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1.
Am J Transplant ; 21(3): 1012-1026, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33225626

RESUMEN

The complement system plays a pivotal role in the pathogenesis of ischemia-reperfusion injury in solid organ transplantation. Mirococept is a potent membrane-localizing complement inhibitor that can be administered ex vivo to the donor kidney prior to transplantation. To evaluate the efficacy of Mirococept in reducing delayed graft function (DGF) in deceased donor renal transplantation, we undertook the efficacy of mirococept (APT070) for preventing ischaemia-reperfusion injury in the kidney allograft (EMPIRIKAL) trial (ISRCTN49958194). A dose range of 5-25 mg would be tested, starting with 10 mg in cohort 1. No significant difference between Mirococept at 10 mg and control was detected; hence the study was stopped to enable a further dose saturation study in a porcine kidney model. The optimal dose of Mirococept in pig kidney was 80 mg. This dose did not induce any additional histological damage compared to controls or after a subsequent 3 hours of normothermic machine perfusion. The amount of unbound Mirococept postperfusion was found to be within the systemic dose range considered safe in the Phase I trial. The ex vivo administration of Mirococept is a safe and feasible approach to treat DGF in deceased donor kidney transplantation. The porcine kidney study identified an optimal dose of 80 mg (equivalent to 120 mg in human kidney) that provides a basis for further clinical development.


Asunto(s)
Trasplante de Riñón , Daño por Reperfusión , Animales , Inactivadores del Complemento , Funcionamiento Retardado del Injerto/tratamiento farmacológico , Funcionamiento Retardado del Injerto/prevención & control , Supervivencia de Injerto , Humanos , Riñón , Trasplante de Riñón/efectos adversos , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/prevención & control , Porcinos , Donantes de Tejidos
2.
Am J Transplant ; 20(4): 1125-1136, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31715056

RESUMEN

Regulatory T cells (Tregs) are a lymphocyte subset with intrinsic immunosuppressive properties that can be expanded in large numbers ex vivo and have been shown to prevent allograft rejection and promote tolerance in animal models. To investigate the safety, applicability, and biological activity of autologous Treg adoptive transfer in humans, we conducted an open-label, dose-escalation, Phase I clinical trial in liver transplantation. Patients were enrolled while awaiting liver transplantation or 6-12 months posttransplant. Circulating Tregs were isolated from blood or leukapheresis, expanded under good manufacturing practices (GMP) conditions, and administered intravenously at either 0.5-1 million Tregs/kg or 3-4.5 million Tregs/kg. The primary endpoint was the rate of dose- limiting toxicities occurring within 4 weeks of infusion. The applicability of the clinical protocol was poor unless patient recruitment was deferred until 6-12 months posttransplant. Thus, only 3 of the 17 patients who consented while awaiting liver transplantation were dosed. In contrast, all six patients who consented 6-12 months posttransplant received the cell infusion. Treg transfer was safe, transiently increased the pool of circulating Tregs and reduced anti-donor T cell responses. Our study opens the door to employing Treg immunotherapy to facilitate the reduction or complete discontinuation of immunosuppression following liver transplantation.


Asunto(s)
Trasplante de Hígado , Linfocitos T Reguladores , Traslado Adoptivo , Animales , Humanos , Terapia de Inmunosupresión , Donantes de Tejidos
3.
Am J Transplant ; 18(6): 1370-1379, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29392897

RESUMEN

Improvements in immunosuppression have modified short-term survival of deceased-donor allografts, but not their rate of long-term failure. Mismatches between donor and recipient HLA play an important role in the acute and chronic allogeneic immune response against the graft. Perfect matching at clinically relevant HLA loci does not obviate the need for immunosuppression, suggesting that additional genetic variation plays a critical role in both short- and long-term graft outcomes. By combining patient data and samples from supranational cohorts across the United Kingdom and European Union, we performed the first large-scale genome-wide association study analyzing both donor and recipient DNA in 2094 complete renal transplant-pairs with replication in 5866 complete pairs. We studied deceased-donor grafts allocated on the basis of preferential HLA matching, which provided some control for HLA genetic effects. No strong donor or recipient genetic effects contributing to long- or short-term allograft survival were found outside the HLA region. We discuss the implications for future research and clinical application.


Asunto(s)
Estudio de Asociación del Genoma Completo , Trasplante de Riñón , Donantes de Tejidos , Receptores de Trasplantes , Adulto , Replicación del ADN , Femenino , Genotipo , Supervivencia de Injerto/inmunología , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Trasplante Homólogo
4.
Kidney Int ; 91(2): 477-492, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27988211

RESUMEN

Chronic antibody-mediated rejection, a common cause of renal transplant failure, has a variable clinical phenotype. Understanding why some with chronic antibody-mediated rejection progress slowly may help develop more effective therapies. B lymphocytes act as antigen-presenting cells for in vitro indirect antidonor interferon-γ production in chronic antibody-mediated rejection, but many patients retain the ability to regulate these responses. Here we test whether particular patterns of T and B cell antidonor response associate with the variability of graft dysfunction in chronic antibody-mediated rejection. Our results confirm that dynamic changes in indirect antidonor CD4+ T-cell responses correlate with changes in estimated glomerular filtration rates, independent of other factors. Graft dysfunction progressed rapidly in patients who developed unregulated B-cell-driven interferon-γ production. However, conversion to a regulated or nonreactive pattern, which could be achieved by optimization of immunosuppression, associated with stabilization of graft function. Functional regulation by B cells appeared to activate an interleukin-10 autocrine pathway in CD4+ T cells that, in turn, impacted on antigen-specific responses. Thus, our data significantly enhance the understanding of graft dysfunction associated with chronic antibody-mediated rejection and provide the foundation for strategies to prolong renal allograft survival, based on regulation of interferon-γ production.


