[Show abstract][Hide abstract] ABSTRACT: Patients undergoing haematopoietic stem cell transplantation (HSCT) are at high risk of severe gastrointestinal bleeding caused by infections, graft versus host disease, and disturbances in haemostasis. BK polyomavirus (BKPyV) is known to cause hemorrhagic cystitis, but there is also evidence of BKV shedding in stool and its association with gastrointestinal disease. We report putative association of BKPyV replication with high plasma viral loads in a pediatric HSCT patient developing hemorrhagic cystitis and severe gastrointestinal bleeding necessitating intensive care. The observation was based on chart review and analysis of BKPyV DNA loads in plasma and urine as well as retrospective BKPyV-specific IgM and IgG measurements in weekly samples until three months post-transplant. The gastrointestinal bleeding was observed after a >100-fold increase in the plasma BKPyV loads and the start of hemorrhagic cystitis. The BKPyV-specific antibody response indicated past infection prior to transplantion, but increasing IgG titers were seen following BKPyV replication. The gastrointestinal biopsies were taken at a late stage of the episode and were no longer informative of BK polyomavirus involvement. In conclusion, gastrointestinal complications with bleeding are a significant problem after allogeneic HSCT to which viral infections including BKPyV may contribute.
Journal of Clinical Virology 11/2014; · 3.47 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Liver sinusoidal endothelial cells (LSECs) are specialized scavenger cells that mediate high-capacity clearance of soluble waste macromolecules and colloid material, including blood-borne adenovirus. To explore if LSECs function as a sink for other viruses in blood, we studied the fate of virus-like particles (VLPs) of two ubiquitous human DNA viruses, BK and JC polyomavirus, in mice. Like complete virions, VLPs specifically bind to receptors and enter cells, but unlike complete virions, they cannot replicate. 125I-labeled VLPs were used to assess blood decay, organ-, and hepatocellular distribution of ligand, and non-labeled VLPs to examine cellular uptake by immunohisto- and -cytochemistry. BK- and JC-VLPs rapidly distributed to liver, with lesser uptake in kidney and spleen. Liver uptake was predominantly in LSECs. Blood half-life (∼1 min), and tissue distribution of JC-VLPs and two JC-VLP-mutants (L55F and S269F) that lack sialic acid binding affinity, were similar, indicating involvement of non-sialic acid receptors in cellular uptake. Liver uptake was not mediated by scavenger receptors. In spleen, the VLPs localized to the red pulp marginal zone reticuloendothelium, and in kidney to the endothelial lining of vasa recta segments, and the transitional epithelium of renal pelvis. Most VLP-positive vessels in renal medulla did not express PV-1/Meca 32, suggesting location to the non-fenestrated part of vasa recta. The endothelial cells of these vessels also efficiently endocytosed a scavenger receptor ligand, formaldehyde-denatured albumin, suggesting high endocytic activity compared to other renal endothelia. We conclude that LSECs very effectively cleared a large fraction of blood-borne BK- and JC-VLPs, indicating a central role of these cells in early removal of polyomavirus from the circulation. In addition, we report the novel finding that a subpopulation of endothelial cells in kidney, the main organ of polyomavirus persistence, showed selective and rapid uptake of VLPs, suggesting a role in viremic organ tropism.
PLoS ONE 11/2014; 9(11):e111762. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A 15-year-old boy with a posterior urethral valve received a deceased donor kidney transplant (KT) in March 2011. Basiliximab induction followed by tacrolimus-based triple medication was used as immunosuppression. Eleven months after KT, the graft function deteriorated and the biopsy demonstrated interstitial nephritis suggestive of acute rejection. BK polyomavirus (BKPyV) surveillance in urine and plasma was negative. The patient received methylprednisolone pulses and anti-thymocyte globulin. Immunohistochemistry was positive for simian virus 40 (SV40) large T-antigen (LTag) in the biopsies, and quantitative polymerase chain reaction for JC polyomavirus (JCPyV) indicated high viral loads in urine and borderline levels in plasma. Immunosuppression was reduced and follow-up biopsies showed tubular atrophy and interstitial fibrosis. Two years after KT, antibody-mediated rejection resulted in graft loss and return to hemodialysis. Retrospective serologic work-up indicated a primary JCPyV infection with seroconversion first for IgM, followed by IgG, but no indication of BKPyV infection. In the SV40 LTag positive biopsies, JCPyV deoxyribonucleic acid (DNA) with archetype noncoding control region was detected, while BKPyV DNA was undetectable. To the best of our knowledge, this is the first reported case of primary JCPyV infection as the cause of PyV-associated nephropathy in KT.
American Journal of Transplantation 10/2014; · 6.19 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: JC polyomavirus (JCPyV) can cause progressive multifocal leukoencephalopathy (PML), a debilitating, often fatal brain disease in immunocompromised patients. JCPyV-seropositive multiple sclerosis (MS) patients treated with natalizumab have a 2- to 10-fold increased risk of developing PML. Therefore, JCPyV serology has been recommended for PML risk stratification. However, different antibody tests may not be equivalent. To study intra- and inter-laboratory variability, sera from 398 healthy blood donors were compared in 4 independent enzyme-linked immunoassay (ELISA) measurements generating >1592 data points. Three datasets (Basel1, Basel2, Basel3) used the same basic protocol, but different JCPyV virus-like particle (VLP) preparations and introduced normalization to a reference serum. The datasets were also compared with an independent method using biotinylated VLPs (Helsinki1). VLP preadsorption reducing ≥35% activity was used to identify seropositive sera. The results indicated that Basel1, Basel2, Basel3, and Helsinki1 were similar regarding overall data distribution (P=0.79) and seroprevalence (58.0%, 54.5%, 54.8%, 53.5%, respectively; P=0.95). However, intra-assay intra-laboratory comparison yielded 3.7% to 12% discordant results, most of which were close to the cut-off (0.080<OD<0.250) according to Bland-Altman analysis. Introducing normalization improved overall performance and reduced discordance. The inter-laboratory inter-assay comparison between Basel3 and Helsinki1 revealed only 15 discordant results, of which 14 (93%) were close to cut-off. Preadsorption identified specificities of 99.44% and 97.78% and sensitivities of 99.54% and 95.87% for Basel3 and Helsinki, respectively. Thus, normalization to a preferably WHO-approved reference serum, duplicate testing and preadsorption for samples around the cut-off may be necessary for reliable JCPyV-serology and PML risk stratification.
Clinical and vaccine Immunology: CVI 09/2014; · 2.37 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: To the Editor: Boulware et al. (June 26 issue)(1) address the timing of initiation of antiretroviral therapy (ART) for human immunodeficiency virus-associated cryptococcal meningitis, and they conclude that excess mortality in association with "earlier ART" was probably due to the immune reconstitution inflammatory syndrome (IRIS). However, they reported no significant difference in the incidence of IRIS between the two groups (P=0.32). Another explanation could be that more participants had elevated intracranial pressure at diagnosis in the earlier-ART group than in the deferred-ART group (58% vs. 51%). If the 24 participants in whom intracranial pressure was not measured at diagnosis are . . .
New England Journal of Medicine 09/2014; 371(12):1165-1167. · 54.42 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The presence of minority nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistant HIV-1 variants prior to antiretroviral therapy (ART) has been linked to virologic failure in treatment-naive patients.
AIDS (London, England) 07/2014; 28(15). · 6.56 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Gastrointestinal infections are caused by a broad spectrum of pathogens. Conventional diagnostic procedures are resource and time consuming due to single pathogen testing, often in different laboratories.
[Show abstract][Hide abstract] ABSTRACT: Previous studies have associated activating Killer cell Immunoglobulin-like Receptor (KIR) genes with protection from cytomegalovirus (CMV) replication after organ transplantation. Whether KIR-associated protection is operating in the context of primary infection, re-activation, or both, remains unknown. Here we correlated KIR genotype and CMV serostatus at the time of transplantation with rates of CMV viremia in 517 heart (n=57), kidney (n=223), liver (n=165) or lung (n=72) allograft recipients reported to the Swiss Transplant Cohort Study. Across the entire cohort we found B haplotypes-which in contrast to A haplotypes may contain multiple activating KIR genes-to be protective in the most immunosuppressed patients (receiving anti-thymocyte globulin induction and intensive maintenance immunosuppression) (hazard ratio after adjustment for covariates 0.46, 95% confidence interval 0.29-0.75, P=0.002). Notably, a significant protection was detected only in recipients who were CMV-seropositive at the time of transplantation (HR 0.45, 95% CI 0.26-0.77, P=0.004), but not in CMV seronegative recipients (HR 0.59, 95% CI 0.22-1.53, P=0.28). These data indicate a prominent role for KIR-and presumably natural killer (NK) cells-in the control of CMV replication in CMV seropositive organ transplant recipients treated with intense immunosuppression.Genes and Immunity advance online publication, 10 July 2014; doi:10.1038/gene.2014.39.
[Show abstract][Hide abstract] ABSTRACT: Rationale: Invasive fungal disease (IFD) is a significant cause of morbidity and mortality in immunocompromised patients. Objectives: We hypothesize that galactomannan, a component of fungal cell wall, as measured in the bronchoalveolar lavage (BAL-GM) might be a diagnostic adjunct in hematological malignancies. Methods: 568 hematological cases undergoing diagnostic bronchoscopy due to respiratory symptoms and/or suspected IFD between 2009 and 2013 at a tertiary care center in Switzerland were included in this prospective, observational cohort study. We compared accuracy of the BAL-GM ELISA determination in predicting IFD as classified by the EORTC/MSG definition. Measurements and Main Results: BAL-GM was positive in 155 cases (29.2%). According to the EORTC/MSG criteria, IFD was classified as possible in 182 (34.3%), probable in 45 (8.5%) and proven 6 (1.1%). BAL-GM provided 50% sensitivity, 73.0% specificity, 16% PPV, and 93% NPV for diagnosing proven+probable IFD. Results were similar when antifungal treatment and radiologic suspicion of IFD were used as the gold standard. The AUC of the ROC curve (AUC) for the diagnosis of proven+probable IFD was 0.716 (95%CI 0.638-0.794, p<0.001). Conclusions: Galactomannan in the BAL had modest agreement with EORTC/MSG criteria for diagnosing invasive fungal disease in immunocompromised patients with a high degree of antifungal exposure.
American Journal of Respiratory and Critical Care Medicine 07/2014; · 11.99 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: No reliable treatment options are known for progressive multifocal leukoencephalopathy with underlying immunodeficiency. We describe successful compassionate use of recombinant human interleukin 7 in a patient with idiopathic CD4+ T-cell lymphocytopenia.
[Show abstract][Hide abstract] ABSTRACT: The human fetal glial cell line SVG was generated in 1985 by transfecting primary fetal brain cells with a plasmid containing an origin-defective mutant of simian virus 40 (SV40). The cells, which express SV40 large T-antigen, support the replication of human JC polyomavirus (JCPyV) and have been used for JCPyV studies but also for other studies where cells of neural origin were desirable. We intended to use the SVG p12 cells from ATCC for antiviral drug studies with JCPyV. However, during initial experiments, immunofluorescence microscopy controls unexpectedly revealed cells expressing the late viral proteins VP1, VP2/VP3 and agno. This was confirmed by western blotting. Since the agnoprotein antiserum is specific for BKPyV-agnoprotein, infection with BKPyV was suspected. Indeed specific BKPyV PCR of SVG p12 supernatants revealed a viral load of >1×10(10) genomic equivalents/ml. Negative staining electron microscopy showed characteristic polyomavirus virions and infectious BKPyV was transmitted from SVG p12 supernatant to other cells. Long-range PCR covering the viral genome followed by DNA sequencing, identified BKPyV strain UT as well as deletion derivatives. This was confirmed by next generation sequencing. JCPyV (MAD-4) was found to infect apparently uninfected and BKPyV-infected SVG p12 cells. In total, 4 vials from 2 different ATCC lots of SVG p12 cells dating back to 2006 contained BKPyV, whereas the subclone SVG-A was negative. In conclusion, SVG p12 cells from ATCC contain infectious BKPyV. This may have affected results and interpretation of previous studies and caution should be taken in future experiments.
This work reveals that one of the most frequently used cell lines for JC polyomavirus (JCPyV) research, the SV40-immortalized human fetal glial cell line SVG obtained directly from ATCC, contains infectious BK polyomavirus (BKPyV) of UT strain and a spectrum of defective mutants. The UT strain has been previously found in urine and in tumours of different patients but is also frequently used for research. It is therefore not clear if BKPyV was present in the brain tissue used to generate the cell line or if this is a contamination. Although a productive JCPyV of SVG cells was not dependent on prior BKPyV infection, the unknown BKPyV infecton may have influenced the results of studies performed in these cells. However, the frequently used subclone SVG-A did not contain BKPyV. The interpretation of past results should therefore be reconsidered and cells tested for BKPyV before new studies are initiated.
[Show abstract][Hide abstract] ABSTRACT: B-cells in airways and lung parenchyma may be involved in COPD evolution. However, whether their pathogenic role is beneficial or harmful remains controversial. The objective of this study was to investigate the maturation of adenovirus-specific immunoglobulins in COPD patients in respect to clinical outcome.
The presence of adenovirus-specific immunoglobulins during acutely exacerbated COPD (AECOPD) was analyzed at exacerbation and 2-3 weeks later. Patients with detectable adenovirus-specific IgM and low IgG avidity were grouped into fast and delayed IgG maturation. The clinical outcome of both groups was evaluated.
Out of 208 patients, 43 patients (20.7%) had serologic evidence of recent adenovirus infection and were grouped into 26 patients with fast IgG maturation and 17 patients with delayed IgG maturation. Baseline characteristics, AECOPD therapy, and duration of hospitalization were similar in both groups. However, the AECOPD recurrence rate within six months was higher (p = 0.003) and there was a trend for earlier AECOPD related re-hospitalizations (p = 0.061) in patients with delayed IgG maturation. The time to re-hospitalization or death within two years was shorter in patients with delayed IgG maturation (p = 0.003). Adenovirus-specific IgG maturation was an independent predictor of both, the number of recurrent AECOPDs within six months (p = 0.001) and the occurrence of hospitalization or death within two years (p = 0.005).
Delayed immunoglobulin avidity maturation, following COPD exacerbation, is associated with worse outcome.
[Show abstract][Hide abstract] ABSTRACT: BK polyomavirus (BKPyV) infection is widespread and typically asymptomatic during childhood, but may cause nephropathy in kidney transplant recipients. However, there is only limited knowledge on BKPyV-specific immunity in children and adults, and its role in BKPyV-replication and disease posttransplant. We therefore characterized BKPyV-specific immunity from 122 immunocompetent individuals (1–84 years), 38 adult kidney recipients with (n = 14) and without BKPyV-associated complications (n = 24), and 25 hemodialysis (HD) patients. Blood samples were stimulated with overlapping peptides of BKPyV large-T antigen and VP1 followed by flow-cytometric analysis of activated CD4 T cells expressing interferon-γ, IL-2 and tumor necrosis factor-α. Antibody-levels were determined using enzyme-linked immunosorbent assay. Both BKPyV-IgG levels and BKPyV-specific CD4 T cell frequencies were age-dependent (p = 0.0059) with maximum levels between 20 and 30 years (0.042%, interquartile range 0.05%). Transplant recipients showed a significantly higher BKPyV-specific T cell prevalence (57.9%) compared to age-matched controls (21.7%) or HD patients (28%, p = 0.017). Clinically relevant BKPyV-replication was associated with elevated frequencies of BKPyV-specific T cells (p = 0.0002), but decreased percentage of cells expressing multiple cytokines (p = 0.009). In conclusion, BKPyV-specific cellular immunity reflects phases of active BKPyV-replication either after primary infection in childhood or during reactivation after transplantation. Combined analysis of BKPyV-specific T cell functionality and viral loads may improve individual risk assessment.
American Journal of Transplantation 04/2014; · 6.19 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report on a 65-year-old male patient with a Shiga-toxin producing Escherichia coli O51:H49 gastrointestinal infection and sepsis associated with hemolytic uremic syndrome (HUS) with a fatal outcome. The strains isolated harbored stx2e and eae, a very unusual and new virulence profile for a HUS-associated enterohemorrhagic E. coli.
Journal of clinical microbiology 02/2014; · 4.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Cytomegalovirus (CMV) is the most frequent infectious complication following solid organ transplantation (SOT). The virus, in this population, is responsible for both direct (viral syndrome, hepatitis, pneumonitis, colitis…) and indirect effects (rejection, infections by other microorganisms and graft dysfunction). In this evidence-based guideline we dealt with the most important aspects of CMV infection in SOT recipients, including pre and post-transplant diagnosis assessment, risk factors with special emphasis in the prevention and treatment of this viral infection. Overall, an adequate management of CMV infection is a critical aspect in transplant patient care. This article is protected by copyright. All rights reserved.
Clinical Microbiology and Infection 02/2014; · 4.58 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Community-acquired respiratory viruses (CARVs) are a frequent cause of disease in solid-organ transplant (SOT) recipients. Lower respiratory tract infections with CARV can be associated with significant morbidity and even mortality in this population. The impact of CARV infections on the progression of chronic allograft dysfunction in lung transplant recipients remains controversial. This article is protected by copyright. All rights reserved.
Clinical Microbiology and Infection 02/2014; · 4.58 Impact Factor