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Despite widespread interest and substantial investment in the adoption of sensor-based digital health technologies (sDHTs) for remote data capture in drug development trials, no drug has been approved based on an sDHT-derived primary endpoint in the United States (US). One reason for this lack of advancement is the complexity of obtaining regulatory endorsement for those endpoints within current US regulatory pathways. The goal of our review is to describe the two choices currently available to pharmaceutical study Sponsors: (i) they may navigate the traditional route of compiling the evidence to support the sDHT-derived endpoint in their investigational new drug (IND) application, requiring specific expertise and substantial resources; or (ii) they may navigate the drug development tool (DDT) pathway with the goal of qualifying their sDHT-derived endpoint as a biomarker or clinical outcome assessment applicable to a broader context of use (COU), either alone or as part of a partnership or consortium. We describe the nuances of each pathway; the evidentiary requirements for supporting an sDHT-derived endpoint and the technology used to capture it; and the impact that an sDHT's regulatory status may have on a Sponsor's decision to use it for data capture. By systematically comparing the IND and DDT pathways, our over-arching goals are to support the increasing deployment of sDHTs within the clinical research setting and help advance regulatory science in the field of digital medicine.
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Background: Digital measures offer an unparalleled opportunity to create a more holistic picture of how people who are patients behave in their real-world environments, thereby establishing a better connection between patients, caregivers, and the clinical evidence used to drive drug development and disease management. Reaching this vision will require achieving a new level of co-creation between the stakeholders who design, develop, use, and make decisions using evidence from digital measures. Summary: In September 2022, the second in a series of meetings hosted by the Swiss Federal Institute of Technology in Zürich, the Foundation for the National Institutes of Health Biomarkers Consortium, and sponsored by Wellcome Trust, entitled "Reverse Engineering of Digital Measures," was held in Zurich, Switzerland, with a broad range of stakeholders sharing their experience across four case studies to examine how patient centricity is essential in shaping development and validation of digital evidence generation tools. Key Messages: In this paper, we discuss progress and the remaining barriers to widespread use of digital measures for evidence generation in clinical development and care delivery. We also present key discussion points and takeaways in order to continue discourse and provide a basis for dissemination and outreach to the wider community and other stakeholders. The work presented here shows us a blueprint for how and why the patient voice can be thoughtfully integrated into digital measure development and that continued multistakeholder engagement is critical for further progress.
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Currently, no disease-modifying therapies are approved for osteoarthritis (OA) use. One obstacle to trial success in this field has been our existing endpoints' limited validity and responsiveness. To overcome this impasse, the Foundation for the NIH OA Biomarkers Consortium is focused on investigating biomarkers for a prognostic context of use for subsequent qualification through regulatory agencies. This narrative review describes this activity and the work underway, focusing on the PROGRESS OA study.
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Osteoartritis , Humanos , Osteoartritis/diagnóstico por imagen , Biomarcadores , PronósticoRESUMEN
Clinical safety findings remain one of the reasons for attrition of drug candidates during clinical development. Cardiovascular liabilities are not consistently detected in early-stage clinical trials and often become apparent when drugs are administered chronically for extended periods of time. Vital sign data collection outside of the clinic offers an opportunity for deeper physiological characterization of drug candidates and earlier safety signal detection. A working group representing expertise from biopharmaceutical and technology sectors, US Food and Drug Administration (FDA) public-private partnerships, academia, and regulators discussed and presented a remote cardiac monitoring case study at the FNIH Biomarkers Consortium Remote Digital Monitoring for Medical Product Development workshop to examine applicability of the biomarker qualification evidentiary framework by the FDA. This use case examined the components of the framework, including the statement of need, the context of use, the state of the evidence, and the benefit/risk profile. Examination of results from 2 clinical trials deploying 510(k)-cleared devices for remote cardiac data collection demonstrated the need for analytical and clinical validity irrespectively of the regulatory status of a device of interest, emphasizing the importance of data collection method assessment in the context of intended use. Additionally, collection of large amounts of ambulatory data also highlighted the need for new statistical methods and contextual information to enable data interpretation. A wider adoption of this approach for drug development purposes will require collaborations across industry, academia, and regulatory agencies to establish methodologies and supportive data sets to enable data interpretation and decision-making.
