Project description:While it is well known that cell-free RNA (cfRNA) can be isolated from urine, the diagnostic potential of this urine cfRNA, especially in comparison to plasma cfRNA, remains underexplored. Here, we directly compared the utility of urine cfRNA and plasma cfRNA for the monitoring of systemic and urinary tract related complications. We analyzed 272 matched plasma and urine cfRNA isolates obtained from three cohorts of patients: Hematopoietic Stem Cell Transplant (HSCT) recipients, patients with acute kidney injury (AKI), and healthy volunteers. The data highlight the unique cellular origins and properties of urinary and plasma RNA. Most importantly, we find that although plasma cfRNA is a superior analyte for monitoring immune and systemic complications, urinary cfRNA is more sensitive to complications of the urinary tract, including cell-type specific injury in the kidney. These findings highlight the potential of urine cfRNA as a novel analyte in diagnostic medicine.
Project description:A total of 45 urine samples from 5 prostate cancer (PC) patients, 10 renal transplant patients with proven acute rejection (AR), 10 renal transplant patients with stable graft (STA), 10 non-specific proteinuria patients (NS), and 10 healthy individuals (HI), were utilized for global urine proteome profiling using 2D-LC-MS/MS. Peptides were digested with trypsin then analyzed by LC-MS/MS. Data was searched with MS-GF+ using PNNL's DMS Processing pipeline.
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:In transplantation, there is a critical need for non-invasive biomarker platforms for monitoring immunologic rejection. We hypothesized that transplanted tissues release donor specific exosomes into recipient circulation/ bodily fluids, and that the quantitation and profiling of their intra-exosomal cargoes would constitute a novel biomarker platform for monitoring rejection. We tested this hypothesis in a human into mouse xenogeneic islet transplant model, and validated the concept in clinical settings of islet and renal transplantation. In the xenogeneic model, islet transplant exosomes in recipient blood were quantified over long-term follow-up using anti-human leukocyte antigen (HLA) antibody that is only expressed on human islets (p=1.6x10-14). Transplant islet exosomes were purified using anti-HLA antibody conjugated beads and their cargoes contained bona fide islet endocrine hormone markers insulin, glucagon, and somatostatin. Rejection led to significant decrease in transplant islet exosome signal (p=4x10-15), along with distinct changes in its microRNA and proteomic profiles prior to appearance of hyperglycemia. In the clinical settings of islet (n=5) and renal (n=5) transplantation, donor exosomes with respective tissue specificity for islet β cells and renal epithelial cells were reliably characterized in recipient plasma over follow-up (up to 5 years; p=0.0001). Collectively, these findings demonstrate the biomarker potential of transplant exosome characterization for providing a non-invasive window into the conditional state of the transplant tissue.
Project description:In transplantation, there is a critical need for non-invasive biomarker platforms for monitoring immunologic rejection. We hypothesized that transplanted tissues release donor specific exosomes into recipient circulation/ bodily fluids, and that the quantitation and profiling of their intra-exosomal cargoes would constitute a novel biomarker platform for monitoring rejection. We tested this hypothesis in a human into mouse xenogeneic islet transplant model, and validated the concept in clinical settings of islet and renal transplantation. In the xenogeneic model, islet transplant exosomes in recipient blood were quantified over long-term follow-up using anti-human leukocyte antigen (HLA) antibody that is only expressed on human islets (p=1.6x10-14). Transplant islet exosomes were purified using anti-HLA antibody conjugated beads and their cargoes contained bona fide islet endocrine hormone markers insulin, glucagon, and somatostatin. Rejection led to significant decrease in transplant islet exosome signal (p=4x10-15), along with distinct changes in its microRNA and proteomic profiles prior to appearance of hyperglycemia. In the clinical settings of islet (n=5) and renal (n=5) transplantation, donor exosomes with respective tissue specificity for islet β cells and renal epithelial cells were reliably characterized in recipient plasma over follow-up (up to 5 years; p=0.0001). Collectively, these findings demonstrate the biomarker potential of transplant exosome characterization for providing a non-invasive window into the conditional state of the transplant tissue.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Kynureninase is a member of a large family of catalytically diverse but structurally homologous pyridoxal 5'-phosphate (PLP) dependent enzymes known as the aspartate aminotransferase superfamily or alpha-family. The Homo sapiens and other eukaryotic constitutive kynureninases preferentially catalyze the hydrolytic cleavage of 3-hydroxy-l-kynurenine to produce 3-hydroxyanthranilate and l-alanine, while l-kynurenine is the substrate of many prokaryotic inducible kynureninases. The human enzyme was cloned with an N-terminal hexahistidine tag, expressed, and purified from a bacterial expression system using Ni metal ion affinity chromatography. Kinetic characterization of the recombinant enzyme reveals classic Michaelis-Menten behavior, with a Km of 28.3 +/- 1.9 microM and a specific activity of 1.75 micromol min-1 mg-1 for 3-hydroxy-dl-kynurenine. Crystals of recombinant kynureninase that diffracted to 2.0 A were obtained, and the atomic structure of the PLP-bound holoenzyme was determined by molecular replacement using the Pseudomonas fluorescens kynureninase structure (PDB entry 1qz9) as the phasing model. A structural superposition with the P. fluorescens kynureninase revealed that these two structures resemble the "open" and "closed" conformations of aspartate aminotransferase. The comparison illustrates the dynamic nature of these proteins' small domains and reveals a role for Arg-434 similar to its role in other AAT alpha-family members. Docking of 3-hydroxy-l-kynurenine into the human kynureninase active site suggests that Asn-333 and His-102 are involved in substrate binding and molecular discrimination between inducible and constitutive kynureninase substrates.
Project description:Introduction: Renal ischemia-reperfusion (IR) causes acute kidney injury (AKI) with high mortality and morbidity. The objective of this study was to ameliorate kidney IR injury and identify novel biomarkers for kidney injury and repair. Methods: Left renal ischemia was induced in rats by clamping renal artery for 45 minutes, followed by reperfusion and right nephrectomy. Thirty minutes prior to ischemia, rats (n=8/group) received Valproic Acid (150 mg/kg; VPA), Dexamethasone (3 mg/kg; Dex) or Vehicle (Saline) intraperitoneally. Animals were sacrificed at 3h, 24h or 120h post- IR and blood, urine and kidney were collected. Results: Serum creatinine (mg/dL) at 24 h IR in VPA (2.7±1.8) and Dex (2.3±1.2) was reduced (P<0.05) compared to Vehicle (3.8±0.5). At 3h post-IR, urine albumin (mg/ml) was higher in Vehicle (1.47±0.10), VPA (0.84±0.62) and Dex (1.04±0.73) compared to uninjured/untreated control (0.14±0.26) group. At 24h post-IR urine Lipocalin-2 (µg/ml) was significantly higher (P<0.05) in VPA, Dex and Vehicle groups (9.61-11.36) compared to uninjured/untreated control (0.67±o.29); also, Kidney Injury Molecule-1 (KIM-1; ng/ml) was significantly higher in VPA, Dex and Vehicle groups (13.7-18.7) compared uninjured/untreated control (1.7±1.9). KIM-1 levels were significantly (P<0.05) higher in all groups compared to uninjured/untreated control levels. Histopathology at 3h post IR demonstrated (P<0.05) reduction in ischemic injury in the renal cortex in VPA (Grade 1.6± 1.5) compared to Vehicle (Grade 2.9±1.1) group. Inflammatory cytokines IL1β and IL6 were down-regulated in VPA and Dex groups. BCL2 was higher in VPA group. DNA microarray analysis demonstrated reduced stress response and injury, and improved recovery related gene expression in the kidneys of VPA treated animals. Conclusions: VPA administration reduced kidney IR injury and improved regeneration. KIM-1 and Lipocalin-2 appear to be promising early urine biomarkers of acute ischemic kidney injury. We had three experimental groups. Group A, VPA treatment; Group B, Dexamethasone treatment; and Group C, No treatment (vehicle saline control). Treatments were administered prior to the induction of left renal ischemia. Animals underwent 45 minutes of left renal ischemia, followed by reperfusion, and right nephrectomy as described above. Following reperfusion, animals were sacrificed at 3, 24 or 120 hours (n=8/group). In the 3 hour group, rats were maintained under anesthesia after surgery until sacrifice. In the 24 and 120 hour groups, the rats were recovered and returned to the cages for normal housing. Analgesic buprenorphine (0.05mg/kg) was administered every 12 h for three days post-operatively. After animal sacrifice, urine, blood, and kidney were collected for kidney functional biomarker assays, histology and / or molecular analyses. Urine was obtained via cystocentesis and blood was obtained via the left renal vein. Tissue and urine samples collected from normal (naïve) animals (n=5) were used for baseline measurements. A subset of 46 animals (n = 4-5 per group) were selected for microarray analysis.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.