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1.
Am J Transplant ; 23(9): 1388-1400, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37257653

RESUMO

Technological advances in the field of histocompatibility have allowed us to define anti-human leukocyte antigen (HLA) antibody specificity at the allelic level. However, how allele-specific antibodies affect organ allocation is poorly studied. We examined allelic specificities of class I HLA antibodies in 6726 consecutive serum samples from 2953 transplant candidates and evaluated their impact on the corresponding crossmatch and organ allocation. Out of 17 class I HLA antigens represented by >1 allele in the LABScreen single antigen bead assay, 12 had potential allele-specific reactivity. Taking advantage of our unbiased cohort of deceased donor-candidate testing (123,135 complement-dependent cytotoxicity crossmatches between 2014 and 2017), we estimated that the presence of allele-specific antibody detected using a single antigen bead assay (median fluorescence intensity, >3000) against only the rare allele was a poor predictor of a positive complement-dependent cytotoxicity crossmatch, with a positive predictive value of 0% to 7%, compared with 52.5% in allele-concordant class I HLA antibodies against A or B locus antigens. Further, we confirmed allele-specific reactivity using flow crossmatch in 3 scenarios: A11:01/A11:02, A68:01/A68:02, and B44:02/B44:03. Our results suggest that allele-specific antibodies may unnecessarily exclude transplant candidates (up to 10%) from organ offers by overcalling unacceptable antigens; incorporation of selective reactivity pattern in allocation may promote precision matching and more equitable allocation.


Assuntos
Antígenos de Histocompatibilidade Classe I , Isoanticorpos , Humanos , Alelos , Teste de Histocompatibilidade/métodos , Antígenos de Histocompatibilidade Classe I/genética , Antígenos HLA/genética , Antígenos
2.
Am J Transplant ; 23(4): 512-519, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36732087

RESUMO

ABO compatibility is important for kidney transplantation, with longer waitlist times for blood group B kidney transplant candidates. However, kidneys from non-A1 (eg, A2) subtype donors, which express less A antigen, can be safely transplanted into group B recipients. ABO subtyping is routinely performed using anti-A1 lectin, but DNA-based genotyping is also possible. Here, we compare lectin and genotyping testing. Lectin and genotype subtyping was performed on 554 group A deceased donor samples at 2 transplant laboratories. The findings were supported by 2 additional data sets of 210 group A living kidney donors and 124 samples with unclear lectin testing sent to a reference laboratory. In deceased donors, genotyping found 65% more A2 donors than lectin testing, most with weak lectin reactivity, a finding supported in living donors and samples sent for reference testing. DNA sequencing and flow cytometry showed that the discordances were because of several factors, including transfusion, small variability in A antigen levels, and rare ABO∗A2.06 and ABO∗A2.16 sequences. Although lectin testing is the current standard for transplantation subtyping, genotyping is accurate and could increase A2 kidney transplant opportunities for group B candidates, a difference that should reduce group B wait times and improve transplant equity.


Assuntos
Transplante de Rim , Humanos , Genótipo , Incompatibilidade de Grupos Sanguíneos , Doadores de Tecidos , Doadores Vivos , Sistema ABO de Grupos Sanguíneos/genética , Isoanticorpos
3.
Am J Transplant ; 21(10): 3239-3255, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34050595

