RESUMO
ABSTRACT: Despite the global unrelated donor (URD) registry size, the degree to which URD availability is a transplant barrier is not established. We evaluated the availability of 3,843 URDs requested for 455 diverse adult patients (predominantly with acute leukemia). URDs for non-Europeans were more likely to be domestic and had markedly lower Donor Readiness scores. Of URDs requested for confirmatory HLA-typing (CT) alone (ie, without simultaneous workup), 1,894 of 3,529 (54%) were available. Availability of domestic URDs was 45%. Donor Readiness score was highly predictive of CT availability. More non-European patients (n = 120) than Europeans (n = 335) had >10 URDs requested and <5 available. Of workup requests (after CT or CT-workup), <70% (604/889 [68%]) were available. More non-Europeans had <2 URDs available. URD availability for CT was markedly worse for non-Europeans, with availabilities for African, non-Black Hispanic, and Asian patients being 150/458 (33%), 120/258 (47%), and 119/270 (44%), respectively, with further decrements in URD workup availability. Our data suggest the functional size of the URD pool is much smaller than appreciated, mandating major operational changes for transplant centers and donor registries. Likelihood of donor availability should have a high priority in donor selection. Considering patient ancestry and URD Donor Readiness scores, centers should pursue, and registries permit, simultaneous pursuit of many URDs and abandon futile searches. Patients should be informed about their likelihood of donor availability and alternative options. Finally, although registries should address high URD attrition and speed procurement, use of all HLA-disparate graft types is needed to facilitate timely transplant for all.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Doadores não Relacionados , Humanos , Doadores não Relacionados/provisão & distribuição , Masculino , Transplante Homólogo , Feminino , Adulto , Etnicidade , Sistema de Registros , Pessoa de Meia-Idade , Grupos Raciais , VoluntáriosRESUMO
The impact of the coronavirus disease 2019 (COVID-19) pandemic on hematopoietic cell transplant (HCT) donor registries and transplant center (TC) practices is underreported. This article reports on the National Marrow Donor Program (NMDP) Be The Match Registry and its coordinating the provision of unrelated donor (URD) products to domestic and international TCs during the initial 3 months of the COVID-19 pandemic (March through May 2020). Specifically, NMDP data are presented for disease indications for transplant, URD search volumes and availability, graft requests and processing, courier utilization and performance, and conversion rates from formal donor search and workup to graft collection and shipment. Data following the onset of COVID-19 are compared to the immediate 3 months prior to the COVID-19 pandemic (December 2019 through February 2020) and the same quarter 1 year prior to COVID-19 (March through May 2019). During the initial onset of COVID-19 and compared to 1 year prior, TCs requested and the NMDP performed less donor searches. More multiple URD and direct to workup requests were processed by the NMDP, which likely reflected reductions in donor availability. Yet TCs continued to perform allogeneic transplants for acute disease indications like acute leukemia and myelodysplasia, using more cryopreserved grafts than before COVID-19. In comparison to prepandemic patient cycle conversion rates and durations, the NMDP was able to convert patient cycles at nearly the same or higher rates and in similar or shorter periods of time. Last, despite significant challenges caused by the pandemic, including interruptions in domestic courier services and travel restrictions, graft products were delivered to and received by TCs in similar periods of time than before COVID-19. Taken together, these data show that NMDP service line operations continued to function effectively during the early phases of the COVID-19 pandemic, ensuring requests for and delivery of URD products to domestic and international allogeneic HCT recipients.
Assuntos
COVID-19/epidemiologia , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicas/terapia , Pandemias , SARS-CoV-2 , Doadores não Relacionados/provisão & distribuição , Humanos , Sistema de Registros , Transplante HomólogoRESUMO
BACKGROUND: Recruitment of committed unrelated hematopoietic stem cell donors from the most-needed demographics remains a challenge for donor recruitment organizations worldwide. Multimedia resources are gaining attention as a modality to support recruitment efforts; however, there is a lack of guidance for the development of such tools. This qualitative study explores the perspectives of eligible stem cell donors on an educational whiteboard video about stem cell donation, generating insights into how whiteboard videos and related multimedia may be optimized for donor recruitment. STUDY DESIGN AND METHODS: Eight semistructured focus groups were conducted with 38 potential donors from the most-needed demographics (young, male, and non-Caucasian) after they had watched a 3.5-minute whiteboard video explaining key concepts in stem cell donation (https://youtu.be/V4fVBtxnWfM). Constructivist grounded theory was used to identify themes and to develop a framework for understanding participants' preferred features of recruitment multimedia. RESULTS: Participants identified a range of features contributing to the effectiveness of recruitment multimedia, adding that the whiteboard video is an effective, integrated, and readily accessible format for supporting donor recruitment. Topics that participants felt are important to address include knowledge gaps regarding donation procedures, concerns about donor safety, and the particular need for specific donor demographics. Suggested avenues for improvement include the addition of donor/recipient/patient personal experiences, attention-grabbing hooks, and a call to action including opportunities for further learning. CONCLUSIONS: Several considerations were generated to inform the development of future multimedia for donor education/recruitment and are relevant to donor recruitment organizations worldwide.
Assuntos
Multimídia/estatística & dados numéricos , Doadores de Tecidos/educação , Doadores de Tecidos/provisão & distribuição , Doadores não Relacionados/provisão & distribuição , Adolescente , Adulto , Emoções , Etnicidade , Estudos de Avaliação como Assunto , Grupos Focais/métodos , Células-Tronco Hematopoéticas , Humanos , Masculino , Segurança , Inquéritos e Questionários/estatística & dados numéricos , Doadores de Tecidos/psicologia , Doadores não Relacionados/estatística & dados numéricos , Adulto JovemRESUMO
The COVID-19 pandemic has created significant barriers to timely donor evaluation, cell collection, and graft transport for allogeneic hematopoietic stem cell transplantation (allo-HCT). To ensure availability of donor cells on the scheduled date of infusion, many sites now collect cryopreserved grafts before the start of pretransplantation conditioning. Post-transplantation cyclophosphamide (ptCY) is an increasingly used approach for graft-versus-host disease (GVHD) prophylaxis, but the impact of graft cryopreservation on the outcomes of allo-HCT using ptCY is not known. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we compared the outcomes of HCT using cryopreserved versus fresh grafts in patients undergoing HCT for hematologic malignancy with ptCY. We analyzed 274 patients with hematologic malignancy undergoing allo-HCT between 2013 and 2018 with cryopreserved grafts and ptCY. Eighteen patients received bone marrow grafts and 256 received peripheral blood stem cell grafts. These patients were matched for age, graft type, disease risk index (DRI), and propensity score with 1080 patients who underwent allo-HCT with fresh grafts. The propensity score, which is an assessment of the likelihood of receiving a fresh graft versus a cryopreserved graft, was calculated using logistic regression to account for the following: disease histology, Karnofsky Performance Score (KPS), HCT Comorbidity Index, conditioning regimen intensity, donor type, and recipient race. The primary endpoint was overall survival (OS). Secondary endpoints included acute and chronic graft-versus-host disease (GVHD), non-relapse mortality (NRM), relapse/progression and disease-free survival (DFS). Because of multiple comparisons, only P values <.01 were considered statistically significant. The 2 cohorts (cryopreserved and fresh) were similar in terms of patient age, KPS, diagnosis, DRI, HCT-CI, donor/graft source, and conditioning intensity. One-year probabilities of OS were 71.1% (95% confidence interval [CI], 68.3% to 73.8%) with fresh grafts and 70.3% (95% CI, 64.6% to 75.7%) with cryopreserved grafts (P = .81). Corresponding probabilities of OS at 2 years were 60.6% (95% CI, 57.3% to 63.8%) and 58.7% (95% CI, 51.9% to 65.4%) (P = .62). In matched-pair regression analysis, graft cryopreservation was not associated with a significantly higher risk of mortality (hazard ratio [HR] for cryopreserved versus fresh, 1.05; 95% CI, .86 to 1.29; P = .60). Similarly, rates of neutrophil recovery (HR, .91; 95% CI, .80 to 1.02; P = .12), platelet recovery (HR, .88; 95% CI, .78 to 1.00; P = .05), grade III-IV acute GVHD (HR, .78; 95% CI, .50 to 1.22; P = .27), NRM (HR, 1.16; 95% CI, .86 to 1.55; P = .32) and relapse/progression (HR, 1.21; 95% CI, .97 to 1.50; P = .09) were similar with cryopreserved grafts versus fresh grafts. There were somewhat lower rates of chronic GVHD (HR, 78; 95% CI, .61 to .99; P = .04) and DFS (HR for treatment failure, 1.19; 95% CI, 1.01 to 1.29; P = .04) with graft cryopreservation that were of marginal statistical significance after adjusting for multiple comparisons. Overall, our data indicate that graft cryopreservation does not significantly delay hematopoietic recovery, increase the risk of acute GVHD or NRM, or decrease OS after allo-HCT using ptCY.
Assuntos
Transplante de Medula Óssea/métodos , Infecções por Coronavirus/epidemiologia , Criopreservação/métodos , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia/terapia , Linfoma/terapia , Síndromes Mielodisplásicas/terapia , Pneumonia Viral/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Estudos de Coortes , Ciclofosfamida/uso terapêutico , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/patologia , Teste de Histocompatibilidade , Humanos , Leucemia/imunologia , Leucemia/mortalidade , Leucemia/patologia , Linfoma/imunologia , Linfoma/mortalidade , Linfoma/patologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Pandemias , Irmãos , Análise de Sobrevida , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Estados Unidos/epidemiologia , Doadores não Relacionados/provisão & distribuiçãoRESUMO
Allogeneic 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. In this summary, the National Marrow Donor Program (NMDP) and the Center for International Blood and Marrow Transplant Research, jointly with the NMDP Histocompatibility Advisory Group, provide evidence-based guidelines for optimal selection of unrelated donors and cord blood units.
Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical/normas , Seleção do Doador/normas , Sangue Fetal , Transplante de Células-Tronco Hematopoéticas/normas , Doadores não Relacionados , Adulto , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Seleção do Doador/métodos , Sangue Fetal/imunologia , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Teste de Histocompatibilidade/métodos , Teste de Histocompatibilidade/normas , Humanos , Recém-Nascido , Sistema de Registros , Doadores não Relacionados/provisão & distribuiçãoAssuntos
Doenças Ósseas Metabólicas/terapia , Medula Óssea/anormalidades , Disceratose Congênita/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Doadores de Tecidos , Doadores não Relacionados/provisão & distribuição , Doenças Ósseas Metabólicas/classificação , Doenças Ósseas Metabólicas/patologia , Medula Óssea/patologia , Disceratose Congênita/classificação , Disceratose Congênita/patologia , Feminino , Humanos , Lactente , Prognóstico , Retina/patologia , Condicionamento Pré-Transplante , Transplante HomólogoRESUMO
A human leukocyte antigen (HLA)-matched unrelated donor is the primary alternative donor for allogeneic hematopoietic cell transplantation in Japan. In considering an optimal donor registry size, the availability of HLA-matched donors is important. In this study, the probability of finding an HLA-A, -B, -C, and -DRB1 allele-matched donor was estimated using two different methods based on the haplotype frequencies in the Japanese population: an actual measurement method (AMM) and a formula method (FM). According to AMM, the probabilities of finding an HLA-matched donor were 40.5% in 100,000 donors, 54.4% in 300,000, 60.0% in 500,000, and 63.4% in 700,000. On the other hand, according to FM, the probabilities were 47.8% in 100,000 donors, 59.9% in 300,000, 65.3% in 500,000, and 68.8% in 700,000. The probabilities increased by 8.6 or 7.7%, 3.2 or 3.1%, 2.1 or 1.9%, and 1.6 or 1.3% in AMM or FM, respectively, as the registry size increased by 100,000. The rate of increase in the probability of finding an HLA-matched donor will become smaller as the registry size increases due to the diversity of haplotypes. Therefore, it is important to set a target donor registry size for efficient donor recruitment by considering the haplotype frequencies in the population.
Assuntos
Antígenos HLA/imunologia , Histocompatibilidade/imunologia , Doadores não Relacionados/provisão & distribuição , Alelos , Genótipo , Haplótipos/genética , Haplótipos/imunologia , Humanos , Japão/epidemiologia , Modelos Genéticos , Probabilidade , Sistema de Registros , Tamanho da AmostraRESUMO
Donor availability for allogeneic transplantation remains an important factor in determining outcomes of a successful transplant. We examined outcomes of 242 patients treated over 3 years who had a matched unrelated donor (MUD) search at our institution. One hundred sixty patients (66%) had a 10 of 10 MUD identified, and 85 (53%) proceeded to MUD transplantation. White patients and those with common haplotypes were more likely to have a MUD identified (odds ratio [OR], 7.4 [P < .0001]; OR, 41.6 [P < .0001]), and were more likely to proceed to transplantation with a MUD (OR, 11.2 [P < .0001]; OR, 85.1 [P = .002]). In addition, patients who were newly diagnosed/in remission at the time of MUD search had a higher probability of receiving a transplant (OR, 2.01 [P = .013]) and better progression-free survival (PFS; P < .0001). In multivariate analysis for patients who received a transplant, donor type did not influence PFS at 3 years, which was 40% for MUD and 57% for haploidentical transplants, respectively (hazard ratio, 1.2 [P = .50]). In conclusion, race, haplotype frequency, and disease status at the time of MUD search influence the probability of identifying a MUD and receiving a transplant. Patients with a low likelihood of receiving a MUD transplant may proceed to a haploidentical transplant as soon as indicated, as this approach does not appear to compromise transplant outcomes.
Assuntos
Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Teste de Histocompatibilidade , Doadores não Relacionados/provisão & distribuição , Adolescente , Adulto , Idoso , Criança , Haplótipos , Neoplasias Hematológicas/mortalidade , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Pessoa de Meia-Idade , Indução de Remissão , Fatores de Risco , Análise de Sobrevida , Transplante Haploidêntico , Transplante Homólogo , Adulto JovemRESUMO
A strategy to rapidly determine if a matched unrelated donor (URD) can be secured for allograft recipients is needed. We sought to validate the accuracy of (1) HapLogic match predictions and (2) a resultant novel Search Prognosis (SP) patient categorization that could predict 8/8 HLA-matched URD(s) likelihood at search initiation. Patient prognosis categories at search initiation were correlated with URD confirmatory typing results. HapLogic-based SP categorizations accurately predicted the likelihood of an 8/8 HLA-match in 830 patients (1530 donors tested). Sixty percent of patients had 8/8 URD(s) identified. Patient SP categories (217 very good, 104 good, 178 fair, 33 poor, 153 very poor, 145 futile) were associated with a marked progressive decrease in 8/8 URD identification and transplantation. Very good to good categories were highly predictive of identifying and receiving an 8/8 URD regardless of ancestry. Europeans in fair/poor categories were more likely to identify and receive an 8/8 URD compared with non-Europeans. In all ancestries very poor and futile categories predicted no 8/8 URDs. HapLogic permits URD search results to be predicted once patient HLA typing and ancestry is obtained, dramatically improving search efficiency. Poor, very poor, andfutile searches can be immediately recognized, thereby facilitating prompt pursuit of alternative donors.
Assuntos
Algoritmos , Teste de Histocompatibilidade , Doadores não Relacionados/provisão & distribuição , Adulto , Idoso , Transplante de Células-Tronco Hematopoéticas , Humanos , Pessoa de Meia-Idade , Probabilidade , Grupos Raciais , Transplante HomólogoRESUMO
BACKGROUND: Patients with blood, immune, or metabolic diseases may require a stem cell transplant as part of their treatment. However, 70% of patients do not have a suitable human leukocyte antigen match in their family, and need an unrelated donor. Individuals can register as potential donors at stem cell drives, where they provide consent and a tissue sample for human leukocyte antigen typing. The ideal donors are young, male, and from a diversity of ethnic backgrounds. However, in Canada, non-Caucasian males ages 17 to 35 years represent only 8.8% of listed donors. STUDY DESIGN AND METHODS: The Stem Cell Club is a non-profit organization founded in 2011 in Canada that aims to augment recruitment of the most needed donors. The initiative published a recruitment toolkit online (www.stemcellclub.ca). Currently, there are 12 chapters at universities across Canada. RESULTS: To date, the Stem Cell Club has recruited 6585 potential registrants, representing 1.63% of donors on Canada's donor-database. Of the recruited registrants, 58.3% were male; 60.3% of males self-reported as non-Caucasian, and 78.5% were ages 17 to 25 years. From 2015 to 2016, the initiative recruited 13.7% of all ethnically diverse males ages 17 to 35 years listed in Canada's donor database. Data from this initiative demonstrate sustainability and performance on key indicators of stem cell drive quality. CONCLUSION: The Stem Cell Club has developed a capacity to recruit 2600 donors annually, with the majority being males with a high degree of ethnic diversity. The initiative enhances the quality of Canada's unrelated donor-database, improving the chances that patients in need of an unrelated donor will find a match for transplant. The Stem Cell Club is a model relevant to recruitment organizations around the world.
Assuntos
Doadores de Sangue/provisão & distribuição , Seleção de Pessoal/métodos , Doadores não Relacionados/provisão & distribuição , Feminino , Humanos , Masculino , Seleção de Pessoal/organização & administração , Transplante de Células-TroncoAssuntos
Antígenos HLA/imunologia , Histocompatibilidade , Doadores Vivos/provisão & distribuição , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirurgia , Transplante de Células-Tronco/métodos , Doadores não Relacionados/provisão & distribuição , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Fatores de Risco , Transplante de Células-Tronco/efeitos adversos , Transplante Haploidêntico , Transplante Homólogo , Resultado do TratamentoRESUMO
The availability of cord blood (CB) and haploidentical (haplo) donors in all patient populations is not established. We have investigated the addition of haplo-CD34+ cells to CB grafts (haplo-CBT) to speed myeloid engraftment. Thus, we have prospectively assessed CB and haplo donor availability in adult patients without 8/8 HLA-allele matched unrelated donors (URDs). Analysis of 89 patients eligible for haplo-CBT revealed 4 distinct patient groups. First, 6 patients (7% of total, 33% non-European) underwent CBT only as they had no suitable family members to type. In group 2, 49 patients (45% non-European) received haplo-CBT using the first haplo donor chosen. Group 3 (n = 21, 76% non-European) underwent CBT with/without haplo. In this group, the first haplo donor chosen failed clearance in 20 patients and transplantation was too urgent to permit donor evaluation in 1. Fifty-three haplo donors were evaluated (2 to 6 per patient) for 21 group 3 patients, and 43 of 53 (81%) haplos failed clearance for predominantly medical and/or psychosocial reasons. Group 4, (n = 13, 85% non-European with a high median weight of 96 kilograms) had no CB grafts with/without no haplo donors. Overall, African patients had the worst donor availability with only 65% having a suitable CB graft and only 44% having a suitable haplo donor. Additionally, in non-European patients, a greater number of haplos required evaluation/patient to secure a suitable haplo graft. Although these data should be confirmed in a larger study, it suggests that there are barriers to the availability of both CB and haplo grafts in adult patients without 8/8 URDs, especially in those with African ancestry, and has multiple practical implications for patient management.
Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Seleção do Doador/métodos , Grupos Raciais , Transplante Haploidêntico/métodos , Doadores não Relacionados/provisão & distribuição , Adolescente , Adulto , Idoso , Transplante de Células-Tronco de Sangue do Cordão Umbilical/etnologia , Neoplasias Hematológicas/terapia , Histocompatibilidade , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto JovemRESUMO
Improving haematopoietic cell transplantation outcomes by selection of an HLA-matched unrelated donor is best practice; however, donor selection by secondary characteristics is controversial. We studied 1271 recipients with haematological malignancies who underwent T-cell-depleted allografts and had complete data on HLA-matching status for six loci (HLA-A, -B, -C, -DRB1, -DQB1, -DPB1) and clinical outcome data. Five-year overall survival was 40.6%. HLA mismatching (at HLA-A, -B, -C, -DRB1, -DQB1) relative risk (RR) 1.22, 95% confidence interval (CI) 1.2-1.5, P=0.033 for 1 mismatch and RR 1.46, 95% CI 1.1-1.9, P=0.009 for >1 mismatch) and CMV mismatching (RR 1.37, 95% CI 1.2-1.6, P<0.001) were significantly associated with inferior survival. Donors aged <30 years showed a trend towards better survival. The multivariate model for mortality, combining CMV and HLA-match status, found an RR of 1.36 (95% CI 1.1-1.7, P=0.003) for HLA matched/CMV mismatched, an RR of 1.22 (95% CI 0.99-1.5, P=0.062) for HLA mismatched/CMV matched and an RR of 1.81 (95% CI 1.4-2.3, P=<0.001) for HLA/ CMV mismatched, compared with the HLA/CMV-matched recipients. These data suggest that HLA and CMV matching status should be considered when selecting unrelated donors and that CMV matching may abrogate the effect of an HLA mismatch.
Assuntos
Citomegalovirus/imunologia , Antígenos HLA/imunologia , Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Doadores não Relacionados/provisão & distribuição , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Histocompatibilidade , Humanos , Depleção Linfocítica , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Testes Sorológicos , Análise de Sobrevida , Adulto JovemRESUMO
Allogeneic stem cell transplantation (allo-SCT) following a non-myeloablative (NMA) or reduced-intensity conditioning (RIC) is considered a valid approach to treat patients with refractory/relapsed Hodgkin lymphoma (HL). When an HLA-matched donor is lacking a graft from a familial haploidentical (HAPLO) donor, a mismatched unrelated donor (MMUD) or cord blood (CB) might be considered. In this retrospective study, we compared the outcome of patients with HL undergoing a RIC or NMA allo-SCT from HAPLO, MMUD or CB. Ninety-eight patients were included. Median follow-up was 31 months for the whole cohort. All patients in the HAPLO group (N=34) received a T-cell replete allo-SCT after a NMA (FLU-CY-TBI, N=31, 91%) or a RIC (N=3, 9%) followed by post-transplant cyclophosphamide. After adjustment for significant covariates, MMUD and CB were associated with significantly lower GvHD-free relapse-free survival (GRFS; hazard ratio (HR)=2.02, P=0.03 and HR=2.43, P=0.009, respectively) compared with HAPLO donors. In conclusion, higher GRFS was observed in Hodgkin lymphoma patients receiving a RIC or NMA allo-SCT with post-transplant cyclophosphamide from HAPLO donors. Our findings suggest they should be favoured over MMUD and CB in this setting.
Assuntos
Ciclofosfamida/uso terapêutico , Doença de Hodgkin/terapia , Transplante de Células-Tronco/métodos , Condicionamento Pré-Transplante/métodos , Transplante Haploidêntico , Adulto , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Intervalo Livre de Doença , Feminino , Seguimentos , Doença Enxerto-Hospedeiro , Antígenos HLA , Histocompatibilidade , Doença de Hodgkin/mortalidade , Humanos , Masculino , Estudos Retrospectivos , Transplante de Células-Tronco/normas , Transplante Homólogo , Doadores não Relacionados/provisão & distribuiçãoRESUMO
The availability of hematopoietic cell transplantation as curative therapy for blood disorders has been dramatically improved through a better understanding of the human leukocyte antigen (HLA) barrier. Although a fully compatible unrelated donor is preferable, transplantation from donors with a limited degree of HLA mismatching is associated with acceptable outcomes in many cases. Research on the limits of HLA mismatching, and the features that define permissible HLA mismatches will continue to enable transplantation to be more broadly available to patients in need.
Assuntos
Antígenos HLA/genética , Doenças Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas/métodos , Teste de Histocompatibilidade/estatística & dados numéricos , Sistema de Registros , Doadores não Relacionados/provisão & distribuição , Alelos , Alergia e Imunologia/história , Doença Enxerto-Hospedeiro/prevenção & controle , Antígenos HLA/classificação , Antígenos HLA/imunologia , Doenças Hematológicas/genética , Doenças Hematológicas/imunologia , Doenças Hematológicas/patologia , Transplante de Células-Tronco Hematopoéticas/história , História do Século XX , Humanos , Itália , Agonistas Mieloablativos/uso terapêutico , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Doadores não Relacionados/classificação , Recursos HumanosRESUMO
BACKGROUND: 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-AËCËBËDRB1ËDQB1, were identified. Each search had up to 20 potential 10/10 or 8/8 URDs typed to determine the likelihood of an allele match. RESULTS: The incidence of patient searches without haplotype pairs in a single ethnic group in the HFD was 1.2% (N=144 out of 12,172) and a majority of these patients (117; 81%) had one uncommon haplotype previously uncharacterized in the HFD. Non-White patients had the highest incidence of UPH. Importantly, no patients with UPH had a 10/10 URD identified. The transplant rate among UPH patients was 15%, and a majority of these patients utilized cord blood units as their transplant stem cell source. CONCLUSION: Therefore, the HLA HFD that informs the HapLogic matching algorithm is thorough as UPH patient searches were infrequent. Since such patients are highly unlikely to have a fully 10/10 matched URD identified, this study supports the identification of alternative stem cell sources including cord blood or a mismatched URD early in the search process.