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BACKGROUND: Currently, 2 coprimary end points are used by health authorities to determine the effectiveness of therapeutic interventions in patients with Crohn's disease (CD): symptomatic remission (patient-reported outcome assessment) and endoscopic remission (ileocolonoscopy). However, there is lack of accepted biomarkers to facilitate regulatory decision-making in the development of novel therapeutics for the treatment of CD. METHODS: With support from the Helmsley Charitable Trust, Critical Path Institute formed the Crohn's Disease Biomarkers preconsortium (CDBpC) with members from the pharmaceutical industry, academia, and nonprofit organizations to evaluate the CD biomarker landscape. Biomarkers were evaluated based on biological relevance, availability of biomarker assays, and clinical validation data. RESULTS: The CDBpC identified the most critical need as pharmacodynamic/response biomarkers to monitor disease activity in response to therapeutic intervention. Fecal calprotectin (FC) and serum C-reactive protein (CRP) were identified as biomarkers ready for the regulatory qualification process. A number of exploratory biomarkers and potential panels of these biomarkers was also identified for additional development. Given the different factors involved in CD and disease progression, a combination of biomarkers, including inflammatory, tissue injury, genetic, and microbiome-associated biomarkers, will likely have the most utility. CONCLUSIONS: The primary focus of the Inflammatory Bowel Disease Regulatory Science Consortium will be development of exploratory biomarkers and the qualification of FC and CRP for IBD. The Inflammatory Bowel Disease Regulatory Science Consortium, focused on tools to support IBD drug development, will operate in the precompetitive space to share data, biological samples for biomarker testing, and assay information for novel biomarkers.
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Proteína C-Reactiva/análisis , Toma de Decisiones Clínicas/métodos , Enfermedad de Crohn/diagnóstico , Monitoreo de Drogas/métodos , Complejo de Antígeno L1 de Leucocito/análisis , Biomarcadores/análisis , Consenso , Enfermedad de Crohn/metabolismo , Enfermedad de Crohn/terapia , Descubrimiento de Drogas , Heces/química , Humanos , Reproducibilidad de los Resultados , Índice de Severidad de la EnfermedadAsunto(s)
Ensayos Clínicos como Asunto/métodos , Infecciones por Coronavirus , Monitoreo Fisiológico/métodos , Pandemias , Neumonía Viral , COVID-19 , Ensayos Clínicos como Asunto/legislación & jurisprudencia , Descubrimiento de Drogas , Reposicionamiento de Medicamentos , Determinación de Punto Final , HumanosRESUMEN
The Foundation for the National Institutes of Health (FNIH) Biomarkers Consortium (BC) is a public-private partnership that aims to facilitate drug development with biomarkers across a range of therapeutic areas. The BC is organized to address specific precompetitive biomarker projects, giving participating stakeholders a role in the design and conduct of projects and making the results freely public. Ultimately, the goals of the BC are to accelerate the development of new medicines, inform regulatory decision making, and improve patient care. Here, we describe how the BC works and briefly highlight its accomplishments. The BC has had many notable successful biomarker projects in the past 12 years, including I-SPY2, which has improved clinical trials and biomarker use for breast cancer, and an evidentiary framework for biomarker qualification. Recently, the BC has undergone a strategic expansion of its scope to include related drug development tools along the lines of the Biomarkers, Endpoints, and other Tools (BEST) resource.
