Characterization of Human Pegivirus Infection in Liver Transplantation Recipients
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ABSTRACT: Approximately 2% of heathy persons are infected with human pegivirus (HPgV). HPgV is transmitted via vertical, sexual, and blood-borne routes. Recently, the association of HPgV infection with the risk of lymphoma was reported. We examined the prevalence of chronic HPgV infection in liver transplantation (LT) recipients and hepatectomy patients and the influence of HPgV infection after LT on clinical and perioperative factors. We enrolled 313 LT recipients and 187 hepatectomy patients who received care at the Kyusyu University Hospital between May 1997 and September 2017. Total RNA was extracted from peripheral blood samples of patients/recipients collected postoperatively. HPgV RNA was measured using real-time polymerase chain reaction (RT-PCR). Of the 313 recipients and 187 patients enrolled in this study, 44 recipients (14.1%) and two patients (1.1%) had HPgV viremia. There was no significant association between HPgV infection and LT outcomes. Interestingly, one recipient was infected with HPgV during the peritransplant period, which was likely transmitted via blood transfusion as HPgV RNA was detected from the blood bag transfused to the recipient during LT. Additionally, HPgV infection induced the upregulation of interferon stimulated gene (ISG) expression in peripheral blood mononuclear cells (PBMCs). LT recipients had higher HPgV viremia compared to hepatectomy patients. Although HPgV infection was not associated with LT-related outcomes, it induced ISG expression in recipients.
Project description:We study the global gene expression profiles of BKV viremia and nephropathy patients using microarrays in order to better understand the immunologic response to polyomavirus BK (BKV). BKV has become increasingly prevalent since the introduction of more potent immunosuppressive agents. It has been shown that as many as 30% of renal transplant recipients develop asymptomatic viral shedding in the urine shortly after transplant, 10-20% have viremia, and as many as 1-10% can go on to develop overt nephropathy (BKVN) that might lead to graft loss. To date, the genomics of BKV viremia and BKVN have not been investigated thoroughly by microarray. Patients who were enrolled in the IRB-approved Immune Monitoring Study had blood PAXGene samples taken at post-transplant visits and had clinically indicated biopsy samples were used for analysis. A total of 17 biopsy samples were used for gene expression profiling microarrays, three with histopathologic diagnosis of BKVN, 3 patients with evidence of BK viral replication in peripheral blood, but normal biopsy and 11 patients with normal biopsies or mild IFTA, and stable graft function. Blood PAXGene samples from 40 patients were used for gene expression profiling by microarrays, 14 patients with stable graft function and without BK viremia, 19 patients' blood samples at the time of BKV viremia, and 7 patients blood samples taken 1-2 months prior to development of BK viremia.
Project description:Liver transplantation (LT) for Hepatocellular carcinoma (HCC) can be offered to patients beyond Milan criteria. However, there are currently no molecular markers that can be used on HCC explant histology to predict recurrence, which arises in up to 20% of LT recipients . The goal of our study was to identify proteins on HCC explant predictive of recurrence post-transplant, thereby guiding surveillance strategies and identifying patients beyond Milan criteria who would fare well following LT.
Project description:We study the global gene expression profiles of BKV viremia and nephropathy patients using microarrays in order to better understand the immunologic response to polyomavirus BK (BKV). BKV has become increasingly prevalent since the introduction of more potent immunosuppressive agents. It has been shown that as many as 30% of renal transplant recipients develop asymptomatic viral shedding in the urine shortly after transplant, 10-20% have viremia, and as many as 1-10% can go on to develop overt nephropathy (BKVN) that might lead to graft loss. To date, the genomics of BKV viremia and BKVN have not been investigated thoroughly by microarray.
