Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 92
Filtrar
1.
Small ; 19(21): e2207326, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36828794

RESUMO

Physiologically-based kinetic (PBK) modeling is a valuable tool to understand the kinetics of nanoparticles (NPs) in vivo. However, estimating PBK parameters remains challenging and commonly requires animal studies. To develop predictive models to estimate PBK parameter values based on NP characteristics, a database containing PBK parameter values and corresponding NP characteristics is needed. As a first step toward this objective, this study estimates PBK parameters for gold NPs (AuNPs) and provides a comparison of two different NPs. Two animal experiments are conducted in which varying doses of AuNPs attached with polyethylene glycol (PEG) are administered intravenously to rats. The resulting Au concentrations are used to estimate PBK model parameters. The parameters are compared with PBK parameters previously estimated for poly(alkyl cyanoacrylate) NPs loaded with cabazitaxel and for LipImage 815. This study shows that a small initial database of PBK parameters collected for three NPs is already sufficient to formulate new hypotheses on NP characteristics that may be predictive of PBK parameter values. Further research should focus on developing a larger database and on developing quantitative models to predict PBK parameter values.


Assuntos
Ouro , Nanopartículas Metálicas , Ratos , Animais , Cinética , Polietilenoglicóis , Cianoacrilatos
2.
Clin Exp Immunol ; 213(3): 371-383, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37070703

RESUMO

Acute T-cell-mediated rejection (aTCMR) still remains a clinical problem after kidney transplantation despite significant improvements in immunosuppressive regimens. Polyfunctional T cells, i.e. T cells producing multiple pro-inflammatory cytokines, are believed to be the most relevant T cells in an immune response. The aim of this study was to determine whether polyfunctional donor-reactive T cells are associated with aTCMR. In a case-control study, 49 kidney transplant recipients with a biopsy-proven aTCMR in the first year after transplantation were included, as well as 51 controls without aTCMR. Circulating donor-reactive T cells were identified by the expression of CD137 after short-term co-culture with donor antigen-presenting cells. Polyfunctional donor-reactive T cells were further characterized by dissection into different T-cell subsets encompassing the spectrum of naïve to terminally differentiated effector T cells. Prior to kidney transplantation, proportions of donor-reactive CD4+ (0.03% versus 0.02%; P < 0.01) and CD8+ (0.18% versus 0.10%; P < 0.01) CD137++ T cells were significantly higher in recipients with a biopsy-proven aTCMR versus non-rejectors. Polyfunctionality was higher (P = 0.03) in this subset of CD137-expressing T cells. These cells were predominantly of the EM/EMRA-phenotype, with polyfunctional donor-reactive CD137++CD4+ T cells predominantly co-expressing CD28 whereas approximately half of the polyfunctional CD137++CD8+ T cells co-expressed CD28. In addition, at the time of aTCMR, polyfunctional donor-reactive CD137++ CD4+, but not CD8+, T cells, were specifically decreased by 75% compared to before transplantation in recipients with as well as those without an aTCMR. Prior to transplantation, the proportion of polyfunctional donor-reactive CD137++ T cells is associated with the occurrence of a biopsy-proven aTCMR within the first year after transplantation.

3.
Nanomedicine ; 48: 102638, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36549551

RESUMO

Urinary extracellular vesicles (uEVs) are promising biomarkers for various diseases. However, many tools measuring uEVs rely on time-consuming uEV isolation methods, which could induce sample bias. This study demonstrates the detection of single uEVs without isolation using imaging flow cytometry (IFCM). Unstained urine samples contained auto-fluorescent (A-F) particles when characterized with IFCM. Centrifugation successfully removed A-F particles from the unprocessed urine. Based on the disappearance of A-F particles, a gate was defined to distinguish uEVs from A-F particles. The final readouts of IFCM were verified as single EVs based on detergent treatment and serial dilutions. When developing this protocol to measure urine samples with abnormally high protein levels, 25 mg/mL dithiothreitol (DTT) showed improved uEV recovery over 200 mg/mL DTT. This study provides an isolation-free protocol using IFCM to quantify and phenotype single uEVs, eliminating the hindrance and influence of A-F particles, protein aggregates, and coincidence events.


Assuntos
Vesículas Extracelulares , Citometria de Fluxo , Vesículas Extracelulares/metabolismo , Biomarcadores/metabolismo
4.
Ther Drug Monit ; 44(5): 625-632, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35358111

RESUMO

BACKGROUND: Intracellular tacrolimus concentration in peripheral blood mononuclear cells (PBMCs) (TAC [PBMC] ) has been proposed to better represent its active concentration than its whole blood concentration. As tacrolimus acts on T lymphocytes and other white blood cells, including monocytes, we investigated the association of tacrolimus concentration in CD3 + T lymphocytes (TAC [CD3] ) and CD14 + monocytes (TAC [CD14] ) with acute rejection after kidney transplantation. METHODS: From a total of 61 samples in this case-control study, 28 samples were obtained during biopsy-proven acute rejection (rejection group), and 33 samples were obtained in the absence of rejection (control group). PBMCs were collected from both cryopreserved (retrospectively) and freshly obtained (prospectively) samples. CD3 + T lymphocytes and CD14 + monocytes were isolated from PBMCs, and their intracellular tacrolimus concentrations were measured. RESULTS: The correlation between tacrolimus whole-blood and intracellular concentrations was poor. TAC [CD3] was significantly lower than TAC [CD14] (median 12.8 versus 81.6 pg/million cells; P < 0.001). No difference in TAC [PBMC] (48.5 versus 44.4 pg/million cells; P = 0.82), TAC [CD3] (13.4 versus 12.5 pg/million cells; P = 0.28), and TAC [CD14] (90.0 versus 72.8 pg/million cells; P = 0.27) was found between the rejection and control groups. However, freshly isolated PBMCs showed significantly higher TAC [PBMC] than PBMCs from cryopreserved samples. Subgroup analysis of intracellular tacrolimus concentrations from freshly isolated cells did not show a difference between rejectors and nonrejectors. CONCLUSIONS: Differences in TAC [CD3] and TAC [CD14] between patients with and without rejection could not be demonstrated. However, further optimization of the cell isolation process is required because a difference in TAC [PBMC] between fresh and cryopreserved cells was observed. These results need to be confirmed in a study with a larger number of patients.


Assuntos
Nefropatias , Transplante de Rim , Estudos de Casos e Controles , Rejeição de Enxerto , Humanos , Imunossupressores , Leucócitos Mononucleares , Monócitos , Complicações Pós-Operatórias , Estudos Retrospectivos , Linfócitos T , Tacrolimo
5.
Transpl Int ; 35: 10122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35387397

RESUMO

Background: In heart transplant recipients, donor-derived cell-free DNA (ddcfDNA) is a potential biomarker for acute rejection (AR), in that increased values may indicate rejection. For the assessment of ddcfDNA as new biomarker for rejection, blood plasma sampling around the endomyocardial biopsy (EMB) seems a practical approach. To evaluate the effect of the EMB procedure on ddcfDNA values, ddcfDNA values before the EMB were pairwise compared to ddcfDNA values after the EMB. We aimed at evaluating whether it matters whether the ddcfDNA sampling is done before or after the EMB-procedure. Methods: Plasma samples from heart transplant recipients were obtained pre-EMB and post-EMB. A droplet digital PCR method was used for measuring ddcfDNA, making use of single-nucleotide polymorphisms that allowed both relative quantification, as well as absolute quantification of ddcfDNA. Results: Pairwise comparison of ddcfDNA values pre-EMB with post-EMB samples (n = 113) showed significantly increased ddcfDNA concentrations and ddcfDNA% in post-EMB samples: an average 1.28-fold increase in ddcfDNA concentrations and a 1.31-fold increase in ddcfDNA% was observed (p = 0.007 and p = 0.03, respectively). Conclusion: The EMB procedure causes iatrogenic injury to the allograft that results in an increase in ddcfDNA% and ddcfDNA concentrations. For the assessment of ddcfDNA as marker for AR, collection of plasma samples before the EMB procedure is therefore essential.


Assuntos
Ácidos Nucleicos Livres , Transplante de Coração , Aloenxertos , Biomarcadores , Biópsia , Rejeição de Enxerto/diagnóstico , Humanos , Biópsia Líquida
6.
Int J Mol Sci ; 22(19)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34638835

RESUMO

Extracellular vesicles (EVs) are nanoparticles that transmit molecules from releasing cells to target cells. Recent studies link urinary EVs (uEV) to diverse processes such as infection and rejection after kidney transplantation. This, and the unmet need for biomarkers diagnosing kidney transplant dysfunction, has led to the current high level of interest in uEV. uEV provide non-intrusive access to local protein, DNA, and RNA analytics without invasive biopsy. To determine the added value of uEV measurements for detecting allograft dysfunction after kidney transplantation, we systematically included all related literature containing directly relevant information, with the addition of indirect evidence regarding urine or kidney injury without transplantation. According to their varying characteristics, uEV markers after transplantation could be categorized into kidney-specific, donor-specific, and immune response-related (IR-) markers. A few convincing studies have shown that kidney-specific markers (PODXL, ion cotransporters, SYT17, NGAL, and CD133) and IR-markers (CD3, multi-mRNA signatures, and viral miRNA) could diagnose rejection, BK virus-associated nephropathy, and calcineurin inhibitor nephrotoxicity after kidney transplantation. In addition, some indirect proof regarding donor-specific markers (donor-derived cell-free DNA) in urine has been demonstrated. Together, this literature review provides directions for exploring novel uEV markers' profiling complications after kidney transplantation.


Assuntos
Vesículas Extracelulares/metabolismo , Rejeição de Enxerto/urina , Transplante de Rim , Rim/metabolismo , Aloenxertos , Biomarcadores/urina , Vesículas Extracelulares/imunologia , Rejeição de Enxerto/imunologia , Humanos , Rim/imunologia , Rim/cirurgia
7.
J Foot Ankle Surg ; 60(2): 386-390, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33223437

RESUMO

Processed nerve allografts are used increasingly in the treatment of traumatic neuroma in small sensory nerves. The goal of the present study was to investigate the use of an allograft after different intervals between injury and repair and to analyze results, not only for the success of pain relief, but also for potential recovery of sensation in time. Four patients with painful neuroma in small sensory nerves in the lower extremity were surgically treated with a decellularized allograft. Patients were followed prospectively for at least 1 y. Clinical outcome was assessed using the Likert scale. Recovery of sensation was tested using Semmes-Weinstein monofilaments. In all 4 cases an allograft of 3-cm was used to reconstruct a defect in the superficial peroneal (3) or sural nerve (1) after excision of the neuroma. Complete relief of pain symptoms was achieved in 2 patients: 1 case concerned the reconstruction of a neuroma with an interval of less than 1 y between injury and repair and 1 case a neuroma-in-continuity. Sensation recovered completely in these 2 cases. In the other 2 cases, that had an interval between injury and reconstruction of more than 1 y, there was neither successful pain relief nor recovery of sensation. This prospective study shows that processed nerve allografts can be successful for the reconstruction of small sensory nerves after excision of the traumatic neuroma both for recovery of pain and sensation, but in this small case series only if the interval between injury and reconstruction was <1 y.


Assuntos
Neuroma , Aloenxertos , Humanos , Neuroma/etiologia , Neuroma/cirurgia , Estudos Prospectivos , Nervo Sural , Resultado do Tratamento
8.
Curr Opin Organ Transplant ; 26(1): 30-36, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33315764

RESUMO

PURPOSE OF REVIEW: DNA methylation is involved in gene transcription and as such important for cellular function. Here, the literature on DNA methylation in relation to acute rejection is summarized with a focus on the potential clinical utility of DNA methylation for monitoring transplant rejection. RECENT FINDINGS: The tight transcriptional control of DNA methylation in immune cell function, e.g. demethylation in regulatory T-cell-specific genes for stable immunosuppressive capacities, suggests an important role for DNA methylation variations in the antidonor-directed immune response. Until today, differentially methylated DNA in immune cells, however, has not been described at the moment of allograft rejection. The ability to locus-specific modify DNA methylation could facilitate the generation of stable cells for cellular therapy purposes. The unique cell-specific characteristics of DNA methylation provide the opportunity to identify its cellular origin. Examining methylation of cell-free DNA in blood or urine may serve as a 'liquid biopsy' enabling minimally invasive detection of allograft rejection. SUMMARY: Actual research publications on DNA methylation in relation to allograft rejection are scarce, which makes it challenging to determine its potential clinical value. Extensive research is needed to investigate the value of DNA methylation in early recognition, diagnosis, and/or successful treatment of allograft rejection.


Assuntos
Metilação de DNA/imunologia , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Terapia de Imunossupressão/métodos , Transplante de Rim/efeitos adversos , Aloenxertos , Humanos , Imunossupressores/uso terapêutico , Complicações Pós-Operatórias/patologia
9.
BMC Womens Health ; 20(1): 41, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32131802

RESUMO

BACKGROUND: Hypertensive disorders of pregnancy (HDP), such as preeclampsia (PE) or the Hemolysis Elevated Liver enzymes and Low Platelets (HELLP) syndrome are associated with elevated cardiovascular disease (CVD) risks, but standardized prevention guidelines after such pregnancies are lacking. Hypertension is the first emerging risk factor after PE/HELLP pregnancies and is a major risk factor for CVD. Hypertension before the age of 55 years may lead to various manifestations of end-organ damage at relatively young age. Therefore, timely treatment of elevated blood pressure is mandatory, but many of these high-risk women have long-term undetected and untreated hypertension before adequate treatment is initiated. AIM: The aim of our study is to assess whether home blood pressure monitoring (HBPM) in women with a previous PE/HELLP pregnancy is a valuable tool for the early detection of hypertension. METHODS: Women with a history of both early and late PE/HELLP syndrome aged 40-60 years are invited to participate. Patients with a history of CVD, known hypertension and/or use of antihypertensive medication are excluded. Women are randomized between HPBM or 'usual care'. The primary outcome is feasibility and usability of HBPM after 1 year of follow-up. Secondary outcomes will be the effectiveness of HPBM to detect hypertension, the efficacy of BP treatment, quality of life, health-related symptoms, work ability, and life-style behaviour. The results of this study will provide better strategies for timely detection and prevention of hypertension in women after PE/HELLP. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03228082. Registered June 15, 2017.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea/fisiologia , Síndrome HELLP/fisiopatologia , Hipertensão/prevenção & controle , Pré-Eclâmpsia/diagnóstico , Qualidade de Vida/psicologia , Adulto , Fatores Etários , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Hipertensão/complicações , Pessoa de Meia-Idade , Gravidez , Complicações na Gravidez , Resultado da Gravidez
10.
Lancet ; 392(10143): 232-243, 2018 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-30047376

RESUMO

BACKGROUND: More than 1·8 million new cases of HIV-1 infection were diagnosed worldwide in 2016. No licensed prophylactic HIV-1 vaccine exists. A major limitation to date has been the lack of direct comparability between clinical trials and preclinical studies. We aimed to evaluate mosaic adenovirus serotype 26 (Ad26)-based HIV-1 vaccine candidates in parallel studies in humans and rhesus monkeys to define the optimal vaccine regimen to advance into clinical efficacy trials. METHODS: We conducted a multicentre, randomised, double-blind, placebo-controlled phase 1/2a trial (APPROACH). Participants were recruited from 12 clinics in east Africa, South Africa, Thailand, and the USA. We included healthy, HIV-1-uninfected participants (aged 18-50 years) who were considered at low risk for HIV-1 infection. We randomly assigned participants to one of eight study groups, stratified by region. Participants and investigators were blinded to the treatment allocation throughout the study. We primed participants at weeks 0 and 12 with Ad26.Mos.HIV (5 × 1010 viral particles per 0·5 mL) expressing mosaic HIV-1 envelope (Env)/Gag/Pol antigens and gave boosters at weeks 24 and 48 with Ad26.Mos.HIV or modified vaccinia Ankara (MVA; 108 plaque-forming units per 0·5 mL) vectors with or without high-dose (250 µg) or low-dose (50 µg) aluminium adjuvanted clade C Env gp140 protein. Those in the control group received 0·9% saline. All study interventions were administered intramuscularly. Primary endpoints were safety and tolerability of the vaccine regimens and Env-specific binding antibody responses at week 28. Safety and immunogenicity were also assessed at week 52. All participants who received at least one vaccine dose or placebo were included in the safety analysis; immunogenicity was analysed using the per-protocol population. We also did a parallel study in rhesus monkeys (NHP 13-19) to assess the immunogenicity and protective efficacy of these vaccine regimens against a series of six repetitive, heterologous, intrarectal challenges with a rhesus peripheral blood mononuclear cell-derived challenge stock of simian-human immunodeficiency virus (SHIV-SF162P3). The APPROACH trial is registered with ClinicalTrials.gov, number NCT02315703. FINDINGS: Between Feb 24, 2015, and Oct 16, 2015, we randomly assigned 393 participants to receive at least one dose of study vaccine or placebo in the APPROACH trial. All vaccine regimens demonstrated favourable safety and tolerability. The most commonly reported solicited local adverse event was mild-to-moderate pain at the injection site (varying from 69% to 88% between the different active groups vs 49% in the placebo group). Five (1%) of 393 participants reported at least one grade 3 adverse event considered related to the vaccines: abdominal pain and diarrhoea (in the same participant), increased aspartate aminotransferase, postural dizziness, back pain, and malaise. The mosaic Ad26/Ad26 plus high-dose gp140 boost vaccine was the most immunogenic in humans; it elicited Env-specific binding antibody responses (100%) and antibody-dependent cellular phagocytosis responses (80%) at week 52, and T-cell responses at week 50 (83%). We also randomly assigned 72 rhesus monkeys to receive one of five different vaccine regimens or placebo in the NHP 13-19 study. Ad26/Ad26 plus gp140 boost induced similar magnitude, durability, and phenotype of immune responses in rhesus monkeys as compared with humans and afforded 67% protection against acquisition of SHIV-SF162P3 infection (two-sided Fisher's exact test p=0·007). Env-specific ELISA and enzyme-linked immunospot assay responses were the principal immune correlates of protection against SHIV challenge in monkeys. INTERPRETATION: The mosaic Ad26/Ad26 plus gp140 HIV-1 vaccine induced comparable and robust immune responses in humans and rhesus monkeys, and it provided significant protection against repetitive heterologous SHIV challenges in rhesus monkeys. This vaccine concept is currently being evaluated in a phase 2b clinical efficacy study in sub-Saharan Africa (NCT03060629). FUNDING: Janssen Vaccines & Prevention BV, National Institutes of Health, Ragon Institute of MGH, MIT and Harvard, Henry M Jackson Foundation for the Advancement of Military Medicine, US Department of Defense, and International AIDS Vaccine Initiative.


Assuntos
Vacinas contra a AIDS/administração & dosagem , HIV-1/imunologia , Vacinas contra a AIDS/efeitos adversos , Dor Abdominal/etiologia , Adenoviridae , Adolescente , Adulto , Animais , Aspartato Aminotransferases/análise , Dor nas Costas/etiologia , Diarreia/etiologia , Tontura/etiologia , Relação Dose-Resposta a Droga , Método Duplo-Cego , Fadiga/etiologia , Vetores Genéticos , Voluntários Saudáveis , Humanos , Imunidade Celular , Imunidade Humoral , Macaca mulatta , Pessoa de Meia-Idade , Adulto Jovem
11.
J Vasc Interv Radiol ; 30(11): 1832-1839, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31235411

RESUMO

PURPOSE: To evaluate hand sensibility after transradial access (TRA) in patients with and without radial artery occlusion (RAO). MATERIALS AND METHODS: In this study, 71 patients with and without RAO after TRA for a coronary intervention were studied (79% male, mean age 65 y ± 9). Sensibility testing of both hands was performed with the Semmes-Weinstein monofilaments test. The primary endpoint was abnormal sensibility, defined as diminished sensibility in at least 1 radial nerve-supplied dermatome. The contralateral hand served as control. The influence of TRA, RAO, and clinical characteristics on hand sensibility was evaluated. RESULTS: In patients with RAO, more abnormal sensibility was observed on the RAO side compared with the control hand (72% vs 17%, P < .01). In patients without RAO, more abnormal sensibility was observed in the TRA hand compared with the control hand (43% vs 10%, P < .01). When analyzing all hands separately, TRA, RAO, and diabetes were independent predictors for abnormal hand sensibility in a multivariate model (odds ratio 3.8, 95% confidence interval 1.4-9.8, P < .01; odds ratio 3.0, 95% confidence interval 1.1-8.5, P = .03; odds ratio 3.5, 95% confidence interval 1.4-8.6, P < .01). CONCLUSIONS: TRA and RAO are associated with diminished hand sensibility.


Assuntos
Arteriopatias Oclusivas/complicações , Cateterismo Periférico/efeitos adversos , Mãos/irrigação sanguínea , Mãos/inervação , Artéria Radial/fisiopatologia , Transtornos de Sensação/etiologia , Limiar Sensorial , Grau de Desobstrução Vascular , Idoso , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Punções , Artéria Radial/diagnóstico por imagem , Fatores de Risco , Transtornos de Sensação/diagnóstico , Transtornos de Sensação/fisiopatologia , Resultado do Tratamento
12.
BMC Psychiatry ; 19(1): 106, 2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30943927

RESUMO

BACKGROUND: Increasing attention to palliative care for the general population has led to the development of various evidence-based or consensus-based tools and interventions. However, specific tools and interventions are needed for people with severe mental illness (SMI) who have a life-threatening illness. The aim of this systematic review is to summarize the scientific evidence on tools and interventions in palliative care for this group. METHODS: Systematic searches were done in the PubMed, Cochrane Library, CINAHL, PsycINFO and Embase databases, supplemented by reference tracking, searches on the internet with free text terms, and consultations with experts to identify relevant literature. Empirical studies with qualitative, quantitative or mixed-methods designs concerning tools and interventions for use in palliative care for people with SMI were included. Methodological quality was assessed using a critical appraisal instrument for heterogeneous study designs. Stepwise study selection and the assessment of methodological quality were done independently by two review authors. RESULTS: Four studies were included, reporting on a total of two tools and one multi-component intervention. One study concerned a tool to identify the palliative phase in patients with SMI. This tool appeared to be usable only in people with SMI with a cancer diagnosis. Furthermore, two related studies focused on a tool to involve people with SMI in discussions about medical decisions at the end of life. This tool was assessed as feasible and usable in the target group. One other study concerned the Dutch national Care Standard for palliative care, including a multi-component intervention. The Palliative Care Standard also appeared to be feasible and usable in a mental healthcare setting, but required further tailoring to suit this specific setting. None of the included studies investigated the effects of the tools and interventions on quality of life or quality of care. CONCLUSIONS: Studies of palliative care tools and interventions for people with SMI are scarce. The existent tools and intervention need further development and should be tailored to the care needs and settings of these people. Further research is needed on the feasibility, usability and effects of tools and interventions for palliative care for people with SMI.


Assuntos
Transtornos Mentais/terapia , Saúde Mental/estatística & dados numéricos , Cuidados Paliativos/métodos , Qualidade de Vida , Tomada de Decisões , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Apoio Social
13.
Cytotherapy ; 20(7): 919-929, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29934259

RESUMO

BACKGROUND: Mesenchymal stromal cells (MSCs) are studied for their immunotherapeutic potential. Prior to therapeutic use, MSCs are culture expanded to obtain the required cell numbers and, to improve their efficacy, MSCs may be primed in vitro. Culture expansion and priming induce phenotypical and functional changes in MSCs and thus standardisation and quality control measurements come in need. We investigated the impact of priming and culturing on MSC DNA methylation and examined the use of epigenetic profiling as a quality control tool. METHODS: Human umbilical cord-derived MSCs (ucMSCs) were cultured for 3 days with interferon (IFN)γ, transforming growth factor (TGF)ß or a multi-factor combination (MC; IFNγ, TGFß and retinoic acid). In addition, ucMSCs were culture expanded for 14 days. Phenotypical changes and T-cell proliferation inhibition capacity were examined. Genome-wide DNA methylation was measured with Infinium MethylationEPIC Beadchip. RESULTS: Upon priming, ucMSCs exhibited a different immunophenotype and ucMSC(IFNγ) and ucMSC(MC) had an increased capacity to inhibit T-cell proliferation. DNA methylation patterns were minimally affected by priming, with only one significantly differentially methylated site (DMS) in IFNγ- and MC-primed ucMSCs associated with autophagy activity. In contrast, 14 days after culture expansion, ucMSCs displayed minor phenotypical and functional changes but showed >4000 significantly DMSs, mostly concerning genes involved in membrane composition, cell adhesion and transmembrane signalling. DISCUSSION: These data show that DNA methylation of MSCs is only marginally affected by priming, whereas culture expansion and subsequent increased cellular interactions have a large impact on methylation. On account of this study, we suggest that DNA methylation analysis is a useful quality control tool for culture expanded therapeutic MSCs.


Assuntos
Técnicas de Cultura de Células/métodos , Epigênese Genética , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical/citologia , Biomarcadores/metabolismo , Forma Celular , Células Cultivadas , Metilação de DNA/genética , Humanos , Imunofenotipagem , Interferon gama/metabolismo , Células-Tronco Mesenquimais/citologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
Ther Drug Monit ; 40(5): 515-525, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29957668

RESUMO

Despite modern immunosuppressive therapy, allograft rejection remains a major cause of solid organ transplant dysfunction. For clinical care, organ transplant function is routinely monitored by measuring biomarkers that, depending on the organ transplanted, include serum creatinine, N-terminal pro-hormone of brain natriuretic peptide (NT-proBNP), and aspartate aminotransferase. All can be measured easily in clinical chemistry laboratories. The main problem with these biomarkers is that they have a low sensitivity for the detection of allograft damage and are nonspecific for the detection of allograft rejection. To diagnose rejection, histologic examination of grafted tissue is necessary, which requires an invasive biopsy procedure. There is thus an unmet need in transplantation medicine for biomarkers that are specific for rejection, identify graft injury at an early stage, and may eventually overcome the need for a transplant biopsy. Recently, tremendous progress in the field of biomarkers has been made. In this narrative review, the potential of donor-derived cell-free DNA (ddcfDNA), cell-free nucleosomes, and extracellular vesicles to act as next-generation biomarkers for solid organ transplant is discussed. Based on the fact that cell content is released during rejection, these markers could serve as very specific biomarkers for allograft injury and rejection. These markers have the potential to improve rejection monitoring, evaluate the response to antirejection therapy, and may decrease the need for invasive procedures.


Assuntos
Biomarcadores/sangue , Biomarcadores/urina , Rejeição de Enxerto/diagnóstico , Biópsia Líquida/métodos , Ácidos Nucleicos Livres/sangue , Ácidos Nucleicos Livres/urina , Vesículas Extracelulares/metabolismo , Rejeição de Enxerto/sangue , Rejeição de Enxerto/urina , Humanos , Nucleossomos/metabolismo
15.
Kidney Int ; 91(5): 1203-1213, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27988212

RESUMO

Natural occurring regulatory T cells (nTregs) have the potential to offer a targeted approach of immunosuppression and are the cell type of interest for inducing tolerance in kidney transplantation. End-stage renal disease (ESRD) profoundly affects the composition and function of circulating T cells but little is known with respect to how nTreg potential is affected. To address this, nTregs of patients with ESRD (on dialysis or not) and healthy individuals were isolated, expanded using allogeneic mature monocyte-derived dendritic cells followed by anti-CD3/anti-CD28-coated beads and the different nTregs were extensively characterized by the demethylation status of the Treg-specific demethylated region within FOXP3 and expression of typical nTreg markers. Additionally, the suppressive capacity as well as cytokine producing cells were analyzed for allogeneic mature monocyte-derived dendritic cell-expanded nTregs. Compared to age- and gender-matched healthy individuals, similar frequencies of nTregs were present within the circulation of patients with ESRD either on dialysis or not. The isolated nTregs could be equally well or even better expanded using allogeneic mature monocyte-derived dendritic cells and extensive characterization did not reveal significant differences. The demethylation status of the Treg-specific demethylated region was maintained or even further promoted as was the expression of markers characteristic for nTregs. Moreover, suppressive capacity and the cytokine profile of allogeneic mature monocyte-derived dendritic cell-expanded nTregs was similar to that of healthy individuals. Thus, circulating nTregs of patients with ESRD can effectively be expanded to stable allo antigen-specific nTregs with potential clinical applicability.


Assuntos
Células Dendríticas/imunologia , Fatores de Transcrição Forkhead/metabolismo , Terapia de Imunossupressão/métodos , Falência Renal Crônica/imunologia , Transplante de Rim , Linfócitos T Reguladores/transplante , Adulto , Idoso , Animais , Separação Celular/métodos , Citocinas/metabolismo , Células Dendríticas/metabolismo , Estudos de Viabilidade , Citometria de Fluxo/métodos , Humanos , Subunidade alfa de Receptor de Interleucina-2 , Isoantígenos , Falência Renal Crônica/sangue , Masculino , Metilação , Pessoa de Meia-Idade , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Adulto Jovem
16.
Cardiovasc Diabetol ; 16(1): 67, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28526033

RESUMO

BACKGROUND: Multiple bloodglucose-lowering agents have been linked to cardiovascular events. Preliminary studies showed improvement in left ventricular (LV) function during glucagon-like peptide-1 receptor agonist administration. Underlying mechanisms, however, are unclear. The purpose of this study was to investigate myocardial perfusion and oxidative metabolism in type 2 diabetic (T2DM) patients with LV systolic dysfunction as compared to healthy controls. Furthermore, effects of 26-weeks of exenatide versus insulin glargine administration on cardiac function, perfusion and oxidative metabolism in T2DM patients with LV dysfunction were explored. METHODS AND RESULTS: Twenty-six T2DM patients with LV systolic dysfunction (cardiac magnetic resonance (CMR) derived LV ejection fraction (LVEF) of 47 ± 13%) and 10 controls (LVEF of 59 ± 4%, P < 0.01 as compared to patients) were analyzed. Both myocardial perfusion during adenosine-induced hyperemia (P < 0.01), and coronary flow reserve (P < 0.01), measured by [15O]H2O positron emission tomography (PET), were impaired in T2DM patients as compared to healthy controls. Myocardial oxygen consumption and myocardial efficiency, measured using [11C]acetate PET and CMR derived stroke volume, were not different between the groups. Eleven patients in the exenatide group and 12 patients in the insulin glargine group completed the trial. Systemic metabolic control was improved after both treatments, although, no changes in cardiac function, perfusion and metabolism were seen after exenatide or insulin glargine. CONCLUSIONS: T2DM patients with LV systolic dysfunction did not have altered myocardial efficiency as compared to healthy controls. Exenatide or insulin glargine had no effects on cardiac function, perfusion or oxidative metabolism. Trial registration NCT00766857.


Assuntos
Circulação Coronária/efeitos dos fármacos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cardiomiopatias Diabéticas/tratamento farmacológico , Metabolismo Energético/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Incretinas/uso terapêutico , Insulina Glargina/uso terapêutico , Miocárdio/metabolismo , Peptídeos/uso terapêutico , Peçonhas/uso terapêutico , Disfunção Ventricular Esquerda/tratamento farmacológico , Função Ventricular Esquerda/efeitos dos fármacos , Idoso , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/diagnóstico , Cardiomiopatias Diabéticas/diagnóstico por imagem , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/fisiopatologia , Exenatida , Feminino , Humanos , Hipoglicemiantes/efeitos adversos , Incretinas/efeitos adversos , Insulina Glargina/efeitos adversos , Imagem Cinética por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão do Miocárdio/métodos , Miocárdio/patologia , Países Baixos , Oxirredução , Consumo de Oxigênio , Peptídeos/efeitos adversos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Recuperação de Função Fisiológica , Volume Sistólico , Sístole , Fatores de Tempo , Resultado do Tratamento , Peçonhas/efeitos adversos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/fisiopatologia
17.
J Immunol ; 194(11): 5282-93, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-25917092

RESUMO

Expansion of Ag-specific naturally occurring regulatory T cells (nTregs) is required to obtain sufficient numbers of cells for cellular immunotherapy. In this study, different allogeneic stimuli were studied for their capacity to generate functional alloantigen-specific nTregs. A highly enriched nTreg fraction (CD4(+)CD25(bright)CD127(-) T cells) was alloantigen-specific expanded using HLA-mismatched immature, mature monocyte-derived dendritic cells (moDCs), or PBMCs. The allogeneic mature moDC-expanded nTregs were fully characterized by analysis of the demethylation status within the Treg-specific demethylation region of the FOXP3 gene and the expression of both protein and mRNA of FOXP3, HELIOS, CTLA4, and cytokines. In addition, the Ag-specific suppressive capacity of these expanded nTregs was tested. Allogeneic mature moDCs and skin-derived DCs were superior in inducing nTreg expansion compared with immature moDCs or PBMCs in an HLA-DR- and CD80/CD86-dependent way. Remarkably, the presence of exogenous IL-15 without IL-2 could facilitate optimal mature moDC-induced nTreg expansion. Allogeneic mature moDC-expanded nTregs were at low ratios (<1:320), potent suppressors of alloantigen-induced proliferation without significant suppression of completely HLA-mismatched, Ag-induced proliferation. Mature moDC-expanded nTregs were highly demethylated at the Treg-specific demethylation region within the FOXP3 gene and highly expressed of FOXP3, HELIOS, and CTLA4. A minority of the expanded nTregs produced IL-10, IL-2, IFN-γ, and TNF-α, but few IL-17-producing nTregs were found. Next-generation sequencing of mRNA of moDC-expanded nTregs revealed a strong induction of Treg-associated mRNAs. Human allogeneic mature moDCs are highly efficient stimulator cells, in the presence of exogenous IL-15, for expansion of stable alloantigen-specific nTregs with superior suppressive function.


Assuntos
Células Dendríticas/efeitos dos fármacos , Interleucina-15/farmacologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Sequência de Bases , Antígenos CD4/metabolismo , Antígeno CTLA-4/biossíntese , Antígeno CTLA-4/genética , Diferenciação Celular/imunologia , Proliferação de Células , Células Cultivadas , Metilação de DNA , Células Dendríticas/imunologia , Fatores de Transcrição Forkhead/biossíntese , Fatores de Transcrição Forkhead/genética , Antígenos HLA-DR/imunologia , Humanos , Fator de Transcrição Ikaros/biossíntese , Fator de Transcrição Ikaros/genética , Interferon gama/biossíntese , Interleucina-10/biossíntese , Interleucina-15/imunologia , Interleucina-17/biossíntese , Interleucina-2/biossíntese , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-7/metabolismo , Análise de Sequência de RNA , Pele/citologia , Pele/imunologia , Fator de Necrose Tumoral alfa/biossíntese
18.
Acta Obstet Gynecol Scand ; 96(2): 158-165, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27861697

RESUMO

INTRODUCTION: Large practice variation exists in mode of delivery after cesarean section, suggesting variation in implementation of contemporary guidelines. We aim to evaluate this practice variation and to what extent this can be explained by risk factors at patient level. MATERIAL AND METHODS: This retrospective cohort study was performed among 17 Dutch hospitals in 2010. Women with one prior cesarean section without a contraindication for a trial of labor were included. We used multivariate logistic regression analysis to develop models for risk factor adjustments. One model was derived to adjust the elective repeat cesarean section rates; a second model to adjust vaginal birth after cesarean rates. Standardized rates of elective repeat cesarean section and vaginal birth after cesarean per hospital were compared. Pseudo-R2 measures were calculated to estimate the percentage of practice variation explained by the models. Secondary outcomes were differences in practice variation between hospital types and the correlation between standardized elective repeat cesarean section and vaginal birth after cesarean rates. RESULTS: In all, 1068 women had a history of cesarean section, of whom 71% were eligible for inclusion. A total of 515 women (67%) had a trial of labor, of whom 72% delivered vaginally. The elective repeat cesarean section rate at hospital level ranged from 6 to 54% (mean 29.8, standard deviation 11.8%). Vaginal birth after cesarean rates ranged from 50 to 90% (mean 71.8%, standard deviation 11.1%). More than 85% of this practice variation could not be explained by risk factors at patient level. CONCLUSION: A large practice variation exists in elective repeat cesarean section and vaginal birth after cesarean rates that can only partially be explained by risk factors at patient level.


Assuntos
Recesariana/estatística & dados numéricos , Nascimento Vaginal Após Cesárea/estatística & dados numéricos , Adulto , Estudos de Coortes , Feminino , Hospitais/estatística & dados numéricos , Humanos , Análise Multivariada , Países Baixos/epidemiologia , Padrões de Prática Médica/estatística & dados numéricos , Gravidez , Estudos Retrospectivos , Fatores de Risco , Prova de Trabalho de Parto
19.
BMC Pregnancy Childbirth ; 17(1): 284, 2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-28870155

RESUMO

BACKGROUND: Preterm birth is in quantity and in severity the most important topic in obstetric care in the developed world. Progestogens and cervical pessaries have been studied as potential preventive treatments with conflicting results. So far, no study has compared both treatments. METHODS/DESIGN: The Quadruple P study aims to compare the efficacy of vaginal progesterone and cervical pessary in the prevention of adverse perinatal outcome associated with preterm birth in asymptomatic women with a short cervix, in singleton and multiple pregnancies separately. It is a nationwide open-label multicentre randomized clinical trial (RCT) with a superiority design and will be accompanied by an economic analysis. Pregnant women undergoing the routine anomaly scan will be offered cervical length measurement between 18 and 22 weeks in a singleton and at 16-22 weeks in a multiple pregnancy. Women with a short cervix, defined as less than, or equal to 35 mm in a singleton and less than 38 mm in a multiple pregnancy, will be invited to participate in the study. Eligible women will be randomly allocated to receive either progesterone or a cervical pessary. Following randomization, the silicone cervical pessary will be placed during vaginal examination or 200 mg progesterone capsules will be daily self-administered vaginally. Both interventions will be continued until 36 weeks gestation or until delivery, whichever comes first. Primary outcome will be composite adverse perinatal outcome of perinatal mortality and perinatal morbidity including bronchopulmonary dysplasia, intraventricular haemorrhage grade III and IV, periventricular leukomalacia higher than grade I, necrotizing enterocolitis higher than stage I, Retinopathy of prematurity (ROP) or culture proven sepsis. These outcomes will be measured up until 10 weeks after the expected due date. Secondary outcomes will be, among others, time to delivery, preterm birth rate before 28, 32, 34 and 37 weeks, admission to neonatal intensive care unit, maternal morbidity, maternal admission days for threatened preterm labour and costs. DISCUSSION: This trial will provide evidence on whether vaginal progesterone or a cervical pessary is more effective in decreasing adverse perinatal outcome in both singletons and multiples. TRIAL REGISTRATION: Trial registration number: NTR 4414 . Date of registration January 29th 2014.


Assuntos
Colo do Útero/patologia , Pessários , Nascimento Prematuro/prevenção & controle , Progesterona/administração & dosagem , Progestinas/administração & dosagem , Doenças do Colo do Útero/complicações , Administração Intravaginal , Adolescente , Adulto , Medida do Comprimento Cervical , Protocolos Clínicos , Feminino , Humanos , Gravidez , Resultado da Gravidez , Nascimento Prematuro/etiologia , Resultado do Tratamento , Doenças do Colo do Útero/diagnóstico por imagem , Doenças do Colo do Útero/patologia , Adulto Jovem
20.
Psychogeriatrics ; 17(6): 356-363, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28417534

RESUMO

BACKGROUND: Cognitive deficits have been reported in older cardiac patients. An underlying mechanism for these findings may be reduced cardiac function. The relationship between cardiac function as represented by different echocardiographic measures and different cognitive function domains in older cardiac patients remains unknown. METHODS: An older (≥70 years) heterogeneous group of 117 community-dwelling cardiac patients under medical supervision by a cardiologist underwent thorough echocardiographic assessment including left ventricular ejection fraction, cardiac index, left atrial volume index, left ventricular mass index, left ventricular diastolic function, and valvular calcification. During a home visit, a neuropsychological assessment was performed within 7.1 ± 3.8 months after echocardiographic assessment; the neuropsychological assessment included three subtests of a word-learning test (encoding, recall, recognition) to examine one memory function domain and three executive function tests, including digit span backwards, Trail Making Test B minus A, and the Stroop colour-word test. RESULTS: Regression analyses showed no significant linear or quadratic associations between any of the echocardiographic functions and the cognitive function measures. CONCLUSIONS: None of the echocardiographic measures as representative of cardiac function was correlated with memory or executive function in this group of community-dwelling older cardiac patients. These findings contrast with those of previous studies.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Cognição/fisiologia , Ecocardiografia , Função Executiva/fisiologia , Memória/fisiologia , Testes Neuropsicológicos/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Vida Independente , Masculino , Países Baixos , Análise de Regressão
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA