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1.
Nat Immunol ; 15(5): 431-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24658051

RESUMO

CD96, CD226 (DNAM-1) and TIGIT belong to an emerging family of receptors that interact with nectin and nectin-like proteins. CD226 activates natural killer (NK) cell-mediated cytotoxicity, whereas TIGIT reportedly counterbalances CD226. In contrast, the role of CD96, which shares the ligand CD155 with CD226 and TIGIT, has remained unclear. In this study we found that CD96 competed with CD226 for CD155 binding and limited NK cell function by direct inhibition. As a result, Cd96(-/-) mice displayed hyperinflammatory responses to the bacterial product lipopolysaccharide (LPS) and resistance to carcinogenesis and experimental lung metastases. Our data provide the first description, to our knowledge, of the ability of CD96 to negatively control cytokine responses by NK cells. Blocking CD96 may have applications in pathologies in which NK cells are important.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Células Matadoras Naturais/imunologia , Receptores Imunológicos/metabolismo , Animais , Antígenos CD/genética , Antígenos de Diferenciação de Linfócitos T/genética , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Citotoxicidade Imunológica/genética , Lipopolissacarídeos/imunologia , Neoplasias Pulmonares/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nectinas , Metástase Neoplásica , Neoplasias Experimentais/imunologia , Pneumonia/imunologia , Ligação Proteica/genética , Receptores Virais/metabolismo
2.
Blood ; 143(8): 673-684, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-37883795

RESUMO

ABSTRACT: CD19-directed chimeric antigen receptor T cells (CAR-T) achieve high response rates in patients with relapsed/refractory mantle cell lymphoma (MCL). However, their use is associated with significant toxicity, relapse concern, and unclear broad tractability. Preclinical and clinical data support a beneficial synergistic effect of ibrutinib on apheresis product fitness, CAR-T expansion, and toxicity. We evaluated the combination of time-limited ibrutinib and CTL019 CAR-T in 20 patients with MCL in the phase 2 TARMAC study. Ibrutinib commenced before leukapheresis and continued through CAR-T manufacture for a minimum of 6 months after CAR-T administration. The median prior lines of therapy was 2; 50% of patients were previously exposed to a Bruton tyrosine kinase inhibitor (BTKi). The primary end point was 4-month postinfusion complete response (CR) rate, and secondary end points included safety and subgroup analysis based on TP53 aberrancy. The primary end point was met; 80% of patients demonstrated CR, with 70% and 40% demonstrating measurable residual disease negativity by flow cytometry and molecular methods, respectively. At 13-month median follow-up, the estimated 12-month progression-free survival was 75% and overall survival 100%. Fifteen patients (75%) developed cytokine release syndrome; 12 (55%) with grade 1 to 2 and 3 (20%) with grade 3. Reversible grade 1 to 2 neurotoxicity was observed in 2 patients (10%). Efficacy was preserved irrespective of prior BTKi exposure or TP53 mutation. Deep responses correlated with robust CAR-T expansion and a less exhausted baseline T-cell phenotype. Overall, the safety and efficacy of the combination of BTKi and T-cell redirecting immunotherapy appears promising and merits further exploration. This trial was registered at www.ClinicalTrials.gov as #NCT04234061.


Assuntos
Adenina/análogos & derivados , Linfoma de Célula do Manto , Piperidinas , Receptores de Antígenos Quiméricos , Adulto , Humanos , Linfoma de Célula do Manto/tratamento farmacológico , Receptores de Antígenos Quiméricos/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Linfócitos T , Imunoterapia Adotiva/métodos , Antígenos CD19
3.
Blood ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39316646

RESUMO

Pre-transplant detection of KMT2Ar MRD ≥0.001% by quantitative PCR was associated with significantly inferior post-transplant survival (2-year RFS 17% vs 59%; p=0.001) and increased cumulative incidence of relapse (2-year CIR 75% vs 25%, p=0.0004).