Asunto(s)
Comunicación Autocrina , Linfocitos B/inmunología , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Interferón gamma/inmunología , Isoanticuerpos/sangre , Trasplante de Riñón/efectos adversos , Riñón/inmunología , Células TH1/inmunología , Adulto , Área Bajo la Curva , Comunicación Autocrina/efectos de los fármacos , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , Biopsia , Distribución de Chi-Cuadrado , Enfermedad Crónica , Progresión de la Enfermedad , Ensayo de Immunospot Ligado a Enzimas , Femenino , Tasa de Filtración Glomerular , Rechazo de Injerto/sangre , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/fisiopatología , Supervivencia de Injerto , Histocompatibilidad , Humanos , Inmunosupresores/uso terapéutico , Interferón gamma/metabolismo , Ensayos de Liberación de Interferón gamma , Interleucina-10/inmunología , Interleucina-10/metabolismo , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/fisiopatología , Modelos Lineales , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Curva ROC , Factores de Riesgo , Transducción de Señal , Células TH1/efectos de los fármacos , Células TH1/metabolismo , Factores de Tiempo , Resultado del Tratamiento
5.
Lancet ; 386(10006): 1835-44, 2015 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-26343840

RESUMEN

BACKGROUND: Post-stroke pneumonia is associated with increased mortality and poor functional outcomes. This study assessed the effectiveness of antibiotic prophylaxis for reducing pneumonia in patients with dysphagia after acute stroke. METHODS: We did a prospective, multicentre, cluster-randomised, open-label controlled trial with masked endpoint assessment of patients older than 18 years with dysphagia after new stroke recruited from 48 stroke units in the UK, accredited and included in the UK National Stroke Audit. We excluded patients with contraindications to antibiotics, pre-existing dysphagia, or known infections, or who were not expected to survive beyond 14 days. We randomly assigned the units (1:1) by computer to give either prophylactic antibiotics for 7 days plus standard stroke unit care or standard stroke unit care only to patients clustered in the units within 48 h of stroke onset. We did the randomisation with minimisation to stratify for number of admissions and access to specialist care. Patient and staff who did the assessments and analyses were masked to stroke unit allocation. The primary outcome was post-stroke pneumonia in the first 14 days, assessed with both a criteria-based, hierarchical algorithm and by physician diagnosis in the intention-to-treat population. Safety was also analysed by intention to treat. This trial is closed to new participants and is registered with isrctn.com, number ISRCTN37118456. FINDINGS: Between April 21, 2008, and May 17, 2014, we randomly assigned 48 stroke units (and 1224 patients clustered within the units) to the two treatment groups: 24 to antibiotics and 24 to standard care alone (control). 11 units and seven patients withdrew after randomisation before 14 days, leaving 1217 patients in 37 units for the intention-to-treat analysis (615 patients in the antibiotics group, 602 in control). Prophylactic antibiotics did not affect the incidence of algorithm-defined post-stroke pneumonia (71 [13%] of 564 patients in antibiotics group vs 52 [10%] of 524 in control group; marginal adjusted odds ratio [OR] 1·21 [95% CI 0·71-2·08], p=0·489, intraclass correlation coefficient [ICC] 0·06 [95% CI 0·02-0·17]. Algorithm-defined post-stroke pneumonia could not be established in 129 (10%) patients because of missing data. Additionally, we noted no differences in physician-diagnosed post-stroke pneumonia between groups (101 [16%] of 615 patients vs 91 [15%] of 602, adjusted OR 1·01 [95% CI 0·61-1·68], p=0·957, ICC 0·08 [95% CI 0·03-0·21]). The most common adverse events were infections unrelated to post-stroke pneumonia (mainly urinary tract infections), which were less frequent in the antibiotics group (22 [4%] of 615 vs 45 [7%] of 602; OR 0·55 [0·32-0·92], p=0·02). Diarrhoea positive for Clostridium difficile occurred in two patients (<1%) in the antibiotics group and four (<1%) in the control group, and meticillin-resistant Staphylococcus aureus colonisation occurred in 11 patients (2%) in the antibiotics group and 14 (2%) in the control group. INTERPRETATION: Antibiotic prophylaxis cannot be recommended for prevention of post-stroke pneumonia in patients with dysphagia after stroke managed in stroke units. FUNDING: UK National Institute for Health Research.


