RESUMO
The symptoms and sequelae of sickle cell anaemia (SCA) are caused by the polymerization of deoxygenated sickle haemoglobin, and people with SCA may be uniquely susceptible to adverse outcomes from hypoxia and haemoglobin desaturation. We examined by oximetry adults (aged 18-45 years) with SCA presenting symptoms indicative of polysomnography, at a single institution, irrespective of treatment, for nocturnal hypoxaemia. Clinical labs and blood for in vitro assessments were taken upon enrolment and after 8-12 weeks of oxygen therapy or observation. Of 21 screened participants, nine (43%) had sufficient nocturnal hypoxaemia to warrant oxygen therapy (≥5 min at SpO2 ≤ 88%). Time spent at SpO2 ≤ 88% associated with age (p = 0.0092), annual hospitalizations (p = 0.0018) and anaemia (p = 0.0139), as well as plasma levels of TNFα (p = 0.0019) and IL-4 (p = 0.0147). Longitudinal analysis showed that WBC significantly decreased during the follow-up period in hypoxic individuals but not in non-hypoxic individuals (p = 0.0361 and p = 0.6969 respectively). Plasma levels of CCL2 and IL-1ra tended to increase, while levels of red blood cell reactive oxygen species tended to decrease with oxygen therapy. Overall, nocturnal hypoxaemia was common in this pilot study population and associated with plausible clinical comorbidities; oxygen therapy may decrease inflammation and oxidative damage in hypoxic individuals.
Assuntos
Anemia Falciforme , Hipóxia , Adulto , Humanos , Hipóxia/etiologia , Hipóxia/diagnóstico , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Oximetria , Hemoglobinas/análise , OxigênioRESUMO
Clinical and laboratory correlates of chronic kidney disease (CKD) in sickle cell anaemia remain incompletely defined. In a multicenter cohort study, we evaluated the prevalence of persistent albuminuria (PA) and characteristics associated with PA, albumin-creatinine ratio (ACR) and decreased estimated glomerular filtration rate (eGFR) using logistic, linear and multinomial regression models, respectively. Of 269 participants (median age: 30 years; 57.2% females), the prevalence of PA was 35.7%. Using baseline ACR values of <100 and ≥100 mg/g, the probabilities of PA were 30.0% and 94.6%, respectively. In multivariable logistic regression analyses, male sex (ß = 0.80 [SE = 0.36], p = 0.024) and ACE inhibitors/ARBs use (ß = 1.54 [SE = 0.43], p < 0.001) were associated with higher likelihoods of PA, while higher haemoglobin (ß = -0.33 [SE = 0.13], p = 0.009) and HbF (ß = -0.04 [SE = 0.02], p = 0.041) were associated with lower likelihoods of PA. In multivariable multinomial regression analyses, older age (ß = 0.06 [SE = 0.02], p = 0.004) and higher alkaline phosphatase (ß = 0.01 [SE = 0.00], p = 0.004) were associated with higher odds of having eGFR 60-90 versus eGFR>90 mL/min/1.73 m2 using the cystatin C-based CKD-EPI-2012 equation. Additionally, higher systolic blood pressure (ß = 0.11 [SE = 0.03], p = 0.001) and blood urea nitrogen (ß = 0.45 [SE = 0.12], p < 0.001) were associated with higher odds, while higher haemoglobin (ß = -1.22 [SE = 0.43], p = 0.004) was associated with lower odds of having eGFR<60 versus eGFR>90 mL/min/1.73 m2. PA and decreased eGFR are associated with measures of disease severity and comorbid conditions (Clinicaltrials.gov Identifier: NCT03277547).
RESUMO
INTRODUCTION: The contribution of coagulation activation to the pathogenesis of sickle cell disease (SCD) remains incompletely defined. We evaluated the efficacy and safety of rivaroxaban, an oral direct factor Xa inhibitor, in subjects with sickle cell anemia. MATERIALS AND METHODS: In this pilot, single-center, randomized, double-blind, placebo-controlled, crossover study, eligible subjects with sickle cell anemia received rivaroxaban or placebo. The effect of rivaroxaban on coagulation activation, endothelial activation, inflammation, and microvascular blood flow was evaluated. RESULTS: Fourteen patients (HbSS - 14; females - 9) with mean age of 38 ± 10.6 years were randomized to receive rivaroxaban 20 mg daily or placebo for 4 weeks and, following a 2-week washout phase, were "crossed-over" to the treatment arm opposite to which they were initially assigned. Mean adherence to treatment with rivaroxaban, assessed by pill counts, was 85.6% in the first treatment period and 93.6% in the second period. Treatment with rivaroxaban resulted in a decrease from baseline of thrombin-antithrombin complex versus placebo (-34.4 ug/L [95% CI: -69.4, 0.53] vs. 0.35 ug/L [95% CI: -3.8, 4.5], p = .08), but the difference was not statistically significant. No significant differences were observed in changes from baseline of D-dimer, inflammatory, and endothelial activation markers or measures of microvascular blood flow. Rivaroxaban was well tolerated. CONCLUSIONS: Rivaroxaban was safe but did not significantly decrease coagulation activation, endothelial activation, or inflammation. Rivaroxaban did not improve microvascular blood flow. Adequately powered studies are required to further evaluate the efficacy of rivaroxaban in SCD. Clinicaltrials.gov Identifier: NCT02072668.
