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At least 19 recordsLinked to original sources
PubMed1982

Transformation of human embryonic fibroblasts by BK virus, BK virus DNA and a subgenomic BK virus DNA fragment.

Human embryonic fibroblasts (HEF) have been transformed by BK virus (BKV) DNA and by u.v.-inactivated or live BKV alone or in association with methyl-cholanthrene (MTC). The transformed cells produced BKV large T and small t antigens as well as the cellular 53 kdal protein, detected by immunofluorescence and immunoprecipitation. After an initial phase of lysis and virus shedding, virus or its coat protein antigen could not be detected in transformed cells. All human transformed cell lines could be superinfected by BKV or BKV DNA, but their susceptibility to superinfection was 20- to 500-fold lower than normal HEF. BKV could be rescued by fusion of transformed cells with normal HEF or Vero cells and by transfection of normal HEF with total DNA and DNA extracted from the Hirt supernatant of transformed cells. Blot hybridization analysis of DNA from transformed cells showed a considerable amount of free BKV DNA in monomeric and polymeric forms. Integrated BKV DNA was absent in most cell lines but present in only small amounts in BKV-transformed cells treated with MTC. Analysis of free BKV DNA with various restriction endonucleases and by blot hybridization showed that monomeric forms were complete BKV genomes, whereas polymers contained both complete and defective or rearranged BKV DNA. Transformation of HEF was also obtained with a 3.7 kilobase (kb) fragment of the BKV genome, produced by sequential digestion of BKV with the restriction endonucleases HhaI and EcoRI. This fragment extends clockwise on the virus genome from 0 to 72.2 map units and contains the entire early region. Blot hybridization analysis of cells transformed by the HhaI/EcoRI 3.7 kb fragment showed two separate integrations of BKV sequences without free virus DNA.

Antigens, Viral↗
PubMed2005

Prevalence of human polyoma virus (BK virus and JC virus) infection in patients with chronic renal disease.

BACKGROUND: Polyoma virus infection in renal transplant patients is sometimes critical in graft survival. But, to date, polyoma virus infection or reactivation has not been checked before renal transplantation. The prevalence of polyoma viruses (BK virus and JC virus) was investigated in 45 patients with renal disease who were future candidates as renal graft recipients. METHODS: Because these viruses are excreted in urine, the urine of these 45 patients was analyzed by polymerase chain reaction (PCR). The urine of 37 age-matched normal subjects (control group) was also investigated. RESULTS: In the control group, 13.5% of the normal subjects were positive for BK virus and 24.3% were positive for JC virus. In the patients with renal disease, 33.3% were positive for BK virus and 33.3% were positive for JC virus; the prevalence of BK virus infection was significantly higher than that in the normal subjects. Patients with renal disease with corticosteroid therapy revealed an especially high prevalence of BK virus infection (55.6%), indicating the possibility of viral reactivation by corticosteroid therapy. CONCLUSIONS: More attention should be paid to polyoma virus infection in candidates for renal transplantation with a previous therapeutic history of corticosteroid administration.

Adrenal Cortex Hormones↗
PubMed1999

Investigation of leukemia cells from children with common acute lymphoblastic leukemia for genomic sequences of the primate polyomaviruses JC virus, BK virus, and simian virus 40.

BACKGROUND: An infectious etiology for childhood acute lymphoblastic leukemia (ALL) has long been suspected, although the characteristics of the putative childhood ALL-inducing agent(s) remain a mystery. We describe the testing of ALL leukemia cells for the presence of DNA sequences of the polyomavirus family: JC virus, BK virus, and simian virus 40 (SV40). PROCEDURE: Cryopreserved leukemia cells from 25 children between 2 and 5 years of age at the time of diagnosis and classified as having "common" ALL (B-precursor ALL expressing the CD19 and CD10 surface antigens) were tested for the presence of polyomavirus sequences using standard PCR methods. RESULTS: Human beta-globin gene sequences were detected in 22 of 25 leukemia specimens. However, polyomavirus sequences were not detected in any of the 22 specimens with amplifiable DNA. CONCLUSIONS: The inability to detect JC virus, BK virus, and SV40 virus DNA sequences in any of the 22 specimens with amplifiable DNA suggests that that these members of the polyomavirus family are unlikely to be causally associated with most childhood ALL. Published 1999 Wiley-Liss, Inc.

BK Virus↗
PubMed2003

Serum antibodies to JC virus, BK virus, simian virus 40, and the risk of incident adult astrocytic brain tumors.

Genomic sequences of the human polyomaviruses, JC virus (JCV) and BK virus (BKV), and simian virus 40 (SV40) have been reported from several types of human brain tumors, but there have been no population-based seroepidemiologic studies to evaluate the association between polyomavirus infection and brain tumors. We conducted a case-control study, nested within a prospective cohort, to investigate the association between antibodies to JCV, BKV, and SV40, as measured in serum collected 1-22 years before diagnosis and incident primary malignant brain tumors. Brain tumor cases (n = 44) and age-, gender-, and race-matched controls (n = 88) were identified from participants of two specimen banks in Washington County, Maryland. IgG antibodies to the capsid proteins of JCV and BKV were assessed using ELISAs. SV40-neutralizing antibodies were measured using plaque neutralization assays. Similar to the general population, the prevalence of JCV and BKV infection was high in our study population (77 and 85%, respectively). Antibodies to SV40 were less prevalent (11%). The odds ratio for subsequent brain tumor development was 1.46 [95% confidence interval (CI), 0.61-3.5] for JCV, 0.66 for BKV (95% CI, 0.22-1.95), and 1.00 for SV40 (95% CI, 0.30-3.32). Given the high prevalence of JCV and BKV infections and the millions who were potentially exposed to SV40 through contaminated polio vaccines, future studies should attempt to replicate these findings.

Aged↗
PubMed1989

Hybrid genomes of the polyomaviruses JC virus, BK virus, and simian virus 40: identification of sequences important for efficient transformation.

Hybrid viral genomes were used to investigate the influence of specific polyomavirus sequences on the transforming behavior of JC virus (JCV). One set of chimeric DNAs was made by exchanging the regulatory regions between JCV and simian virus 40 (SV40) or JCV and BK virus (BKV). A second set of constructs was produced that expressed hybrid JCV-BKV T proteins under the control of either JCV or BKV regulatory signals. Transformation of Rat 2 cells with the parental and chimeric DNAs indicated that both the JCV regulatory signals and the sequence encoding the amino terminus of T protein contributed to the restricted transforming behavior of this virus. Analysis of the viral proteins in the transformed rat cells indicated that the large T antigens of JCV and BKV were less stable than their SV40 counterpart, that small t protein was produced in JCV transformants, and that the subpopulation of T antigen that forms a stable complex with cellular p53 protein was smaller in JCV-transformed cells than in SV40- or BKV-transformed cells.

Animals↗
PubMed1976

Infectivity, oncogenicity and transforming ability of BK virus and BK virus DNA.

The human papovavirus, BK, appeared weakly oncogenic in newborn hamsters and was able to induce in vitro transformation of rat kidney cells. The infectivity of BK virus DNA was determined by employing the DEAE-dextran method. In human embryonic cells the infectivity was approx. 10(5) p.f.u./mug of DNA. The transforming ability of BK virus in primary rat kidney cells was measured by employing the calcium method and appeared to vary from 1 to 10 foci per mug of DNA.

Animals↗
PubMed1992

BK virus.

BK virus is a human polyoma virus that infects the renal epithelium and remains latent until immunosuppression triggers reactivation. After reactivation, BK virus can be detected in the urine by methods currently available in the clinical laboratory. Correlations can be made between BK viruria and the occurrence of both renal and hepatic pathologies. BK virus is emerging as a significant pathogen in transplant patients. Additionally, the presence of BK virus DNA in primary brain and pancreatic tumors suggests that it may have oncogenic potential. Thus far, attempts to treat BK virus infection have been ineffective, though research has opened new avenues for treatment possibilities. Prevention of BK virus and other latent viral reactivation remains a challenge to viral research.

BK Virus↗
PubMed1980

Human polyomavirus infections with JC virus and BK virus in renal transplant patients.