Asunto(s)
Profilaxis Antibiótica/métodos , Trastornos de Deglución/complicaciones , Neumonía por Aspiración/prevención & control , Accidente Cerebrovascular/complicaciones , Enfermedad Aguda , Anciano , Antibacterianos/uso terapéutico , Trastornos de Deglución/etiología , Femenino , Humanos , Masculino , Neumonía por Aspiración/etiología , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
6.
Br J Psychiatry ; 208(6): 539-47, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26989096

RESUMEN

BACKGROUND: Twin studies have lacked statistical power to apply advanced genetic modelling techniques to the search for cognitive endophenotypes for bipolar disorder. AIMS: To quantify the shared genetic variability between bipolar disorder and cognitive measures. METHOD: Structural equation modelling was performed on cognitive data collected from 331 twins/siblings of varying genetic relatedness, disease status and concordance for bipolar disorder. RESULTS: Using a parsimonious AE model, verbal episodic and spatial working memory showed statistically significant genetic correlations with bipolar disorder (rg = |0.23|-|0.27|), which lost statistical significance after covarying for affective symptoms. Using an ACE model, IQ and visual-spatial learning showed statistically significant genetic correlations with bipolar disorder (rg = |0.51|-|1.00|), which remained significant after covarying for affective symptoms. CONCLUSIONS: Verbal episodic and spatial working memory capture a modest fraction of the bipolar diathesis. IQ and visual-spatial learning may tap into genetic substrates of non-affective symptomatology in bipolar disorder.


Asunto(s)
Trastorno Bipolar/genética , Disfunción Cognitiva/genética , Endofenotipos , Trastornos de la Memoria/genética , Memoria Episódica , Modelos Genéticos , Adolescente , Adulto , Anciano , Trastorno Bipolar/fisiopatología , Disfunción Cognitiva/fisiopatología , Femenino , Humanos , Masculino , Trastornos de la Memoria/fisiopatología , Memoria a Corto Plazo/fisiología , Persona de Mediana Edad , Hermanos , Memoria Espacial/fisiología , Gemelos , Adulto Joven
7.
Kidney Int ; 88(3): 560-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25830760

RESUMEN

We explored how B-lymphocytes influence in vitro T-cell alloresponses in patients with antibody-mediated rejection (AMR), testing whether B-cells would be preferentially involved in this group of patients. Peripheral blood mononuclear cells were collected from 65 patients having biopsy: 14 patients with AMR and 5 with no pathology on protocol; 38 with AMR and 8 with nonimmunologic damage on 'for cause'. Using enzyme-linked immunosorbent spot assays, we found interferon-γ production by indirect allorecognition in 45 of 119 total samples from the 65 patients. B-cells preferentially processed and presented donor alloantigens in samples from AMR patients. In a further 25 samples, B-cell-dependent allo-specific reactivity was shown by depletion of CD25(+) cells and these individuals had higher percentages of CD4CD25hi cells. In 21 samples, reactivity was shown by depletion of CD19(+) cells, associated with polarized cytokine production toward IL-10 after polyclonal activation by IgG/IgM. Overall, this shows a significant contribution by B-cells to indirect donor-specific T-cell reactivity in vitro in patients with AMR. Active suppression by distinct phenotypes of T- or B-cells in approximately half of the patients indicates that chronic AMR is not characterized by a universal loss of immune regulation. Thus, stratified approaches that accommodate the heterogeneity of cell-mediated immunity might be beneficial to treat graft dysfunction.


Asunto(s)
Linfocitos B/inmunología , Comunicación Celular , Rechazo de Injerto/inmunología , Inmunidad Humoral , Trasplante de Riñón/efectos adversos , Riñón/inmunología , Linfocitos T/inmunología , Linfocitos B/metabolismo , Biopsia , Células Cultivadas , Enfermedad Crónica , Ensayo de Immunospot Ligado a Enzimas , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/metabolismo , Humanos , Inmunofenotipificación , Interferón gamma/inmunología , Interferón gamma/metabolismo , Ensayos de Liberación de Interferón gamma , Isoanticuerpos/inmunología , Isoanticuerpos/metabolismo , Isoantígenos/inmunología , Activación de Linfocitos , Fenotipo , Linfocitos T/metabolismo , Resultado del Tratamiento
8.
Twin Res Hum Genet ; 16(1): 302-6, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23046559

RESUMEN

The Murcia Twin Registry (MTR) was created in 2006, under the auspices of the University of Murcia and the regional Health Authority, aiming to develop a research resource in Spain intended to stimulate current research and new investigation on the analysis of genetic factors related to health and health-related behaviors. The MTR development strategy was designed as a step-by-step process. Initially, it was focused on women's health but nowadays it includes males and opposite-sex twins. The database comprises 2,281 participants born between 1940 and 1966 in the region of Murcia, in Spain. There have been three waves of data collection and today the MTR databases include questionnaire and anthropometric data as well as biological samples. The current main areas of research interest are health and health-related behaviors, including lifestyle, health promotion, and quality of life. Future short-term development points to the completion of the biobank and continuing the collection of longitudinal data.