RESUMO

Sex-specific influences have been shown for a variety of diseases. Whether donor or recipient sex and sex hormone levels impact alloimmune responses remains unclear. In unifactorial and multifactorial analyses of more than 400 000 SRTR listed kidney transplant patients, we found that younger female recipients had an inferior death-censored graft survival that was independent of donor sex. In contrast, graft survival was superior in older female recipients, suggesting the impact of recipient sex hormones over chromosomal sex mismatches. Those clinical changes were delineated in experimental skin and heart transplant models showing a prolongation of graft survival in ovariectomized young female recipients. In contrast, graft survival was comparable in ovariectomized and naïve old female recipients. Young ovariectomized mice showed reduced amounts and a compromised T cell proliferation. Deprivation of female hormones dampened the production of interferon (IFN)-γ and interleukin (IL)-17+ by CD4+ T cells while augmenting systemic counts of Tregs. Increasing estradiol concentrations in vitro promoted the switch of naïve CD4+ T cells into Th1 cells; high physiological estradiol concentrations dampening Th1 responses, promoted Tregs, and prolonged graft survival. Thus, clinical observations demonstrate age-specific graft survival patterns in female recipients. Estrogen levels, in turn, impact the fate of T cell subsets, providing relevant and novel information on age- and sex-specific alloimmunity.


Assuntos
Sobrevivência de Enxerto , Transplante de Rim , Fatores Etários , Idoso , Animais , Estradiol , Feminino , Rejeição de Enxerto/etiologia , Humanos , Transplante de Rim/efeitos adversos , Masculino , Camundongos , Doadores de Tecidos
4.
Front Immunol ; 12: 790775, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35222353

RESUMO

A subset of T regulatory cells (Tregs), identified by TIRC7 (T cell immune response cDNA 7) expression is designated as Immune Regulatory 1 Cells (IR1 cells). TIRC7 is an immune checkpoint inhibitor, co-localized with the T- cell receptor, HLA-DR and CTLA-4 during T-cell activation, which delivers regulatory signals via binding to its ligand, HLA-DR α2 domain. IR1 cells express FOXP3, and multiple other markers associated with immune suppression. They constitute as much as 10% of Tregs. IR1 cells strongly inhibit proliferation in mixed lymphocyte reactions, where they express high levels of IL-10. Ex vivo expansion of Tregs over 2 weeks in the presence of an agonist TIRC7 antibody disproportionately expands the IR1 Treg subset, while maintaining high expression of suppressive markers including CD39, IL-10, LAP and GARP. Ex vivo expanded IR1 cells are a potent, homogeneous, stable set of suppressor Tregs with the potential to modulate immune dysregulation. The characteristics of IR1 cells suggest a therapeutic advantage over polyclonal Tregs for therapeutic interventions. Early restoration of immune homeostasis using IR1 cells has the potential to fundamentally alter the natural history of conditions characterized by abnormalities in the T regulatory cell compartment.


Assuntos
Interleucina-10 , Linfócitos T Reguladores , Fatores de Transcrição Forkhead/metabolismo , Antígenos HLA-DR/metabolismo , Humanos , Ativação Linfocitária , Receptores de Antígenos de Linfócitos T/metabolismo
5.
J Clin Invest ; 130(9): 4624-4636, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516138

RESUMO

Graft-versus-host disease (GVHD) is a major cause of morbidity and mortality in hematopoietic stem cell transplantation (HSCT). Donor T cells are key mediators in pathogenesis, but a contribution from host T cells has not been explored, as conditioning regimens are believed to deplete host T cells. To evaluate a potential role for host T cells in GVHD, the origin of skin and blood T cells was assessed prospectively in patients after HSCT in the absence of GVHD. While blood contained primarily donor-derived T cells, most T cells in the skin were host derived. We next examined patient skin, colon, and blood during acute GVHD. Host T cells were present in all skin and colon acute GVHD specimens studied, yet were largely absent in blood. We observed acute skin GVHD in the presence of 100% host T cells. Analysis demonstrated that a subset of host T cells in peripheral tissues were proliferating (Ki67+) and producing the proinflammatory cytokines IFN-γ and IL-17 in situ. Comparatively, the majority of antigen-presenting cells (APCs) in tissue in acute GVHD were donor derived, and donor-derived APCs were observed directly adjacent to host T cells. A humanized mouse model demonstrated that host skin-resident T cells could be activated by donor monocytes to generate a GVHD-like dermatitis. Thus, host tissue-resident T cells may play a previously unappreciated pathogenic role in acute GVHD.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Transplante de Células-Tronco Hematopoéticas , Dermatopatias/imunologia , Pele/imunologia , Linfócitos T/imunologia , Adulto , Aloenxertos , Animais , Células Apresentadoras de Antígenos/imunologia , Células Apresentadoras de Antígenos/patologia , Feminino , Doença Enxerto-Hospedeiro/patologia , Humanos , Interferon gama/imunologia , Interleucina-17/imunologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Estudos Prospectivos , Pele/patologia , Dermatopatias/patologia , Linfócitos T/patologia
6.
J Pathol Inform ; 10: 26, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31463162