Infection with the human polyomaviruses JC virus and BK virus was studied in 61 immunosuppressed renal transplant patients. Urine cytologic studies, indirect immunofluorescence microscopy, electron microscopy, and serologic studies were used to assess viral activity. Patients records were abstracted for events associated with polyomavirus infections. Polyomavirus excretion in urine was detected in 12 of 61 patients (20%). Eleven excreted JC virus and nine, BK virus. Fourfold hemagglutination-inhibition antibody titer rises occurred in 25 of 61 patients (41%). The serologic data suggested that most JC virus infections were primary, whereas most BK virus infections resulted from virus reactivation. During this 2-year study, 32 of 61 patients (52%) had evidence of active viral replication. Urinary tract excretion was associated with drug-requiring diabetes mellitus (P = 0.001), arterial occlusive disease (P = 0.03), and ureteral stricture with loss of renal function (P = 0.02). Antibody increases to BK virus were associated with a rising seurum creatinine (P = 0.02) and need for transplant biopsy (P = 0.02). Polyomavirus replication was therefore associated with an increased frequency of transplant related complications.

Adolescent↗
PubMed1982

Prevalence rate and age of acquisition of antibodies against JC virus and BK virus in human sera.

A total of 480 serum samples from donors including 384 children up to 10 years of age were examined by the hemagglutination-inhibition (HI) test for the rates of prevalence and age of acquisition of HI antibodies against JC virus and BK virus. Among 136 serum samples from various age groups, there were five (4%) with no detectable antibodies against BK or JC virus, 75 (55%) with antibodies against both viruses, 41 (30.1%) with antibodies against only BK virus and 26 (19%) with antibodies against only JC virus. The prevalence of antibodies against JC and BK viruses was 70.5% and 80.8%, respectively, and the mean HI titers (4 x 2n,n greater than or equal to 1) were 4.90 and 4.30. About 50% of the children had acquired antibodies against BK virus by 3 years of age and against JC virus by 6 years of age. These results indicate that dual latent infections with both viruses are common, although independent infections with either virus are predominant in the human population.

Adolescent↗
PubMed1986

Early regions of JC virus and BK virus induce distinct and tissue-specific tumors in transgenic mice.

JC virus and BK virus are ubiquitous human viruses that share sequence and structural homology with simian virus 40. To characterize tissue-specific expression of these viruses and to establish model systems for the study of human viral-induced disease, transgenic mice containing early regions of each of the viruses were produced. The viral sequences induced tumors in a distinct and tissue-specific manner that was similar to their tissue tropism in humans. Ten JC virus-containing founder mice were produced, of which 5 survived to maturity. Four of them developed adrenal neuroblastomas, which metastasized to several other tissues. JC virus tumor-antigen RNA was detected at high levels in the tumor tissues and at low levels in the normal tissues of these mice. One of the three BK virus-containing mice was abnormally shaped and died at 2 weeks of age. The other two BK virus-containing mice developed primary hepatocellular carcinomas and renal tumors and died at 8-10 months of age. BK virus tumor-antigen RNA was expressed in tumor tissues of both mice. Since each of the viruses retained the general tissue tropism that it exhibits in humans, these data suggest that transgenic mice harboring human viruses will be useful as animal models for viral-induced diseases.

Animals↗
PubMed1975

Occurrence of BK virus and BK virus-specific antibodies in the urine of patients receiving chemotherapy for malignancy.

Urine specimens from 23 children and 9 adults who were undergoing treatment for malignancy as well as urines from 40 normal individuals were concentrated and examined for evidence of papovavirus infection. Papovavirus particles were detected in 6 of 64 urines examined by electron microscopy. Three of the particle-positive urines induced BK virus-specific immunofluorescence after inoculation of WI38 cells, and three isolations of BK virus were made by inoculation of urines from virus-excreting patients into Vero cells. BK virus-specific hemagglutination-inhibiting and immunofluorescence neutralizing antibodies were found in a majority of urines from adult patients, in about a fifth of pediatric patients, and less often in normal urines. Urines of virus-excreting patients generally had antibodies. In indirect fluorescent antibody tests, BK virus-specific antibodies of the immunoglobulin G class were found in five urine specimens from patients; immunoglobulin A antibodies were not detected in any urine. These data suggest that activation of BK virus is related to immunosuppression and not to transplantation itself and that the occurrence of virus-specific antibodies in urine may be indicative of virus multiplication in the urinary tract.

Adolescent↗
PubMed1980

Integrated and free viral DNA in hamster tumors induced by BK virus.

BK virus (BKV)-induced tumors in hamsters were investigated for the presence of viral DNA by the blot-transfer hybridization technique. Several viral genomes per cell were found in tumor tissues and in their derived cell lines and clones. Most of the detected viral genomes were integrated into the cellular DNA, but some tumors also contained free viral DNA sequences. Integration patterns were different from each other, and many different integration sites were available on the cellular or on the viral DNA or on both. Typical features of integration patterns were found in ependymomas, which were the most frequent (72%) among BKV-induced tumors. Readily detectable viral DNA sequences were only found in neoplastic tissues, but traces of BKV DNA were also present in the apparently normal portion of the brain of an animal that had developed an ependymoma and in the brain (but not in the liver) of another animal 15 days after virus inoculation. A cell line and a single-cell clone derived from a tumor had hybridization patterns considerably simpler that the pattern of the original tumor, lacking several integrated viral genomes and all free viral sequences.

Adenoma, Islet Cell↗
PubMed1994

Complex functional interactions at the early enhancer of the PQ strain of BK virus.

BK virus is a human papovavirus that latently infects a majority of the world's population. There are more than 30 strains of the virus, most of which differ in the structure of the early enhancer region. The enhancer of the progenitor strain, WW, from which the other strains can be derived, consists of four conserved DNA domains, P, Q, R, and S. Rearrangement of the enhancer occurs upon passage in tissue culture and is thought to occur during virus replication. The strain under study, PQ, was selected upon passage of the Gardner strain (PPPQS) in the permissive cell line, Vero. Mutational analysis of the entire enhancer region demonstrates the importance of five cis-acting sequences: DNA sites B, C, and F, which have homology to the NF-1 protein binding sequence; one purine-rich motif designated A; and site D, which is similar to an SP-1 protein binding site. Two sites, B and C, appear to have a negative influence on gene activity. To study the functional interactions in more detail, promoter-enhancer constructions that contain different combinations of the five DNA sites linked to the chloramphenicol acetyltransferase gene were tested for early gene activity. The results reveal that the proteins binding to the enhancer functionally cooperate with each other. The effects of making mutations at the DNA sites are very similar to the effects of using excess enhancer DNA sequences to titrate the proteins that bind to the cis-acting DNA sites (in vivo competition). Moreover, the effects of changing the spacing between the DNA sites also demonstrate that there are cooperative interactions among the proteins that bind to the PQ strain enhancer. DNA sites B, C, and F are clearly protected from DNase I digestion by Vero cell nuclear proteins. In addition, mutation of each DNA site alters its sensitivity to DNase I in the presence of Vero cell proteins. Interestingly, mutation of site B affects protein binding to site B as well as to sites A, C, D, and F. These results suggest that cooperative functional and physical interactions occur at the early enhancer of the PQ strain.

Animals↗
PubMed2005

An N-linked glycoprotein with alpha(2,3)-linked sialic acid is a receptor for BK virus.

BK virus (BKV) is a common human polyomavirus infecting >80% of the population worldwide. Infection with BKV is asymptomatic, but reactivation in renal transplant recipients can lead to polyomavirus-associated nephropathy. In this report, we show that enzymatic removal of alpha(2,3)-linked sialic acid from cells inhibited BKV infection. Reconstitution of asialo cells with alpha(2,3)-specific sialyltransferase restored susceptibility to infection. Inhibition of N-linked glycosylation with tunicamycin reduced infection, but inhibition of O-linked glycosylation did not. An O-linked-specific alpha(2,3)-sialyltransferase was unable to restore infection in asialo cells. Taken together, these data indicate that an N-linked glycoprotein containing alpha(2,3)-linked sialic acid is a critical component of the cellular receptor for BKV.

Animals↗
PubMed2003

Serological cross-reactivities between antibodies to simian virus 40, BK virus, and JC virus assessed by virus-like-particle-based enzyme immunoassays.