Asunto(s)
Investigación Biomédica , Enfermedades en Gemelos/epidemiología , Sistema de Registros , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genética , Adulto , Anciano , Bancos de Muestras Biológicas , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Selección de Paciente , Proyectos de Investigación , España/epidemiología
9.
J Vasc Surg ; 53(4): 1039-43, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21215562

RESUMEN

OBJECTIVE: The number of elderly patients needing hemodialysis is constantly increasing year by year. Elderly patients with end-stage renal failure represent a challenge for the surgeons who create vascular accesses. The aim of this study was to analyze the outcome of conduit creation in the elderly in our institution and to compare it with the outcome of a cohort of patients aged <65 years. METHODS: The study was performed retrospectively on prospectively collected data. The study period was between January 1, 2000, and December 31, 2006. We identified first attempts at conduit creations, including arteriovenous fistulas (AVFs) and grafts, in elderly patients (aged ≥65 years) who were allocated to group A, and in nonelderly patients (<65 years) who were allocated to group B. Subsequent attempts at conduit creations in the same patient were omitted from the data set. RESULTS: There were 246 first AVFs in group A and 89 in group B. At a mean follow-up of 25.46 months (SD, 18.93 months), the primary patency (PP) rate of all AVFs was 70% in group A and 68% in group B (P = .75). The assisted PP rate was 73% in group A and 77% in group B (P = .4). The secondary patency (SP) rate was 73% in group A and 79% in group B (P = .9). Also, the differences in the 12-month cumulative patency rates (including PP, assisted PP, and SP) in the two groups (65% vs 60%) were not significant. At a mean follow-up of 25 months, death with a functioning conduit occurred at the same rate in both groups (56% and 54%), and mean conduit survival did not differ according to age (516 and 511 days). The incidence of failure to mature was higher in group A (6.1% vs 1.1%, P = .03). Patency rates for different types of conduits were similar between the two groups, although polytetrafluoroethylene grafts had a higher cumulative patency in group A (94% vs 69%; P = .05). The rate of procedures to salvage conduits was 2.5% in group A vs 10.1% in group B. Mean hospital stay for group A and group B was 3.2 days. CONCLUSIONS: In our experience, the creation of permanent hemodialysis access in the elderly with AVF is not only possible but also proved to have a short hospital stay, high patency rates, and an acceptable rate of further intervention.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Implantación de Prótesis Vascular , Diálisis Renal , Extremidad Superior/irrigación sanguínea , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Derivación Arteriovenosa Quirúrgica/efectos adversos , Implantación de Prótesis Vascular/efectos adversos , Distribución de Chi-Cuadrado , Femenino , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/cirugía , Humanos , Estimación de Kaplan-Meier , Tiempo de Internación , Londres , Masculino , Persona de Mediana Edad , Selección de Paciente , Reoperación , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular , Adulto Joven
10.
Behav Genet ; 41(2): 211-22, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21086156

RESUMEN

Individual differences in adolescent exercise behavior are to a large extent explained by shared environmental factors. The aim of this study was to explore to what extent this shared environment represents effects of cultural transmission of parents to their offspring, generation specific environmental effects or assortative mating. Survey data on leisure-time exercise behavior were available from 3,525 adolescent twins and their siblings (13-18 years) and 3,138 parents from 1,736 families registered at the Netherlands Twin Registry. Data were also available from 5,471 adult twins, their siblings and spouses similar in age to the parents. Exercise participation (No/Yes, using a cut-off criterion of 4 metabolic equivalents and 60 min weekly) was based on questions on type, frequency and duration of exercise. A model to analyze dichotomous data from twins, siblings and parents including differences in variance decomposition across sex and generation was developed. Data from adult twins and their spouses were used to investigate the causes of assortative mating (correlation between spouses = 0.41, due to phenotypic assortment). The heritability of exercise in the adult generation was estimated at 42%. The shared environment for exercise behavior in adolescents mainly represents generation specific shared environmental influences that seem somewhat more important in explaining familial clustering in girls than in boys (52 versus 41%). A small effect of vertical cultural transmission was found for boys only (3%). The remaining familial clustering for exercise behavior was explained by additive genetic factors (42% in boys and 36% in girls). Future studies on adolescent exercise behavior should focus on identification of the generation specific environmental factors.


Asunto(s)
Características Culturales , Ejercicio Físico , Adolescente , Adulto , Anciano , Actitud Frente a la Salud , Ambiente , Salud de la Familia , Femenino , Humanos , Estilo de Vida , Masculino , Persona de Mediana Edad , Modelos Genéticos , Países Bajos , Padres , Factores Sexuales
11.
Behav Genet ; 40(4): 480-94, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20145989

RESUMEN

Social isolation and loneliness in humans have been associated with physical and psychological morbidity, as well as mortality. This study aimed to assess the etiology of individual differences in feelings of loneliness. The genetic architecture of loneliness was explored in an extended twin-family design including 8,683 twins, siblings and parents from 3,911 families. In addition, 917 spouses of twins participated. The presence of assortative mating, genetic non-additivity, vertical cultural transmission, genotype-environment (GE) correlation and interaction was modeled. GE interaction was considered for several demographic characteristics. Results showed non-random mating for loneliness. We confirmed that loneliness is moderately heritable, with a significant contribution of non-additive genetic variation. There were no effects of vertical cultural transmission. With respect to demographic characteristics, results indicated that marriage, having offspring, more years of education, and a higher number of siblings are associated with lower levels of loneliness. Interestingly, these effects tended to be stronger for men than women. There was little evidence of changes in genetic architecture as a function of these characteristics. We conclude that the genetic architecture of loneliness points to non-additive genetic influences, suggesting it may be a trait that was not neutral to selection in our evolutionary past. Sociodemographic factors that influence the prevalence of loneliness do not affect its genetic architecture.


Asunto(s)
Genotipo , Patrón de Herencia/genética , Soledad/psicología , Fenotipo , Medio Social , Características Culturales , Femenino , Humanos , Masculino , Modelos Psicológicos , Modelos Estadísticos , Sistema de Registros , Gemelos
12.
Twin Res Hum Genet ; 13(2): 143-62, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20397745

RESUMEN

Adolescents' evaluations of family functioning may have a significant impact on their subjective well-being and adjustment. The aim of the study was to investigate the degree to which genetic and environmental influences affect variation in evaluations of general family functioning, family conflict, and quality of life and the overlap between them. We assessed whether genetic and environmental influences are moderated by parental divorce by analyzing self-report data from 6,773 adolescent twins and their non-twin siblings. Genetic, shared, and nonshared environmental influences accounted for variation in general family functioning and family conflict, with genetic influences being relatively more important in girls than boys in general family functioning. Genetic and nonshared environmental influences accounted for variation in quality of life, with genetic influences being relatively more important in girls. Evidence was found for interaction between genetic factors and parental divorce: genetic influence on general family functioning was larger in participants from divorced families. The overlap between general family functioning and quality of life, and family conflict and quality of life was accounted for the largest part by genetic effects, with nonshared environmental effects accounting for the remaining part. By examining the data from monozygotic twins, we found evidence for interaction between genotype and nonshared, non-measured, environmental influences on evaluations of general family functioning, family conflict, and quality of life.


Asunto(s)
Divorcio , Familia , Padres , Calidad de Vida , Adolescente , Conducta del Adolescente/psicología , Femenino , Humanos , Masculino , Modelos Estadísticos , Relaciones Padres-Hijo , Responsabilidad Parental , Hermanos , Encuestas y Cuestionarios , Gemelos Dicigóticos/genética , Gemelos Monocigóticos/genética
13.
EBioMedicine ; 58: 102899, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32707447

RESUMEN

BACKGROUND: Kidney transplant recipients (KTRs) with "operational tolerance" (OT) maintain a functioning graft without immunosuppressive (IS) drugs, thus avoiding treatment complications. Nevertheless, IS drugs can influence gene-expression signatures aiming to identify OT among treated KTRs. METHODS: We compared five published signatures of OT in peripheral blood samples from 18 tolerant, 183 stable, and 34 chronic rejector KTRs, using gene-expression levels with and without adjustment for IS drugs and regularised logistic regression. FINDINGS: IS drugs explained up to 50% of the variability in gene-expression and 20-30% of the variability in the probability of OT predicted by signatures without drug adjustment. We present a parsimonious consensus gene-set to identify OT, derived from joint analysis of IS-drug-adjusted expression of five published signature gene-sets. This signature, including CD40, CTLA4, HSD11B1, IGKV4-1, MZB1, NR3C2, and RAB40C genes, showed an area under the curve 0⋅92 (95% confidence interval 0⋅88-0⋅94) in cross-validation and 0⋅97 (0⋅93-1⋅00) in six months follow-up samples. INTERPRETATION: We advocate including adjustment for IS drug therapy in the development stage of gene-expression signatures of OT to reduce the risk of capturing features of treatment, which could be lost following IS drug minimisation or withdrawal. Our signature, however, would require further validation in an independent dataset and a biomarker-led trial. FUNDING: FP7-HEALTH-2012-INNOVATION-1 [305147:BIO-DrIM] (SC,IR-M,PM,DSt); MRC [G0801537/ID:88245] (MPH-F); MRC [MR/J006742/1] (IR-M); Guy's&StThomas' Charity [R080530]&[R090782]; CONICYT-Bicentennial-Becas-Chile (EN-L); EU:FP7/2007-2013 [HEALTH-F5-2010-260687: The ONE Study] (MPH-F); Czech Ministry of Health [NV19-06-00031] (OV); NIHR-BRC Guy's&StThomas' NHS Foundation Trust and KCL (SC); UK Clinical Research Networks [portfolio:7521].


Asunto(s)
Perfilación de la Expresión Génica/métodos , Redes Reguladoras de Genes , Rechazo de Injerto/prevención & control , Inmunosupresores/uso terapéutico , Tolerancia al Trasplante , Adulto , Anciano , Estudios de Casos y Controles , Consenso , Femenino , Redes Reguladoras de Genes/efectos de los fármacos , Rechazo de Injerto/genética , Humanos , Inmunosupresores/farmacología , Trasplante de Riñón/efectos adversos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa
14.
EBioMedicine ; 41: 571-583, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30833191

