Dataset Information

HLA-A disparities illustrate challenges for ranking the impact of HLA mismatches on bone marrow transplant outcomes in the United States.

ABSTRACT: HLA disparity between hematopoietic stem cell donors and recipients is one of the most important factors influencing transplant outcomes, but there are no well-accepted guidelines to aid in selecting the optimal donor among several HLA mismatched donors. In this report, HLA-A is used as a model to illustrate factors that are barriers to delineating the relationship between specific HLA mismatches and transplant outcomes in the United States. Patients in this investigation received transplants for hematologic malignancies that were facilitated by the National Marrow Donor Program (NMDP) between 1990 and 2002 (n = 4226). High-resolution HLA typing was performed for HLA-A, -B, -C, -DRB1, -DQA1, -DQB1, -DPA1, and -DPB1. HLA-A mismatches were observed in 745 donor-recipient pairs and 62% of these pairs also had disparities at HLA-B, -C, and/or -DRB1. The HLA-A mismatches involved 190 different combinations of HLA-A alleles and 51% of these were observed in only 1 pair. Addition of a single HLA-A disparity when HLA-B, -C, and -DRB1 were matched (n = 282) was associated with increased mortality (odds ratio [OR] = 1.32, confidence interval [CI] 1.07-1.63). When HLA-B, -C, and -DRB1 were matched, the most frequent HLA-A mismatches were HLA-A*0201:0205 (n = 28), HLA-A *0301:0302 (n = 15), HLA-A *0201:0206 (n = 15), HLA-A *0201:6801 (n = 12), HLA-A*0101:1101 (n = 11), and HLA-A*0101:0201 (n = 10). There were no statistically significant relationships between any of these disparities and transplant outcomes (engraftment, acute and chronic graft-versus-host disease [aGVHD, cGVHD] relapse, treatment-related mortality [TRM], or overall survival [OS]) when adjustments for multiple comparisons were considered. Achieving 80% power to detect an effect of any 1 of these 6 HLA-A disparities on survival is estimated to require a total transplant population of 11,000 to more than 1 million U.S. donor-recipient pairs depending upon the HLA disparity. Thus, alternative approaches are required to develop a clinically relevant ranking system for specific HLA disparities in the United States.

SUBMITTER: Baxter-Lowe LA

PROVIDER: S-EPMC2747529 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

HLA-A disparities illustrate challenges for ranking the impact of HLA mismatches on bone marrow transplant outcomes in the United States.

Baxter-Lowe Lee Ann LA Maiers Martin M Spellman Stephen R SR Haagenson Michael D MD Wang Tao T Fernandez-Vina Marcelo M Marsh Steven G E SG Horowitz Mary M Hurley Carolyn Katovich CK

Biology of blood and marrow transplantation : journal of the American Society for Blood and Marrow Transplantation 20090801 8

HLA disparity between hematopoietic stem cell donors and recipients is one of the most important factors influencing transplant outcomes, but there are no well-accepted guidelines to aid in selecting the optimal donor among several HLA mismatched donors. In this report, HLA-A is used as a model to illustrate factors that are barriers to delineating the relationship between specific HLA mismatches and transplant outcomes in the United States. Patients in this investigation received transplants fo ...[more]