Assuntos
Anemia Falciforme/tratamento farmacológico , Coagulação Sanguínea/efeitos dos fármacos , Inibidores do Fator Xa/uso terapêutico , Rivaroxabana/uso terapêutico , Adulto , Anemia Falciforme/sangue , Estudos Cross-Over , Método Duplo-Cego , Inibidores do Fator Xa/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Rivaroxabana/efeitos adversos , Resultado do TratamentoAssuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Hidroxiureia/uso terapêutico , Adulto , Anemia Falciforme/sangue , Anemia Falciforme/patologia , Antidrepanocíticos/farmacologia , Endotélio/efeitos dos fármacos , Endotélio/patologia , Feminino , Humanos , Hidroxiureia/farmacologia , Estudos Longitudinais , Masculino , Pessoa de Meia-IdadeAssuntos
Albuminúria/tratamento farmacológico , Anemia Falciforme/fisiopatologia , Atorvastatina/farmacologia , Endotélio Vascular/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Circulação Renal/efeitos dos fármacos , Insuficiência Renal Crônica/tratamento farmacológico , Idoso , Albuminúria/etiologia , Albuminúria/fisiopatologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Atorvastatina/uso terapêutico , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Hidroxiureia/uso terapêutico , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/urina , Traço Falciforme/complicações , Traço Falciforme/fisiopatologia , Talassemia beta/complicações , Talassemia beta/genética , Talassemia beta/fisiopatologiaRESUMO
Human natural regulatory T cells (nTregs) show great promise for therapeutically modulating immune-mediated disease, but remain poorly understood. One explanation under intense scrutiny is how to induce suppressive function in non-nTregs and increase the size of the regulatory population. A second possibility would be to make existing nTregs more effective, like a catalyst raises the specific activity of an enzyme. The latter has been difficult to investigate due to the lack of a robust short-term suppression assay. Using a microassay described herein we demonstrate that nTregs in distinct phases of cell cycle progression exhibit graded degrees of potency. Moreover, we show that physiological concentrations of 1α,25-dihydroxyvitamin D3 (vitamin D3) boosts nTregs function. The enhanced suppressive capacity is likely due to vitamin D3's ability to uniquely modulate cell cycle progression and elevate FOXP3 expression. These data suggest a role for vitamin D3 as a mechanism for catalyzing potency of nTregs.
Assuntos
Ciclo Celular/efeitos dos fármacos , Colecalciferol/farmacologia , Fatores de Transcrição Forkhead/biossíntese , Linfócitos T Reguladores/efeitos dos fármacos , Ciclo Celular/imunologia , Células Cultivadas , Fatores de Transcrição Forkhead/imunologia , Humanos , Linfócitos T Reguladores/imunologiaRESUMO
FOXP3 is critical for the development and function of CD4(+)CD25(bright) natural regulatory T cells (nTreg). Individuals harboring mutations in FOXP3 develop immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome (IPEX). We describe a child diagnosed with IPEX who underwent a reduced intensity, T and B cell depleted, matched unrelated donor bone marrow transplant followed by clinical resolution. Using lineage-specific donor chimerism studies, we demonstrate that non-myeloablative HSCT resolves disease in the context of low level donor hematopoietic stem cell (HSC) engraftment. Despite low-levels of donor HSC, thymically-derived nTreg and to a lesser extent CD4(+) and CD8(+) T cells, exhibit a selective in vivo growth advantage for populations containing a functional FOXP3 gene. Moreover, nTreg from this patient show regulatory function directly ex vivo. These results have implications for improving clinical therapy for patients with IPEX and provide mechanistic insight into the in vivo development of human nTreg and unexpectedly, non-regulatory T cells.
Assuntos
Transplante de Medula Óssea , Fatores de Transcrição Forkhead/deficiência , Doenças Genéticas Ligadas ao Cromossomo X/cirurgia , Síndromes de Imunodeficiência/cirurgia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Timo/imunologia , Condicionamento Pré-Transplante/métodos , Alemtuzumab , Anticorpos Monoclonais Humanizados , Anticorpos Antineoplásicos , Sobrevivência Celular , Fatores de Transcrição Forkhead/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Facilitação Imunológica de Enxerto , Sobrevivência de Enxerto , Humanos , Síndromes de Imunodeficiência/genética , Lactente , Subunidade alfa de Receptor de Interleucina-2/análise , Depleção Linfocítica , Masculino , Melfalan , Mutação Puntual , Subpopulações de Linfócitos T/citologia , Linfócitos T Reguladores/citologia , Tiotepa , Transplante Homólogo , Vidarabina/análogos & derivadosRESUMO
CD4+ CD25+ regulatory T cells have been the subject of intense investigation and have been shown to modulate immune responses in the settings of autoimmunity, cancer and transplantation. The assessment and optimization of purification schemes for specific cellular subtypes such as CD4+ CD25+ regulatory T cells is a critical consideration in developing cell-based therapies in the clinical setting. In the following studies, different strategies for magnetic isolation are compared and the parameters which affect the overall potency of purified human CD4+ CD25+ regulatory T cells are discussed. The data demonstrate that large-scale magnetic isolation can be used to efficiently and reproducibly purify human CD4+ CD25+ regulatory T cells capable of modulating alloreactive T cell responses. The ability to rapidly purify the desired cells from peripheral blood suggests that magnetic isolation may be a suitable alternative to cell sorting for clinical settings, where large numbers of CD4+ CD25+ regulatory T cells may be necessary.
Assuntos
Separação Imunomagnética/métodos , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Linfócitos T Reguladores/fisiologia , Células Cultivadas , Fatores de Transcrição Forkhead/metabolismo , Humanos , Separação Imunomagnética/normas , Reprodutibilidade dos TestesRESUMO
Vector capsid dose-dependent inflammation of transduced liver has limited the ability of adeno-associated virus (AAV) factor IX (FIX) gene therapy vectors to reliably convert severe to mild hemophilia B in human clinical trials. These trials also identified the need to understand AAV neutralizing antibodies and empty AAV capsids regarding their impact on clinical success. To address these safety concerns, we have used a scalable manufacturing process to produce GMP-grade AAV8 expressing the FIXR338L gain-of-function variant with minimal (<10%) empty capsid and have performed comprehensive dose-response, biodistribution, and safety evaluations in clinically relevant hemophilia models. The scAAV8.FIXR338L vector produced greater than 6-fold increased FIX specific activity compared with wild-type FIX and demonstrated linear dose responses from doses that produced 2-500% FIX activity, associated with dose-dependent hemostasis in a tail transection bleeding challenge. More importantly, using a bleeding model that closely mimics the clinical morbidity of hemophilic arthropathy, mice that received the scAAV8.FIXR338L vector developed minimal histopathological findings of synovitis after hemarthrosis, when compared with mice that received identical doses of wild-type FIX vector. Hemostatically normal mice (n=20) and hemophilic mice (n=88) developed no FIX antibodies after peripheral intravenous vector delivery. No CD8(+) T cell liver infiltrates were observed, despite the marked tropism of scAAV8.FIXR338L for the liver in a comprehensive biodistribution evaluation (n=60 animals). With respect to the role of empty capsids, we demonstrated that in vivo FIXR338L expression was not influenced by the presence of empty AAV particles, either in the presence or absence of various titers of AAV8-neutralizing antibodies. Necropsy of FIX(-/-) mice 8-10 months after vector delivery revealed no microvascular or macrovascular thrombosis in mice expressing FIXR338L (plasma FIX activity, 100-500%). These preclinical studies demonstrate a safety:efficacy profile supporting an ongoing phase 1/2 human clinical trial of the scAAV8.FIXR338L vector (designated BAX335).
Assuntos
Dependovirus/genética , Fator IX/genética , Terapia Genética/métodos , Vetores Genéticos/farmacocinética , Hemofilia B/terapia , Hemorragia/prevenção & controle , Animais , Anticorpos Neutralizantes/análise , Capsídeo/química , Capsídeo/imunologia , Ensaios Clínicos como Assunto , Dependovirus/imunologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Fator IX/metabolismo , Fator IX/farmacocinética , Expressão Gênica , Engenharia Genética , Vetores Genéticos/administração & dosagem , Vetores Genéticos/química , Hemofilia B/sangue , Hemofilia B/genética , Hemofilia B/fisiopatologia , Hemorragia/sangue , Hemorragia/genética , Hemorragia/fisiopatologia , Humanos , Fígado/imunologia , Fígado/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacocinética , Cauda , Distribuição Tecidual , Vírion/genéticaRESUMO
PURPOSE: To prospectively determine the prognostic significance of the TEL-AML1 fusion in children with acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: TEL gene status was determined for 926 patients with B-precursor ALL enrolled on the Pediatric Oncology Group ALinC 16 trials and patients were observed for a median time of 8 years. RESULTS: Rearrangements of the TEL gene were detected in 244 patients (26%). The estimated 5-year event-free survival rate (+/- SE) for patients with TEL rearrangements was 86% +/- 2%, compared with 72% +/- 2% for those with germline TEL (P < .0001). TEL rearrangements were associated with a superior outcome among patients with standard-risk ALL, high-risk ALL, and rapid early responses to therapy. In a multivariate analysis that included risk group, sex, and day 15 marrow status, TEL status was an independent predictor of outcome (P = .0002). CONCLUSION: We conclude that TEL gene status should be incorporated into risk classification schemes and suggest that patients who have standard-risk features, the TEL-AML1 fusion, and rapid early responses to therapy, should be treated with antimetabolite-based therapy designed to maintain their high cure rates and avoid late effects.
Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Regulação Leucêmica da Expressão Gênica , Rearranjo Gênico , Proteínas de Fusão Oncogênica/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Adolescente , Adulto , Medula Óssea/patologia , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores Sexuais , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Estados UnidosRESUMO
The restriction of influenza A virus replication to mouse respiratory epithelium means that this host response is anatomically compartmentalized, on the one hand, to sites of T cell stimulation and proliferation in the secondary lymphoid tissue and, on the other hand, to the site of effector T cell function and pathology in the pneumonic lung. Thus, it is hardly surprising that virus-specific CD8(+) T cells recovered by bronchoalveolar lavage (BAL) from the infected respiratory tract seem more "activated" in terms of both cytolytic activity and cytokine production than those cells isolated from the spleen. The present analysis uses Affymetrix microarray technology to compare profiles of gene expression in these two lineage-related, yet anatomically separate, lymphocyte populations. Ninety differentially expressed genes were identified for influenza-specific CD8(+)D(b)NP(366)(+) T cells obtained directly ex vivo by BAL or spleen disruption, with nine genes being further analyzed by quantitative, real-time PCR at the population level. Integrin alphaE, for example, was shown by Affymetrix and real-time mRNA analyses and then by single-cell PCR and protein staining to be present at a much higher prevalence on the BAL CD8(+)D(b)NP(366)(+) set. The unpredicted finding, however, was that mRNA expression for 75% of the 90 genes was lower in T cells from the BAL than from the spleen. Apparently, the localization of virus-specific CD8(+) T cells to the site of virus-induced pathology is associated with a narrowing, or "focusing," of gene expression that favors enhanced effector function in the damaged, "high-antigen load" environment of the pneumonic lung.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Regulação da Expressão Gênica/imunologia , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Infecções por Orthomyxoviridae/imunologia , Animais , Líquido da Lavagem Broncoalveolar/citologia , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/fisiologia , Diferenciação Celular , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência com Séries de Oligonucleotídeos , Infecções por Orthomyxoviridae/genética , Pneumonia Viral/genética , Pneumonia Viral/imunologia , Linfócitos T Citotóxicos/imunologiaRESUMO
CD4(+)CD25(+) T cells are critical mediators of peripheral immune tolerance. However, many developmental and functional characteristics of these cells are unknown, and knowledge of human regulatory T cells is particularly limited. To better understand how human CD4(+)CD25(+) T cells develop and function, we examined the diversity of CD4(+)CD25(+) and CD4(+)CD25(-) T cell repertoires in both thymus and peripheral blood. Levels of T receptor excision circles (TREC) were comparable in purified CD4(+)CD25(+) and CD4(+)CD25(-) thymic populations, but were significantly higher than those in samples derived from peripheral blood, consistent with murine studies demonstrating thymic development of CD4(+)CD25(+) regulatory T cells. Surprisingly, CD4(+)CD25(-) T cells isolated from peripheral blood had greater TREC quantities than their CD4(+)CD25(+) counterparts, supporting the possibility of extrathymic expansion as well. CD4(+)CD25(+) and CD4(+)CD25(-) T cells from a given individual showed overlapping profiles with respect to diversity by Vbeta staining and spectratyping. Interestingly, CD4(+)CD25(+) T cells have lower quantities of CD3 than CD4(+)CD25(-) T cells. Collectively, these data suggest that human CD4(+)CD25(+) T cells recognize a similar array of Ags as CD4(+)CD25(-) T cells. However, reduced levels of TCR on regulatory T cells suggest different requirements for activation and may contribute to how the immune system regulates whether a particular response is suppressed or augmented.