RESUMEN

BACKGROUND: Acute T-cell mediated rejection (TCMR) is usually indicated by alteration in serum-creatinine measurements when considerable transplant damage has already occurred. There is, therefore, a need for non-invasive early detection of immune signals that would precede the onset of rejection, prior to transplant damage. METHODS: We examined the RT-qPCR expression of 22 literature-based genes in peripheral blood samples from 248 patients in the Kidney Allograft Immune Biomarkers of Rejection Episodes (KALIBRE) study. To account for post-transplantation changes unrelated to rejection, we generated time-adjusted gene-expression residuals from linear mixed-effects models in stable patients. To select genes, we used penalised logistic regression based on 27 stable patients and 27 rejectors with biopsy-proven T-cell-mediated rejection, fulfilling strict inclusion/exclusion criteria. We validated this signature in i) an independent group of stable patients and patients with concomitant T-cell and antibody-mediated-rejection, ii) patients from an independent study, iii) cross-sectional pre-biopsy samples from non-rejectors and iv) longitudinal follow-up samples covering the first post-transplant year from rejectors, non-rejectors and stable patients. FINDINGS: A parsimonious TCMR-signature (IFNG, IP-10, ITGA4, MARCH8, RORc, SEMA7A, WDR40A) showed cross-validated area-under-ROC curve 0.84 (0.77-0.88) (median, 2.5th-97.5th centile of fifty cross-validation cycles), sensitivity 0.67 (0.59-0.74) and specificity 0.85 (0.75-0.89). The estimated probability of TCMR increased seven weeks prior to the diagnostic biopsy and decreased after treatment. Gene expression in all patients showed pronounced variability, with up to 24% of the longitudinal samples in stable patients being TCMR-signature positive. In patients with borderline changes, up to 40% of pre-biopsy samples were TCMR-signature positive. INTERPRETATION: Molecular marker alterations in blood emerge well ahead of the time of clinically overt TCMR. Monitoring a TCMR-signature in peripheral blood could unravel T-cell-related pro-inflammatory activity and hidden immunological processes. This additional information could support clinical management decisions in cases of patients with stable but poor kidney function or with inconclusive biopsy results.


Asunto(s)
Rechazo de Injerto/etiología , Trasplante de Riñón , Linfocitos T/inmunología , Adolescente , Adulto , Anciano , Antígenos CD/genética , Área Bajo la Curva , Estudios Transversales , Femenino , Proteínas Ligadas a GPI/genética , Humanos , Interferón gamma/genética , Trasplante de Riñón/efectos adversos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Poliomavirus/patogenicidad , Curva ROC , Semaforinas/genética , Linfocitos T/metabolismo , Transcriptoma , Adulto Joven
15.
Trials ; 20(1): 476, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31383029

RESUMEN

BACKGROUND: Chronic rejection is the single biggest cause of premature kidney graft failure. HLA antibodies (Ab) are an established prognostic biomarker for premature graft failure so there is a need to test whether treatment decisions based on the presence of the biomarker can alter prognosis. The Optimised TacrolimuS and MMF for HLA Antibodies after Renal Transplantation (OuTSMART) trial combines two elements. Firstly, testing whether a routine screening programme for HLA Ab in all kidney transplant recipients is useful by comparing blinding versus unblinding of HLA Ab status. Secondly, for those found to be HLA Ab+, testing whether the introduction of a standard optimisation treatment protocol can reduce graft failure rates. METHODS: OuTSMART is a prospective, open-labelled, randomised biomarker-based strategy (hybrid) trial, with two arms stratified by biomarker (HLA Ab) status. The primary outcome was amended from graft failure rates at 3 years to time to graft failure to increase power and require fewer participants to be recruited. Length of follow-up subsequently is variable, with all participants followed up for at least 43 months up to a maximum of 89 months. The primary outcome will be analysed using Cox regression adjusting for stratification factors. Analyses will be according to the intention-to-treat using all participants as randomised. Outcomes will be analysed comparing standard care versus biomarker-led care groups within the HLA Ab+ participants (including those who become HLA Ab+ through re-screening) as well as between HLA-Ab-unblinded and HLA-Ab-blinded groups using all participants. DISCUSSION: Changes to the primary outcome permit recruitment of fewer participants to achieve the same statistical power. Pre-stating the statistical analysis plan guards against changes to the analysis methods at the point of analysis that might otherwise introduce bias through knowledge of the data. Any deviations from the analysis plan will be justified in the final report. TRIAL REGISTRATION: ISRCTN registry, ID: ISRCTN46157828 . Registered on 26 March 2013; EudraCT 2012-004308-36 . Registered on 10 December 2012.


Asunto(s)
Interpretación Estadística de Datos , Rechazo de Injerto/complicaciones , Antígenos HLA/inmunología , Isoanticuerpos/inmunología , Trasplante de Riñón/efectos adversos , Estudios Multicéntricos como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Enfermedad Crónica , Humanos , Evaluación de Resultado en la Atención de Salud , Estudios Prospectivos , Proyectos de Investigación , Tamaño de la Muestra
16.
Front Aging Neurosci ; 10: 51, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29556190

RESUMEN

Parkinson's disease (PD) shows high heterogeneity with regard to the underlying molecular pathogenesis involving multiple pathways and mechanisms. Diagnosis is still challenging and rests entirely on clinical features. Thus, there is an urgent need for robust diagnostic biofluid markers. Untargeted metabolomics allows establishing low-molecular compound biomarkers in a wide range of complex diseases by the measurement of various molecular classes in biofluids such as blood plasma, serum, and cerebrospinal fluid (CSF). Here, we applied untargeted high-resolution mass spectrometry to determine plasma and CSF metabolite profiles. We semiquantitatively determined small-molecule levels (≤1.5 kDa) in the plasma and CSF from early PD patients (disease duration 0-4 years; n = 80 and 40, respectively), and sex- and age-matched controls (n = 76 and 38, respectively). We performed statistical analyses utilizing partial least square and random forest analysis with a 70/30 training and testing split approach, leading to the identification of 20 promising plasma and 14 CSF metabolites. These metabolites differentiated the test set with an AUC of 0.8 (plasma) and 0.9 (CSF). Characteristics of the metabolites indicate perturbations in the glycerophospholipid, sphingolipid, and amino acid metabolism in PD, which underscores the high power of metabolomic approaches. Further studies will enable to develop a potential metabolite-based biomarker panel specific for PD.