PMID: 19589487

Similar Datasets

Project description:Background and objectivesThe current allocation algorithm for deceased donor kidney transplantation takes into consideration HLA mismatches at the ABDR loci but not HLA mismatches at other loci, including HLA-DQ. However, the independent effects of incompatibilities for the closely linked HLA-DQ antigens in the context of HLA-DR antigen matched and mismatched allografts are uncertain. We aimed to determine the effect of HLA-DQ mismatches on renal allograft outcomes.Design, setting, participants, & measurementsUsing data from the Australia and New Zealand Dialysis and Transplant Registry, we examined the association between HLA-DQ mismatches and acute rejections in primary live and deceased donor kidney transplant recipients between 2004 and 2012 using adjusted Cox regression models.ResultsOf the 788 recipients followed for a median of 2.8 years (resulting in 2891 person-years), 321 (40.7%) and 467 (59.3%) received zero and one or two HLA-DQ mismatched kidneys, respectively. Compared with recipients who have received zero HLA-DQ mismatched kidneys, those who have received one or two HLA-DQ mismatched kidneys experienced greater numbers of any rejection (50 of 321 versus 117 of 467; P<0.01), late rejections (occurring >6 months post-transplant; 8 of 321 versus 27 of 467; P=0.03), and antibody-mediated rejections (AMRs; 12 of 321 versus 38 of 467; P=0.01). Compared with recipients of zero HLA-DQ mismatched kidneys, the adjusted hazard ratios for any and late rejections in recipients who had received one or two HLA-DQ mismatched kidneys were 1.54 (95% confidence interval [95% CI], 1.08 to 2.19) and 2.85 (95% CI, 1.05 to 7.75), respectively. HLA-DR was an effect modifier between HLA-DQ mismatches and AMR (P value for interaction =0.02), such that the association between HLA-DQ mismatches and AMR was statistically significant in those who have received one or two HLA-DR mismatched kidneys, with adjusted hazard ratio of 2.50 (95% CI, 1.05 to 5.94).ConclusionsHLA-DQ mismatches are associated with acute rejection, independent of HLA-ABDR mismatches and initial immunosuppression. Clinicians should be aware of the potential importance of HLA-DQ matching in the assessment of immunologic risk in kidney transplant recipients.

Project description:BackgroundAlthough kidney transplant improves reproductive function in women with end-stage kidney disease (ESKD), pregnancy in kidney transplant recipients' remains challenging due to the risk of adverse maternal and fetal outcomes.MethodsWe evaluated a retrospective cohort of 7,966 women who were aged 15-45 years and received a kidney transplant between January 1, 2005 and December 31, 2011 from the United States Renal Data System with Medicare as the primary payer for the entire three years after the date of transplantation. Unadjusted and adjusted rates of pregnancy in the first three post-transplant years were calculated, using Poisson regression for the adjustment. Factors associated with pregnancy, including race, were examined using logistic regression.ResultsOverall, 293 pregnancies were identified in 7966 women. The unadjusted pregnancy rate was 13.8 per thousand person-years (PTPY) (95% confidence interval (CI), 12.3-15.5). Pregnancy rates were roughly constant in the years 2005-2011 except in 2005 and 2010. The rate of pregnancy was highest in Hispanic women (21.4 PTPY; 95% CI, 17.2-26.4) and Hispanic women had a higher likelihood of pregnancy as compared to white women (OR, 1.56; CI, 1.12-2.16). Pregnancy rates were lowest in women aged 30-34 years and 35-45 years at transplant, and women aged 30-34 years and 35-45 years at transplant were less likely to ever become pregnant during the follow-up (odds ratio [OR], 0.69; CI, 0.49-0.98 and OR, 0.14; CI 0.09-0.21 respectively) as compared to women aged 25-29 years at time of transplant. Women had higher rates of pregnancy in the second and third-year post-transplant (16.0 PTPY, CI 13.2-19.2 and 16.9 PTPY, CI 14.0-20.4) than in the first-year post-transplant (9.0 PTPY, CI 7.0-11.4). In transplant recipients, pregnancy was more likely in women with ESKD due to cystic disease (OR, 2.42; CI, 1.02-5.74) or glomerulonephritis (OR, 2.14; CI, 1.07-4.31) as compared to women with ESKD due to diabetes.ConclusionHispanic race, younger age, and ESKD cause due to cystic disease or glomerulonephritis are significant factors associated with a higher likelihood of pregnancy. Pregnancy rates have been fairly constant over the last decade. This study improves our understanding of factors associated with pregnancy in kidney transplant recipients.