RESUMO

BACKGROUND: Calculated panel reactive antibody (cPRA) scoring is used to assess whether platelet refractoriness is mediated by human leukocyte antigen (HLA) antibodies in the recipient. cPRA testing uses a national sample of US kidney donors to estimate the population frequency of HLA antigens, which may be different than HLA frequencies within local platelet inventories. We aimed to determine the impact on patient cPRA scores of using HLA frequencies derived from typing local platelet donations rather than national HLA frequencies. METHODS: We built an open-source web service to calculate cPRA scores based on national frequencies or custom-derived frequencies. We calculated cPRA scores for every hematopoietic stem cell transplantation (HSCT) patient at our institution based on the United Network for Organ Sharing (UNOS) frequencies and local frequencies. We compared frequencies and correlations between the calculators, segmented by gender. Finally, we put all scores into three buckets (mild, moderate, and high sensitizations) and looked at intergroup movement. RESULTS: 2531 patients that underwent HSCT at our institution had at least 1 antibody and were included in the analysis. Overall, the difference in medians between each group's UNOS cPRA and local cPRA was statistically significant, but highly correlated (UNOS vs. local total: 0.249 and 0.243, ρ = 0.994; UNOS vs. local female: 0.474 and 0.463, ρ = 0.987, UNOS vs. local male: 0.165 and 0.141, ρ = 0.996; P < 0.001 for all comparisons). The median difference between UNOS and cPRA scores for all patients was low (male: 0.014, interquartile range [IQR]: 0.004-0.029; female: 0.0013, IQR: 0.003-0.028). Placement of patients into three groups revealed little intergroup movement, with 2.96% (75/2531) of patients differentially classified. CONCLUSIONS: cPRA scores using local frequencies were modestly but significantly different than those obtained using national HLA frequencies. We released our software as open source, so other groups can calculate cPRA scores from national or custom-derived frequencies. Further investigation is needed to determine whether a local-HLA frequency approach can improve outcomes in patients who are immune-refractory to platelets.

8.
Transplant Direct ; 5(5): e446, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31165081

RESUMO

BACKGROUND: Many kidney transplant centers in the United States report both HLA class I and II antibodies detected by sensitive solid-phase assays (SPAs) to United Network for Organ Sharing as unacceptable antigens, significantly reducing the compatible donor organ pool and prolonging waiting time for highly sensitized patients. However, the clinical relevance of all detected donor-specific antibodies (DSAs) by SPA is not unequivocal, because fluorescence intensity does not always accurately reflect antibody pathogenicity. Our center does not exclude patients from transplantation based on DSA class II. METHODS: We performed a retrospective analysis in 179 deceased-donor kidney transplant recipients with solely DSA class II before transplant and patients without DSA and compared graft survival, rejection, and clinical outcomes. Patient survival was also compared with matched controls on the waiting list. RESULTS: Patients transplanted with DSA class II showed a clear survival benefit compared with matched patients who remained on dialysis or were waitlisted on dialysis/transplanted at 5 years (100%, 34%, and 73%, respectively). After a mean follow-up of 5.5 years, there was no significant difference in death-censored graft survival between transplanted patients without DSA and those with preformed DSA class II (adjusted HR 1.10; 95% confidence interval, 0.41-2.97), although the incidence of rejection was higher in recipients with DSA class II (adjusted HR 5.84; 95% confidence interval, 2.58-13.23; P < 0.001). Serum creatinine levels at 1, 3, and 5 years posttransplant did not differ between groups. No predictors of rejection were found, although patients who received basiliximab induction therapy had higher incidence of rejection (100%) compared with those who received antithymocyte globulin (52%). CONCLUSIONS: We conclude that for highly sensitized patients, deceased-donor kidney transplantation with DSA class II yields a survival benefit over prolonged waiting time on dialysis. Instead of listing DSA class II as unacceptable antigens, an individual approach with further immunologic risk assessment is recommended.

9.
Am J Transplant ; 18(7): 1604-1614, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29603613

RESUMO

The presence of preexisting (memory) or de novo donor-specific HLA antibodies (DSAs) is a known barrier to successful long-term organ transplantation. Yet, despite the fact that laboratory tools and our understanding of histocompatibility have advanced significantly in recent years, the criteria to define presence of a DSA and assign a level of risk for a given DSA vary markedly between centers. A collaborative effort between the American Society for Histocompatibility and Immunogenetics and the American Society of Transplantation provided the logistical support for generating a dedicated multidisciplinary working group, which included experts in histocompatibility as well as kidney, liver, heart, and lung transplantation. The goals were to perform a critical review of biologically driven, state-of-the-art, clinical diagnostics literature and to provide clinical practice recommendations based on expert assessment of quality and strength of evidence. The results of the Sensitization in Transplantation: Assessment of Risk (STAR) meeting are summarized here, providing recommendations on the definition and utilization of HLA diagnostic testing, and a framework for clinical assessment of risk for a memory or a primary alloimmune response. The definitions, recommendations, risk framework, and highlighted gaps in knowledge are intended to spur research that will inform the next STAR Working Group meeting in 2019.


Assuntos
Sobrevivência de Enxerto/imunologia , Antígenos HLA/imunologia , Histocompatibilidade/imunologia , Isoanticorpos/imunologia , Transplante de Órgãos , Guias de Prática Clínica como Assunto/normas , Medição de Risco/métodos , Doadores de Tecidos , Humanos , Relatório de Pesquisa
10.
Transplantation ; 102(7): 1188-1194, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29346257

RESUMO

BACKGROUND: Kidney transplantation holds much promise as a treatment of choice for patients with end-stage kidney disease. The impact of cold ischemia time (CIT) on acute renal transplant rejection (ARTR) remains to be fully studied in a large cohort of renal transplant patients. METHODS: From the Organ Procurement and Transplantation Network database, we analyzed 63 798 deceased donor renal transplants performed between 2000 and 2010. We assessed the association between CIT and ARTR. We also evaluated the association between recipient age and ARTR. RESULTS: Six thousand eight hundred two (11%) patients were clinically diagnosed with ARTR. Longer CIT was associated with an increased risk of ARTR. After multivariable adjustment, compared with recipients with CIT < 12 hours, the relative risk of ARTR was 1.13 (95% confidence interval, 1.04-1.23) in recipients with CIT ≥ 24 hours. The association of CIT and ARTR was more pronounced in patients undergoing retransplantation: compared with recipients with CIT less than 12 hours, the relative risk of ARTR was 1.66 (95% confidence interval, 1.01-2.73) in recipients with CIT of 24 hours or longer. Additionally, older age was associated with a decreased risk of ARTR. Compared with recipients aged 18 to 29 years, the relative risk of ARTR was 0.50 (95% confidence interval, 0.45-0.57) in recipients 60 years or older. Longer CIT was also associated with increased risk of death-censored graft loss. Compared with recipients with CIT less than 12 hours, the hazard ratio of death-censored graft loss was 1.22 (95% confidence interval, 1.14-1.30) in recipients with CIT of 24 hours or longer. CONCLUSIONS: Prolonged CIT is associated with an increased risk of ARTR and death-censored graft loss. Older age was associated with a lower risk of ARTR.


Assuntos
Isquemia Fria/efeitos adversos , Rejeição de Enxerto/epidemiologia , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Coleta de Tecidos e Órgãos/efeitos adversos , Adulto , Fatores Etários , Estudos de Coortes , Feminino , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto , Humanos , Transplante de Rim/métodos , Masculino , Pessoa de Meia-Idade , Sistema de Registros/estatística & dados numéricos , Fatores de Tempo , Coleta de Tecidos e Órgãos/métodos , Resultado do Tratamento , Estados Unidos/epidemiologia , Adulto Jovem
11.
BMC Res Notes ; 10(1): 523, 2017 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-29084580

RESUMO

BACKGROUND: The prevalence of chronic kidney disease (CKD) in rural Vietnam is unknown. We wished to determine the prevalence of CKD and determine whether a simple questionnaire was able to detect individuals at high risk of CKD before expensive confirmatory laboratory testing. METHODS: A cross sectional study was performed. We recruited 2037 participants from 13 communes of Long An province, Vietnam, for CKD screening with urine albumin/creatinine ratio (ACR) measured by immunoturbidimetric method and serum creatinine to estimate glomerular filtration rate (eGFR). CKD was defined as either ACR ≥ 30 mg/g or eGFR MDRD < 60 ml/min/1.73 m2. A two page questionnaire with 23 variables was administered to each participant with queries postulated to be correlated with risk of CKD. RESULTS: Of the 2037 participants, 260 (12.76%) were found to have CKD. Five questionnaire variables (age more than 50, measured hypertension, history of diabetes, history of hypertension, and history of a low salt diet) were correlated with CKD, and used to construct a risk score for CKD. CONCLUSIONS: CKD is common in Vietnam. Our questionnaire and risk score tool can be used to detect individuals with a higher likelihood of CKD, and who can then be more economically screened with routine laboratory confirmatory tests.


Assuntos
Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/epidemiologia , Medição de Risco/métodos , Inquéritos e Questionários/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Vietnã/epidemiologia , Adulto Jovem
12.
Transplantation ; 101(9): 2207-2212, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-27893614

RESUMO

BACKGROUND: Development of donor-specific antibodies (DSA) after lung transplantation is associated with antibody mediated rejection, acute cellular rejection, and bronchiolitis obliterans syndrome; however, the significance of circulating antibodies before transplant remains unclear. METHODS: We performed a retrospective cohort study including recipients of primary lung transplants between 2008 and 2012. We assessed the impact of circulating HLA and noncytotoxic DSA detected before transplant on development of Chronic Lung Allograft Dysfunction (CLAD) or CLAD-related death. RESULTS: 30% of subjects had circulating class I antibodies alone, 4% Class II, and 14.4% class I and class II at mean fluorescent intensity greater than 1000. Nine percent of the subjects had DSA class I, 9% class II, and 2.4% both DSA classes 1 and 2. Neither the presence of circulating antibodies (adjusted hazard ratio, 0.87; 95% confidence interval, 0.50-1.54) nor the presence of DSA (adjusted hazard ratio, 1.56; 95% confidence interval, 0.77-3.18) before transplant at mean fluorescent intensity greater than 1000 was associated with the development of CLAD or CLAD-related death. CONCLUSIONS: Although in previous studies we have shown an increased incidence of antibody-mediated rejection in patients with pretransplant DSA, neither the presence of HLA antibodies nor DSA translated to an increased risk of allograft dysfunction or death if prospective crossmatch testing was negative. Prospective studies are needed to define the impact of pretransplant sensitization on lung transplant recipients.


Assuntos
Antígenos HLA/imunologia , Histocompatibilidade , Isoanticorpos/imunologia , Pneumopatias/imunologia , Transplante de Pulmão/efeitos adversos , Adulto , Idoso , Aloenxertos , Doença Crônica , Feminino , Teste de Histocompatibilidade , Humanos , Isoanticorpos/sangue , Pneumopatias/sangue , Pneumopatias/diagnóstico , Transplante de Pulmão/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
14.
Hum Immunol ; 77(12): 1128-1139, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27664843

RESUMO

HLA matching and avoidance of pre-transplant donor-specific antibodies are important in selection of donors for solid organ transplant. Solid phase testing with single antigen beads allows resolution of antibody reactivity to the level of the allele. Single antigen bead testing results at a large transplant center were reviewed to identify selective reactivity patterns of anti-HLA antibodies. Many HLA-DP antibodies were identified in the context of other HLA antibodies, but some sera had antibodies against only HLA-DP. B cell flow crossmatch testing was positive for 2 out of 9 sera with HLA-DP antibodies. Many patterns of reactivity corresponded to epitopes in hypervariable regions C and F of DPB1, but some matched epitopes in other regions or DPA1. Through analysis of single antigen bead testing from a large number of patients, we report that anti-HLA-DP antibodies predominantly recognize broadly cross-reactive epitopes. The United Network for Organ Sharing has mandated HLA-DP typing on all deceased kidney donors, and HLA-DP epitopes should be considered as the major antigens for avoidance of pre-transplant donor-specific antibodies.


Assuntos
Epitopos de Linfócito B/metabolismo , Rejeição de Enxerto/prevenção & controle , Cadeias beta de HLA-DP/metabolismo , Teste de Histocompatibilidade , Transplante de Rim , Alelos , Anticorpos/sangue , Citotoxicidade Celular Dependente de Anticorpos , Reações Cruzadas , Epitopos de Linfócito B/imunologia , Rejeição de Enxerto/imunologia , Cadeias beta de HLA-DP/imunologia , Humanos , Separação Imunomagnética , Doadores de Tecidos
15.
PLoS One ; 11(9): e0162409, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27589328

RESUMO

BACKGROUND: Patients with short telomere syndromes and pulmonary fibrosis have increased complications after lung transplant. However, the more general impact of donor and recipient telomere length in lung transplant has not been well characterized. METHODS: This was an observational cohort study of patients who received lung transplant at a single center between January 1st 2012 and January 31st 2015. Relative donor lymphocyte telomere length was measured and classified into long (third tertile) and short (other tertiles). Relative recipient lung telomere length was measured and classified into short (first tertile) and long (other tertiles). Outcome data included survival, need for modification of immunosuppression, liver or kidney injury, cytomegalovirus reactivation, and acute rejection. RESULTS: Recipient lung tissue telomere lengths were measured for 54 of the 79 patients (68.3%) who underwent transplant during the study period. Donor lymphocyte telomeres were measured for 45 (83.3%) of these recipients. Neither long donor telomere length (hazard ratio [HR] = 0.58, 95% confidence interval [CI], 0.12-2.85, p = 0.50) nor short recipient telomere length (HR = 1.01, 95% CI = 0.50-2.05, p = 0.96) were associated with adjusted survival following lung transplant. Recipients with short telomeres were less likely to have acute cellular rejection (23.5% vs. 58.8%, p = 0.02) but were not more likely to have other organ dysfunction. CONCLUSIONS: In this small cohort, neither long donor lymphocyte telomeres nor short recipient lung tissue telomeres were associated with adjusted survival after lung transplantation. Larger studies are needed to confirm these findings.


Assuntos
Transplante de Pulmão , Telômero , Doadores de Tecidos , Transplantados , Resultado do Tratamento , Adulto , Idoso , Feminino , Rejeição de Enxerto/genética , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Encurtamento do Telômero/genética , Adulto Jovem
16.
Mil Med ; 181(5 Suppl): 221-6, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27168576

RESUMO

Face transplantation was performed in a highly sensitized recipient with positive preoperative crossmatch and subsequent antibody-mediated rejection. The recipient was a 45-year-old female with extensive conventional reconstructions after chemical burns over the majority of the body. Residual quality of life and facial functions were poor. Levels of circulating anti-human leukocyte antigen (HLA) antibodies were high, and panel reactive antibody score was 98%. A potential donor was identified; however, with positive T and B cell flow crossmatches. The transplant team proceeded with face transplantation from this donor, under tailored immune suppression and with available salvage options. The operation was successful. Plasmapheresis and induction immune suppression (i.e., thymoglobulin followed by mycophenolate mofetil, tacrolimus, and steroids) were provided. Five days later, there was significant facial swelling, rising anti-HLA antibody titers, and unprecedented evidence of C4d deposits on skin. High doses of steroids and thymoglobulin were provided; however, rejection increased such that by day 19 it was diagnosed grade III in the BANFF scale. After stopping thymoglobulin because of serum sickness, combination therapy of plasmapheresis, eculizumab, bortezomib, and alemtuzumab was provided. HLA antibody levels decreased while swelling and redness improved. At 3 months, there were no longer signs of rejection on biopsy.


Assuntos
Transplante de Face/métodos , Rejeição de Enxerto/imunologia , Teste de Histocompatibilidade/métodos , Feminino , Antígenos HLA , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Pessoa de Meia-Idade
17.
Biol Blood Marrow Transplant ; 22(1): 27-36, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26348892

RESUMO

Despite stringent procedures to secure the best HLA matching between donors and recipients, life-threatening complications continue to occur after hematopoietic stem cell transplantation (HSCT). Studying single nucleotide polymorphism (SNP) in genes encoding costimulatory molecules could help identify patients at risk for post-HSCT complications. In a stepwise approach we selected SNPs in key costimulatory molecules including CD274, CD40, CD154, CD28, and TNFSF4 and systematically analyzed their association with post-HSCT outcomes. Our discovery cohort analysis of 1157 HLA-A, -B, -C, -DRB1, and -DQB1 matched cases found that patients with donors homozygous for the C variant of rs10912564 in TNFSF4 (48%) had better disease-free survival (P = .029) and overall survival (P = .009) with less treatment-related mortality (P = .006). Our data demonstrate the TNFSF4C variant had a higher affinity for the nuclear transcription factor Myb and increased percentage of TNFSF4-positive B cells after stimulation compared with CT or TT genotypes. However, these associations were not validated in a more recent cohort, potentially because of changes in standard of practice or absence of a true association. Given the discovery cohort, functional data, and importance of TNFSF4 in infection clearance, TNFSF4C may associate with outcomes and warrants future studies.


Assuntos
Neoplasias Hematológicas/genética , Transplante de Células-Tronco Hematopoéticas , Homozigoto , Ligante OX40/genética , Adolescente , Adulto , Idoso , Antígenos CD , Linfócitos B , Estudos de Casos e Controles , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Antígenos HLA/genética , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/patologia , Neoplasias Hematológicas/terapia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Proteínas Oncogênicas v-myb/genética , Polimorfismo de Nucleotídeo Único , Taxa de Sobrevida
18.
Blood ; 125(25): 3886-95, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-25833964

RESUMO

Mice reconstituted with a human immune system provide a tractable in vivo model to assess human immune cell function. To date, reconstitution of murine strains with human hematopoietic stem cells (HSCs) from patients with monogenic immune disorders have not been reported. One obstacle precluding the development of immune-disease specific "humanized" mice is that optimal adaptive immune responses in current strains have required implantation of autologous human thymic tissue. To address this issue, we developed a mouse strain that lacks murine major histocompatibility complex class II (MHC II) and instead expresses human leukocyte antigen DR1 (HLA-DR1). These mice displayed improved adaptive immune responses when reconstituted with human HSCs including enhanced T-cell reconstitution, delayed-type hypersensitivity responses, and class-switch recombination. Following immune reconstitution of this novel strain with HSCs from a patient with immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome, associated with aberrant FOXP3 function, mice developed a lethal inflammatory disorder with multiorgan involvement and autoantibody production mimicking the pathology seen in affected humans. This humanized mouse model permits in vivo evaluation of immune responses associated with genetically altered HSCs, including primary immunodeficiencies, and should facilitate the study of human immune pathobiology and the development of targeted therapeutics.


Assuntos
Autoimunidade/imunologia , Modelos Animais de Doenças , Fatores de Transcrição Forkhead/imunologia , Síndromes de Imunodeficiência/imunologia , Animais , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Fatores de Transcrição Forkhead/deficiência , Fatores de Transcrição Forkhead/genética , Transplante de Células-Tronco Hematopoéticas , Humanos , Imuno-Histoquímica , Imunofenotipagem , Camundongos , Camundongos Knockout , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo
19.
Front Immunol ; 5: 597, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25505899

RESUMO

Human leukocyte antigens (HLA) are important biomarkers because multiple diseases, drug toxicity, and vaccine responses reveal strong HLA associations. Current clinical HLA typing is an elimination process requiring serial testing. We present an alternative in situ synthesized DNA-based microarray method that contains hundreds of thousands of probes representing a complete overlapping set covering 1,610 clinically relevant HLA class I alleles accompanied by computational tools for assigning HLA type to 4-digit resolution. Our proof-of-concept experiment included 21 blood samples, 18 cell lines, and multiple controls. The method is accurate, robust, and amenable to automation. Typing errors were restricted to homozygous samples or those with very closely related alleles from the same locus, but readily resolved by targeted DNA sequencing validation of flagged samples. High-throughput HLA typing technologies that are effective, yet inexpensive, can be used to analyze the world's populations, benefiting both global public health and personalized health care.

20.
Biol Blood Marrow Transplant ; 20(10): 1516-21, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24907627

RESUMO

The impact of early donor cell chimerism on outcomes of T cell-replete reduced-intensity conditioning (RIC) hematopoietic stem cell transplantation (HSCT) is ill defined. We evaluated day 30 (D30) and 100 (D100) total donor cell chimerism after RIC HSCT undertaken between 2002 and 2010 at our institution, excluding patients who died or relapsed before D30. When available, donor T cell chimerism was also assessed. The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), relapse, and nonrelapse mortality (NRM). We evaluated 688 patients with hematologic malignancies (48% myeloid and 52% lymphoid) and a median age of 57 years (range, 18 to 74) undergoing RIC HSCT with T cell-replete donor grafts (97% peripheral blood; 92% HLA-matched), with a median follow-up of 58.2 months (range, 12.6 to 120.7). In multivariable analysis, total donor cell and T cell chimerism at D30 and D100 each predicted RIC HSCT outcomes, with D100 total donor cell chimerism most predictive. D100 total donor cell chimerism <90% was associated with increased relapse (hazard ratio [HR], 2.54; 95% confidence interval [CI], 1.83 to 3.51; P < .0001), impaired PFS (HR, 2.01; 95% CI, 1.53 to 2.65; P < .0001), and worse OS (HR, 1.50; 95% CI, 1.11 to 2.04, P = .009), but not with NRM (HR, .76; 95% CI, .44 to 2.27; P = .33). There was no additional utility of incorporating sustained D30 to D100 total donor cell chimerism or T cell chimerism. Low donor chimerism early after RIC HSCT is an independent risk factor for relapse and impaired survival. Donor chimerism assessment early after RIC HSCT can prognosticate for long-term outcomes and help identify high-risk patient cohorts who may benefit from additional therapeutic interventions.


Assuntos
Neoplasias Hematológicas/terapia , Transplante de Células-Tronco Hematopoéticas , Linfócitos T/imunologia , Quimeras de Transplante/imunologia , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Idoso , Feminino , Sobrevivência de Enxerto , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/imunologia , Neoplasias Hematológicas/mortalidade , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Agonistas Mieloablativos/uso terapêutico , Prognóstico , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Linfócitos T/patologia , Doadores de Tecidos , Quimeras de Transplante/genética , Transplante Homólogo
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