17.
Mol Cell Endocrinol ; 473: 205-216, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-29427591

RESUMEN

Steroid conversion (HSD11B1, HSD11B2, H6PD) and receptor genes (NR3C1, NR3C2) were examined in kidney-transplant recipients with "operational tolerance" and chronic rejection (CR), independently and within the context of 88 tolerance-associated genes. Associations with cellular types were explored. Peripheral whole-blood gene-expression levels (RT-qPCR-based) and cell counts were adjusted for immunosuppressant drug intake. Tolerant (n = 17), stable (n = 190) and CR patients (n = 37) were compared. Healthy controls (n = 14) were used as reference. The anti-inflammatory glucocorticoid receptor (NR3C1) and the cortisol-activating HSD11B1 and H6PD genes were up-regulated in CR and were lowest in tolerant patients. The pro-inflammatory mineralocorticoid gene (NR3C2) was downregulated in stable and CR patients. NR3C1 was associated with neutrophils and NR3C2 with T-cells. Steroid conversion and receptor genes, alone, enabled classification of tolerant patients and were major contributors to gene-expression signatures of both, tolerance and CR, alongside known tolerance-associated genes, revealing a key role of steroid regulation and response in kidney transplantation.


Asunto(s)
Rechazo de Injerto/etiología , Rechazo de Injerto/inmunología , Tolerancia Inmunológica , Trasplante de Riñón/efectos adversos , Esteroides/farmacología , Área Bajo la Curva , Recuento de Células , Enfermedad Crónica , Regulación de la Expresión Génica/efectos de los fármacos , Rechazo de Injerto/genética , Humanos , Tolerancia Inmunológica/efectos de los fármacos , Tolerancia Inmunológica/genética , Análisis Multivariante , Prednisolona/administración & dosificación , Prednisolona/farmacología , Probabilidad , Isoformas de Proteínas/metabolismo , Receptores de Glucocorticoides/metabolismo , Análisis de Regresión , Regulación hacia Arriba/efectos de los fármacos
18.
Trials ; 18(1): 255, 2017 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-28587616

RESUMEN

BACKGROUND: Delayed graft function (DGF) is traditionally defined as the requirement for dialysis during the first week after transplantation. DGF is a common complication of renal transplantation, and it negatively affects short- and long-term graft outcomes. Ischaemia reperfusion injury (IRI) is a prime contributor to the development of DGF. It is well established that complement system activation plays a pivotal role in the pathogenesis of IRI. Mirococept is a highly effective complement inhibitor that can be administered ex vivo to the donor kidney just before transplantation. Preclinical and clinical evidence suggests that Mirococept inhibits inflammatory responses that follow IRI. The EMPIRIKAL trial (REC 12/LO/1334) aims to evaluate the efficacy of Mirococept in reducing the incidence of DGF in cadaveric renal transplantation. METHODS/DESIGN: EMPIRIKAL is a multicentre double-blind randomised case-control trial designed to test the superiority of Mirococept in the prevention of DGF in cadaveric renal allografts, as compared to standard cold perfusion fluid (Soltran®). Patients will be randomised to Mirococept or placebo (Pbo) and will be enrolled in cohorts of N = 80 with a maximum number of 7 cohorts. The first cohort will be randomised to 10 mg of Mirococept or Pbo. After the completion of each cohort, an interim analysis will be carried out in order to evaluate the dose allocation for the next cohort (possible doses: 5-25 mg). Immunosuppression therapy, antibiotic and antiviral prophylaxis will be administered as per local centre protocols. The enrolment will take approximately 24 months, and patients will be followed for 12 months. The primary endpoint is DGF, defined as the requirement for dialysis during the first week after transplantation. Secondary endpoints include duration of DGF, functional DGF, renal function at 12 months, acute rejection episodes at 6 and 12 months, primary non-function and time of hospital stay on first admission and in the first year following transplant. Safety evaluation will include the monitoring of laboratory data and the recording of all adverse events. DISCUSSION: The EMPIRIKAL trial is the first study to evaluate the efficacy of an ex vivo administered complement inhibitor (Mirococept) in preventing DGF in cadaveric human renal transplantation. Mirococept has a unique 'cytotopic' property that permits its retention in the organ microvasculature. TRIAL REGISTRATION: ISRCTN registry, ISRCTN49958194 . Registered on 3 August 2012.