Project description:Background: Although the clinical fingerprints of the BK virus (BKV) infection in kidney transplant recipients (KTRs) has been well documented, the systemic biological machinery involved in this complication is still poorly recognized. Proteomics analysis of urinary extracellular vesicles (EVs) can allow us to better address this knowledge gap. Methods: Twenty-nine adult KTRs with normal allograft function affected by BKV infection (15 with only viremia, 14 with viruria and viremia) and 15 controls (CTR) were enrolled and randomly divided in a training cohort (12 BKV and 6 CTR) used for the mass spectrometry analysis of the EVs protein content and a testing cohort(17 BKV and 9 CTR) used for the biological validation of the proteomic results by ELISA. Results: Mass spectrometry analysis revealed a large protein enrichment (more than 1500) in urinary EVs of BKV patients and controls. Pathway analysis by GSEA revealed that several biological gene ontologies (including immunity, complement activation, renal fibrosis, tubular diseases, epithelial to mesenchymal transition) were able to discriminate BKV versus CTR. Kinase was the only gene ontology annotation term negatively enriched in BKV (with SLK being the most down-regulated protein in BKV). Statistical analysis, then, identified a core panel of 70 proteins (including DNASE2, F12, AGT, CTSH, C4A, C7, FABP4 and BPNT1) able to discriminate the two study groups. Instead, although a set of proteins were able to differentiate patients with BKV viruria from those with both viremia-viruria, the urinary proteomic profile of these patients resulted quite similar between the two sub-groups. ELISA for SLK and ELISA for BPNT1 and DNASE2 validated proteomics results. Conclusions: Our study demonstrated that BK virus infection is able to significantly modify the urinary EVs proteomic profile of KTRs also in a very early stage of the disease (when patients still have normal allograft function and only BK viruria) suggesting, whether possible, to start an early preventive therapeutic approach to minimize the risk of the disease progression. Moreover, some 3 of our identified proteins could be employed in future as early urinary biomarkers and/or new therapeutic targets.
Project description:Selecting the right immunosuppressant to ensure rejection-free outcomes poses unique challenges in pediatric liver transplant (LT) recipients. A molecular predictor can comprehensively address these challenges. Although early acute cellular rejection (ACR) is mediated by cytotoxic T-cells, late rejection also includes antibody-mediated damage in addition to cell-mediated injury. Currently, there are no well-validated blood-based biomarkers for pediatric LT recipients either pre- or post- transplant. Here, we discover and validate separate pre- and post- transplant molecular signatures of LT outcome from whole blood transcriptomes. Using an integrative machine learning approach, we combine transcriptomic data with the high-quality reference human protein interactome network to identify differentially regulated functional sub-components of the network, or “network module signatures”, which drive ACR. Unlike gene signatures, our approach is inherently multivariate, more robust to replication and captures the structure of the underlying molecular network, encapsulating additive effects. We also identify, in a patient-specific manner, network module signatures that can be targeted by current anti-rejection drugs and other mechanisms that can be repurposed. Overall, our approach can enable personalized adjustment of drug regimens for the dominant targetable pathways in pre- and post- LT in children.
Project description:Background: Hepatitis E Virus (HEV) is a new causative agent of chronic hepatitis in solid organ transplant recipients in Europe. Factors associated with the occurrence and persistence of chronic HEV infection remain largely unknown but chronic evolution seems to be the consequence of hostM-bM-^@M-^Ys immunological factors rather than of viral factors. Method: In a prospective case-control study, we have determined in whole blood of chronically HEV-infected kidney-transplant recipients the host response using microarray technology. Results: Chronically HEV-infected kidney-transplant recipients exhibited a specific transcriptional program, in which interferon effectors were prominent. The intensity of expression of each signatureM-bM-^@M-^Ys gene was significantly lower in patients who were subsequently cleared of HEV than in patients who were not. Furthermore, in patients who were cleared of HEV, a higher expression of these genes was associated with a longer delay until HEV clearance. Conclusions: The specific transcriptional program determined in chronically HEV-infected kidney-transplant recipients suggests an activation of type I interferon response. Intensity of interferon-stimulated genes expression could be useful to forecast the outcome of infection. High expression of interferon-stimulated genes could signify a dysregulation in the interferon response that might favour the persistence of the HEV infection. TrialM-bM-^@M-^Ys registration number: NCT01090232; RegistryM-bM-^@M-^Ys URL: http://clinicaltrials.gov/ct2/show/study/NCT01090232?term=kidney+transplant+recipients&cntry1=EU%3AFR&rank=2 Total RNA was extracted from whole-blood sample or monocytes of kidney-transplant patients with or without chronic hepatitis E (CHE) infection. Control patients were matched up with CHE patients for age, sex, time since kidney transplant and immunosuppressive treatment.
Project description:Cutaneous leishmaniasis is a localized infection controlled by CD4+ T cells that produce IFN-g within lesions. Phagocytic cells recruited to lesions, such as monocytes, are then exposed to IFN-g which triggers their ability to kill the intracellular parasites. Consistent with this, a transcriptional analysis of lesions from patients identified the presence of a strong interferon stimulated gene (ISG) signature. To determine what systemic responses are occurring that might influence the disease, we performed RNA sequencing (RNA-seq) on the blood of L. braziliensis-infected patients, as well as healthy controls. Functional enrichment analysis identified a transcriptional ISG signature as the dominant response in the blood of patients. An increase in monocytes and macrophages in the blood, estimated from our RNA-seq dataset, was positively correlated with this ISG signature. Consistent with this result, patients had circulating IFN-g in their serum. A cytotoxicity signature, which is a dominant feature in the lesions, was also found in the blood and correlated with an increased abundance of cytolytic cells. Thus, two transcriptional signatures present in lesions were found systemically, although with a substantially reduced number of differentially expressed genes (DEGs). Finally, we found that the number of DEGs and ISGs in leishmaniasis was similar to tuberculosis – another localized infection – but significantly less than observed in malaria. In contrast, the cytolytic signature and increased cytolytic cell abundance was not found in tuberculosis or malaria. Our results indicate that systemic signatures can reflect what is occurring in leishmanial lesions. Furthermore, the presence of an ISG signature in blood monocytes and macrophages suggests that when these cells enter lesions they may already be primed to control the parasites.
Project description:Endomucin (EMCN) currently represents the only hematopoietic stem cell (HSC) marker expressed by both murine and human HSCs. Here, we report that EMCN+ long-term repopulating HSCs (LT-HSCs; CD150+CD48−LSK) have a higher long-term multi-lineage repopulating capacity compared to EMCN− LT-HSCs. Cell cycle analyses and transcriptional profiling demonstrated that EMCN+ LT-HSCs were more quiescent compared to EMCN− LT-HSCs. Emcn−/− and Emcn+/+ mice displayed comparable steady-state hematopoiesis, as well as frequencies, transcriptional programs, and long-term multi-lineage repopulating capacity of their LT-HSCs. Complementary functional analyses further revealed increased cell cycle entry upon treatment with 5-fluorouracil and reduced granulocyte colony-stimulating factor (GCSF) mobilization of Emcn−/− LT-HSCs, demonstrating that EMCN expression by LT-HSCs associates with quiescence in response to hematopoietic stress and is indispensable for effective LT-HSC mobilization. Transplantation of wild-type bone marrow cells into Emcn−/− or Emcn+/+ recipients demonstrated that EMCN is essential for endothelial cell-dependent maintenance/self-renewal of the LT-HSC pool and sustained blood cell production post-transplant.
Project description:Endomucin (EMCN) currently represents the only hematopoietic stem cell (HSC) marker expressed by both murine and human HSCs. Here, we report that EMCN+ long-term repopulating HSCs (LT-HSCs; CD150+CD48−LSK) have a higher long-term multi-lineage repopulating capacity compared to EMCN− LT-HSCs. Cell cycle analyses and transcriptional profiling demonstrated that EMCN+ LT-HSCs were more quiescent compared to EMCN− LT-HSCs. Emcn−/− and Emcn+/+ mice displayed comparable steady-state hematopoiesis, as well as frequencies, transcriptional programs, and long-term multi-lineage repopulating capacity of their LT-HSCs. Complementary functional analyses further revealed increased cell cycle entry upon treatment with 5-fluorouracil and reduced granulocyte colony-stimulating factor (GCSF) mobilization of Emcn−/− LT-HSCs, demonstrating that EMCN expression by LT-HSCs associates with quiescence in response to hematopoietic stress and is indispensable for effective LT-HSC mobilization. Transplantation of wild-type bone marrow cells into Emcn−/− or Emcn+/+ recipients demonstrated that EMCN is essential for endothelial cell-dependent maintenance/self-renewal of the LT-HSC pool and sustained blood cell production post-transplant.
Project description:Endomucin (EMCN) currently represents the only hematopoietic stem cell (HSC) marker expressed by both murine and human HSCs. Here, we report that EMCN+ long-term repopulating HSCs (LT-HSCs; CD150+CD48−LSK) have a higher long-term multi-lineage repopulating capacity compared to EMCN− LT-HSCs. Cell cycle analyses and transcriptional profiling demonstrated that EMCN+ LT-HSCs were more quiescent compared to EMCN− LT-HSCs. Emcn−/− and Emcn+/+ mice displayed comparable steady-state hematopoiesis, as well as frequencies, transcriptional programs, and long-term multi-lineage repopulating capacity of their LT-HSCs. Complementary functional analyses further revealed increased cell cycle entry upon treatment with 5-fluorouracil and reduced granulocyte colony-stimulating factor (GCSF) mobilization of Emcn−/− LT-HSCs, demonstrating that EMCN expression by LT-HSCs associates with quiescence in response to hematopoietic stress and is indispensable for effective LT-HSC mobilization. Transplantation of wild-type bone marrow cells into Emcn−/− or Emcn+/+ recipients demonstrated that EMCN is essential for endothelial cell-dependent maintenance/self-renewal of the LT-HSC pool and sustained blood cell production post-transplant.