MOLECULAR CHARACTERIZATION OF LIVER ALLOGRAFTS FROM OPERATIONALLY TOLERANT TRANSPLANT RECIPIENTS
Ontology highlight
ABSTRACT:
SUBMITTER:
PROVIDER: S-DIXA-D-1080 | biostudies-other |
REPOSITORIES: biostudies-other
Similar Datasets
Project description:This SuperSeries is composed of the SubSeries listed below.
2012-01-09 | GSE26627 | GEO
Project description:This SuperSeries is composed of the following subset Series: GSE26622: MOLECULAR CHARACTERIZATION OF LIVER ALLOGRAFTS FROM OPERATIONALLY TOLERANT TRANSPLANT RECIPIENTS (Affymetrix) GSE26625: MOLECULAR CHARACTERIZATION OF LIVER ALLOGRAFTS FROM OPERATIONALLY TOLERANT TRANSPLANT RECIPIENTS (Illumina) Refer to individual Series
2012-01-09 | E-GEOD-26627 | biostudies-arrayexpress
Project description:In clinical organ transplantation complete cessation of immunosuppressive therapy can be successfully accomplished in selected recipients providing a proof-of-principle that allograft tolerance is attainable in humans. The intra-graft molecular pathways associated with human allograft tolerance, however, have not been comprehensively studied before. In this study we analyzed sequential liver tissue samples collected from liver recipients enrolled in a prospective multicenter immunosuppressive withdrawal clinical trial. Tolerant and non-tolerant recipients differed in the intra-graft expression of genes involved in the regulation of iron homeostasis.These results point to a critical role of iron homeostasis in the regulation of intra-graft alloimmune responses in humans and provide a set of novel biomarkers to conduct drug-weaning trials in liver transplantation.
2012-01-09 | GSE26625 | GEO
Project description:In clinical organ transplantation complete cessation of immunosuppressive therapy can be successfully accomplished in selected recipients providing a proof-of-principle that allograft tolerance is attainable in humans. The intra-graft molecular pathways associated with human allograft tolerance, however, have not been comprehensively studied before. In this study we analyzed sequential liver tissue samples collected from liver recipients enrolled in a prospective multicenter immunosuppressive withdrawal clinical trial. Tolerant and non-tolerant recipients differed in the intra-graft expression of genes involved in the regulation of iron homeostasis.These results point to a critical role of iron homeostasis in the regulation of intra-graft alloimmune responses in humans and provide a set of novel biomarkers to conduct drug-weaning trials in liver transplantation.
2012-01-09 | GSE26622 | GEO
Project description:In clinical organ transplantation complete cessation of immunosuppressive therapy can be successfully accomplished in selected recipients providing a proof-of-principle that allograft tolerance is attainable in humans. The intra-graft molecular pathways associated with human allograft tolerance, however, have not been comprehensively studied before. In this study we analyzed sequential liver tissue samples collected from liver recipients enrolled in a prospective multicenter immunosuppressive withdrawal clinical trial. Tolerant and non-tolerant recipients differed in the intra-graft expression of genes involved in the regulation of iron homeostasis.These results point to a critical role of iron homeostasis in the regulation of intra-graft alloimmune responses in humans and provide a set of novel biomarkers to conduct drug-weaning trials in liver transplantation. The complete database comprised the expression measurements of 54,675 genes for liver inmunotolerance groups: 9 Tolerant (TOL) 10 Non Tolerant (Non TOL).A subset of 5 tolerant samples (TOL POST) were taken 1 year after inmunosuppresive therapy.
2012-01-09 | E-GEOD-26622 | biostudies-arrayexpress
Project description:In clinical organ transplantation complete cessation of immunosuppressive therapy can be successfully accomplished in selected recipients providing a proof-of-principle that allograft tolerance is attainable in humans. The intra-graft molecular pathways associated with human allograft tolerance, however, have not been comprehensively studied before. In this study we analyzed sequential liver tissue samples collected from liver recipients enrolled in a prospective multicenter immunosuppressive withdrawal clinical trial. Tolerant and non-tolerant recipients differed in the intra-graft expression of genes involved in the regulation of iron homeostasis.These results point to a critical role of iron homeostasis in the regulation of intra-graft alloimmune responses in humans and provide a set of novel biomarkers to conduct drug-weaning trials in liver transplantation. The complete database comprised the expression measurements of 48766 probes in liver biopsies. The liver biopsy specimens available for the study were obtained: a) before immunosuppressive drugs were discontinued from tolerant (TOL, n=24) and non-tolerant (Non-TOL, n=29) recipients; b) at the time of rejection from non-tolerant recipients (Non TOL REJ, n=18); In addition, liver tissue samples were also collected from the following control patient groups: a) liver transplant recipients with chronic hepatitis due to recurrent hepatitis C virus infection (HEPC, n=12); b) liver transplant recipients with typical acute cellular rejection taking place during the immediate post-transplant period (REJ, n=9); c) liver transplant recipients under maintenance immunosuppression with normal liver function and normal liver histology 1 year after transplantation (CONT-Tx, n=8); and d) non-transplanted patients undergoing surgery for colorectal liver metastases (CONT, n=10).
2012-01-09 | E-GEOD-26625 | biostudies-arrayexpress
Project description:The objective of this study was to analyse the mechanisms of resistance to carbapenems and other extended-spectrum-β-lactams and to determine the genetic relatedness of multidrug-resistant Enterobacterales (MDR-E) causing colonization or infection in solid-organ transplantation (SOT) recipients. Prospective cohort study in kidney (n = 142), liver (n = 98) or kidney/pancreas (n = 7) transplant recipients between 2014 and 2018 in seven Spanish hospitals. We included 531 MDR-E isolates from rectal swabs obtained before transplantation and weekly for 4-6 weeks after the procedure and 10 MDR-E from clinical samples related to an infection. Overall, 46.2% Escherichia coli, 35.3% Klebsiella pneumoniae, 6.5% Enterobacter cloacae, 6.3% Citrobacter freundii and 5.7% other species were isolated. The number of patients with MDR-E colonization post-transplantation (176; 71.3%) was 2.5-fold the number of patients colonized pre-transplantation (71; 28.7%). Extended-spectrum β-lactamases (ESBLs) and carbapenemases were detected in 78.0% and 21.1% of MDR-E isolates respectively. In nine of the 247 (3.6%) transplant patients, the microorganism causing an infection was the same strain previously cultured from surveillance rectal swabs. In our study we have observed a low rate of MDR-E infection in colonized patients 4-6 weeks post-transplantation. E. coli producing blaCTX-M-G1 and K. pneumoniae harbouring blaOXA-48 alone or with blaCTX-M-G1 were the most prevalent MDR-E colonization strains in SOT recipients.
| S-EPMC8178318 | biostudies-literature
Project description:Liver biopsy samples were obtained as part of the LITMUS trial (ClinicalTrials.gov NCT02541916). All samples were obtained from liver transplant recipients prior to immunosuppression withdrawal. Percutaneous liver biopsies were performed under local anaesthesia using an 18-gauge Jamshidi needle. A 0.5cm portion of the biopsy to be used for gene expression was stored in RNAlater (Qiagen) for 24 hours at 4 °C and then transferred to -80 °C. Specimens were thawed and transferred to a clean, RNase free microcentrifuge tube. Tissue samples were incubated in 600 ul of lysis buffer (Ambion) with 6 ul of 2-mercaptoethanol for 10 minutes. Tissue samples were then homogenized using a nuclease-free disposable pellet pestle (Kimble Kontes) and processed using the PureLink RNA Mini Kit (Ambion). RNA quality was evaluated using an Bioanalyzer 2100 (Agilent) and samples with RIN > 7 were submitted for sequencing and analysis at The Center for Applied Genomics (Toronto, Canada).
2022-02-09 | GSE175397 | GEO
Project description:LITMUS was a single-centre, Phase 2a study designed to investigate whether the gene biomarker FGL2/IFNG previously reported for the identification of tolerance in murine models could identify operationally tolerant liver transplant recipients. Multiplex RT-PCR was used to amplify eight immunoregulatory genes in peripheral blood mononuclear cells (PBMC) from 69 adult liver transplant recipients. Patients with PBMC FGL2/IFNG ≥ 1 and a normal liver biopsy underwent immunosuppression (IS) withdrawal. The primary end point was the development of operational tolerance. Secondary end points included correlation of tolerance with allograft gene expression and immune cell markers. Twenty-eight of 69 patients (38%) were positive for the PBMC tolerance biomarker and 23 proceeded to IS withdrawal. Nine of the 23 patients had abnormal baseline liver biopsies and were excluded. Of the 14 patients with normal biopsies, eight (57%) have achieved operational tolerance and are off IS (range 12-57 months). Additional studies revealed that all of the tolerant patients and only one non-tolerant patient had a liver gene ratio of FOXP3/IFNG ≥ 1 prior to IS withdrawal. Increased CD4+ T regulatory T cells were detected both in PBMC and livers of tolerant patients following IS withdrawal. Higher expression of SELE (gene for E-selectin) and lower expression of genes associated with inflammatory responses (GZMB, CIITA, UBD, LSP1, and CXCL9) were observed in the pre-withdrawal liver biopsies of tolerant patients by RNA sequencing. These results suggest that measurement of PBMC FGL2/IFNG may enrich for the identification of operationally tolerant liver transplant patients, especially when combined with intragraft measurement of FOXP3/IFNG. Clinical Trial Registration: ClinicalTrials.gov (LITMUS: NCT02541916).
| S-EPMC8802178 | biostudies-literature
Project description:Nonalcoholic fatty liver disease (NAFLD) and its progressive form nonalcoholic steatohepatitis (NASH) are a growing problem globally and recur even after liver transplant (LT). We aim to characterize the gut dysbiosis in patients who developed recurrent NAFLD compared with patients without recurrence following LT.MethodsTwenty-one patients who received LT for NASH and had a protocol liver biopsy performed beyond 1-y post-LT were included prospectively (January 2018-December 2018). Genomic DNA extraction, next-generation sequencing, and quantitative PCR analysis were performed on stool samples collected within 1.1 ± 1.6 y from time of liver biopsy.ResultsRecurrent NAFLD was noted in 15 of the 21 included patients. Stool microbiome analysis at the genus level showed significant loss of Akkermansia and increasing Fusobacterium associated with NAFLD recurrence. Quantitative PCR analysis revealed significantly decreased relative abundance of Firmicutes in patients with NAFLD activity scores (NASs) ≥5 as compared with patients with lower NAS scores, whereas Bacteroidetes were significantly increased with higher NAS (P < 0.05). Firmicutes (P = 0.007) and Bifidobacterium group (P = 0.037) were inversely correlated, whereas Bacteroidetes (P = 0.001) showed a positive correlation with higher hepatic steatosis content. The Firmicutes/Bacteroidetes ratios were higher in patients without NAFLD or NASH as compared with patients diagnosed with NAFLD or NASH at the time of sample collection.ConclusionsAkkermansia, Firmicutes, and Bifidobacterium may play protective roles in the development of recurrent NAFLD in LT recipients, whereas Fusobacteria and Bacteroidetes may play pathogenic roles. These findings highlight the potential role of the "gut-liver" axis in the pathogenesis of NAFLD recurrence after LT.
| S-EPMC7665248 | biostudies-literature