Asunto(s)
Inactivadores del Complemento/administración & dosificación , Funcionamiento Retardado del Injerto/prevención & control , Trasplante de Riñón/efectos adversos , Fragmentos de Péptidos/administración & dosificación , Receptores de Complemento 3b/química , Daño por Reperfusión/prevención & control , Aloinjertos , Protocolos Clínicos , Inactivadores del Complemento/efectos adversos , Funcionamiento Retardado del Injerto/diagnóstico , Funcionamiento Retardado del Injerto/inmunología , Método Doble Ciego , Esquema de Medicación , Humanos , Fragmentos de Péptidos/efectos adversos , Fragmentos de Péptidos/química , Daño por Reperfusión/diagnóstico , Daño por Reperfusión/inmunología , Proyectos de Investigación , Factores de Tiempo , Resultado del Tratamiento , Reino Unido
19.
Trials ; 15: 30, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24447519

RESUMEN

BACKGROUND: Renal transplantation is the best treatment for kidney failure, in terms of length and quality of life and cost-effectiveness. However, most transplants fail after 10 to 12 years, consigning patients back onto dialysis. Damage by the immune system accounts for approximately 50% of failing transplants and it is possible to identify patients at risk by screening for the presence of antibodies against human leukocyte antigens. However, it is not clear how best to treat patients with antibodies. This trial will test a combined screening and treatment protocol in renal transplant recipients. METHODS/DESIGN: Recipients>1 year post-transplantation, aged 18 to 70 with an estimated glomerular filtration rate>30 mL/min will be randomly allocated to blinded or unblinded screening arms, before being screened for the presence of antibodies. In the unblinded arm, test results will be revealed. Those with antibodies will have biomarker-led care, consisting of a change in their anti-rejection drugs to prednisone, tacrolimus and mycophenolate mofetil. In the blinded arm, screening results will be double blinded and all recruits will remain on current therapy (standard care). In both arms, those without antibodies will be retested every 8 months for 3 years. The primary outcome is the 3-year kidney failure rate for the antibody-positive recruits, as measured by initiation of long-term dialysis or re-transplantation, predicted to be approximately 20% in the standard care group but <10% in biomarker-led care. The secondary outcomes include the rate of transplant dysfunction, incidence of infection, cancer and diabetes mellitus, an analysis of adherence with medication and a health economic analysis of the combined screening and treatment protocol. Blood samples will be collected and stored every 4 months and will form the basis of separately funded studies to identify new biomarkers associated with the outcomes. DISCUSSION: We have evidence that the biomarker-led care regime will be effective at preventing graft dysfunction and expect this to feed through to graft survival. This trial will confirm the benefit of routine screening and lead to a greater understanding of how to keep kidney transplants working longer. TRIAL REGISTRATION: Current Controlled Trials ISRCTN46157828.


Asunto(s)
Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Antígenos HLA/inmunología , Prueba de Histocompatibilidad , Histocompatibilidad , Inmunosupresores/uso terapéutico , Isoanticuerpos/sangre , Trasplante de Riñón/efectos adversos , Proyectos de Investigación , Biomarcadores/sangre , Enfermedad Crónica , Protocolos Clínicos , Análisis Costo-Beneficio , Método Doble Ciego , Quimioterapia Combinada , Rechazo de Injerto/economía , Rechazo de Injerto/inmunología , Costos de la Atención en Salud , Prueba de Histocompatibilidad/economía , Humanos , Inmunosupresores/economía , Trasplante de Riñón/economía , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores de Tiempo , Resultado del Tratamiento , Reino Unido
20.
J Pain Symptom Manage ; 44(2): 229-38, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22578312

RESUMEN

CONTEXT: Renal transplantation is gold standard care in end-stage kidney disease, but little is known about symptom prevalence in transplanted patients. OBJECTIVES: This study assesses symptom prevalence in this population. METHODS: This was a U.K.-based, cross-sectional symptom survey of end-stage kidney disease patients transplanted more than one year previously. Patient-reported data were collected using the renal Patient Outcome Scale. Demographic/clinical data also were collected, including estimated glomerular filtration rate (eGFR), renal diagnosis, and comorbidity. RESULTS: One hundred ten patients participated; mean age was 47 years (SD 13.6), and mean eGFR was 46 mL/min (SD 16.8, range 14-101). Symptom burden was high, with a mean of seven symptoms, but marked variance (SD 5.2, range 0-22). The most prevalent symptoms were weakness (56%, 95% CI 47-65), difficulty sleeping (46%, 95% CI 37-56), dyspnea (42%, 95% CI 33-51), feeling anxious (36%, 95% CI 28-46), and drowsiness (36%, 95% CI 28-46). Certain symptoms-weakness, difficulty sleeping, dyspnea, and drowsiness-were commonly reported as severe. A significant inverse relationship between renal function, as measured by eGFR, and number of symptoms (P<0.05) emerged. CONCLUSION: For renal transplant recipients, symptom burden is similar to dialysis, although with less pain, anorexia, and immobility. Routine symptom assessment should be undertaken in transplant patients to identify these often undisclosed symptoms.


Asunto(s)
Fallo Renal Crónico/cirugía , Trasplante de Riñón/psicología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/psicología , Adulto , Anciano , Estudios Transversales , Femenino , Tasa de Filtración Glomerular , Humanos , Pruebas de Función Renal , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad , Dolor/etiología , Dolor/psicología , Resultado del Tratamiento , Reino Unido , Adulto Joven
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