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JC virus identified in a patient with persistent and severe West Nile virus disease
Abstract
West Nile virus is a notable cause of neuroinvasive disease, damage to the central nervous system, or even death. In this study, using metagenomics analysis and quantitative real-time PCR validation, we identified a JC virus infection in urine and cerebrospinal fluid samples of a West Nile virus patient with severe neurological symptoms and extended disease. JC virus is known to be involved in neurological complications, especially in immunocompromised individuals thus suggesting that the coinfection with JC virus is involved with the West Nile virus infection persistence and severe symptoms. JC virus was identified in urine samples from additional West Nile virus patients via quantitative real-time PCR, however, JC virus was not found in any cerebrospinal fluid samples of West Nile virus patients, suggesting that JC virus does not regularly infect the central nervous system of WNV patients. Overall, this study highlights the importance of identifying infection by opportunistic viruses in already-diagnosed patients and highlights the advantages of next-generation sequencing and metagenomics for viral diagnosis.
JC polyomavirus (JCPyV), a ubiquitous human pathogen, causes several devastating brain diseases in immune‐compromised individuals. The most notable of these JCPyV‐associated CNS diseases is the frequently fatal demyelinating brain disease progressive multifocal leukoencephalopathy (PML). PML, an AIDS‐defining disease in the pre‐cART epoch, has emerged as a life‐threatening complication in patients receiving immunomodulatory agents for autoimmune and inflammatory disorders and treatment for certain hematological malignancies. Among the rapidly expanding list of PML‐associated biologics, natalizumab (Tysabri®) has the highest incidence and is an ominous sequela for multiple sclerosis (MS) patients who otherwise benefit from dramatic reductions in relapses using this immunomodulatory agent. Drug withdrawal, the only therapeutic option for PML, is often complicated by a high‐mortality cerebral inflammatory reaction. No anti‐JCPyV agents are available. Lack of a tractable animal model of polyomavirus‐induced central nervous system (CNS) disease is an acknowledged bottleneck to elucidating PML pathogenesis, immunological mechanisms that control JCPyV, in vivo evaluation of agents that inhibit polyomavirus replication in tissue culture, and uncovering early events that presage JCPyV‐associated neuropathology. The natural virus–host mouse polyomavirus (MuPyV) model has recently been developed to explore mechanisms of polyomavirus‐associated CNS disease. In this review, we will cover the benefits of using the MuPyV model to answer fundamental questions about innate and adaptive immune control of JCPyV, the impact of immunomodulation on JCPyV pathogenesis, and how this MuPyV CNS infection model will help improve criteria for identifying patients at risk for JCPyV‐associated CNS diseases before the development of irreversible lesions.
A mutation leading to substitution of a key amino acid in the prM protein of West Nile virus (WNV) occurred during persistent infection of an immunocompetent patient. WNV RNA persisted in the patient’s urine and serum in the presence of low-level neutralizing antibodies. This case demonstrates active replication of WNV during persistent infection.
The current diagnosis of West Nile Virus (WNV) infection is primarily based on serology since molecular identification of
WNV RNA is unreliable due to the short viremia and absence of detectable virus in cerebrospinal fluid (CSF). Recent studies
have shown that WNV RNA can be detected in urine for a longer period of time and at higher concentrations than plasma. Here,
we examined the presence of WNV RNA in serum, plasma, whole blood, CSF and urine samples obtained from acute WNV infection
diagnosed patients during an outbreak which occurred in Israel in 2015. Our results demonstrate that 33 of 38 WNV patients
had detectable WNV RNA in whole blood at the time of diagnosis, a higher rate than detection of WNV RNA in any of the other
sample types tested. Overall, whole blood was superior to all other samples with 86.8% sensitivity, 100% specificity, 100%
positive predictive value and 83.9% negative predictive value. Interestingly, WNV viral load in urine was higher than in whole
blood, CSF, serum and plasma despite the lower sensitivity compared to whole blood. This study establishes the utility of
whole blood in the routine diagnosis of acute WNV infection and suggests that it may provide the highest sensitivity for WNV
RNA detection in suspected cases.
The human genome contains about 8% of endogenous retroviral sequences originated from germ cell infections by exogenous retroviruses during evolution. Most of those sequences are inactive because of accumulation of mutations but some of them are still capable to be transcribed and translated. The latter are insertionally polymorphic HERV-K113 and HERV-K115. It has been suggested that their presence and expression was connected with several human diseases. It is also believed that they could interfere with the replication cycle of exogenous retroviruses, including HIV.
Prevalence of endogenous retroviral sequences HERV-K113 and HERV-K115 was determined in the Polish population. The frequencies were found as 11.8% for HERV-K113 and 7.92% for HERV-K115. To verify the hypothesis that the presence of these HERVs sequences could affect susceptibility to HIV infection, comparison of a control group (HIV-negative, not exposed to HIV; n = 303) with HIV-positive patients (n = 470) and exposed but uninfected (EU) individuals (n = 121) was performed. Prevalence of HERV-K113 and HERV-K115 in the EU group was 8.26% and 5.71%, respectively. In the HIV(+) group we detected HERV-K113 sequences in 12.98% of the individuals and HERV-K115 sequences in 7.23% of the individuals. There were no statistically significant differences between groups studied.
The frequency of HERV-K113 and HERV-K115 sequences in Poland were found to be higher than usually shown for European populations. No relation between presence of the HERVs and HIV infection was detected.
West Nile virus (WNV) RNA was demonstrated in 5 (20%) of 25 urine samples collected from convalescent patients 573–2452 days
(1.6–6.7 years) after WNV infection. Four of the 5 amplicons sequenced showed >99% homology to the WNV NY99 strain. These
findings show that individuals with chronic symptoms after WNV infection may have persistent renal infection over several
years
Thymomas are the only tumors that are proven to generate mature T cells from immature precursors. It is unknown, however, whether intratumorous thymopoiesis has an impact on the peripheral T-cell pool and might thus be related to the high frequency of thymoma-associated myasthenia gravis. This study shows, using fluorescence-activated cell sorting-based analyses and T-cell proliferation assays, that thymopoiesis and T-cell function in thymomas correspond with immunologic alterations in the blood. Specifically, the proportion of circulating CD45RA(+)CD8(+) T cells is significantly increased in patients with thymoma compared with normal controls, in accordance with intratumorous T-cell development that is abnormally skewed toward the CD8(+) phenotype. Moreover, it is primarily the proportion of circulating CD45RA(+)CD8(+) T cells that decreases after thymectomy. The results also demonstrate that T cells reactive toward recombinant autoantigens are distributed equally between thymomas and blood, whereas T-cell responses to foreign antigen (ie, tetanus toxoid) are seen only among circulating T cells and not among thymoma-derived T cells. These functional studies support the hypothesis that thymopoiesis occurring within thymomas alters the peripheral T-cell repertoire. Because many thymomas are enriched with autoantigen-specific T cells, a disturbance of circulating T-cell subset composition by export of intratumorous T cells may contribute to paraneoplastic autoimmune disease arising in patients with thymoma. (Blood. 2000;96:3872-3879)
Infection with West Nile virus (WNV) causes fatal encephalitis more frequently in immunocompromised humans than in those with
a healthy immune system. Although a complete understanding of this increased risk remains unclear, experiments with mice have
begun to define how different components of the adaptive and innate immune response function to limit infection. Previously,
we demonstrated that components of humoral immunity, particularly immunoglobulin M (IgM) and IgG, have critical roles in preventing
dissemination of WNV infection to the central nervous system. In this study, we addressed the function of CD8+ T cells in controlling WNV infection. Mice that lacked CD8+ T cells or classical class Ia major histocompatibility complex (MHC) antigens had higher central nervous system viral burdens
and increased mortality rates after infection with a low-passage-number WNV isolate. In contrast, an absence of CD8+ T cells had no effect on the qualitative or quantitative antibody response and did not alter the kinetics or magnitude of
viremia. In the subset of CD8+-T-cell-deficient mice that survived initial WNV challenge, infectious virus was recovered from central nervous system compartments
for several weeks. Primary or memory CD8+ T cells that were generated in vivo efficiently killed target cells that displayed WNV antigens in a class I MHC-restricted
manner. Collectively, our experiments suggest that, while specific antibody is responsible for terminating viremia, CD8+ T cells have an important function in clearing infection from tissues and preventing viral persistence.
West Nile virus (WNV) causes epidemics of febrile illness, meningitis, encephalitis, and flaccid paralysis. Since it was first detected in New York City in 1999, and through 2004, >16,000 WNV disease cases have been reported in the United States. Over the past 5 years, research on WNV disease has expanded rapidly. This review highlights new information regarding the virology, clinical manifestations, and pathology of WNV disease, which will provide a new platform for further research into diagnosis, treatment, and possible prevention of WNV through vaccination.
Thymomas are the only tumors that are proven to generate mature T cells from immature precursors. It is unknown, however, whether intratumorous thymopoiesis has an impact on the peripheral T-cell pool and might thus be related to the high frequency of thymoma-associated myasthenia gravis. This study shows, using fluorescence-activated cell sorting-based analyses and T-cell proliferation assays, that thymopoiesis and T-cell function in thymomas correspond with immunologic alterations in the blood. Specifically, the proportion of circulating CD45RA+CD8+ T cells is significantly increased in patients with thymoma compared with normal controls, in accordance with intratumorous T-cell development that is abnormally skewed toward the CD8+ phenotype. Moreover, it is primarily the proportion of circulating CD45RA+CD8+ T cells that decreases after thymectomy. The results also demonstrate that T cells reactive toward recombinant autoantigens are distributed equally between thymomas and blood, whereas T-cell responses to foreign antigen (ie, tetanus toxoid) are seen only among circulating T cells and not among thymoma-derived T cells. These functional studies support the hypothesis that thymopoiesis occurring within thymomas alters the peripheral T-cell repertoire. Because many thymomas are enriched with autoantigen-specific T cells, a disturbance of circulating T-cell subset composition by export of intratumorous T cells may contribute to paraneoplastic autoimmune disease arising in patients with thymoma.
Background:
New clinical approaches to diagnose and monitor individuals with systemic diseases have been employed through the use of oral fluids. Polyomavirus BK (BKPyV) and JC (JCPyV) infect asymptomatically around 80% of general population worldwide remaining latent in the body. In case of immunosuppression, a replication can occur, leading to diseases.
Objective:
The aim of this study was to detect and quantify BKPyV and JCPyV in oral fluids of individuals with chronic kidney failure (CKF), kidney transplantation (KT) and controls compared with their detection in blood and urine, traditionally used for this test.
Study design:
Forty six subjects were included and distributed into 3 groups: 14 with CKF (Group 1), 12 with KT (Group 2) and 20 healthy individuals (Group 3). In a total, 315 samples were collected and analyzed through RT-PCR, being 151 of gingival crevicular fluid, 46 of saliva, 46 of mouthwash, 43 of blood and 29 of urine.
Results:
All subjects from group 1 were positive for BKPyV in at least one collected samples and 14% were positive for JCPyV. In Group 2, 91.7% were positive for BKPyV and 51.7% for JCPyV. Among subjects of Group 3, 80% were positive for BKPyV and 45% for JCPyV.
Conclusions:
Oral fluids exhibited high prevalence of BKPyV and JCPyV and were equally efficient compared to urine and blood. The use of oral fluids to detect these polyomaviruses enhances positivity in screening, even in cases of absence of viremia and especially in individuals who are not able to urinate.
In healthy individuals John Cunningham virus is latent without any clinical signs, but in the cases of the use of immunosuppressive drugs in graft recipients, autoimmune diseases and also increasing of age, that the immune system is suppressed it may cause disease in reactivation. Progressive multifocal leukoencephalopathy (PML) is the well-known disease caused by the virus. It has also been associated with nephropathy and tumorogensis. At present, based on vp1 capsid gene 7 genotypes have been detected. Genetic variations of JC virus in different geographical areas and the presence of different subtypes is a useful tool for reconstructing of the genetic information of JC virus and understanding of its evolution. The aim of this study was to investigate different genotypes of the JC virus in the urine of 100 kidney transplant recipients, 43 rheumatoid arthritis patients and 100 healthy individuals as control group in Isfahan. DNA was extracted by phenol-chloroform method and subjected to a nested PCR using specific primer for vp1 capsid gene designed by Oligo 7 software. Fisher's exact test was used for statistical analyses. Using MEGA 6 software the sequences were aligned using Clustal W tool and phylogenetic trees were constructed by neighbor joining method. Thirty one positive samples were sequenced. Genotypes 1, 3 and 4 of the virus were detected for the first time in Iran. For the first time genotype 3 was reported as the dominant genotype in Iran. For the first time in the world, genotype 4 was detected in rheumatoid arthritis patients. This article is protected by copyright. All rights reserved.
The availability of a growing number of immunomodulatory medications over the past few years has been associated with various JC virus (JCV)-associated brain syndromes in patients with autoimmune diseases, including multiple sclerosis, Crohn's disease, and psoriasis that had not been previously recognized as predisposing factors for progressive multifocal leukoencephalopathy. This review covers the three novel syndromes discovered in the last decade that are caused by JCV infection of neurons and meningeal cells.
For more than 30 years, JCV was thought to exclusively infect oligodendrocytes and astrocytes in the white matter of the brain of immunosuppressed individuals. We now recognize that JCV-infected glial cells are frequently located at the gray-white matter junction or exclusively within the gray matter causing demyelination in the cortex. Mutations in JCV can trigger a change in tropism leading to involvement of other cell types, such as neurons and meningeal cells, causing clinically distinct entities. These new features of JCV infection provide challenges for clinicians taking care of affected patients and investigators studying the biology of this polyomavirus, its pathogenesis, and tropism.
We hope that increasing awareness of these syndromes will lead to early diagnosis, and pave the way for new avenues of research to better understand all aspects of JCV pathogenesis and develop efficient therapies for our patients. However, we need to remain vigilant and open to the possibility that additional JC variants or yet unknown polyomaviruses may also be associated with neurological diseases.
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 6 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 vs. benign: P < 0.01; CPML vs. asymptomatic: P < 0.05; HIV-1 negative vs. benign: P < 0.01). Organization of the JCV transcriptional control region (TCR) showed unusual archetype structures in two long-term survival patients; the NF1 sequence was found most commonly, whereas the Sp1 binding site was the most common for both CPML patients and HIV-1 negative patients. Our results suggest that the JCV load in the CSF and the organization of the TCR should be considered as indicators of PML clinical outcome.
Progressive multifocal leukoencephalopathy (PML) is a severe neurological disorder due to JC virus (JCV) infection. Pre-diagnostic biological markers and risk factors for PML are not well understood. We conducted a case-control study nested within the Multicenter AIDS Cohort Study to examine the association between JCV viruria and viremia and serum antibody to JCV capsids, in relation to subsequent PML diagnoses, 5 months to 12 years later. Other demographic and immunologic factors were also examined. The study population included 28 incident cases of PML, 26 matched HIV-positive controls, and 50 HIV-negative controls. Prevalence of JCV viruria was 37% in cases, 42% in HIV-positive controls, and 28% in HIV-negative controls (P = 0.43). Among persons with JCV viruria, persistent viruria was more common in cases (89%) than in HIV-positive controls (33%) (P = 0.02). Presence of JCV viruria was not related to the time to PML diagnosis (OR: 1.03, 95% CI: 0.8-1.4); however, the urinary concentration of JCV DNA increased with proximity to the date of PML diagnosis in cases. JCV seropositivity did not differ between cases or controls (P = 0.42). Four cases tested JCV seronegative, including one case only 5 months prior to diagnosis with PML. JCV DNA was detected in the serum of one HIV-positive control. Smoking was the only demographic variable analyzed associated with an increased risk for PML (MOR: 9.0, 95% CI: 1.2-394.5). The results suggest that persistent JCV viruria and increasing urinary concentration of JCV DNA may be predictive of PML for some patients.
The human polyomaviruses, BK virus and JC virus, have long been associated with serious diseases including polyomavirus nephropathy and progressive multifocal leukoencephalopathy. Both viruses establish ubiquitous, persistent infections in healthy individuals. Reactivation can occur when the immune system is impaired, leading to disease progression. Recently, the human polyomavirus family has expanded with the identification of three new viruses (KI, WU and Merkel cell polyomavirus), all of which may prove to be involved in human disease. This review describes the general aspects of human polyomavirus infections and pathogenicity. Current topics of investigation and future directions in the field are also discussed.