Project description:BK polyomavirus (BKPyV) is a small DNA virus that establishes a life-long persistent infection in the urinary tract of most people. BKPyV is known to cause severe morbidity in renal transplant recipients and can lead to graft rejection. The simple 5.2 kilobase pair dsDNA genome expresses just seven known proteins, thus it relies heavily on host machinery to replicate. How the host proteome changes over the course of infection is key to understanding this host:virus interplay. Here for the first time quantitative temporal viromics has been used to quantify global changes in >9,000 host proteins in two types of primary human epithelial cell throughout 72 hours of BKPyV infection. These data demonstrate the importance both of cell cycle progression and pseudo-G2 arrest in effective BKPyV replication, along with a surprising lack of innate immune response throughout the whole virus replication cycle. BKPyV thus evades pathogen recognition to prevent activation of innate immune responses in a sophisticated manner.
Project description:JC polyomavirus (JCPyV) established a persistent infection, but BK polyomavirus (BKPyV) killed the cells in 15 days. To identify the cellular factors responsible for controlling JCPyV infection and promoting viral persistence, we profiled the transcriptomes of JCPyV- and BKPyV-infected cells at several time points postinfection. We found that interferon-stimulated genes (ISGs) were only activated in the JCPyV and not in the BKPyV-infected cells.
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: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.
2013-05-23 | GSE47199 | GEO
Project description:BK Polyomavirus Persistence, Genome Recombination, and Reactivation
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:Vesicoureteral reflux (VUR) is a common pediatric condition that predisposes children to renal damage after urinary tract infection (UTI). We profiled the urinary proteome of VUR patients with recurrent UTI and renal scarring to identify potential biomarkers characterizing this condition. Urine was obtained from 22 age-matched controls and 22 patients with low grade VUR (1-3 out of 5), renal scarring, and history of recurrent UTI. Proteins extracted from these samples were analyzed by mass spectrometry for protein identification and quantitation for comparison.