4.
Blood ; 144(8): 867-872, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-38662991

RESUMO

ABSTRACT: In the phase 2 clinical trial (AIM) of venetoclax-ibrutinib, 24 patients with mantle cell lymphoma (MCL; 23 with relapsed/refractory [R/R] disease) received ibrutinib 560 mg and venetoclax 400 mg both once daily. High complete remission (CR) and measurable residual disease negative (MRD-negative) CR rates were previously reported. With median survivor follow-up now exceeding 7 years, we report long-term results. Treatment was initially continuous, with elective treatment interruption (ETI) allowed after protocol amendment for patients in MRD-negative CR. For R/R MCL, the estimated 7-year progression-free survival (PFS) was 30% (95% confidence interval [CI], 14-49; median, 28 months; 95% CI, 13-82) and overall survival (OS) was 43% (95% CI, 23-62; median, 32 months; 95% CI, 15 to not evaluable). Eight patients in MRD-negative CR entered ETI for a median of 58 months (95% CI, 37-79), with 4 experiencing disease recurrence. Two of 3 reattained CR on retreatment. Time-to-treatment failure (TTF), which excluded progression in ETI for those reattaining response, was 39% overall and 68% at 7 years for responders. Beyond 56 weeks, grade ≥3 and serious adverse events were uncommon. Newly emergent or increasing cardiovascular toxicity were not observed beyond 56 weeks. We demonstrate long-term durable responses and acceptable toxicity profile of venetoclax-ibrutinib in R/R MCL and show feasibility of treatment interruption while maintaining ongoing disease control. This trial was registered at www.clinicaltrials.gov as #NCT02471391.


Assuntos
Adenina , Protocolos de Quimioterapia Combinada Antineoplásica , Compostos Bicíclicos Heterocíclicos com Pontes , Linfoma de Célula do Manto , Piperidinas , Sulfonamidas , Humanos , Linfoma de Célula do Manto/tratamento farmacológico , Linfoma de Célula do Manto/mortalidade , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico , Sulfonamidas/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes/administração & dosagem , Compostos Bicíclicos Heterocíclicos com Pontes/efeitos adversos , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Adenina/análogos & derivados , Adenina/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Piperidinas/administração & dosagem , Piperidinas/efeitos adversos , Piperidinas/uso terapêutico , Idoso de 80 Anos ou mais , Indução de Remissão , Resultado do Tratamento , Adulto , Seguimentos , Intervalo Livre de Doença
5.
Blood ; 2024 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-39471335

RESUMO

Venetoclax, a first-in-class BH3 mimetic drug targeting BCL-2, has improved outcomes for patients with chronic lymphocytic leukemia (CLL). Early measurements of the depth of the venetoclax treatment response, assessed by minimal residual disease, are strong predictors of long-term clinical outcomes. Yet, there are limited data concerning the early changes induced by venetoclax treatment that might inform strategies to improve responses. To address this gap, we conducted longitudinal mass cytometric profiling of blood cells from patients with CLL during the first five weeks of venetoclax monotherapy. At baseline, we resolved CLL heterogeneity at the single-cell level to define multiple subpopulations in all patients distinguished by proliferative, metabolic and cell survival proteins. Venetoclax induced significant reduction in all CLL subpopulations coincident with rapid upregulation of pro-survival BCL-2, BCL-XL and MCL-1 proteins in surviving cells, which had reduced sensitivity to the drug. Mouse models recapitulated the venetoclax-induced elevation of survival proteins in B cells and CLL-like cells that persisted in vivo, with genetic models demonstrating that extensive apoptosis and access to the B cell cytokine, BAFF, were essential. Accordingly, analysis of patients with CLL that were treated with venetoclax or the anti-CD20 antibody obinutuzumab exhibited marked elevation of BAFF and increased pro-survival proteins in leukemic cells that persisted. Overall, these data highlight the rapid adaptation of CLL cells to targeted therapies via homeostatic factors and support co-targeting of cytokine signals to achieve deeper and more durable long-term responses.

6.
Immunity ; 44(1): 32-45, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26795251

RESUMO

A characteristic of mucosal-associated invariant T (MAIT) cells is the expression of TRAV1-2(+) T cell receptors (TCRs) that are activated by riboflavin metabolite-based antigens (Ag) presented by the MHC-I related molecule, MR1. Whether the MR1-restricted T cell repertoire and associated Ag responsiveness extends beyond these cells remains unclear. Here, we describe MR1 autoreactivity and folate-derivative reactivity in a discrete subset of TRAV1-2(+) MAIT cells. This recognition was attributable to CDR3ß loop-mediated effects within a consensus TRAV1-2(+) TCR-MR1-Ag footprint. Furthermore, we have demonstrated differential folate- and riboflavin-derivative reactivity by a diverse population of "atypical" TRAV1-2(-) MR1-restricted T cells. We have shown that TRAV1-2(-) T cells are phenotypically heterogeneous and largely distinct from TRAV1-2(+) MAIT cells. A TRAV1-2(-) TCR docks more centrally on MR1, thereby adopting a markedly different molecular footprint to the TRAV1-2(+) TCR. Accordingly, diversity within the MR1-restricted T cell repertoire leads to differing MR1-restricted Ag specificity.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Ativação Linfocitária/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T/imunologia , Autoimunidade/imunologia , Cristalografia por Raios X , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe I/química , Humanos , Imunidade nas Mucosas/imunologia , Células Jurkat , Antígenos de Histocompatibilidade Menor , Receptores de Antígenos de Linfócitos T/química , Ressonância de Plasmônio de Superfície
7.
Nano Lett ; 24(9): 2839-2845, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38395430

RESUMO

Semiconductor quantum dots are promising candidates for the generation of nonclassical light. Coupling a quantum dot to a device capable of providing polarization-selective enhancement of optical transitions is highly beneficial for advanced functionalities, such as efficient resonant driving schemes or applications based on optical cyclicity. Here, we demonstrate broadband polarization-selective enhancement by coupling a quantum dot emitting in the telecom O-band to an elliptical bullseye resonator. We report bright single-photon emission with a degree of linear polarization of 96%, Purcell factor of 3.9 ± 0.6, and count rates up to 3 MHz. Furthermore, we present a measurement of two-photon interference without any external polarization filtering. Finally, we demonstrate compatibility with compact Stirling cryocoolers by operating the device at temperatures up to 40 K. These results represent an important step toward practical integration of optimal quantum dot photon sources in deployment-ready setups.

8.
Br J Haematol ; 205(3): 1170-1179, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39021060

RESUMO

Uncertainty remains regarding the safety and tolerability of immunosuppressive therapy (IST) with anti-thymocyte globulin (ATG) and cyclosporine (CSA) in older patients. We retrospectively analysed two prospective clinical trials of IST in treatment-naïve severe aplastic anaemia (SAA) to assess safety in older compared to younger patients. Patients ≥18 years of age who had received IST with ATG and CSA +/- eltrombopag (EPAG) were included. Pre-treatment baseline characteristics and co-morbidities were assessed as predictors of therapy-related complications in younger (<60 years) versus older (≥60 years) patients. Out of 245 eligible patients, 54 were older and 191 were younger. Older patients had a similar frequency of SAEs, ICU admissions and hospital length of stay compared to younger patients. Older patients had a higher frequency of cardiac events related to IST, but none resulted in death. Older patients had worse long-term overall survival, and more relapse and clonal evolution post-IST. However, older patients who responded to IST had a similar survival at a median follow-up to younger patients. Disease-related factors and limited therapeutic options in refractory disease likely contribute to poorer outcomes in older patients, not complications of upfront IST. Therefore, IST should be considered first-line therapy for most older SAA patients.


Assuntos
Anemia Aplástica , Soro Antilinfocitário , Ciclosporina , Hidrazinas , Imunossupressores , Humanos , Anemia Aplástica/tratamento farmacológico , Anemia Aplástica/mortalidade , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Imunossupressores/uso terapêutico , Imunossupressores/efeitos adversos , Ciclosporina/uso terapêutico , Ciclosporina/efeitos adversos , Soro Antilinfocitário/uso terapêutico , Soro Antilinfocitário/efeitos adversos , Estudos Retrospectivos , Adulto , Hidrazinas/uso terapêutico , Hidrazinas/efeitos adversos , Fatores Etários , Pirazóis/uso terapêutico , Pirazóis/efeitos adversos , Benzoatos/uso terapêutico , Benzoatos/efeitos adversos , Resultado do Tratamento , Adulto Jovem , Idoso de 80 Anos ou mais , Adolescente
9.
Cytometry A ; 105(5): 394-403, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38421087

RESUMO

In this study we describe three different methods for labeling T lymphocytes with cell trace violet (CTV), in order to track cell division in mouse and human cells, in both the in vitro and in vivo setting. We identified a modified method of CTV labeling that can be applied directly to either conventional or spectral flow cytometry, that maintained lymphocyte viability and function, yet minimized dye spill-over into other fluorochrome channels. Our optimized method for CTV labeling allowed us to identify up to eight cell divisions and the replication index for in vitro-stimulated mouse and human lymphocytes, and the co-expression of T-cell subset markers. Furthermore, the homeostatic trafficking, expansion and division of CTV-labeled congenic donor T cells could be detected using spectral cytometry, in an adoptive T-cell transfer mouse model. Our optimized CTV method can be applied to both in vitro and in vivo settings to examine the behavior and phenotype of activated T cells.


Assuntos
Proliferação de Células , Sobrevivência Celular , Citometria de Fluxo , Animais , Citometria de Fluxo/métodos , Humanos , Camundongos , Coloração e Rotulagem/métodos , Camundongos Endogâmicos C57BL , Ativação Linfocitária/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Corantes Fluorescentes/química
10.
Calcif Tissue Int ; 114(4): 377-385, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38376757

RESUMO

As outcomes from allogeneic bone marrow transplantation (BMT) have improved, prevention of long-term complications, such as fragility fractures, has gained importance. We aimed to assess areal bone mineral density (aBMD) and trabecular bone score (TBS) changes post BMT, and determine their relationship with fracture prevalence. Patients who attended the Royal Melbourne Hospital (RMH) BMT clinic between 2005-2021 were included. Patient characteristics and dual-energy X-ray absorptiometry (DXA) values were collected from the electronic medical record and a survey. TBS iNsight™ was used to calculate TBS for DXA scans performed from 2019 onwards. 337 patients with sequential DXAs were eligible for inclusion. Patients were primarily male (60%) and mean age ± SD was 45.7 ± 13.4 years. The annualised decline in aBMD was greater at the femoral neck (0.066g/cm2 (0.0038-0.17)) and total hip (0.094g/cm2 (0.013-0.19)), compared to the lumbar spine (0.049g/cm2 (- 0.0032-0.16)), p < 0.0001. TBS declined independently of aBMD T-scores at all sites. Eighteen patients (5.3%) sustained 19 fractures over 3884 person-years of follow-up post-transplant (median follow-up 11 years (8.2-15)). This 5.3% fracture prevalence over the median 11-year follow-up period is higher than what would be predicted with FRAX® estimates. Twenty-two patients (6.5%) received antiresorptive therapy, and 9 of 18 (50%) who fractured received or were on antiresorptive therapy. In BMT patients, aBMD and TBS decline rapidly and independently in the first year post BMT. However, FRAX® fracture probability estimates incorporating these values significantly underestimate fracture rates, and antiresorptive treatment rates remain relatively low.


Assuntos
Densidade Óssea , Fraturas por Osteoporose , Humanos , Masculino , Fraturas por Osteoporose/epidemiologia , Osso Esponjoso , Transplante de Medula Óssea/efeitos adversos , Absorciometria de Fóton , Vértebras Lombares , Colo do Fêmur , Medição de Risco
11.
Ann Hematol ; 103(2): 593-602, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37926752

RESUMO

Infectious diarrhoea is common post-allogeneic haematopoietic stem-cell transplantation (alloHSCT). While the epidemiology of Clostridioides difficile infection (CDI) post-alloHSCT has been described, the impact of other diarrhoeal pathogens is uncertain. We reviewed all alloHSCT between 2017 and 2022 at a single large transplant centre; 374 patients were identified and included. The 1-year incidence of infectious diarrhoea was 23%, divided into viral (13/374, 3%), CDI (65/374, 17%) and other bacterial infections (16/374, 4%). There was a significant association between infectious diarrhoea within 1 year post-transplant and the occurrence of severe acute lower gastrointestinal graft-versus-host disease (GVHD, OR = 4.64, 95% CI 2.57-8.38, p < 0.001) and inferior GVHD-free, relapse-free survival on analysis adjusted for age, donor type, stem cell source and T-cell depletion (aHR = 1.64, 95% CI = 1.18-2.27, p = 0.003). When the classes of infectious diarrhoea were compared to no infection, bacterial (OR = 6.38, 95% CI 1.90-21.40, p = 0.003), CDI (OR = 3.80, 95% CI 1.91-7.53, p < 0.001) and multiple infections (OR = 11.16, 95% CI 2.84-43.92, p < 0.001) were all independently associated with a higher risk of severe GI GVHD. Conversely, viral infections were not (OR = 2.98, 95% CI 0.57-15.43, p = 0.20). Non-viral infectious diarrhoea is significantly associated with the development of GVHD. Research to examine whether the prevention of infectious diarrhoea via infection control measures or modulation of the microbiome reduces the incidence of GVHD is needed.


Assuntos
Infecções por Clostridium , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Transplante Homólogo/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/epidemiologia , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Infecções por Clostridium/etiologia , Diarreia/epidemiologia , Diarreia/etiologia , Estudos Retrospectivos
12.
Cell ; 138(2): 226-8, 2009 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-19632173

RESUMO

Expression of the cell-surface protein CD47 allows some normal cells to avoid phagocytosis by macrophages. In this issue, Jaiswal et al. (2009) and Majeti et al. (2009) show that elevated CD47 expression by leukemic stem cells inhibits macrophage activity and is an indicator of poor prognosis for patients with acute myeloid leukemia.


Assuntos
Antígeno CD47/imunologia , Leucemia Mieloide Aguda/imunologia , Leucemia Mieloide Aguda/terapia , Células-Tronco Neoplásicas/imunologia , Fagocitose , Animais , Humanos , Macrófagos/imunologia , Camundongos
13.
Plant Dis ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587794

RESUMO

In July 2022, dark brown to black, angular, water-soaked lesions were observed on sesame leaves (Sesamum indicum L.) in a research plot established to assess yield potential for eight varieties at the North Carolina (NC) Sandhills Research Station (Chavez 2023). Symptoms were indicative of a bacterial leaf spot (BLS). At early flowering stage, leaf spots were present on scattered plants; varieties ES108, SS3301, and ES201 exhibited up to 75% disease prevalence, with lower frequency in ES103, S39, S4302, S3251, and S3276. Symptomatic leaves from 3-4 plants were collected on four different dates from July through September. A section of symptomatic tissue was excised and macerated in sterile deionized water (SDW). A 10 µL aliquot was streaked onto SPA medium (15 g sucrose, 5.0 g proteose peptone, 0.50 g MgSO4 7H2O, 0.25 g K2HPO4, 15 g agar per liter of SDW) and incubated at 28ºC. After 72 h, numerous, smooth, white-cream colored, convex-shaped, colonies were individually isolated. Five randomly selected isolates from the different collection dates, designated as AHP108-AHP111 and AHP116, were genotyped. The 16S rRNA, gyrB, rpoD, and gapA genes were sequenced (Heuer et al. 1997; Hwang et al. 2005) and deposited to NCBI (GenBank Accessions: P213467- PP213470; OQ628040-OQ628042; PP214983-PP214994; and PP255798). These five isolates shared 100% sequence identity for gyrB and rpoD. AHP108-AHP111 shared 100% sequence identity for 16S rRNA and gapA, with 99.7% and 90.8% identity, respectively, for AHP116. A phylogenetic tree was inferred from a maximum-likelihood analysis of concatenated gyrB, rpoD, and gapA sequences of the five isolates and the top 11 hts from a blastn search of the NCBI nucleotide database. Those hits included closely related sequences from Pseudomonas syringae pv. sesami type strains ICMP 763T and ICMP 7459T. Based on this phylogenetic analysis AHP108-AHP111 and AHP116 are P. syringae pv. sesami. Recent genomic analysis suggests this pathovar is part of P. amygdali (Gomila et al. 2017), but an official name change has not been proposed. Each of the five isolates were infiltrated into leaves of sesame varieties ES108, ES103, and S327, consistently resulting in similar symptoms. Thus, strain AHP116, as a representative, was used to fulfill Koch's postulates using five, 30-day-old potted sesame plants (var. S3301). Plants were spray-inoculated with a bacterial suspension of ~108 CFU/ml until runoff; plants were incubated in moist chambers 24 h pre and post inoculation at 28ºC with 80% relative humidity and a 12 h photoperiod. At 13 days post inoculation, symptoms resembling those on plants at the Sandhills Research Stations in 2022 were evident. Reisolated bacteria were confirmed to be AHP116 through 16S rRNA and gyrB amplification and sequencing. No symptoms were observed on the five water-inoculated plants. BLS of sesame has been reported in Asia and is thought to be seedborne (Firdous et al. 2009; Prathuangwong and Yowabutra 1997). To our knowledge, this is the first report of P. syringae pv. sesami causing BLS on sesame in North Carolina. Sesame cultivation in the state increased from approximately 2,000 acres in 2022 to 13,000 acres in 2023 and there is interest in cultivating sesame as a rotational and alternative crop because it requires minimal input costs. Potential outbreaks of BLS in this warm, humid region could negatively affect sesame production, where little is known about the economic impact of the disease.

14.
Nano Lett ; 23(5): 1705-1710, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36790264

RESUMO

Imposing an external periodic electrostatic potential to the electrons confined in a quantum well makes it possible to engineer synthetic two-dimensional band structures, with electronic properties different from those in the host semiconductor. Here we report the fabrication and study of a tunable triangular artificial lattice on a GaAs/AlGaAs heterostructure where it is possible to transform from the original GaAs band structure and a circular Fermi surface to a new band structure with multiple artificial Fermi surfaces simply by altering a gate bias. For weak electrostatic modulation magnetotransport measurements reveal multiple quantum oscillations and commensurability oscillations due to the electron scattering from the artificial lattice. Increasing the strength of the modulation reveals new commensurability oscillations of the electrons from the artificial Fermi surface scattering from the triangular artificial lattice. These results show that low disorder gate-tunable lateral superlattices can be used to form artificial two-dimensional crystals with designer electronic properties.

15.
Blood ; 137(14): 1970-1979, 2021 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-33512442

RESUMO

We determined the efficacy of tocilizumab (TCZ) in preventing grade 2-4 acute graft-versus-host disease (aGVHD) in patients with acute leukemia or myelodysplasia undergoing matched sibling donor (MSD) or volunteer unrelated donor (VUD) allogeneic stem cell transplantation after myeloablative or reduced-intensity conditioning across 5 Australian centers. A total of 145 patients (50 MSD, 95 VUD) were randomly assigned to placebo or TCZ on day -1. All patients received T-cell-replete peripheral blood stem cell grafts and graft-versus-host disease (GVHD) prophylaxis with cyclosporin/methotrexate. A planned substudy analyzed the VUD cohort. With a median follow-up of 746 days, the incidence of grade 2-4 aGVHD at day 100 for the entire cohort was 36% for placebo vs 27% for TCZ (hazard ratio [HR], 0.69; 95% confidence interval [CI], 0.38-1.26; P = .23) and 45% vs 32% (HR, 0.61; 95% CI, 0.31-1.22; P = .16) for the VUD subgroup. The incidence of grade 2-4 aGVHD at day 180 for the entire cohort was 40% for placebo vs 29% for TCZ (HR, 0.68; 95% CI, 0.38-1.22; P = .19) and 48% vs 32% (HR, 0.59; 95% CI, 0.30-1.16; P = .13) for the VUD subgroup. Reductions in aGVHD were predominantly in grade 2 disease. For the entire cohort, transplant-related mortality occurred in 8% vs 11% of placebo-treated vs TCZ-treated patients, respectively (P = .56), and overall survival was 79% vs 71% (P = .27). Median day to neutrophil and platelet engraftment was delayed by 2 to 3 days in TCZ-treated patients, whereas liver toxicity and infectious complications were similar between groups. In this phase 3 randomized double-blind trial, TCZ showed nonsignificant trends toward reduced incidence of grade 2-4 aGVHD in recipients from HLA-matched VUDs but no improvements in long term-survival.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Ciclosporina/uso terapêutico , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas , Imunossupressores/uso terapêutico , Metotrexato/uso terapêutico , Adulto , Método Duplo-Cego , Feminino , Humanos , Leucemia/terapia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/terapia , Efeito Placebo , Transplante Homólogo , Resultado do Tratamento
16.
Haematologica ; 108(1): 83-97, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35770527

RESUMO

Patients with refractory relapsed multiple myeloma respond to combination treatment with elotuzumab and lenalidomide. The mechanisms underlying this observation are not fully understood. Furthermore, biomarkers predictive of response have not been identified to date. To address these issues, we used a humanized myeloma mouse model and adoptive transfer of human natural killer (NK) cells to show that elotuzumab and lenalidomide treatment controlled myeloma growth, and this was mediated through CD16 on NK cells. In co-culture studies, we showed that peripheral blood mononuclear cells from a subset of patients with refractory relapsed multiple myeloma were effective killers of OPM2 myeloma cells when treated with elotuzumab and lenalidomide, and this was associated with significantly increased expression of CD54 on OPM2 cells. Furthermore, elotuzumab- and lenalidomide-induced OPM2 cell killing and increased OPM2 CD54 expression were dependent on both monocytes and NK cells, and these effects were not mediated by soluble factors alone. At the transcript level, elotuzumab and lenalidomide treatment significantly increased OPM2 myeloma cell expression of genes for trafficking and adhesion molecules, NK cell activation ligands and antigen presentation molecules. In conclusion, our findings suggest that multiple myeloma patients require elotuzumab- and lenalidomide-mediated upregulation of CD54 on autologous myeloma cells, in combination with NK cells and monocytes to mediate an effective anti-tumor response. Furthermore, our data suggest that increased myeloma cell CD54 expression levels could be a powerful predictive biomarker for response to elotuzumab and lenalidomide treatment.


Assuntos
Mieloma Múltiplo , Animais , Camundongos , Humanos , Lenalidomida/farmacologia , Lenalidomida/uso terapêutico , Lenalidomida/metabolismo , Mieloma Múltiplo/metabolismo , Monócitos/metabolismo , Leucócitos Mononucleares/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Células Matadoras Naturais , Dexametasona/uso terapêutico
17.
Eur J Haematol ; 110(2): 168-176, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36321745

RESUMO

Multi-parametric flow cytometry (MFC) has a well-established role in measurable residual disease (MRD) monitoring in patients with B-lymphoblastic leukemia (B-ALL). However, the optimal time-point (TP) for early MRD testing and associated prognostic impact remain undefined in adult B-ALL patients receiving Hyper-CVAD induction chemotherapy. To evaluate the utility of MRD analysis after one cycle (TP1) in comparison to MRD analysis after two cycles (TP2) of induction treatment with Hyper-CVAD chemotherapy, we studied 49 adult B-ALL patients over a 10-year period (2010-2020) who had available bone marrow samples for morphological and MFC MRD assessments at the two separate TPs. Median times to TP1 and TP2 relative to start of treatment were 21 and 45 days, respectively. When censored at transplant, achievement of MRD negativity at TP1 was not associated with a statistically significant improvement in either event-free survival (EFS) (p = .426) or overall survival (OS) (p = .335) when compared to patients with MRD positivity. In contrast, achieving MRD negativity at TP2 was associated with a statistically significant improvement in both EFS (p = ·005) and OS (p = .047) over patients who remained MRD positive. Multivariate analysis demonstrated that KMT2A-rearrangement and MRD positivity at TP2 were the only significant predictors of outcome, correlating with worse EFS and OS. Therefore, in the absence of residual morphologic disease, MRD analysis after one cycle of Hyper-CVAD induction chemotherapy did not provide additional benefit with regard to risk stratification or correlation with survival outcomes when compared to MRD testing after two cycles of Hyper-CVAD in adult B-ALL patients.


Assuntos
Quimioterapia de Indução , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Humanos , Adulto , Citometria de Fluxo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamento farmacológico , Prognóstico , Neoplasia Residual/diagnóstico
18.
Transpl Infect Dis ; 25(1): e13994, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36413495

RESUMO

BACKGROUND: Cytomegalovirus (CMV) infection increases mortality and morbidity following allogeneic hematopoietic stem-cell transplantation (alloHSCT). Universal antiviral prophylaxis with letermovir is effective but unsubsidized in Australia. Valaciclovir demonstrates anti-CMV activity in high doses, but few current real-world studies explore its use as primary prophylaxis in high-risk patients post-alloHSCT. METHODS: We performed a retrospective analysis of alloHSCT recipients at high risk of clinically significant CMV infection (cs-CMVi), defined as a plasma CMV DNA viral load of >400 IU/ml requiring preemptive therapy, or CMV disease. High-risk recipients were CMV seropositive and underwent T-cell depleted, haploidentical or umbilical cord stem-cell transplants. Consecutive patients transplanted from July 2018 to January 2020, treated with valaciclovir 2 g TDS from day +7 to +100 (HD-VALA), were compared to a historical cohort (July 2017-June 2018) who only received preemptive CMV therapy, and standard valaciclovir (SD-VALA) for varicella/herpes prophylaxis. We compared incidence of and time to cs-CMVi. RESULTS: In the SD-VALA cohort (n = 27, median CMV follow-up duration 259 days), 23/27 (85%) developed cs-CMVi at a median of 39 days. For the HD-VALA cohort (n = 35, median CMV follow-up duration 216 days), 19/35 (54%) developed cs-CMVi, at a median of 68 days. Time to cs-CMVi was significantly longer in HD-VALA cohort (p < .0001). On multivariate analysis, HD VALA reduced the risk of cs-CMVi (HR 0.32, p = .0005). CONCLUSIONS: In alloHSCT recipients at high risk for cs-CMVi, HD-VALA resulted in lower cumulative reactivation, and delayed reactivation, reducing requirement for preemptive CMV therapy in the early post-engraftment period.


Assuntos
Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Humanos , Valaciclovir , Citomegalovirus , Estudos Retrospectivos , Infecções por Citomegalovirus/prevenção & controle , Antivirais/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos
19.
BMC Psychiatry ; 23(1): 22, 2023 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-36627578

RESUMO

BACKGROUND: One in eight children in the United Kingdom are estimated to have a mental health condition, and many do not receive support or treatment. The COVID-19 pandemic has negatively impacted mental health and disrupted the delivery of care. Prevalence of poor mental health is not evenly distributed across age groups, by sex or socioeconomic groups. Equity in access to mental health care is a policy priority but detailed socio-demographic trends are relatively under-researched. METHODS: We analysed records for all mental health prescriptions and referrals to specialist mental health outpatient care between the years of 2015 and 2021 for children aged 2 to 17 years in a single NHS Scotland health board region. We analysed trends in prescribing, referrals, and acceptance to out-patient treatment over time, and measured differences in treatment and service use rates by age, sex, and area deprivation. RESULTS: We identified 18,732 children with 178,657 mental health prescriptions and 21,874 referrals to specialist outpatient care. Prescriptions increased by 59% over the study period. Boys received double the prescriptions of girls and the rate of prescribing in the most deprived areas was double that in the least deprived. Mean age at first mental health prescription was almost 1 year younger in the most deprived areas than in the least. Referrals increased 9% overall. Initially, boys and girls both had an annual referral rate of 2.7 per 1000, but this fell 6% for boys and rose 25% for girls. Referral rate for the youngest decreased 67% but increased 21% for the oldest. The proportion of rejected referrals increased steeply since 2020 from 17 to 30%. The proportion of accepted referrals that were for girls rose to 62% and the mean age increased 1.5 years. CONCLUSIONS: The large increase in mental health prescribing and changes in referrals to specialist outpatient care aligns with emerging evidence of increasing poor mental health, particularly since the start of the COVID-19 pandemic. The static size of the population accepted for specialist treatment amid greater demand, and the changing demographics of those accepted, indicate clinical prioritisation and unmet need. Persistent inequities in mental health prescribing and referrals require urgent action.


Assuntos
COVID-19 , Atenção Secundária à Saúde , Masculino , Feminino , Criança , Humanos , Lactente , Dados de Saúde Coletados Rotineiramente , Saúde Mental , Pandemias , COVID-19/epidemiologia , Encaminhamento e Consulta
20.
Intern Med J ; 53(5): 717-722, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-35319139

RESUMO

BACKGROUND: Universal leucocyte depletion reduces the risk of transfusion-transmitted cytomegalovirus; however, many clinicians still prescribe cytomegalovirus seronegative units. AIM: Our retrospective study aims to confirm the low risk of transfusion-transmitted cytomegalovirus with leucocyte depletion alone and demonstrate the ongoing variability in cytomegalovirus seronegative transfusion prescribing. METHODS: Over a 9-year period (July 2009-July 2018), occurrences of transfusion transmitted cytomegalovirus in cytomegalovirus seronegative donor/recipient haemopoietic stem cell transplant pairs were compared at one allogeneic haemopoietic stem cell transplant centre providing cytomegalovirus seronegative blood products and leucocyte depletion (double prevention) versus another providing leucocyte depletion only (single prevention). Retrospective chart audit identified patient demographics, blood product exposure and cytomegalovirus infection by polymerase chain reaction. A separate audit examined cytomegalovirus seronegative blood product ordering in a broader range of hospital types. RESULTS: We identified 122 and 66 cytomegalovirus-negative donor/recipient haemopoietic stem cell transplant pairs using double and single transfusion prevention strategy respectively. Transfusion exposure to red cells and pooled platelets was similar, although more apheresis platelets were used in the double prevention group. The cytomegalovirus infection rate was 3 (2.4%) and zero in the double and single prevention groups respectively. Cytomegalovirus seronegative unit ordering was not limited to hospitals with obstetric or neonatal populations, suggesting ongoing reliance of cytomegalovirus seronegative units outside this population. CONCLUSIONS: The analysis suggests a double prevention strategy does not provide additional protection against transfusion-transmitted cytomegalovirus. There is ongoing variability in the acceptance of leucocyte depletion alone despite the low risk of cytomegalovirus infection.


Assuntos
Infecções por Citomegalovirus , Transplante de Células-Tronco Hematopoéticas , Recém-Nascido , Humanos , Citomegalovirus , Estudos Retrospectivos , Transfusão de Sangue , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/prevenção & controle
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