that most banked cord blood units have much lower total nucleated cell counts than are required for transplant.
View Article and Find Full Text PDFThe effects of inter-unit HLA-match on early outcomes with regards to double cord blood transplantation have not been established. Therefore, we studied the effect of inter-unit HLA-mismatching on the outcomes of 449 patients with acute leukemia after double cord blood transplantation. Patients were divided into two groups: one group that included transplantations with inter-unit mismatch at 2 or less HLA-loci (n=381) and the other group with inter-unit mismatch at 3 or 4 HLA-loci (n=68).
View Article and Find Full Text PDFBackground: Despite over 6 million subjects contributing to the National Marrow Donor Program human leukocyte antigen (HLA) haplotype frequency reference data (HFD), haplotypes cannot be predicted from the HLA assignments of some patients searching for an unrelated donor (URD) in the Be The Match Registry®. We aimed to determine the incidence of these patient searches and whether haplotypes lacking from the HFD can be found among the low-resolution typed URD pool.
Materials And Methods: New NMDP searches with uncommon patient haplotypes (UPH), defined as a lack of haplotype pairs in any single ethnic group in the HFD based upon HLA-A˜C˜B˜DRB1˜DQB1, were identified.
Biol Blood Marrow Transplant
January 2017
HLA-DPB1 permissive matching based on T cell epitope (TCE) groups should be considered when selecting among equally matched HLA-A, -B, -C, -DRB1 unrelated hematopoietic stem cell donors to improve patient survival. Previous studies have defined 3 TCE groups based on functional assays of alloreactivity. Combinations of donor and recipient DPB1 alleles with low immunogenic potential identify permissive donors, who provide no increased risk of mortality compared with DPB1-matched donors.
View Article and Find Full Text PDFBone Marrow Transplant
November 2016
A simple scoring system that can provide a quick search prognosis at the onset of an adult unrelated donor (URD) search could be a useful tool for transplant physicians. We aimed to determine whether patient human leukocyte Ag genotype frequency (GF) could be used as a surrogate measure of whether or not a potential 10/10 and/or 9/10 URD in the Be The Match Registry (BTMR) can be identified for the patient. GF was assigned on a training data set of 2410 patients that searched the BTMR using the reported ethnic group.
View Article and Find Full Text PDFThe search for a suitable human leukocyte antigen (HLA)-matched unrelated adult stem cell donor (URD) or umbilical cord blood unit (UCB) is a complex process. The National Marrow Donor Program (NMDP) developed a search algorithm known as HapLogic, which is currently provided within the NMDP Traxis application. The HapLogic algorithm has been in use since 2006 and has advanced URD/UCB HLA-matching technology.
View Article and Find Full Text PDFBiol Blood Marrow Transplant
April 2016
Estimation of the National Marrow Donor Program's Be The Match Registry 8/8 (HLA-A, -B, -C, and -DRB1) high-resolution (HR) unrelated donor (URD) match rate was determined in a prior study for each of the 4 most frequent patient race/ethnic groups in the United States: white (WH), Hispanic (HIS), Asian/Pacific Islander (API), and African American (AFA). For patients without an 8/8 HLA-matched URD, a 7/8 match, with a single allele or antigen mismatch, is often accepted by many transplant centers. A follow-up study was designed to determine the 7/8 or better match rate among the 4 major race/ethnic groups, using the same study cohort.
View Article and Find Full Text PDFThe / locus at chromosome 9p21 encoding , and is a major tumor suppressor locus, constituting an important barrier for tumor growth. It is frequently inactivated in cancers, especially in urothelial carcinoma (UC). In addition to deletions and DNA hypermethylation, further epigenetic mechanisms might underlie its repression.
View Article and Find Full Text PDFBiol Blood Marrow Transplant
September 2015
Natural killer cells are regulated by killer cell immunoglobulin-like receptor (KIR) interactions with HLA class I ligands. Several models of natural killer cell reactivity have been associated with improved outcomes after myeloablative allogeneic hematopoietic cell transplantation (HCT), but this issue has not been rigorously addressed in reduced-intensity conditioning (RIC) unrelated donor (URD) HCT. We studied 909 patients undergoing RIC-URD HCT.
View Article and Find Full Text PDFBiol Blood Marrow Transplant
January 2015
The National Marrow Donor Program's Be The Match Registry(®) facilitates the worldwide utilization of unrelated donor (URD) grafts for patients in need of a hematopoietic cell transplantation. In this study, we estimate the URD match rate for patients of White (WH), Hispanic (HIS), Asian/Pacific Islander (API), and African American/Black (AFA) race and ethnic groups. We chose 1344 URD at random as "pseudo-patients" (PP) to estimate the likelihood of finding an 8/8 or 10/10 high-resolution HLA-A,-B,-C,-DRB1 (and -DQB1) matched URD.
View Article and Find Full Text PDFThe National Marrow Donor Program (NMDP) is committed to maintaining accurate human leukocyte antigen (HLA) data for each of the 11.5 million volunteer donors on the Be The Match Registry(®) . Qualitative data analysis identified five population specific alleles suspect of being incorrectly characterized.
View Article and Find Full Text PDFWe examined current outcomes of unrelated donor allogeneic hematopoietic cell transplantation (HCT) to determine the clinical implications of donor-recipient HLA matching. Adult and pediatric patients who had first undergone myeloablative-unrelated bone marrow or peripheral blood HCT for acute myelogenous leukemia, acute lymphoblastic leukemia, chronic myelogenous leukemia, and myelodysplastic syndrome between 1999 and 2011 were included. All had high-resolution typing for HLA-A, -B, -C, and -DRB1.
View Article and Find Full Text PDFHLA-DP antigens are beta-alpha heterodimers encoded by polymorphic HLA-DPB1 and -DPA1 alleles, respectively, in strong linkage disequilibrium (LD) with each other. Non-permissive unrelated donor (UD)-recipient HLA-DPB1 mismatches across three different T-cell epitope (TCE) groups are associated with increased mortality after hematopoietic SCT (HCT), but the role of HLA-DPA1 is unclear. We studied 1281 onco-hematologic patients after 10/10 HLA-matched UD-HCT facilitated by the National Marrow Donor Program.
View Article and Find Full Text PDFNon-Hodgkin lymphoma (NHL) disproportionately affects older patients, who do not often undergo allogeneic hematopoietic cell transplantation (HCT). We analyzed Center for International Blood and Marrow Transplant Research data on 1248 patients age ≥40 years receiving reduced-intensity conditioning (RIC) or nonmyeloablative (NMA) conditioning HCT for aggressive (n = 668) or indolent (n = 580) NHL. Aggressive lymphoma was more frequent in the oldest cohort 49% for age 40 to 54 versus 57% for age 55 to 64 versus 67% for age ≥65; P = .
View Article and Find Full Text PDFAdolescents and young adults (AYAs, ages 15 to 40 years) with cancer have not experienced survival improvements to the same extent as younger and older patients. We compared changes in survival after myeloablative allogeneic hematopoietic cell transplantation (HCT) for acute lymphoblastic leukemia (ALL) among children (n = 981), AYAs (n = 1218), and older adults (n = 469) who underwent transplantation over 3 time periods: 1990 to 1995, 1996 to 2001, and 2002 to 2007. Five-year survival varied inversely with age group.
View Article and Find Full Text PDFBiol Blood Marrow Transplant
October 2013
Advances in hematopoietic cell transplantation (HCT) have led to an increasing number of transplant survivors. To adequately support their healthcare needs, there is a need to know the prevalence of HCT survivors. We used data on 170,628 recipients of autologous and allogeneic HCT reported to the Center for International Blood and Marrow Transplant Research from 1968 to 2009 to estimate the current and future number of HCT survivors in the United States.
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