Assuntos
Algoritmos , Transplante de Medula Óssea/métodos , Transplante de Células-Tronco de Sangue do Cordão Umbilical/métodos , Antígenos HLA/genética , Transplante de Células-Tronco Hematopoéticas/métodos , Sistema de Registros , Alelos , Transplante de Células-Tronco de Sangue do Cordão Umbilical/etnologia , Expressão Gênica , Frequência do Gene , Antígenos HLA/classificação , Antígenos HLA/imunologia , Haplótipos , Transplante de Células-Tronco Hematopoéticas/etnologia , Teste de Histocompatibilidade , Humanos , Probabilidade , Grupos Raciais , Estados Unidos , Doadores não Relacionados/estatística & dados numéricos , Doadores não Relacionados/provisão & distribuiçãoAssuntos
Remoção de Componentes Sanguíneos/ética , Mobilização de Células-Tronco Hematopoéticas/ética , Transplante de Células-Tronco Hematopoéticas/ética , Leucemia Mieloide Aguda/terapia , Doadores não Relacionados/ética , Remoção de Componentes Sanguíneos/métodos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Mobilização de Células-Tronco Hematopoéticas/métodos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Leucemia Mieloide Aguda/patologia , Masculino , Pessoa de Meia-Idade , Condicionamento Pré-Transplante , Transplante Homólogo , Resultado do Tratamento , Doadores não Relacionados/psicologia , Doadores não Relacionados/provisão & distribuiçãoRESUMO
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. To determine the likelihood of identifying a DPB1 permissive-matched (includes both allele-matched and DPB1-permissive mismatched) unrelated donor for patients with high-resolution matches at 10/10 HLA-A, -B,- C, -DRB1, and -DQB1 in the Be The Match Registry, preliminary search requests from United States' transplant centers for 595 DPB1-typed patients were evaluated for existence of a DPB1 permissive-matched donor, identified either among already typed donors or by prospective DPB1 typing. The baseline DPB1 permissive match rate was 69% and improved to 80% after additional donor DPB1 typing (median, 4 donors per patient). When seeking a 10/10-matched, young (18- to 32-year-old) donor in the registry, the probability of finding a DPB1 permissive-matched donor started lower at 59% and improved to 70% after additional DPB1 testing. Our results show that most patients with a 10/10 match can find a DPB1 permissive-matched donor.
Assuntos
Epitopos de Linfócito T/imunologia , Cadeias beta de HLA-DP/análise , Doadores não Relacionados/provisão & distribuição , Adolescente , Adulto , Alelos , Etnicidade , Transplante de Células-Tronco Hematopoéticas/métodos , Teste de Histocompatibilidade , Humanos , Adulto JovemAssuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical/estatística & dados numéricos , Doadores de Tecidos/provisão & distribuição , Doadores não Relacionados/provisão & distribuição , Antígenos HLA/imunologia , Transplante de Células-Tronco Hematopoéticas , Teste de Histocompatibilidade , Humanos , Transplante HomólogoRESUMO
Despite over 20 million unrelated donors being listed worldwide, donor attrition at the confirmatory typing (CT) stage of donor acquisition is a key source of delay. Anthony Nolan undertook a study of CT requests from 2010 to 2011 to identify factors associated with attrition. Of 7541 CT requests, 38.2% were cancelled for donor reasons. Of these, 19.4% were personal, 34.1% medical, 36% no contact, 7.9% emigrated and 2.6% others. African (odds ratio (OR) 2.78, P<0.001), African-Caribbean (OR 3.07, P<0.001), Asian (OR 2.65, P<0.001), Jewish (OR 1.54, P=0.009) and Mediterranean (OR=2.38, P<0.001) donors were more likely not to be available compared to Caucasian donors. Female donors were also more likely not to be available (OR=1.32, P<0.001): primarily due to pregnancy. Older donors were less likely to be available in univariate analysis, but this association was not significant after controlling for other factors. Blood donors and those recruited within the past five years had lower rates of attrition. Accumulation of additional attrition-associated characteristics for a given donor was associated with progressively greater odds of attrition (OR 1.99, 2.52, 3.4 and 5.53, respectively, for 1, 2, 3 and 4 risk factors, P<0.001). Donor registries must develop evidence-driven strategies to recruit and retain the most reliable donors.