This SuperSeries is composed of the SubSeries listed below.
Recurrent variations in DNA methylation in human pluripotent stem cells and their differentiated derivatives.
Sex, Specimen part, Disease, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Development and clinical validity of a novel blood-based molecular biomarker for subclinical acute rejection following kidney transplant.
Specimen part
View SamplesSub-clinical acute rejection (subAR) in kidney transplant recipients (KTR) leads to chronic rejection and graft loss. Non-invasive biomarkers are needed to detect subAR. 307 KTR were enrolled into a multi-center observational study. Precise clinical phenotypes (CP) were used to define subAR. Differential gene expression (DGE) data from peripheral blood samples paired with surveillance biopsies were used to train a Random Forests (RF) model to develop a gene expression profile (GEP) for subAR. A separate cohort of paired samples was used to validate the GEP. Clinical endpoints and gene pathway mapping were used to assess clinical validity and biologic relevance. DGE data from 530 samples (130 subAR) collected from 250 KTR yielded a RF model: AUC 0.85; 0.84 after internal validation with bootstrap resampling. We selected a predicted probability threshold favoring specificity and NPV (87% and 88%) over sensitivity and PPV (64% and 61%, respectively). We tested the locked model/threshold on a separate cohort of 138 KTR undergoing surveillance biopsies at our institution (rejection 42; no rejection 96): NPV 78%; PPV 51%; AUC 0.66. Both the CP and GEP of subAR within the first 12 months following transplantation were independently associated with worse graft outcomes at 24 months, including de novo donor-specific antibody (DSA). Serial GEP tracked with response to treatment of subAR. DGE data from both cohorts mapped to gene pathways indicative of allograft rejection.
Development and clinical validity of a novel blood-based molecular biomarker for subclinical acute rejection following kidney transplant.
Specimen part
View SamplesEarly diagnosis of transthyretin (TTR) amyloid diseases remains challenging because of variable disease penetrance. Currently, patients must have an amyloid positive tissue biopsy to be eligible for disease modifying therapies. Early diagnosis is often difficult because the patient exhibits apparent symptoms of polyneuropathy or cardiomyopathy, but has a negative amyloid biopsy. Thus, there is a pressing need for more objective, quantitative diagnostics and biomarkers of TTR-aggregation-associated polyneuropathy and cardiomyopathy. This is especially true in the context of clinical trials demonstrating significant disease modifying effects, e.g. when the TTR tetramer stabilizer tafamidis was administered to familial amyloid polyneuropathy (FAP) patients early in the disease course. When asked if the findings of the tafamidis registration trial were sufficiently robust to provide substantial evidence of efficacy for a surrogate endpoint that is reasonably likely to predict a clinical benefit the advisory committee said yes, but the FDA rejected the tetramer stabilization surrogate biomarker required for orphan tafamidis approvalhence, acceptable biomarkers are badly needed. Herein, we explored whether peripheral blood cell mRNA expression profiles could differentiate symptomatic from asymptomatic V30M FAP patients, and if such a profile would normalize upon tafamidis treatment. We demonstrate that blood cell gene expression patterns reveal sex-independent as well as male and female specific inflammatory signatures in symptomatic FAP patients, but not in asymptomatic carriers, that normalize in FAP patients 6 months after tafamidis treatment. Thus these signatures have potential both as an early diagnostic and as a surrogate biomarker for measuring response to treatment in FAP patients.
Peripheral Blood Cell Gene Expression Diagnostic for Identifying Symptomatic Transthyretin Amyloidosis Patients: Male and Female Specific Signatures.
Age, Specimen part
View SamplesRationale: Interstitial fibrosis and tubular atrophy (IFTA) is found in ~25% of 1-year biopsies post-transplant(1, 2). It correlates with decreased graft survival when histological evidence of inflammation is present.(3-5) Identifying the etiology of IFTA is important because longterm graft survival has not changed as expected given improved therapies and a dramatically reduced incidence of acute rejection.(6-8) Methods: Gene expression profiles of 234 samples were obtained with matching clinical and outcome data (7 transplant centers). 81 IFTA samples were divided into subphenotypes by the degree of inflammation on histology: IFTA with acute rejection (AR), IFTA with inflammation and IFTA without inflammation. Samples with AR (n=54) and normally functioning transplants (TX; n=99) were used in comparisons. Conclusions: Gene expression profiling of all IFTA phenotypes were strongly enriched for cAR gene dysregulation pathways, including IFTA samples without histological evidence of inflammation. Thus, by molecular profiling we demonstrate that most IFTA samples have ongoing immune-mediated injury or chronic rejection that is more sensitively detected by gene expression profiling. We also found that the relative expression of AR-affiliated genes correlated with future graft loss in IFTA samples without inflammation. We conclude that undetected and/or undertreated immune rejection is leading to IFTA and graft failure.
Gene Expression in Biopsies of Acute Rejection and Interstitial Fibrosis/Tubular Atrophy Reveals Highly Shared Mechanisms That Correlate With Worse Long-Term Outcomes.
Specimen part, Disease, Disease stage
View SamplesHuman pluripotent stem cells (hPSCs) are potential sources of cells for modeling disease and development, drug discovery, and regenerative medicine. However, it is important to identify factors that may impact the utility of hPSCs for these applications. In an unbiased analysis of 205 hPSC and 130 somatic samples, we identified hPSC-specific epigenetic and transcriptional aberrations in genes subject to X chromosome inactivation (XCI) and genomic imprinting, which were not corrected during directed differentiation. We also found that specific tissue types were distinguished by unique patterns of DNA hypomethylation, which were recapitulated by DNA demethylation during in vitro directed differentiation. Our results suggest that verification of baseline epigenetic status is critical for hPSC-based disease models in which the observed phenotype depends on proper XCI or imprinting, and that tissue-specific DNA methylation patterns can be accurately modeled during directed differentiation of hPSCs, even in the presence of variations in XCI or imprinting.
Recurrent variations in DNA methylation in human pluripotent stem cells and their differentiated derivatives.
Sex, Specimen part, Cell line, Subject
View SamplesIn this study we employed transcriptome mRNA profiling of whole blood and purified CD4, CD8 T cells, B cells and monocytes in tandem with high-throughput flow cytometry in 10 kidney transplant patients sampled serially pre-transplant, 1, 2, 4, 8 and 12 weeks. We then mechanistically deconvoluted the early post-transplant immune response. The flow cytometry data confirms depletion of specific cell subsets in response to ATG induction and immunosuppression with sustained decreases in CD4 as well as CD8 cell subsets. A series of T cell activation markers were expressed from Pre-Tx to 12 weeks indicating the evolution of immunity including expansion of CD45RO+CD62L- effector memory cells. Serial whole blood transcript monitoring demonstrated over 2000 differentially expressed genes, with over 80 percent down-regulated Post-Tx. However, cell subset analysis revealed a unique spectrum of subset-specific gene expression with time-dependent changes, with contrasting significant Post-Tx gene upregulation. Our results provide a unique view of the complex evolution of immune/inflammatory molecular networks marking the early post transplant immune response. A critical finding is that analysis of the constituent blood cell subsets provides an entirely new level of detail revealing the nature of this process, effectively deconvoluting the changes that are otherwise lost in the noise of cellular complexity of whole blood.
Deconvoluting post-transplant immunity: cell subset-specific mapping reveals pathways for activation and expansion of memory T, monocytes and B cells.
Time
View SamplesFibromyalgia (FM) is a common pain disorder characterized by dysregulation in the processing of pain. Although FM has similarities with other rheumatologic pain disorders, the search for objective markers has not been successful. In the current study we analyzed gene expression in the whole blood of 70 fibromyalgia patients and 70 healthy matched controls. Global molecular profiling revealed an upregulation of several inflammatory molecules in FM patients and downregulation of specific pathways related to hypersensitivity and allergy. There was a differential expression of genes in known pathways for pain processing, such as glutamine/glutamate signaling and axonal development. We also identified a panel of candidate gene expression-based classifiers that could establish an objective blood-based molecular diagnostic to objectively identify FM patients and guide design and testing of new therapies. Ten classifier probesets (CPA3, C11orf83, LOC100131943, RGS17, PARD3B, ANKRD20A9P, TTLL7, C8orf12, KAT2B and RIOK3) provided a diagnostic sensitivity of 95% and a specificity of 96%. Molecular scores developed from these classifiers were able to clearly distinguish FM patients from healthy controls. An understanding of molecular dysregulation in fibromyalgia is in its infancy; however the results described herein indicate blood global gene expression profiling provides many testable hypotheses that deserve further exploration.
Genome-wide expression profiling in the peripheral blood of patients with fibromyalgia.
Specimen part, Disease
View SamplesSub-clinical acute rejection (subAR) in kidney transplant recipients (KTR) leads to chronic rejection and graft loss. Non-invasive biomarkers are needed to detect subAR. 307 KTR were enrolled into a multi-center observational study. Precise clinical phenotypes (CP) were used to define subAR. Differential gene expression (DGE) data from peripheral blood samples paired with surveillance biopsies were used to train a Random Forests (RF) model to develop a gene expression profile (GEP) for subAR. A separate cohort of paired samples was used to validate the GEP. Clinical endpoints and gene pathway mapping were used to assess clinical validity and biologic relevance. DGE data from 530 samples (130 subAR) collected from 250 KTR yielded a RF model: AUC 0.85; 0.84 after internal validation with bootstrap resampling. We selected a predicted probability threshold favoring specificity and NPV (87% and 88%) over sensitivity and PPV (64% and 61%, respectively). We tested the locked model/threshold on a separate cohort of 138 KTR undergoing surveillance biopsies at our institution (rejection 42; no rejection 96): NPV 78%; PPV 51%; AUC 0.66. Both the CP and GEP of subAR within the first 12 months following transplantation were independently associated with worse graft outcomes at 24 months, including de novo donor-specific antibody (DSA). Serial GEP tracked with response to treatment of subAR. DGE data from both cohorts mapped to gene pathways indicative of allograft rejection.
Development and clinical validity of a novel blood-based molecular biomarker for subclinical acute rejection following kidney transplant.
No sample metadata fields
View SamplesDespite the significant reduction in the overall burden of cardiovascular disease (CVD) over the past decade, CVD still accounts for a third of all deaths in the United States and worldwide each year. While efforts to identify and reduce risk factors for atherosclerotic heart disease (i.e. hypertension, dyslipidemia, diabetes mellitus, cigarette smoking, inactivity) remain the focus of primary prevention, the inability to accurately and temporally predict acute myocardial infarction (AMI) impairs our ability to further improve patient outcomes. Our diagnostic evaluation for the presence of coronary artery disease relies on functional testing, which detects flow-limiting coronary stenosis, but we have known for decades that most lesions underlying AMI are only of mild to moderate luminal narrowings, not obstructing coronary blood flow. Accordingly, there is a dire need of improved diagnostics for underlying arterial plaque dynamics, fissure and rupture. Here we describe the designation of a specific gene expression pattern acting as a molecular signature for acute myocardial infarction present in whole blood of patients that was determined using microarray analysis of enriched circulating endothelial cells (CEC).
A Whole Blood Molecular Signature for Acute Myocardial Infarction.
Specimen part, Disease
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