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Biomarcadores/química , Desarrollo de Medicamentos/legislación & jurisprudencia , Descubrimiento de Drogas/legislación & jurisprudencia , National Institutes of Health (U.S.)/legislación & jurisprudencia , Toma de Decisiones , Humanos , Asociación entre el Sector Público-Privado/legislación & jurisprudencia , Estados Unidos , United States Food and Drug Administration/legislación & jurisprudenciaRESUMEN
OBJECTIVE: To investigate a targeted set of biochemical biomarkers as predictors of clinically relevant osteoarthritis (OA) progression. METHODS: Eighteen biomarkers were measured at baseline, 12â months (M) and 24â M in serum (s) and/or urine (u) of cases (n=194) from the OA initiative cohort with knee OA and radiographic and persistent pain worsening from 24 to 48â M and controls (n=406) not meeting both end point criteria. Primary analyses used multivariable regression models to evaluate the association between biomarkers (baseline and time-integrated concentrations (TICs) over 12 and 24â M, transposed to z values) and case status, adjusted for age, sex, body mass index, race, baseline radiographic joint space width, Kellgren-Lawrence grade, pain and pain medication use. For biomarkers with adjusted p<0.1, the c-statistic (area under the curve (AUC)), net reclassification index and the integrated discrimination improvement index were used to further select for hierarchical multivariable discriminative analysis and to determine the most predictive and parsimonious model. RESULTS: The 24â M TIC of eight biomarkers significantly predicted case status (ORs per 1 SD change in biomarker): sCTXI 1.28, sHA 1.22, sNTXI 1.25, uC2C-HUSA 1.27, uCTXII, 1.37, uNTXI 1.29, uCTXIα 1.32, uCTXIß 1.27. 24 M TIC of uCTXII (1.47-1.72) and uC2C-Human Urine Sandwich Assay (HUSA) (1.36-1.50) both predicted individual group status (pain worsening, joint space loss and their combination). The most predictive and parsimonious combinatorial model for case status consisted of 24 M TIC uCTXII, sHA and sNTXI (AUC 0.667 adjusted). Baseline uCTXII and uCTXIα both significantly predicted case status (OR 1.29 and 1.20, respectively). CONCLUSIONS: Several systemic candidate biomarkers hold promise as predictors of pain and structural worsening of OA.
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Biomarcadores/metabolismo , Osteoartritis de la Rodilla/diagnóstico , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Dimensión del Dolor/métodos , Valor Predictivo de las Pruebas , Pronóstico , Curva ROC , Radiografía , Sensibilidad y Especificidad , Índice de Severidad de la EnfermedadRESUMEN
One important component in determining the benefits and harms of medical interventions is the use of well-defined and reliable outcome assessments as endpoints in clinical trials. Improving endpoints can better define patient benefits, allowing more accurate assessment of drug efficacy and more informed benefit-vs-risk decisions; another potential plus is facilitating efficient trial design. Since our first report in 2012, 2 Foundation for the National Institutes of Health Biomarkers Consortium Project Teams have continued to develop outcome assessments for potential uses as endpoints in registrational clinical trials of community-acquired bacterial pneumonia and acute bacterial skin and skin structure infections. In addition, the teams have initiated similar work in the indications of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia. This report provides an update on progress to date in these 4 diseases.
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Antibacterianos/uso terapéutico , Ensayos Clínicos como Asunto , Determinación de Punto Final , Evaluación de Resultado en la Atención de Salud , Enfermedades Cutáneas Bacterianas/tratamiento farmacológico , Biomarcadores , Directrices para la Planificación en Salud , HumanosRESUMEN
PURPOSE: We describe the outcome of the Biomarkers Consortium CSF Proteomics Project (where CSF is cerebral spinal fluid), a public-private partnership of government, academia, nonprofit, and industry. The goal of this study was to evaluate a multiplexed MS-based approach for the qualification of candidate Alzheimer's disease (AD) biomarkers using CSF samples from the AD Neuroimaging Initiative. EXPERIMENTAL DESIGN: Reproducibility of sample processing, analytic variability, and ability to detect a variety of analytes of interest were thoroughly investigated. Multiple approaches to statistical analyses assessed whether panel analytes were associated with baseline pathology (mild cognitive impairment (MCI), AD) versus healthy controls or associated with progression for MCI patients, and included (i) univariate association analyses, (ii) univariate prediction models, (iii) exploratory multivariate analyses, and (iv) supervised multivariate analysis. RESULTS: A robust targeted MS-based approach for the qualification of candidate AD biomarkers was developed. The results identified several peptides with potential diagnostic or predictive utility, with the most significant differences observed for the following peptides for differentiating (including peptides from hemoglobin A, hemoglobin B, and superoxide dismutase) or predicting (including peptides from neuronal pentraxin-2, neurosecretory protein VGF (VGF), and secretogranin-2) progression versus nonprogression from MCI to AD. CONCLUSIONS AND CLINICAL RELEVANCE: These data provide potential insights into the biology of CSF in AD and MCI progression and provide a novel tool for AD researchers and clinicians working to improve diagnostic accuracy, evaluation of treatment efficacy, and early diagnosis.
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Enfermedad de Alzheimer/líquido cefalorraquídeo , Bioensayo/métodos , Biomarcadores/líquido cefalorraquídeo , Espectrometría de Masas/métodos , Neuroimagen/métodos , Anciano , Enfermedad de Alzheimer/patología , Secuencia de Aminoácidos , Apolipoproteínas E/líquido cefalorraquídeo , Área Bajo la Curva , Disfunción Cognitiva/líquido cefalorraquídeo , Disfunción Cognitiva/patología , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Datos de Secuencia Molecular , Péptidos/líquido cefalorraquídeo , Péptidos/química , Análisis de Componente Principal , Control de Calidad , Reproducibilidad de los Resultados , Estadística como AsuntoRESUMEN
Monocyte accumulation in renal allografts is associated with allograft dysfunction. As monocyte influx occurs acutely following reperfusion, we investigated the effect of ischemia-reperfusion injury (IRI) on monocyte colony stimulating factor (m-CSF), a key cytokine in monocyte recruitment. We hypothesized that renal tubule epithelial cells (RTECs) could produce m-CSF in response to IRI, which could in turn promote monocyte activation. Real time PCR was used to measure levels of intragraft m-CSF transcripts in patients during IRI and clinical rejection. Also, m-CSF production by RTECs following IRI simulation in vitro was measured using ELISA. Monocyte expression of CD40 and CD80 was then analyzed using flow cytometry following co-culture with supernatants of RTECs after IRI. Monocyte expression of CD40, CD80 and HLA-DR was then examined following treatment with rh-m-CSF (10, 36, and 100 ng/ml), as was monocyte size and granularity. We found that intragraft m-CSF transcription was significantly increased postreperfusion (P = 0.002) and during clinical rejection (P = 0.002). We also found that RTECs produced m-CSF in response to IRI in vitro (P = 0.036). Monocytes co-cultured with the supernatants of postischemic RTECs became activated as evidenced by increased expression of CD40 and CD80. Also, monocytes treated with recombinant m-CSF assumed an activated phenotype exhibiting increased size, granularity and expression of CD40, CD80, CD86, and HLA-DR, and demonstrating enhanced phagocytic activity. Taken together, we suggest that renal tubular cell derived m-CSF is a stimulus for monocyte activation and may be an important target for control of IRI-associated immune activation.
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Factores Estimulantes de Colonias/metabolismo , Células Epiteliales/citología , Trasplante de Riñón/métodos , Riñón/lesiones , Riñón/patología , Monocitos/metabolismo , Antígeno B7-1/biosíntesis , Antígenos CD40/biosíntesis , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo/métodos , Antígenos HLA-DR/metabolismo , Humanos , Sistema Inmunológico , Isquemia/patología , Modelos Biológicos , Monocitos/citología , ReperfusiónRESUMEN
BACKGROUND: Neonatal-onset multisystem inflammatory disease is characterized by fever, urticarial rash, aseptic meningitis, deforming arthropathy, hearing loss, and mental retardation. Many patients have mutations in the cold-induced autoinflammatory syndrome 1 (CIAS1) gene, encoding cryopyrin, a protein that regulates inflammation. METHODS: We selected 18 patients with neonatal-onset multisystem inflammatory disease (12 with identifiable CIAS1 mutations) to receive anakinra, an interleukin-1-receptor antagonist (1 to 2 mg per kilogram of body weight per day subcutaneously). In 11 patients, anakinra was withdrawn at three months until a flare occurred. The primary end points included changes in scores in a daily diary of symptoms, serum levels of amyloid A and C-reactive protein, and the erythrocyte sedimentation rate from baseline to month 3 and from month 3 until a disease flare. RESULTS: All 18 patients had a rapid response to anakinra, with disappearance of rash. Diary scores improved (P<0.001) and serum amyloid A (from a median of 174 mg to 8 mg per liter), C-reactive protein (from a median of 5.29 mg to 0.34 mg per deciliter), and the erythrocyte sedimentation rate decreased at month 3 (all P<0.001), and remained low at month 6. Magnetic resonance imaging showed improvement in cochlear and leptomeningeal lesions as compared with baseline. Withdrawal of anakinra uniformly resulted in relapse within days; retreatment led to rapid improvement. There were no drug-related serious adverse events. CONCLUSIONS: Daily injections of anakinra markedly improved clinical and laboratory manifestations in patients with neonatal-onset multisystem inflammatory disease, with or without CIAS1 mutations. (ClinicalTrials.gov number, NCT00069329 [ClinicalTrials.gov].).
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Inflamación/tratamiento farmacológico , Receptores de Interleucina-1/antagonistas & inhibidores , Sialoglicoproteínas/uso terapéutico , Urticaria/tratamiento farmacológico , Adolescente , Adulto , Proteínas Portadoras/genética , Niño , Preescolar , Femenino , Pérdida Auditiva/tratamiento farmacológico , Humanos , Inflamación/genética , Discapacidad Intelectual , Proteína Antagonista del Receptor de Interleucina 1 , Masculino , Meningitis/tratamiento farmacológico , Mutación , Proteína con Dominio Pirina 3 de la Familia NLR , Papiledema/tratamiento farmacológico , Sialoglicoproteínas/efectos adversos , SíndromeRESUMEN
BACKGROUND: Lung transplantation is severely limited by an inadequate supply of lungs from brain-dead donors. A potential solution is use of lungs from non-heart-beating donors (NHBDs) with retrieval at intervals after circulatory arrest and death. A warm ischemic period with concomitant reperfusion injury is a major limiting factor in the transplantation of lungs retrieved from NHBDs. We hypothesized that the administration of the nitric oxide-donor nitroglycerin to lungs from NHBDs would reduce ischemia-reperfusion injury by activation of guanylate cyclase to form guanosine 3',5'-cyclic monophosphate (cGMP). METHODS: An in situ isolated perfused rat lung model was used. Lungs were retrieved from rats at varying intervals after circulatory arrest and death. Lungs were either ventilated with O(2) in situ or not ventilated. Lungs were reperfused at intervals after death with Earle's solution with or without nitroglycerin (0.1 mg/ml). Lung ischemia-reperfusion injury was assessed by capillary filtration coefficient, wet-to-dry lung weight ratio, and pulmonary hemodynamics. Tissue levels of adenine nucleotides and cGMP concentrations were measured by high-performance liquid chromatography and enzyme immunoassay, respectively. RESULTS: Reperfusion with nitroglycerin decreased capillary filtration coefficient compared with reperfusion without nitroglycerin at all post-mortem ischemic times, irrespective of pre-harvest ventilation. cGMP levels increased significantly with nitroglycerin-reperfusion and attenuated decreases in high-energy adenine nucleotides. CONCLUSIONS: Reperfusion of lungs with nitroglycerin may facilitate safe lung transplantation from NHBDs by reducing capillary leak after reperfusion.
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Trasplante de Pulmón , Donantes de Óxido Nítrico/farmacología , Nitroglicerina/farmacología , Daño por Reperfusión/prevención & control , Animales , Cromatografía Líquida de Alta Presión , GMP Cíclico/metabolismo , Muerte , Activación Enzimática , Guanilato Ciclasa/metabolismo , Hemodinámica , Pulmón/irrigación sanguínea , Modelos Animales , Óxido Nítrico/fisiología , Ratas , Respiración Artificial , Donantes de TejidosRESUMEN
BACKGROUND: Perioperative lymphocyte depletion induces allograft tolerance in some animal models, but in humans has only been shown to reduce immunosuppressive requirements. Without maintenance immunosuppression, depleted human renal allograft recipients experience rejection characterized by infiltration of the allograft with monocytes and macrophages. T-cell depletion combined with a brief course of deoxyspergualin (DSG), a drug with inhibitory effects on monocytes and macrophages, induces tolerance in nonhuman primates. We therefore performed a trial to determine if lymphocyte depletion with alemtuzumab combined with DSG would induce tolerance in humans. METHODS: Five recipients of live donor kidneys were treated perioperatively with alemtuzumab and DSG and followed postoperatively without maintenance immunosuppression. Patients were evaluated clinically, by flow cytometry, and by protocol biopsies analyzed immunohistochemically and with real-time polymerase chain reaction. Results were compared to previously studied patients receiving alemtuzumab alone or standard immunosuppression. RESULTS: Despite profound T-cell depletion and therapeutic DSG dosing, all alemtuzumab/DSG patients developed reversible rejection that was similar in timing, histology, and transcriptional profile to that seen in patients treated with alemtuzumab alone. Chemokine expression was marked prior to and during rejections. CONCLUSIONS: We conclude that treatment with alemtuzumab and DSG does not induce tolerance in humans. Chemokine production may not be adequately suppressed using this approach.
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Anticuerpos Monoclonales/farmacología , Anticuerpos Antineoplásicos/farmacología , Guanidinas/farmacología , Inmunosupresores/farmacología , Trasplante de Riñón/inmunología , Depleción Linfocítica , Tolerancia al Trasplante/efectos de los fármacos , Adulto , Alemtuzumab , Anticuerpos Monoclonales Humanizados , Quimiocinas/genética , Quimiocinas/metabolismo , Creatina/sangre , Femenino , Rechazo de Injerto/metabolismo , Humanos , Riñón/citología , Riñón/inmunología , Riñón/fisiología , Ganglios Linfáticos/citología , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Linfocitos T/efectos de los fármacos , Transcripción GenéticaRESUMEN
We examined the role of CD40/CD40L interactions on the development of experimental autoimmune uveoretinitis (EAU), a cell-mediated, Th1-driven autoimmune disease that serves as a model for autoimmune uveitis in humans. EAU-susceptible B10.RIII mice immunized with the retinal autoantigen interphotoreceptor retinoid binding protein in CFA and treated with anti-CD40L Ab (MR1) had reduced incidence and severity of disease. Real-time PCR analysis revealed that the innate and adaptive responses of protected mice were reduced, without an obvious shift toward a Th2 cytokine profile. In contrast to some other reports, no evidence was found for regulatory cells in adoptive transfer experiments. To determine whether CD40L blockade resulted in long-term tolerance, mice protected by treatment with MR1 Ab were rechallenged for uveitis after circulating MR1 Ab levels dropped below the detection limit of ELISA. MR1-treated mice developed severe EAU and strong cellular responses to interphotoreceptor retinoid binding protein, comparable to those of control mice. These responses were higher than in mice that had not received the primary immunization concurrently with anti-CD40L treatment. We conclude that 1) CD40/CD40L interaction is required for EAU and its disruption prevents disease development; 2) CD40L blockade inhibits the innate response to immunization and reduces priming, but does not result in immune deviation; and 3) protection is dependent on persistence of anti-CD40L Abs, and long-term tolerance is not induced. Furthermore, immunological memory develops under cover of CD40L blockade causing enhanced responses upon rechallenge. Taken together, our data suggest that ongoing CD40/CD40L blockade might be required to maintain a therapeutic effect against uveitis.
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Enfermedades Autoinmunes/inmunología , Antígenos CD40/metabolismo , Ligando de CD40/metabolismo , Retinitis/inmunología , Uveítis/inmunología , Traslado Adoptivo , Animales , Anticuerpos Monoclonales/farmacología , Enfermedades Autoinmunes/prevención & control , Enfermedades Autoinmunes/terapia , Modelos Animales de Enfermedad , Proteínas del Ojo/inmunología , Humanos , Tolerancia Inmunológica , Inmunización , Memoria Inmunológica , Ratones , Retinitis/prevención & control , Retinitis/terapia , Proteínas de Unión al Retinol/inmunología , Uveítis/prevención & control , Uveítis/terapiaRESUMEN
T-cell depletion facilitates reduced immunosuppression following organ transplantation and has been suggested to be pro-tolerant. However, the characteristics of post-depletional T cells have not been evaluated as they relate to tolerance induction. We therefore studied patients undergoing profound T-cell depletion with alemtuzumab or rabbit anti-thymocyte globulin following renal transplantation, evaluating the phenotype and functional characteristics of their residual cells. Naive T cells and T cells with potential regulatory function (CD4+CD25+) were not prevalent following aggressive depletion. Rather, post-depletion T cells were of a single phenotype (CD3+CD4+CD45RA-CD62L-CCR7-) consistent with depletion-resistant effector memory T cells that expanded in the first month and were uniquely prevalent at the time of rejection. These cells were resistant to steroids, deoxyspergualin or sirolimus in vitro, but were calcineurin-inhibitor sensitive. These data demonstrate that therapeutic depletion begets a limited population of functional memory-like T cells that are easily suppressed with certain immunosuppressants, but cannot be considered uniquely pro-tolerant.
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Memoria Inmunológica/efectos de los fármacos , Inmunosupresores/farmacología , Subgrupos de Linfocitos T/efectos de los fármacos , Alemtuzumab , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales Humanizados , Anticuerpos Antineoplásicos/inmunología , Anticuerpos Antineoplásicos/farmacología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Inhibidores de la Calcineurina , Humanos , Memoria Inmunológica/inmunología , Trasplante de Riñón/inmunología , Subgrupos de Linfocitos T/inmunologíaRESUMEN
Renal allograft acute cellular rejection (ACR) is a T-cell mediated disease that is diagnosed histologically. However, many normally functioning allografts have T-cell infiltrates and histological ACR, and many nonimmune processes cause allograft dysfunction. Thus, neither histological nor functional criteria are sufficient to establish a significant rejection, and the fundamental features of clinical rejection remain undefined. To differentiate allograft lymphocyte infiltration from clinically significant ACR, we compared renal biopsies from patients with ACR to patients with: sub-clinical rejection (SCR, stable function with histological rejection); no rejection; and nontransplanted kidneys. Biopsies were compared histologically and transcriptionally by RT-PCR for 72 relevant immune function genes. Neither the degree nor the composition of the infiltrate defined ACR. However, transcripts up-regulated during effector T(H)1 T-cell activation, most significantly the transcription factor T-bet, the effector receptor Fas ligand and the costimulation molecule CD152 clearly (p = 0.001) distinguished the patient categories. Transcripts from other genes were equivalently elevated in SCR and ACR, indicating their association with infiltration, not dysfunction. Clinically significant ACR is not defined solely by the magnitude nor composition of the infiltrate, but rather by the transcriptional activity of the infiltrating cells. Quantitative analysis of selected gene transcripts may enhance the clinical assessment of allografts.
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Rechazo de Injerto/diagnóstico , Trasplante de Riñón , ARN Mensajero , Transcripción Genética , Adulto , Biopsia , Femenino , Perfilación de la Expresión Génica , Rechazo de Injerto/fisiopatología , Humanos , Riñón/metabolismo , Riñón/patología , MasculinoRESUMEN
BACKGROUND: Organs procured from deceased donors emanate from individuals with diverse genetic backgrounds. Donor organs, therefore, may vary in their response to injury and immune stimuli in a genetically determined manner. We assessed polymorphisms from 244 renal allograft donors to better understand the impact of donor polymorphisms on selected transplant outcomes. METHODS: Donor genomic DNA restriction fragment length polymorphisms were assayed for evidence of common cytokine [interleukin (IL)-2, IL-6, IL-10, tumor necrosis factor (TNF)-alpha, TGF-beta, interferon (IFN)-gamma] and chemokine (CCR2, CCR5) polymorphisms. Associations between donor polymorphisms and graft events were determined using chi-square, linear regression, and Kaplan-Meier analyses. RESULTS: Several genotypic polymorphisms demonstrated a modest association with acute rejection, including the transforming growth factor (TGF)-beta T/C codon 10 (P= 0.027) and the CCR5 G/A 59029 (P= 0.039) genes by chi-square analysis. Notably, the presence of the T allele in the IFN-gamma gene (+874) demonstrated a highly significant association with biopsy-proven chronic allograft nephropathy (P < 0.008). This association remained highly significant in a multiple linear regression model that incorporated biopsy-proven acute rejection as a covariate. CONCLUSION: These data suggest that many of the donor polymorphisms studied in this analysis may influence a recipient's immune response to a renal allograft. However, their greatest impact may be demonstrated in long-term outcomes.
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Rechazo de Injerto/genética , Enfermedades Renales/genética , Trasplante de Riñón , Polimorfismo Genético , Donantes de Tejidos , Enfermedad Aguda , Adulto , Enfermedad Crónica , Femenino , Heterogeneidad Genética , Genómica , Supervivencia de Injerto/genética , Humanos , Enfermedades Renales/cirugía , Modelos Lineales , Masculino , Persona de Mediana Edad , Trasplante HomólogoRESUMEN
BACKGROUND: Insulinomas are beta-cell tumours characterised by uncontrolled insulin secretion even in the presence of hypoglycaemia. However, the mechanisms allowing such excessive insulin secretion are not known. Insulin secretion can occur only when the beta-cell insulin stores have been replenished by insulin biosynthesis, which is mainly controlled by translation. Such specific translational regulation often involves the 5' untranslated region. We have identified an insulin splice variant in isolated human pancreatic islets of non-diabetic donors that retains 26 bp of intron 1 and thereby changes the 5' untranslated region, but leaves the coding region unchanged. This splice variant has increased translation efficiency in vitro and in vivo compared with native insulin mRNA. However, splice variant expression is less than 1% of native insulin mRNA in normal islets. METHODS: To test whether this splice variant is involved in insulin production by human insulinomas, we extracted RNA from nine laser-captured surgical insulinoma samples and from isolated islets of nine donors who did not have diabetes. We then determined the ratio of splice variant to native insulin mRNA by quantitative real-time RT-PCR. FINDINGS: The mean ratio of the splice variant to native insulin mRNA was increased more than 50-fold in insulinomas compared with normal islets, and this difference was present in all nine human insulinomas. Overexpression of the splice variant therefore seems to be a general characteristic of insulinomas and is estimated to contribute about 90% to insulin synthesis by these tumours. INTERPRETATION: Overexpression of the insulin splice variant with increased translation efficiency in insulinomas might explain how these tumours maintain high levels of insulin synthesis and secretion leading to hyperinsulinaemia-the hallmark of this disease.
Asunto(s)
Empalme Alternativo , Insulina/genética , Insulinoma/genética , Neoplasias Pancreáticas/genética , Animales , Línea Celular Tumoral , Femenino , Variación Genética , Humanos , Insulina/biosíntesis , Insulinoma/metabolismo , Islotes Pancreáticos/citología , Islotes Pancreáticos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Neoplasias Pancreáticas/metabolismo , ARN Mensajero/genéticaRESUMEN
Resistin, a recently described adipocyte factor, is regulated by peroxisome proliferator-activated receptor gamma (PPARgamma) agonists. While resistin has been proposed to mediate insulin resistance in rodents, little is known about human resistin and its expression in pancreatic islets has not been tested. The goal of the present study was therefore to analyze whether resistin, like PPARgamma, is expressed in islets. Human islets from seven donors were analyzed by quantitative RT-PCR revealing resistin expression in all samples. Immunohistochemistry using a resistin-specific antibody on human pancreatic sections localized resistin protein to the islets. Mouse resistin was also detected in the Min6 beta cell line. Interestingly, we found a 4-fold increase in islet resistin expression in insulin resistant A-ZIP transgenic compared to wild-type mice. Our results demonstrate that resistin is expressed in islets and up-regulated in insulin resistance and thereby shed new light on the role of resistin in mice and humans.