Project description:BackgroundCorrelation between antibody-mediated rejection (ABMR) and circulating HLA donor-specific antibodies (HLA-DSA) is strong but imperfect in kidney transplant (KT) recipients, raising the possibility of undetected HLA-DSA or non-HLA antibodies contributing to ABMR. Detailed evaluation of the degree of HLA matching together with the identification of non-HLA antibodies in KT may help to decipher the antibody involved.MethodsWe retrospectively assessed patients with transplant biopsies scored following Banff'15 classification. Pre- and post-transplant serum samples were checked for HLA and non-HLA antibodies [MICA-Ab, angiotensin-II type-1-receptor (AT1R)-Ab, endothelin-1 type-A-receptor (ETAR)-Ab and crossmatches with primary aortic endothelial cells (EC-XM)]. We also analyzed HLA epitope mismatches (HLA-EM) between donors and recipients to explore their role in ABMR histology (ABMRh) with and without HLA-DSA.ResultsOne-hundred eighteen patients with normal histology (n = 19), ABMRh (n = 52) or IFTA (n = 47) were studied. ABMRh patients were HLA-DSApos (n = 38, 73%) or HLA-DSAneg (n = 14, 27%). Pre-transplant HLA-DSA and AT1R-Ab were more frequent in ABMRh compared with IFTA and normal histology cases (p = 0.006 and 0.003), without differences in other non-HLA antibodies. Only three ABMRhDSAneg cases showed non-HLA antibodies. ABMRhDSAneg and ABMRhDSApos cases showed similar biopsy changes and graft-survival. Both total class II and DRB1 HLA-EM were associated with ABMRhDSApos but not with ABMRhDSAneg. Multivariate analysis showed that pre-transplant HLA-DSA (OR: 3.69 [1.31-10.37], p = 0.013) and AT1R-Ab (OR: 5.47 [1.78-16.76], p = 0.003) were independent predictors of ABMRhDSApos.ConclusionsIn conclusion, pre-transplant AT1R-Ab is frequently found in ABMRhDSApos patients. However, AT1R-Ab, MICA-Ab, ETAR-Ab or EC-XM+ are rarely found among ABMRhDSAneg patients. Pre-transplant AT1R-Ab may act synergistically with preformed or de novo HLA-DSA to produce ABMRhDSApos but not ABMRhDSAneg. HLA epitope mismatch associates with ABMRhDSApos compared with ABMRhDSAneg, suggesting factors other than HLA are responsible for the damage.

Project description:ImportanceMillions of Americans gained insurance through the state expansion of Medicaid, but several states with large populations of racial/ethnic minorities did not expand their programs.ObjectiveTo investigate the implications of Medicaid expansion for liver transplant (LT) wait-listing trends for racial/ethnic minorities.Design, setting, and participantsA cohort study was performed of adults wait-listed for LT using the United Network of Organ Sharing database between January 1, 2010, and December 31, 2017. Poisson regression and a controlled, interrupted time series analysis were used to model trends in wait-listing rates by race/ethnicity. The setting was LT centers in the United States.Main outcomes and measures(1) Wait-listing rates by race/ethnicity in states that expanded Medicaid (expansion states) compared with those that did not (nonexpansion states) and (2) actual vs predicted rates of LT wait-listing by race/ethnicity after Medicaid expansion.ResultsThere were 75 748 patients (median age, 57.0 [interquartile range, 50.0-62.0] years; 48 566 [64.1%] male) wait-listed for LT during the study period. The cohort was 8.9% Black and 16.4% Hispanic. Black patients and Hispanic patients were statistically significantly more likely to be wait-listed in expansion states than in nonexpansion states (incidence rate ratio [IRR], 1.54 [95% CI, 1.44-1.64] for Black patients and 1.21 [95% CI, 1.15-1.28] for Hispanic patients). After Medicaid expansion, there was a decrease in the wait-listing rate of Black patients in expansion states (annual percentage change [APC], -4.4%; 95% CI, -8.2% to -0.6%) but not in nonexpansion states (APC, 0.5%; 95% CI, -4.0% to 5.2%). This decrease was not seen when Black patients with hepatitis C virus (HCV) were excluded from the analysis (APC, 3.1%; 95% CI, -2.4% to 8.9%), suggesting that they may be responsible for this expansion state trend. Hispanic Medicaid patients without HCV were statistically significantly more likely to be wait-listed in the post-Medicaid expansion era than would have been predicted without Medicaid expansion (APC, 13.2%; 95% CI, 4.0%-23.2%).Conclusions and relevanceThis cohort study found that LT wait-listing rates have decreased for Black patients with HCV in states that expanded Medicaid. Conversely, wait-listing rates have increased for Hispanic patients without HCV. Black patients and Hispanic patients may have benefited differently from Medicaid expansion.

Dataset Information

HLA-A disparities illustrate challenges for ranking the impact of HLA mismatches on bone marrow transplant outcomes in the United States.

Publications

HLA-A disparities illustrate challenges for ranking the impact of HLA mismatches on bone marrow transplant outcomes in the United States.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets