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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was isolated from the oro/pharyngeal swabs of two Italian COVID-19 patients, physicians in a COVID-19 division hospital, with different courses of the disease. The complete genome sequences show that the two isolates belong to the B1.1 lineage, but contain a nucleotide mutation in the ORF6, leading to a stop codon and to the deletion of 6 amino acids in the C terminus. This deletion was unique, compared to the currently available sequences deposited in the GISAID and GenBank database. It did not affect the in vitro viral replication, neither the neutralizing activities of the patients' antibodies. Based on homology analysis with other Coronaviruses, the two isolated lacked the ORF6 aminoacidic portion responsible for the inhibition of the antiviral Interferon (IFN)-based host response. IFN seems to have a dual role of in SARS-CoV-2 infected patients: not only antiviral activity, but also a detrimental role in case of excessive production. A deletion in the SARS-CoV-2 ORF6 protein might have a specific, still unknown role in the viral pathogenesis.

The present research study reports the development of plastic antibodies based on Molecularly Imprinted Polymers (MIPs) capable of selectively binding a portion of the novel coronavirus SARS-CoV-2 spike protein. Indeed, molecular imprinting represents a very promising and attractive technology for the synthesis of MIPs characterized by specific recognition abilities for a target molecule. Given these characteristics, MIPs can be considered tailor-made synthetic antibodies obtained by a templating process. After in silico analysis, imprinted nanoparticles were synthesized by inverse microemulsion polymerization and their ability to prevent the interaction between ACE2 and the receptor-binding domain of SARS-CoV-2 was investigated. Of relevance, the developed synthetic antibodies are capable of significantly inhibiting virus replication in Vero cell culture, suggesting their potential application in the treatment, prevention and diagnosis of SARS-CoV-2 infection.

Colon cancer is the third cause of cancer death in the developed countries. Some environmental factors are involved in its pathogenesis, including viral infections. The possible involvement of human polyomaviruses (HPyVs) in colon cancer pathogenesis has been previously reported, leading to inconsistent conclusions. Clinical specimens were collected from 125 colon cancer patients. Specifically, 110 tumor tissues, 55 negative surgical margins, and 39 peripheral blood samples were analyzed for the presence of six HPyVs: JC polyomavirus (JCPyV), BK polyomavirus (BKPyV), Merkel cell PyV (MCPyV), HPyV -6, -7, and -9 by means of DNA isolation and subsequent duplex Real Time quantitative polymerase chain reaction. HPyVs genome was detected in 33/204 samples (16.2%): the significant higher positivity was found in tumor tissues (26/110, 23.6%), followed by negative surgical margins (3/55, 5.5%, p < .05), and peripheral blood mononuclear cells (PBMCs) (4/39; 10.3%). HPyVs load was statistically higher only in the tumor tissues compared to negative surgical margins (p < .05). Specifically, MCPyV was detected in 19.1% (21/110) of tumor tissues, 3.6% (2/55) of negative surgical margins (p < .05), and 7.7% (3/39) of PBMCs; HPyV-6 in 2.7% (3/110) of tumor tissues, and 1.8% (1/55) of negative surgical margins; one tumor tissue (1/110, 0.9%) and one PBMCs sample (1/39, 2.6%) were positive for BKPyV; JCPyV was present in 0.9% (1/110) of tumor tissues. HPyV-7 and 9 were not detected in any sample. High prevalence and load of MCPyV genome in the tumor tissues might be indicative of a relevant rather than bystander role of the virus in the colon tumorigenesis.

Objective Progressive multifocal leukoencephalopathy (PML) is still burdened by high mortality in a subset of patients, such as those affected by hematological malignancies. The aim of this study was to analyze the safety and carry out preliminary evaluation of the efficacy of polyomavirus JC (JCPyV)-specific T cell therapy in a cohort of hematological patients with PML. Methods Between 2014 and 2019, 9 patients with a diagnosis of "definite PML" according to the 2013 consensus who were showing progressive clinical deterioration received JCPyV-specific T cells. Cell lines were expanded from autologous or allogenic peripheral blood mononuclear cells by stimulation with JCPyV antigen-derived peptides. Results None of the patients experienced treatment-related adverse events. In the evaluable patients, an increase in the frequency of circulating JCPyV-specific lymphocytes was observed, with a decrease or clearance of JCPyV viral load in cerebrospinal fluid. In responsive patients, transient appearance of punctate areas of contrast enhancement within, or close to, PML lesions was observed, which was interpreted as a sign of immune control and which regressed spontaneously without the need for steroid treatment. Six of 9 patients achieved PML control, with 5 alive and in good clinical condition at their last follow-up. Interpretation Among other novel treatments, T cell therapy is emerging as a viable treatment option in patients with PML, particularly for those not amenable to restoration of specific immunity. Neurologists should be encouraged to refer PML patients to specialized centers to allow access to this treatment strategy. ANN NEUROL 2021;89:769-779.

Background Inhaled particles have been shown to produce systemic changes in DNA methylation. Global hypomethylation has been associated to viral sequence reactivation, possibly linked to the activation of pro-inflammatory pathways occurring after exposure. This observation provides a rationale to investigate viral sequence (both exogenous and endogenous) methylation in association to metal-rich particulate matter exposure. To verify this hypothesis, we chose the Wp promoter of the Epstein-Barr Virus (EBV-Wp) and the promoter of the human-endogenous-retrovirus w (HERV-w), respectively as a paradigm of an exogenous and an endogenous retroviral sequence, to be investigated by bisulfite PCR Pyrosequencing. We enrolled 63 male workers in an electric furnace steel plant, exposed to high level of metal-rich particulate matter. Results Comparing samples obtained in the first day of a work week (time 0-baseline, after 2 days off work) and the samples obtained after 3 days of work (time 1-post exposure), the mean methylation of EBV-Wp was significantly higher at baseline compared to post-exposure (meanbaseline = 56.7%5mC; meanpost-exposure = 47.9%5mC; p-value = 0.009), whereas the mean methylation of HERV-w did not significantly differ. Individual exposure to inhalable particles and metals was estimated based on measures in all working areas and time spent by the study subjects in each area. In a regression model adjusted for age, body mass index and smoking, PM and metal components had a positive association with EBV-Wp methylation (i.e. PM10: β = 5.99, p-value Conclusions The difference observed comparing baseline and post-exposure samples may be suggestive of a rapid change in EBV methylation induced by air particles, while correlation between EBV methylation and PM/metal exposure may represent a more stable adaptive mechanism. Future studies investigating a larger panel of viral sequences could better elucidate possible mechanisms and their role in pro-inflammatory pathways leading to systemic health effects.

JC virus (JCV) is a widespread member of the Polyomaviridae family. Following primary infection, which occurs asymptomatically during childhood, JCV establishes latency in the host. JCV seroprevalence can reach 80 % in healthy adults, but the age of viral exposure has not been yet characterized. This study was conducted to define JCV seroprevalence in Italian infants and to estimate the date of primary infection. A JCV viral protein 1 (VP1)-GST fusion protein was used in conjunction with a homemade indirect enzyme-linked immunosorbent assay (ELISA) to test for the presence of IgG antibodies to JCV in 981 serum samples collected from 644 Italian infants of different ages (1 day to 3 years old) and in 102 breast milk samples. IgM antibody presence was also evaluated in longitudinally collected samples from 17 selected children. JCV antibody prevalence and normalized optical density (nOD) were calculated. For the longitudinal analysis, generalized estimating equation techniques and spline functions were used to estimate the possible non-linear effects of time on antibody production kinetics. JCV IgG was detected in 71.8 % of the sera. Prevalence increased over time from 46.1 % (1 month old) to 80.7 % (12 months old), 85.9 % (24 months old), and 85.5 % (36 months old). As determined by nOD, the longitudinal analysis of serum IgG amounts in children of this study (ages 1 day to 3 years old) illustrated IgG kinetic changes with statistically significant trends (p = 0.001). One-month-old children were largely negative for JCV IgM (82.4 %), and 58.8 % of children produced JCV IgM within the second and sixth months of life. JCV IgG was detected in 27.3 % of breast milk samples. JCV primary infection likely occurs before 6 months of age, and a sizeable percentage of Italian infants will become JCV seropositive within 2 years of age. This study can be used to determine the optimal age for potential future JCV vaccination in infants.

The picture of dynamic interaction between oncogenic viruses and the vaginal bacteria-immune host milieu is incomplete. We evaluated the impact of Polyomaviridae, Papillomaviridae, and Herpesviridae oncoviruses on the vaginal Community State Types (CSTs) and host immune response in reproductive-age women. In our cohort, only Polyomaviridae and Papillomaviridae were detected and were associated with changes in the resident bacteria of CST I and IV (p &lt, 0.05). Lactobacillus crispatus increased in CST I while Prevotella timonensis and Sneathia sanguinegens increased in CST IV. Conversely, CST II and III showed an alteration of the immune response, with the decrease of Eotaxin, MCP-1, IL-7, IL-9, and IL-15 (p &lt, 0.05), leading to reduced antiviral efficacy. An efficient viral clearance was observed only in women from CST I, dominated by Lactobacillus crispatus. Our in vivo study begins to address the knowledge gap with respect to the role of vaginal bacteria and immune response in susceptibility to oncoviral infections.

Background: Viral infections of the anal/rectal tract of men who have sex with men (MSM) have been poorly studied. Methods: In total, 158 swab samples (81 anal/rectal, 65 throat/oral and 12 urethral) were collected from 126 MSM. DNA was isolated and subjected to real-time PCR assays for the detection of the sexually transmitted (ST) pathogens Chlamydia trachomatis, Neisseria gonorrhoeae and Mycoplasmas ssp, human papillomavirus (HPV) and six human polyomaviruses (HPyVs, JCPyV, BKPyV, Merkel cell PyV&ndash, MCPyV-, HPyV-6, HPyV-7 and HPyV-9). Results: C. trachomatis (31/126, 24.6%) and M. genitalium (30/126, 23.8%) were the most frequently detected ST pathogens. Thirty-one/126 (24.6%) patients were positive for at least one HPyV. The significantly (p &lt, 0.05) prevalent HPyV in the anal tract was MCPyV, which was amplified in 27/81 (33.3%) samples, followed by HPyV-6, which was amplified in 6/81 (7.4%) swabs. Coinfections with MCPyV and C. trachomatis or Mycoplasmas were found in 4/21 (19.0%) and 5/21 (23.8%) anal/rectal swabs, respectively. Three/4 MCPyV-C. trachomatis coinfected patients were symptomatic. Conclusions: Based on the high prevalence of MCPyV in the anal/rectal swabs from MSM patients and on the well-known oncogenic properties of MCPyV, sexual transmission and possible involvement of HPyVs in the pathogenesis of diseases of the anal canal should be further studied.

Prostate cancer (PCa) is the most common male neoplasms in the Western world. Various risk factors may lead to carcinogenesis, including infectious agents such as polyomavirus BK (BKPyV), which infects the human renourinary tract, establishes latency, and encodes oncoproteins. Previous studies suggested that BKPyV plays a role in PCa pathogenesis. However, the unspecific tropism of BKPyV and the lack of in vitro models of BKPyV-infected prostate cells cast doubt on this hypothesis. The aim of the present study was to determine whether BKPyV could (a) infect normal and/or tumoral epithelial prostate cells and (b) affect their phenotype. Normal epithelial prostate RWPE-1 cells and PCa PC-3 cells were infected with BKPyV for 21 days. Cell proliferation, cytokine production, adhesion, invasion ability, and epithelial-to-mesenchymal transition (EMT) markers were analyzed. Our results show that (a) RWPE-1 and PC-3 cells are both infectable with BKPyV, but the outcome of the infection varies, (b) cell proliferation and TNF-α production were increased in BKPyV-infected RWPE-1, but not in PC-3 cells, (c) adhesion to matrigel and invasion abilities were elevated in BKPyV-infected RWPE-1 cells, and (d) loss of E-cadherin and expression of vimentin occurred in both uninfected and infected RWPE-1 cells. In conclusion, BKPyV may change some features of the normal prostate cells but is not needed for maintaining the transformed phenotype in the PCa cells The fact that RWPE-1 cells exhibit some phenotype modifications related to EMT represents a limit of this in vitro model.

Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Ureaplasma parvum, Ureaplasma urealyticum, Mycoplasma hominis and Mycoplasma genitalium are established or presumed as (??) STI pathogens. The present study aims at ng describing the one-year molecular epidemiology of these seven pathogens in the Province of Bolzano, Northern Italy. From April 2016 to March 2017, a total of 2,949 patients, mainly females, were enrolled and 3,427 urine, vaginal, endocervical and/or urethral samples were subjected to simultaneous analysis of the seven pathogens by means of Real Time Polymerase Chain Reaction (AnyplexTM II STI-7 Detection Kit Seegene, Seoul, Korea). At least one of the seven microorganisms was detected in 40.7% of patients, with an uneven distribution: 43.1% in females (F) and 29.8% (p

In immunosuppressed patients, BKPyV-variants emerge carrying rearranged non-coding control-regions (rr-NCCRs) that increase early viral gene region (EVGR) expression and replication capacity. BKPyV also encodes microRNAs, which have been reported to downregulate EVGR-encoded large T-antigen transcripts, to decrease viral replication in infected cells and to be secreted in exosomes. To investigate the interplay of NCCR and microRNAs, we compared archetype- and rr-NCCR-BKPyV infection in cell culture. We found that laboratory and clinical rr-NCCR-BKPyV-strains show higher replication rates but significantly lower microRNA levels than archetype virus intracellularly and in exosomes. To investigate whether rr-NCCR or increased EVGR activity modulated microRNA levels, we examined the (sp1-4)NCCR-BKPyV, which has an archetype NCCR-architecture but shows increased EVGR expression due to point mutations inactivating one Sp1 binding site. We found that microRNA levels following (sp1-4)NCCR-BKPyV infection were as low as in rr-NCCR-variants. Thus, NCCR rearrangements are not required for lower miRNA levels. Accordingly, Sp1 siRNA knock-down decreased microRNA levels in archetype BKPyV infection but had no effect on (sp1-4)- or rr-NCCR-BKPyV. However, rr-NCCR-BKPyV replication was downregulated by exosome preparations carrying BKPyV-microRNA prior to infection. To explore the potential relevance in humans, urine samples from 12 natalizumab-treated multiple sclerosis patients were analysed. In 7 patients, rr-NCCR-BKPyV were detected showing high urine BKPyV loads but low microRNAs levels, whereas the opposite was seen in 5 patients with archetype BKPyV. We discuss the results in a dynamic model of BKPyV replication according to NCCR activity and exosome regulation, which integrates immune selection pressure, spread to new host cells and rr-NCCR emergence.

Introduction Inhaled particulate pollutants have been shown to produce systemic changes in DNA methylation. Global hypomethylation has been associated to viral sequence reactivation, possibly linked to the activation of pro-inflammatory pathways occurring after exposure. We aimed at evaluating the effects of PM exposure on DNA methylation of the Wp promoter of the Epstein-Barr Virus (EBV-Wp) and the promoter of the human-endogenous-retrovirus w (HERV-w), chosen as a paradigm of an exogenous virus and an endogenous retroviral sequence, in workers in an electric furnace steel plant with well-characterised exposure to metal-rich particulate matter. Methods We measured EBV-Wp and HERV-w DNA methylation through bisulfite PCR Pyrosequencing on peripheral blood leukocytes DNA obtained from 63 male healthy workers, on the first day of a work week (baseline, after 2 days off work) and after 3 days of work (post-exposure). We determined individual exposure to inhalable particles and metals for all subjects. Paired t-test was used to compare baseline and post-exposure samples. Linear mixed models were fitted to evaluate the association between metal-rich particle exposure and DNA methylation. Results Comparing samples obtained at baseline and after 3 days of work, the mean methylation of EBV-Wp was significantly higher at baseline compared to post-exposure (baseline=56.7; postexposure=47.9; p-value=0.009), whereas the mean methylation of HERV-w did not significantly differ. In a regression model adjusted for age, body mass index and smoking, nickel, arsenic and lead had a positive association with EBV-Wp methylation (nickel: β=16.16, p-value Conclusions The difference observed comparing baseline and postexposure samples may be suggestive of a rapid change in EBV methylation induced by air particles, while correlation between EBV methylation and metal exposure may represent an adaptive mechanism that should be further characterised in future investigations.

Progressive multifocal leukoencephalopathy (PML) is a devastating and often fatal demyelinating disease of the central nervous system for which effective therapies are lacking. It is caused by the replication of polyomavirus JC (JCV) in the oligodendrocytes and astrocytes leading to their cytolytic death and loss of myelin from the subcortical white matter. While the virus is very common in human populations worldwide, the incidence of the disease is very low and confined almost exclusively to individuals with some form of immunological dysfunction. However, the number of people who constitute the at-risk population is growing larger and includes individuals with HIV-1/AIDS and patients receiving immunomodulatory therapies such as multiple sclerosis patients treated with natalizumab. Further adding to the public health significance of this disease are the difficulties encountered in the diagnosis of PML and the lack of useful biomarkers for PML progression. In this review, we examine the diagnostic assays that are available for different aspects of the JCV life cycle, their usefulness and drawbacks, and the prospects for improvements.

BK polyomavirus (BKV) has a worldwide seroprevalence of approximately 90%. After primary infection, BKV establishes a life-long latency within the urogenital tract. The severe immunological impairment occurring in renal transplant recipients leads to BKV reactivation, which may result in polyomavirus associated nephropathy (PVAN). While the transplanted kidney is transiently unperfused, Hypoxia Inducible Factors (HIFs) mediate the cellular response to hypoxia. The α-subunit of HIF isoform 1 (HIF-1α) may interact with several viruses, but until now, there has been no information regarding the interaction between BKV and HIF-1α. The aim of this study is to investigate the possible interaction between HIF-1α and BKV and its potential effect on the pathogenesis of PVAN. Screening of 17 kidney tissue samples revealed that HIF-1α expression was 13.6-fold higher in PVAN tissues compared to control tissues. A luminometric assay in co-transfected African green monkey kidney cells (VERO) demonstrated BKV promoter activation ranging from two to sixfold (P

Background In light of their regulatory role, changes in the expression of Polyomavirus JC (JCPyV) microRNAs may be relevant for virus reactivation and the development of progressive multifocal leukoencephalopathy (PML). Objectives To investigate the presence of JCPyV-DNA and JCPyV microRNA expression in clinical specimens of patients at risk for PML. Study design The JCPyV-DNA and microRNA status was assessed in peripheral blood mononuclear cells (PBMCs) and plasma from 100 HIV patients, in serum and cerebrospinal fluid (CSF) from 14 HIV PML patients and in PBMCs and plasma from 50 healthy controls using Multiplex real-time PCR and JCPyV miRNA-J1-3p and −5p stem-loop RT-PCR. The JCPyV-DNA microRNA-expressing region was also sequenced. Results A positive JCPyV-DNA status was more prevalent in HIV patients (67%, 67/100) compared to healthy controls (18%, 9/50). Among these, 46% and 42% of the HIV patients and 18% and 0% of the healthy controls were positive based on PBMC and plasma determinations, respectively. PBMC JCPyV microRNA positivity was observed in 22 out of 46 (48%) JCPyV+ HIV patients and in 3 out of 9 (33%) JCPyV+ healthy controls. Moreover, JCPyV microRNAs in exosomes were found in 6 out of 100 (6%) HIV plasma samples, in 12 out of 50 (24%) healthy samples, in 6 out of 14 (43%) serum samples, and in 3 out of 5 (60%) HIV PML CSF samples. Of note, the JCPyV-DNA load was inversely correlated with expression of the viral microRNA. The JCPyV microRNA genomic expression region showed a different combination of three mutations. Conclusions The low levels of JCPyV microRNA expression in HIV patients with high JCPyV-DNA prevalence observed in this study highlight the potential clinical relevance of JCPyV microRNAs in PML risk assessment.

Several studies associating BK polyomavirus (BKPyV) and prostate cancer (PCa) suggested that this virus may exert its oncogenic activity at early stages of cancer development. The BKPyV oncogene, the large T antigen (LTag), has frequently been detected in areas of proliferative inflammatory atrophy, which is considered a precursor lesion leading to prostatic intraepithelial neoplasia and overt PCa. In a recently updated systematic review, the presence of BKPyV was significantly higher in PCa tissues than in healthy control tissues, providing an indication for a link between BKPyV infection and cancer risk. In addition, recent original investigations highlighted an association between expression of the virus and the clinical course of PCa. For example, by studying immune responses elicited against BKPyV LTag, a significant association between LTag positive cancer lesions and a peculiar regulatory profiling has been observed in PCa patients with evidence of disease recurrence after surgical radical prostatectomy. Lastly, a study carried out in a larger cohort of patients undergoing radical prostatectomy revealed the IgG response against LTag as an independent predictor of disease recurrence. Although a full picture of the mechanisms potentially responsible for the involvement of BKPyV in PCa is not available yet, continuing work on this topic should help to refine the potential role of BKPyV in PCa patients, perhaps revealing unsuspected associations with the clinical course of this disease.

Background Leukoencephalopathies in HAART-treated, HIV-positive patients include progressive multifocal leukoencephalopathy (PML), a result of lytic infection oligodendrocytes by JC polyomavirus (JCV), and another form characterized by the absence of JCV genome in cerebrospinal fluid (CSF). Objectives To test the potential viral etiology of JCV-negative leukoencephalopathy. Study design CSF was collected from 43 HIV-positive patients with MRI suggestive of leukoencephalopathies. DNA was isolated and real-time PCR assays for neurotropic viruses (Herpes Simplex Viruses 1/2, Varicella Zoster Virus, Epstein Barr Virus, Human Cytomegalovirus, Human Herpesvirus 6, JCV and HIV) were conducted. CSF from 14 non-reactive cases were subjected to random nucleic acid amplification, deep sequencing, and in silico search for viral sequences. Results JCV genome was detected in the CSF of 19/43 PML patients, HIV genome in the CSF of 5 PML patients including 2 JCV negative patients, and no viruses were detected in 22 patients. Human Polyomavirus 6 (HPyV6) DNA was detected by deep sequencing in one JCV-negative leukoencephalopathy CSF sample. Conclusions HPyV6 DNA was detected in CSF of a case of demyelinating disease. HPyV6 has not been previously reported in CSF or associated with any disease. Demonstrating a causative role will require further studies.

About 40 years ago, the large and small tumor antigens (LT-Ag and sT-Ag) of the polyomavirus (PyVs) simian vacuolating virus 40 have been identified and characterized. To date, it is well known that all the discovered human PyVs (HPyVs) encode these 2 multifunctional and tumorigenic proteins, expressed at viral replication early stage. The 2 T-Ags are able to transform cells both in vitro and in vivo and seem to play a distinct role in the pathogenesis of some tumors in humans. In addition, they are involved in viral DNA replication, transcription, and virion assembly. This short review focuses on the structural and functional features of the HPyVs’ LT-Ag and sT-Ag, with special attention to their transforming properties.

Background: Polyomavirus (PyV) infection is common, ranging from 60% to 100% depending on the virus. The urinary excretion rates of JC virus (JCV) and BK virus (BKV) have been extensively studied, but less is known about the more recently discovered PyVs. Objectives: To investigate the urinary excretion of Merkel cell PyV (MCPyV), which is associated with Merkel cell carcinoma (MCC), in kidney transplant recipients and healthy subjects, as well as those of lymphotropic polyomavirus (LPV), which was isolated from the B-cells of African green monkeys but has also been found in human blood, JCV and BKV. Study design: Urine samples were collected from 62 adult (ATP) and 46 pediatric (PTP) kidney transplant recipients and from 67 adult (AHC) and 40 pediatric (PHC) healthy controls. DNA was isolated and analyzed using real-time PCR (Q-PCR) to determine the viral loads of MCPyV, LPV, JCV and BKV. Results: MCPyV DNA was more frequently detected (p

Extracellular vesicles (EVs) are important components of the metastatic niche and are crucial in infiltration, metastasis, and immune tolerance processes during tumorigenesis. We hypothesized that human endogenous retroviruses (HERV) positive EVs derived from tumor cellsmay have a role in modulating the innate immune response. The study was conducted in two different colorectal cancer cell lines, representing different stages of cancer development: Caco-2, derived from a non-metastatic colorectal adenocarcinoma, and SK-CO-1, derived from metastatic colorectal adenocarcinoma (ascites). Both cell lines were treated with decitabine to induce global hypomethylation and to reactivate HERV expression. EVs were quantified by nanoparticle tracking analysis, and HERV-positive EV concentrations were measured by flow cytometry. The effect of EVs isolated from both untreated and decitabine-treated cells on the innate immune response was evaluated by injecting them in zebrafish embryos and then assessing Interleukin 1&beta, (IL1-&beta, ), Interleukin 10 (IL-10), and the myeloperoxidase (mpx) expression levels by real-time qPCR. Interestingly, HERV-K positive EVs concentrations were significantly associated with a reduced expression of IL1-&beta, and mpx, supporting our hypothesis that HERV-positive EVs may act as immunomodulators in tumor progression. The obtained results open new perspectives about the modulation of the immune response in cancer therapy.

JC virus (JCV) and BK virus (BKV) belong to the Polyomaviridae family and were the first human polyomaviruses (PyVs) discovered. Both JCV and BKV remain latent in the kidneys and can reactivate in immunocompromised hosts, causing progressive multifocal leukoencephalopathy (PML) and nephropathy, respectively. PyVs induce cell transformation in vitro and in animal models, where they infect non-permissive cells. The molecular mechanisms of tumor formation are based on the large tumor antigen (T Ag) protein, which is able to bind and inactivate pRb and p53, inducing uncontrolled cell cycle progression. Many studies on clinical samples also indicate a positive association between JCV and BKV and human solid tumors; however no direct involvement of PyVs in the development of human cancers has been demonstrated. In this review we focused on the potential association between JCV and BKV with brain and urinary tract tumors, respectively.

Very little is known about JCV infection and genotype distribution with respect to the different demographic and clinical characteristics of the Italian population. A cross-sectional study was carried out on the prevalence of JCV genotypes in 323 Caucasian subjects (mean age: 37.5 years, range: 2-70 years). Urine samples from 200 immunocompromised patients, including patients affected by Multiple Sclerosis (MS), Human Immunodeficiency Virus (HIV), colon cancer, inflammatory diseases and Progressive Multifocal Leukoencephalopathy (PML), and 123 immunocompetent individuals were tested by quantitative real time PCR. Sequencing of the JCV viral protein 1 (VP1) and transcriptional control region (TCR) was performed. In this series, the overall prevalence of JCV excretion was 32.8% without significant differences between males and females. JCV was detected in 39.5% of patients and in 22% of healthy individuals (P = 0.004). The most prevalent JCV genotype excreted was genotype 1 (69.8%), followed by genotype 2 (22.6%) and genotype 4 (7.5%). Distribution of genotypes between patients and healthy subjects showed a statistically significant difference for the type 1 compared to the other variants (P

Almost one fifth of human cancers worldwide are associated with infectious agents, either bacteria or viruses, and this makes the possible association between infections and tumors a relevant research issue. We focused our attention on the human Polyomavirus JC (JCPyV), that is a small, naked DNA virus, belonging to the Polyomaviridae family. It is the recognized etiological agent of the Progressive Multifocal Leukoencephalopathy (PML), a fatal demyelinating disease, occurring in immunosuppressed individuals. JCPyV is able to induce cell transformation in vitro when infecting non-permissive cells, that do not support viral replication and JCPyV inoculation into small animal models and non human primates drives to tumor formation. The molecular mechanisms involved in JCPyV oncogenesis have been extensively studied: the main oncogenic viral protein is the large tumor antigen (T-Ag), that is able to bind, among other cellular factors, both Retinoblastoma protein (pRb) and p53 and to dysregulate the cell cycle, but also the early proteins small tumor antigen (t-Ag) and Agnoprotein appear to cooperate in the process of cell transformation. Consequently, it is not surprising that JCPyV genomic sequences and protein expression have been detected in Central Nervous System (CNS) tumors and colon cancer and an association between this virus and several brain and non CNS-tumors has been proposed. However, the significances of these findings are under debate because there is still insufficient evidence of a casual association between JCPyV and solid cancer development. In this paper we summarized and critically analyzed the published literature, in order to describe the current knowledge on the possible role of JCPyV in the development of human tumors.

Progressive multifocal leukoencephalopathy (PML) is a severe disease of the central nervous system (CNS), caused by infection with the Polyomavirus JC virus (JCV). Because there are no known treatments or prognostic factors, we performed a long-term study focusing mainly on cerebrospinal fluid (CSF) samples from PML patients to describe the virological features akin to the different forms of the disease. Twenty-eight PML patients were enrolled: 10 HIV-1+ patients with classical PML (CPML), 9 HIV-1+ patients with slowly progressing or stable neurological symptoms (benign PML), 3 HIV-1+ asymptomatic patients and 6 HIV-1-negative patients. CSF, urine and blood samples were collected at the enrollment (baseline) and every six months afterwards when possible. The JCV DNA and HIV-1 RNA loads were determined, and the JCV strains were characterized. At baseline , the mean CSF JCV load was log 6.0 ± 1.2 copies/ml for CPML patients, log 4.0 ± 1.0 copies/ml for benign PML patients, log 4.2 ± 0.5 copies/ml for asymptomatic PML patients and log 5.8 ± 1.3 copies/ml for HIV-1-negative PML patients (CPML versus benign: p

Viral infections of the central nervous system (CNS) are associated with an increased risk for seizures during the acute infection period and the subsequent development of chronic epilepsy that is often difficult to treat. In previous work, we have shown that mice of the C57BL/6 strain infected with Theiler's murine encephalomyelitis virus (TMEV) exhibit a similar sequence, thereby providing a potential useful model of virus-induced epilepsy. The present study examines spontaneous and miniature excitatory postsynaptic currents in CA3 pyramidal cells recorded from brain slices prepared during both the acute phase during encephalitis and 2 months following TMEV infection. Animals that develop chronic epilepsy following TMEV infection exhibit considerable hippocampal sclerosis, directly implicating this brain region in the process of epileptogenesis. There are significant increases in amplitude and frequency of spontaneous and miniature excitatory currents in CA3 cells recorded in brain slices prepared during the acute infection period and 2 months after infection. However, the patterns of changes observed are markedly different during these two periods, suggesting that there are underlying changes in the network over time. These differences have implications for the treatment used during the acute infection and after chronic seizures develop.

Atherosclerosis is a complex, multifactorial disease. Several studies have reported a possible association between infection with microbial agents and atherogenesis. Chlamydia pneumoniae ( C. pneumoniae), Herpes Simplex Virus 1 (HSV1), Human Cytomegalovirus (HCMV), and Epstein Barr Virus (EBV) have been widely investigated for their possible role in atherosclerosis development, but the results obtained to date are contradictory. The aim of our study is to search DNA of the aforementioned infectious agents by means of Quantitative Real Time PCR in atherosclerotic plaques from carotid arteries obtained from 17 patients. Genomic sequences of C. pneumoniae, HSV1, HCMV were not found in any atherosclerotic lesion. Therefore, our results do not support the hypothesis of an association between these infectious agents and atherosclerosis. Conversely, three patients were found to be positive for EBV DNA, thus indicating that, at least in a limited number of patients, EBV could play a role in atherogenesis.

HIV-related acute inflammatory leukoencephalopathy of undetermined origin (AIL) has been anecdotally described in literature as being responsible for cognitive and motor deficits. We carried out a review of all the cases of AIL published in literature. Articles were selected according to 2 criteria: acute onset of symptoms; undetermined aetiology and non-fulfilment of multiple sclerosis diagnostic criteria. They were then analyzed in terms of clinical, biological and instrumental features, therapy, diagnostic classification and prognosis. Although rare (21 patients out of about 4,000 publications), AIL is of particular interest, as the comprehension of its mechanisms could give some insight into the direct and immune-mediated actions of HIV within the brain. All the reported patients share several clinical, histopathological, radiological and CSF features, leading to hypothesize a similar aetiopathogenetic mechanism. Conversely, we observed a high heterogeneity of treatment and diagnostic classification, which could have conditioned the broad prognostic variability. The absence of a defined aetiology leads to consider these forms as a particular subgroup of “not determined leucoencephalopathies” (NDLE), with both MRI and histological pattern dominated by inflammation as distinctive feature.

The major capsid protein, VP1, of the human Polyomavirus BK (BKV) is structurally divided into five outer loops, referred to as BC, DE, EF, GH, and HI. The BC loop includes a short region, named the BKV subtyping region, spanning nucleotides 1744–1812 and characterized by non-synonymous nucleotide polymorphisms that have been used to classify different strains of BKV into four subtypes. The aim of this study was to determine if the nucleotide changes clustered within the BKV subtyping region may influence the in vitro growth efficiency of the virus. We therefore infected the African Green Monkey kidney cell line Vero with four different viral strains (named BKV I, II, III, and IV) that contained the nucleotide sequences of the BKV subtypes within the same genomic background. Infected cells were followed for 59 days and viral replication was assessed at different time points by Quantitative Real Time PCR (Q-PCR). BKV I, II, and IV were successfully propagated over time in Vero cells, whereas BKV III viral loads progressively decreased during the infection course, demonstrating that the non-synonymous nucleotide polymorphisms of subtype III confer a strong disadvantage for viral replication. Since subtype III differs from all the other subtypes at position 68 of the VP1, where Leu is replaced by Gln, we created viral strains bearing Gln at this position together with the polymorphisms of subtypes I, II, IV and tested their growth in Vero cells. Our results demonstrate that this amino acid substitution does not lower the replication efficiency of subtypes I, II, and IV. In conclusion, this study provides further insights to the importance of the BC loop of BKV in the virus life cycle. In addition, given the effect of the amino acid substitutions of the four BKV subtypes on infectious spread of the virus, our results suggest the need to investigate their potential association with BKV related complications.

Polyomavirus-associated nephropathy (PVAN) is a major complication that occurs after renal transplantation and is induced by reactivation of the human polyomavirus BK (BKV). The structure of the viral capsid protein 1 (VP1) is characterized by the presence of external loops, BC, DE, EF, GH, and HI, which are involved in receptor binding. The pathogenesis of PVAN is not well understood, but viral risk factors are thought to play a crucial role in the onset of this pathology. In an attempt to better understand PVAN pathogenesis, the BKV-VP1 coding region was amplified, cloned, and sequenced from the urine of kidney transplant recipients who did, and did not, develop the pathology. Urine viral loads were determined by using real time quantitative PCR (Q-PCR). Amino acid substitutions were detected in 6/8 patients, and 6/7 controls. The BC and EF loop regions were most frequently affected by mutations, while no mutations were found within the GH and HI loops of both patients and controls. Some mutations, that were exclusively detected in the urine of PVAN patients, overlapped with previously reported mutations, although a correlation between changes in amino acids and the development of PVAN was not found. Urine viral loads were higher than that of the proposed cut-off loads for identification of patients that are at a high risk of developing PVAN (10(7) copies/ml), both in the PVAN and control groups, thus confirming that urine viral load is not a useful predictive marker for the development of PVAN.

JC virus (JCV) is a human polyomavirus that causes progressive multifocal leukoencephalopathy (PML), a fatal demyelinating disease that mainly affects immunocompromised subjects. Since its discovery, PML has been considered a rapidly progressing fatal disease; however, amino acid substitutions in the capsid viral protein have recently been tentatively associated with changes in PML clinical course. In order to provide more insight to PML pathogenesis and identify potential prognostic markers, seven cerebrospinal fluid (CSF) samples and four brain autopsy samples were collected from patients afflicted with PML with different clinical courses (fast- and slow-progressing), and the JCV VP1 coding region was amplified, cloned, and sequenced. In addition, urine samples were collected and analyzed from nine patients with PML or other neurological diseases (ONDs) as a control group. Sequencing analysis of the genomic region encoding the VP1 outer loops revealed polymorphic residues restricted to four positions (74, 75, 117, and 128) in patients with slow PML progression, whereas no significant mutation was found in JCV isolated from urine. Collectively, these data show that JCV VP1 loop mutations are associated with a favorable prognosis for PML. It is therefore possible that slower progression of PML may be related to the emergence of a less virulent JCV strain with a lower replication rate.

JC virus (JCV) is a polyomavirus that asymptomatically infects up to 80% of the worldwide human population and establishes latency in the kidney. In the case of host immunodeficiency, it can cause progressive multifocal leukoencephalopathy (PML), which is a fatal demyelinating disease of the central nervous system. In an attempt to understand better PML pathogenesis and JCV infection, the presence of the JCV genome and expression of the early viral protein in the brain of deceased individuals, with and without HIV infection, was investigated. Sixty autopsy samples of brain tissues were collected from 15 HIV-positive PML patients, 15 HIV-positive patients with other neurological diseases, 15 HIV-positive patients without neurological disorders, and 15 HIV-negative individuals who died from diseases unrelated to the central nervous system. By means of specific Real Time Polymerase Chain Reaction, the JCV genome was detected in 14 of 15 PML brains, three of 15 HIV-positive brains (with and without neurological diseases), and 1 of 15 HIV-negative brains. JCV genotyping was also performed. Expression of the early JCV protein T Antigen was verified by a specific immunohistochemistry assay, and it was found in the brain tissues from 12 PML cases and one case with other neurological disease. The data obtained demonstrate that infection of the brain with JCV can also be observed in the brains of HIV-negative individuals, without neurological disorders. However, viral protein expression was limited to PML brains and to one brain from a patient with other neurological disease, suggesting that JCV can also be present in the brains of patients without PML.

Following the development of progressive multifocal leukoencephalopathy (PML) in two multiple sclerosis (MS) patients treated with natalizumab and interferon-beta (IFNbeta), a possible correlation between JC virus (JCV), the etiological agent of PML, and MS has received heightened interest. In particular, attention has focused on assessing whether IFNbeta treatment could affect the replication of JCV and thus its frequency in the peripheral blood of MS patients and whether the presence of JCV DNA in peripheral blood could be a predictive marker of the risk of developing PML. In order to answer to these questions, peripheral blood samples were collected from 59 INFbeta-treated, 39 untreated relapsing-remitting MS patients, and 98 healthy controls (HCs) and JCV DNA levels were determined and quantified by means of a real-time polymerase chain reaction (Q-PCR) assay. Overall, no differences were found in the presence or viral load of JCV DNA of MS patients and the HCs, but JCV DNA was significantly less frequent in the peripheral blood of IFNbeta-treated patients (13.6%) compared to the untreated MS patients (46.1%) and the healthy controls (28.6%). These results suggest that the presence of JCV in the blood of MS patients cannot be considered as a marker or a risk factor for PML development. In addition, they indicate that treatment with INFbeta can lead to the reduction of presence of the JCV genome in the peripheral blood of MS patients and, thus, that this drug probably does not increase the risk of PML in MS patients treated with IFNbeta.

Progressive multifocal leukoencephalopathy (PML) usually is a rapid and fatal demyelinating disease of the central nervous system (CNS), caused by JC virus (JCV). After the introduction of Highly active antiretroviral therapy (HAART), its prognosis has been modified in some cases but remains a relevant cause of morbidity in human immunodeficiency virus-seropositive (HIV+) patients. The authors report here two cases of PML, followed over time, sharing a benign course and a JCV antigen-specific T-cell response, but with different cerebrospinal fluid (CSF), magnetic resonance imaging (MRI), and clinical features. In both cases, JCV DNA detection in brain biopsies samples and specific antigenic response preceded its isolation in the CSF by several months. In one patient, during the first stage of the disease, the presence of CSF and MRI inflammatory findings, associated with the lack of JCV detection in the CSF, made the diagnosis more challenging. Given that to date a reformation of the laboratory parameters for PML diagnosis is strongly needed, this report highlights the following considerations: (a) indications for performing brain biopsy in HIV-related leukoencephalopathies of uncertain origin, and (b) the role of JCV immunologically specific T-cell response as an additional marker for PML diagnosis and indicator for good prognosis of the disease.

In order to investigate the possible involvement of viruses in Multiple Sclerosis (MS), the study evaluated the presence of viral genomic sequences in cerebrospinal fluid (CSF), as markers of viral replication within the central nervous system (CNS). A total of 85 CSF samples were collected from 38 MS patients, 28 patients with other neurological diseases and 19 subjects without neurological diseases. Using nested-PCR, the investigation focused on the presence of human herpes virus DNA, including herpes simplex virus 1 (HSV-1) and 2 (HSV-2), the Epstein-Barr virus (EBV), varicella zoster virus (VZV), human cytomegalovirus (HCMV), human herpes virus 6 (HHV-6) and JC virus (JCV). All the CSF samples from the individuals without neurological diseases were negative for viral DNA. Genomic sequences of HSV-1, HCMV, EBV, HHV6, and JCV were found in patients with MS and other neurological diseases without significant differences between the two groups. VZV DNA was detected more frequently (P < 0.05) in the MS group (31.6%), particularly among the relapsing-remitting MS patients (43.5%), compared with patients with other neurological diseases (10.7%). In addition, the results indicated that JCV and HHV-6 were replicating actively in the CNS of a small, but significant number of patients with MS and other neurological diseases. Most importantly, the study revealed a high frequency of VZV DNA in the CSF of patients with MS, suggesting a possible role of this virus in the pathogenesis of MS.

JC virus (JCV) is the etiological agent of progressive multifocal leukoencephalopathy (PML), a fatal demyelinating disease of the central nervous system (CNS). During the acquired immunodeficiency syndrome (AIDS) epidemic, it was the cause of the death in up to 8% of AIDS patients. The genomic organization of JCV and, in particular, the hypervariability of the transcriptional control region (TCR), a regulatory noncoding region, are well known. Given that the TCR plays a central role in the viral replication of JCV, a crucial role in the determination of the neurotropism and in the pathogenic capabilities of the virus is also suspected. Here the authors describe a case of PML that did not respond to highly active antiretroviral therapy (HAART) therapy. There was a simultaneous presence of JCV strains with four different TCR structures in urine, peripheral blood cells, serum, and cerebrospinal fluid (CSF) samples. These data confirmed that the presence of the archetype TCt is restricted to urine, while also suggesting that the degree of the rearrangement varies and increases from the peripheral blood to CSF.

The etiology of brain tumors and meningiomas is still unknown. Several factors have been considered, such as genetic predisposition and environmental risk factors, but the hypothesis that one or more infectious agents may play a role in tumor pathogenesis has also been investigated. Therefore, emphasis was placed on the neurooncogenic family Polyomaviridae and the presence of human polyomavirus DNA sequences and JCV mRNA were examined in malignant human brain biopsies. Italian patients affected with different types of neoplasias of the brain and its covering were enrolled. The patients underwent surgical tumor excision and the presence of the polyomavirus genome in biopsy and other body fluids was evaluated by PCR. In addition, the genomic organization of JCV was examined in depth, with the aim of providing information on genotype distribution and TCR rearrangements in the population affected with intracranial neoplasms. On the whole, polyomavirus DNA was found in 50% of the biopsy specimens studied, JC virus DNA and BK virus DNA were amplified in 40.6% mainly glioblastomas and 9.4% of the tissue specimens, respectively, while none of the biopsy specimens tested contained Simian virus 40 DNA. Genotype 1 and Mad 4 TCR organization were the most frequent in the population enrolled. Although a cause and effect was not demonstrated and the specific role of the viruses remains unknown, the findings appear to confirm the hypothesis that JCV and BKV could be important co-factors in tumor pathogenesis. J. Med. Virol. 77:447–454, 2005. © 2005 Wiley-Liss, Inc.

Multiple sclerosis (MS) is a chronic inflammatory autoimmune disease of the central nervous system. Natalizumab, a humanized anti-α4 integrin monoclonal antibody, is a highly effective treatment approved for MS. An association between MS and an exposure to Epstein-Barr Virus (EBV) sustained by the levels of antiviral capsid antigen (VCA) and anti-Epstein-Barr nuclear antigen-1 (EBNA-1) IgG has been described. Our goal was to verify the utility of EBV-specific IgG as a marker in Natalizumab treated MS. Twenty patients (17 female and 3 male) in treatment with Natalizumab were enrolled. Serum levels of anti-VCA and anti-EBNA-1 IgG were determined and expressed as arbitrary units (AU) before treatment and every three months for 21 months of therapy. Anti-VCA IgG levels were increased at the 15th month (235410 ± 196712 AU) comparing with the 3rd (98146 ± 47145 AU) and the 6th (109866 ± 52270 AU) months of therapyp<0.05. No significant differences were found for serum anti-EBNA-1 IgG levels. Our data indicate that a transient, self-limited, EBV reactivation can occur in MS during Natalizumab therapy but our results do not support the use of serum EBV-specific antibody levels as biomarkers for monitoring therapeutic response to Natalizumab in the course of MS.

Background: The human neurotropic polyomavirus, JCV, contains an open reading frame within the late region of the viral genome that encodes a 71-amino-acid protein, agnoprotein. Because accumulating evidence supports an association between JCV infection and human brain tumors, including medulloblastomas, we assessed the presence of JCV Agno gene sequences and the expression of agnoprotein in a series of 20 well-characterized medulloblastomas. Methods: Formalin-fixed, paraffin-embedded tumor tissue samples were used for Agno gene amplification and for immunohistochemical analysis. Adjacent sections were stained with an antibody to agnoprotein and with antibodies to cellular structural and regulatory proteins, including the JCV early gene product, T antigen. Results: Analysis of amplified DNA from paraffin-embedded samples revealed the presence of the Agno gene in 11 (69%) of 16 samples. Immunohistochemical analysis showed cytoplasmic localization and widespread distribution of agnoprotein in the neoplastic cells in 11 (55%) of 20 samples. The JCV early gene product, T antigen, was present in the nucleus of some, but not all, of the neoplastic cells. Some medulloblastoma samples that expressed agnoprotein had no sign of T-antigen expression, p53 was detected in only six of the 11 tumors in which agnoprotein was expressed. None of the 20 samples showed expression of the viral late capsid proteins, ruling out productive infection of the tumor cells with JCV. Conclusions: Our data provide evidence that the JCV late gene encoding the auxiliary agnoprotein is expressed in tumor cells. The finding of agnoprotein expression in the absence of T-antigen expression suggests a potential role for agnoprotein in pathways involved in the development of JCV-associated medulloblastomas.

The risk of developing progressive multifocal leukoencephalopathy (PML), as a consequence of infection/reactivation with JC virus (JCV), is consistent in natalizumab-treated multiple sclerosis (MS) patients, with 430 cases of PML reported so far. The risk of PML is higher in JCV seropositive patients, and it is recommended that only MS patients without JCV antibodies should be enrolled in the treatment postulating that they do not have JCV infection. We have studied forty-two natalizumab-treated MS patients, and urine and blood were collected monthly for up to 60 months. JCV and BK virus (BKV) DNA presence was verified using quantitative real-time PCR assays, and serum anti-JCV antibodies were measured with the Stratify and/or Stratify DxSelect tests. JCV and BKV DNA were not found in the blood samples, whereas they were found at least once in the urine of 21 of 42 (50 %) and of 25/42 (59.5 %) patients, respectively. JCV DNA urinary shedding increased up to month 24 of natalizumab treatment (45.2 %), and the effect of time was significant for JCV (p = 0.04), but not for BKV (p = 0.39). JCV viruria and seropositivity did not completely correlate, since three patients shedding JCV DNA in the urine were seronegative according to the serological tests. The results indicated that natalizumab therapy may increase the rate of JCV urinary shedding. Additionally, we confirmed that the identification of JCV carriers cannot solely rely on serological tests, but sensitive methods for viral DNA detection should be adopted to more precisely identify the truly JCV uninfected cases.

West Nile virus (WNV) is a flavivirus that causes neurological disorders in less than 1 % of infected subjects. Human cases of WNV-associated fever and/or neurological disorders have been reported in Italy since 2008. The first outbreak occurred in the northeastern region of Italy surrounding the Po River and was caused by the Po River lineage 1 strain, and since then, WNV infections have been reported in several regions of central Italy. Although the virus is highly genetically conserved, stochastic mutations in its genome may lead to the emergence of new strains, as was observed in Italy in 2011 with the identification of two new lineage 1 strains, the WNV Piave and WNV Livenza strains. To help further define WNV epidemiology in Italy, we describe a case of an Italian man living in the Po River area who developed fatal encephalitis in 2009 due to infection with the WNV Piave strain. This finding supports the notion that the Piave strain has been circulating in this area of Italy for 2 years longer than was previously believed.

Prostate cancer (PCA) is the most frequent cancer in men. Exposure to infectious agents has been reported to have a putative role in tumorigenesis. Among the infectious agents, convincing evidence has been accumulated about the human polyomavirus BK (BKV). Tissue fresh specimens, serum, and urine samples were collected from 124 consecutive patients, 56 with PCA and 68 with benign prostatic hyperplasia (BPH). Quantitative PCR assays were used to assess the presence of BKV and JC virus (JCV) genomes. BKV-positive tissue specimens were found in 32.1 and 22.1 % of PCA and BPH patients, respectively; in PCA group the number of positive BKV specimens/patients was significantly higher than in BPH group (3.06 vs. 1.73, p = 0.02). JCV genome was found in the biopsies collected from 28.1 and 24.2 % of PCA and BPH patients, respectively, with no significant difference in the rate of JCV specimens/patients between PCA and BPH groups. Our results support the putative causal association between BKV genome and PCA. Further studies are required to demonstrate the direct pathogenetic role of BKV in the PCA occurrence and progression in order to clear the tempting way of vaccine prophylaxis.

Treatment with biological drugs is associated with increased susceptibility to viral infections. Reactivation of JC virus (JCV) and human cytomegalovirus (HCMV) in adults after therapy has been documented. The long-term effects of biological and conventional therapy on human herpesviruses and polyomaviruses infections in young patients were assessed. One hundred eighty-six samples [urine, serum, and blood cells (PBMCs)] from 62 patients (15.8 ± 6.2 years old) with Crohn's disease, ulcerative rectocolitis or juvenile rheumatoid arthritis treated with immunotherapy or conventional therapy for over 12 months were tested by real time PCR. One hundred twenty-four samples (urine and blood) from 62 matched healthy volunteers (13.8 ± 8.6 years old) were included as controls. Sequencing of the JCV viral protein 1 (VP1) and transcriptional control region (TCR) was performed. Herpes simplex virus 1/2 and varicella zoster virus genomes were not detected in any patients, whereas Epstein-Barr virus, HCMV, and human herpesvirus-6 genomes were detected in 4.8%, 3.2%, and 1.6% of the patients, respectively. JCV was detected in 22.6% (14/62) of urine samples from patients and in 8% (5/62) from controls, in 50% (7/14) of sera from patients shedding JCV, and in 71.4% (5/7) of matched PBMCs. There was a significant association between infliximab treatment and excretion of JCV genotype 2. Subclinical infection/reactivation of JCV genotype 2 in young patients during infliximab therapy was demonstrated. Conversely, increased susceptibility to herpesviruses infection was not shown. Future studies are warranted to investigate the effects of JCV reactivation on the health of young patients treated with infliximab.

The polyomavirus (PyV), JC virus (JCV), is a small nonenveloped DNA virus that asymptomatically infects about 80% of healthy adults and establishes latency in the kidney tissue. In case of immunodeficient hosts, JCV can lytically infect the oligodendrocytes, causing a fatal demyelinating disease, known as progressive multifocal leukoencephalopathy (PML). Although the reactivation of another human PyV, BK virus (BKV), is relatively common and its association with the polyomavirus associated nephropathy (PyVAN) following renal transplantation is proven, JCV replication and its impact on graft function and survival are less well studied. Here we describe the biology of JCV and its pathological features and we review the literature regarding the JCV infection analyzed in the setting of transplantations.

Rituximab is a chimeric monoclonal antibody reacting with the CD20 antigen on B cells. It has been proposed as treatment for the idiopathic nephrotic syndrome, recurrent idiopathic nephropathy, and focal segmental glomerulosclerosis refractory to steroids. Rituximab influences T-cell immunity and may predispose the patients to opportunistic infections, such as progressive multifocal leukoencephalopathy caused by the polyomavirus JC (JCV). The risk of latent viruses infections/reactivations in pediatric patients receiving monoclonal antibodies is not well known yet. In this longitudinal 6-month study, the effects of rituximab on JCV and BK virus (BKV) replication have been investigated. Blood, serum, and urine samples have been collected monthly from 11 pediatric patients (mean age: 11 years) with the idiopathic nephrotic syndrome and recurrent idiopathic nephropathy, under rituximab therapy. JCV and BKV real-time PCRs and sequencing of the viral protein 1 and the non-coding control region have been conducted. The same investigations have been undertaken on samples collected from eight pediatric patients (controls, mean age: 6 years), with idiopathic nephrotic syndrome or focal segmental glomerulosclerosis, treated with conventional chemotherapy. JCV was detected in the urine of one patient (9%), and one control (12.5%); BKV was found in the urine of 7/11 patients (63.6%) and 2/8 controls (25%) and in blood samples from four patients. No significant difference was found in the mean viral loads and in the viral molecular characterizations between the two groups. The polyomaviruses replication was not associated with rituximab therapy in children. J. Med. Virol. 84:1464–1470, 2012. © 2012 Wiley Periodicals, Inc.

The polyomavirus JC virus (JCV) is a small nonenveloped DNA virus that asymptomatically infects about 80% of healthy adults and establishes latency in the kidney tissue. In case of immunodeficient hosts, JCV can lytically infect the oligodendrocytes, causing a fatal demyelinating disease, known as Progressive Multifocal Leukoencephalopathy (PML). Although the reactivation of another human polyomavirus, BK Virus (BKV), is relatively common and its association with the Polyomavirus Associated Nephropathy (PVAN) following renal transplantation is assessed, JCV replication and its impact on graft function and survival is less well studied. In addition, none of the performed studies ruled out the hypothesis that JCV could be associated with certain post-transplantation clinical syndromes. Thus, monitoring of Polyomaviruses infection, especially during the first 24 months post-transplantation, is recommended.

The role of viruses in the pathogenesis of multiple sclerosis (MS) is a subject of heated debate. The presence of six different neurotropic viruses was sought, including JC virus (JCV), varicella zoster virus (VZV), human herpesvirus 6 (HHV-6), and Epstein-Barr virus (EBV), in cerebrospinal fluid (CSF) samples collected from 51 patients with MS and 30 patients with other neurological diseases. Cell-free or cell-associated viral DNA in CSF samples was detected by real-time PCR, and viral loads were determined. Magnetic resonance imaging (MRI) examinations were also performed to look for active lesions. Cell-associated JCV DNA was detected in 3 of the 51 patients with MS and in 2 of the 30 patients with other neurological disease. Cell-free JCV DNA was detected in one additional patient with MS. Cell-free VZV DNA was detected in one patient without MS, cell-free HHV-6 was detected in one patient with MS, and cell-free EBV was detected in one patient with MS. All other study patients had no detectable viral DNA in CSF samples and no double infections were found. The small percentage of patients with detectable viral DNA in CSF samples was comparable between patients with MS and those with other neurological disease, and presence of viral DNA was not a predictor of brain lesions. Additional observations suggest that cell trafficking from the periphery, rather than leakage through the blood-brain barrier, results in the transport of viruses to the CNS, where local immunosurveillance can control viral replication in immunocompetent individuals.

Background: Lymphotropic Polyomavirus (LPV) was isolated from a B-lymphoblastoid cell line of an African green monkey. This virus shares some characteristics with human polyomaviruses, but it is antigenically distinct from BK Virus (BKV) and JC Virus (JCV). Seroepidemiological studies revealed that human sera react in the presence of LPV antigens, and, recently, the viral genome was amplified in the peripheral blood from patients affected with HIV-related leukoencephalopathies. Objectives: The aims of the study were to investigate and compare the presence of LPV DNA with that of JCV and BKV in different biological samples and patient groups. Study design: LPV, JCV and BKV DNA were searched and quantified in peripheral blood and CSF from HIV+ patients and in peripheral blood from healthy subjects. Results: The LPV genome was detected in peripheral blood of both HIV+ patients and healthy subjects, with a prevalence of 7.2% and 4.7% respectively, but not in CSF. However, its presence was less frequent than that of JCV and BKV. Conclusions: The amplification of LPV genome from human peripheral blood confirms the fact that LPV can infect the human population. LPV DNA was amplified from patients affected with HIV-related leukoencephalopathies but also from HIV patients without neurological disorders and from healthy subjects. Therefore, the results do not support the hypothesis of an association between LPV infection and any neurological disease. However, given their high similarity, it is possible that LPV, as well as BKV and JCV, could establish latency in humans and cause disease only in rare circumstances.

Lymphotropic polyomavirus (LPV) was first isolated in 1979 from a B-lymphoblastoid cell line of an African green monkey by zur Hausen and Gissman (10). This virus has some characteristics common to human polyomavirus, such as virion morphology, the presence of a closed circular double-stranded molecule of DNA, and in vitro transforming activity (7), but it is antigenically distinct from simian virus 40, BK virus, and JC virus (1). In cell cultures, LPV has a highly restricted host range for both human and monkey B lymphoblasts (2, 3), and seroepidemiological studies revealed that, in addition to sera from monkeys, many human sera had strong reactions in the presence of LPV antigens (8).

A dynamic equilibrium between proliferation and programmed cell death (PCD) of auto-reactive T lymphocytes plays a pivotal role in the prevention of autoimmune diseases. We analyzed T lymphocytes myelin basic protein (MBP)-specific PCD and proliferation in demyelinating diseases. Results showed that MBP-specific PCD was significantly decreased in CD4+ and CD8+ T lymphocytes of progressive multifocal leukoencephalopathy (PML), not determined leukoencephalopathy (NDLE), and acute MS (AMS) patients compared to patients with stable MS (SMS) and healthy controls. MBP-specific proliferation/PCD rates were high in CD4+ T lymphocytes of PML, NDLE, and AMS patients, and in CD8+ T cells of PML and AMS individuals alone. Alterations of the balance between MBP-specific proliferation and PCD are present in demyelinating diseases and could play a major role in the pathogenesis of these diseases.