Enzyme immunoassays (EIAs) for detection of serum antibodies to simian virus 40 (SV40), BK virus (BKV), and JC virus (JCV) were developed by using virus-like-particles (VLPs) produced in insect cells from recombinant baculoviruses expressing the VP1 protein of the respective virus. Rhesus macaque sera with neutralizing antibodies to SV40 showed a high level of reactivity in the SV40 VLP-based EIA, and these sera also showed lower levels of reactivity in the BKV and JCV VLP-based EIAs. Rhesus macaque sera negative for neutralizing antibodies to SV40 were negative in all three EIAs. Competitive binding assays showed that SV40 VLPs inhibited BKV reactivity. In rhesus macaque sera, high optical density (OD) values for antibodies to SV40 VLPs were correlated with high OD values for antibodies to BKV but not with high OD values for antibodies to JCV VLPs. Human sera with neutralizing antibodies to SV40 were more reactive to SV40 VLPs than human sera without neutralizing antibodies to SV40. The greater SV40 reactivities of human sera were correlated with greater reactivities to BKV VLPs but not JCV VLPs. These data suggest that cross-reactivity with BKV antibodies may account for part of the low-level SV40 reactivity seen in human sera. With their greater versatility and their suitability for large-scale testing, the VLP-based EIAs for SV40, BKV, and JCV are likely to contribute to a better understanding of the biology of these viruses.

Animals↗
PubMed2000

Comparison of antibody titers determined by hemagglutination inhibition and enzyme immunoassay for JC virus and BK virus.

A comparison of antibody titers to JC virus (JCV) or BK virus (BKV) was made by hemagglutination inhibition (HI) and enzyme immunoassay (EIA) with 114 human plasma samples. Antibody titers to JCV or BKV determined by HI were lower than those determined by EIA. Nevertheless, as HI titers increased so did EIA titers. When antibody data were compared by the Spearman rank correlation test, highly significant correlations were found between HI and EIA titers. Results obtained by plotting EIA antibody titers for JCV against those for BKV generally showed a reciprocal relationship, i.e., samples with high antibody titers to JCV had lower antibody titers to BKV and vice versa. Some samples, however, had antibody titers to both viruses. Of the samples tested, 25.4% (25 of 114) had HI and EIA antibody titers to JCV and BKV which were identical or closely related. This is not the scenario one would expect for cross-reactive epitopes shared by the two viruses, but one suggesting that these samples were from individuals who had experienced infections by both viruses. Adsorption with concentrated JCV or BKV antigen of sera with high antibody titers to both JCV and BKV and testing by JCV and BKV EIA gave results which support this conclusion. Although 52.6% (51 of 97) of the samples from the Japanese population tested had very high antibody titers (>/=40,960) to either JCV or BKV, none of the samples were found by a dot blot immunoassay to have antibodies which cross-reacted with simian virus 40. The results from this study, in agreement with those of others, suggest that humans infected by JCV or BKV produce antibodies to species-specific epitopes on their VP1 capsid protein, which is associated with hemagglutination and cellular binding.

Antibodies, Viral↗
PubMed2005

Genetic analysis of JC virus and BK virus from a patient with progressive multifocal leukoencephalopathy with hyper IgM syndrome.

A case of acute progressive multifocal leukoencephalopathy (PML) with hyper IgM syndrome 1 is reported. Viral DNA and VP1 protein of JC virus (JCV) and BK virus (BKV) were detected by immunohistochemistry, in situ hybridization, semi-nested polymerase chain (PCR) and PCR-restriction enzyme analysis. JCV DNA and VP1 protein were found in the nuclei of oligodendrocytes. The non-coding control region (NCCR) and VP1 region of the JCV genome were sequenced; this revealed a novel rearrangement pattern of the NCCR in the brain tissue. The VP1 regions of brain and urine JCV were identical and of genotype type 2A. The BKV in the urine sample was genotype I. No BKV genome was found in the brain. The novel genomic rearrangement of the JCV NCCR in the brain tissue may have altered JCV pathogenesis to induce PML; the impaired immunity from hyper IgM syndrome 1 may have enabled the rearrangement. The JCV NCCR rearrangement in the brain may have originated from the archetypal form in the urine through deletion and duplication.

Adult↗