Publications

functional role of bk virus tumor antigens in transformation.	we have examined the role of the human papovavirus bk virus (bkv) tumor (t) antigen(s) in the maintenance of transformation and have identified the domain of t antigen essential for transformation. bkv-transformed bhk 21 and nih 3t3 cells expressing antisense t-antigen rna lose their ability to grow in soft agar, indicating the need for the continued expression of t antigen for the maintenance of the transformed phenotype. experiments using translation termination linker insertion and deletion m ...	1988	2846874
antibody-mediated enhancement of bk virus infection in human monocytes and a human macrophage-like cell line.	we have monitored bk virus (bkv) antigen expression and multiplication in human monocytes and in a human macrophage (m luminal diameter)-like cell line (u937) in the presence or absence of dilution series of human or rabbit anti-bkv antisera. after infection with bkv alone, restricted expression (structural antigens and t-antigen) and multiplication was recorded in monocytes from some donors, while in u937 cells and monocytes from other donors, no signs of viral activity were detected. monocyte ...	1988	2835425
expression of the control elements of bk and sv40 viruses in human cells exhibiting different transformed phenotypes.	transformation of primary human embryonic kidney (hek) cells as selected by either focus assay or growth in soft agar after their transfection with bk virus (bkv) dna alone or bkv dna plus the activated form of human ha-ras oncogene has been previously reported (a. pater and m. m. pater, j. virol. 58, 680-683 (1986]. in order to examine the expression of the regulatory elements of papovaviruses in each of the transformed phenotypes, chloramphenical acetyltransferase (cat) plasmids under the cont ...	1988	2833026
inhibition of bk virus haemagglutination by gangliosides.	the effect of gangliosides extracted from human group o rh+ erythrocytes on haemagglutination by bk virus was investigated. experiments were performed on both ganglioside mixtures and isolated fractions separated by column chromatography and characterized by thin-layer chromatography. these results were compared with those obtained with standard preparations of gangliosides, and the inhibiting activity was shown to be confined mainly to gangliosides with a rf lower than gm1. it was also observed ...	1987	3029311
structure and function of the transcriptional control region of nonpassaged bk virus.	we compared the nucleotide sequence in the transcriptional control region of bk virus isolates cloned directly from human urine (bk-ww) with that of prototype bk virus. bk-ww was found to have a 63-base-pair insertion and only one of the 68-base-pair enhancer repeat elements. in transient expression assays, bk-ww enhancer showed approximately one-half the activity given by the prototype enhancer.	1987	3033304
transcriptional trans-activating function of hepatitis b virus.	the ability of hepatitis b virus (hbv) to stimulate the expression of a cellular gene was investigated by using a transient-expression system. a plasmid in which the expression of the bacterial chloramphenicol acetyltransferase (cat) gene had been placed under the control of the dna sequences that regulate the expression of the human beta-interferon gene was constructed. in vero cells, cotransfection of the 2.7-kilobase bglii dna fragment of hbv together with the test plasmid containing the cat ...	1987	2822953
analysis of the early regulatory region of the human papovavirus bk.	bkv is a human papovavirus which latently infects a majority of the world population and whose dna has been found in human tumor tissue. along with simian virus 40 (sv40) and jcv, it is one of several highly homologous polyomaviruses which display distinct host ranges, tissue tropisms, and transformation potentials. determination of these properties is thought to reside, in part, in the noncoding regulatory region of these viruses. we have studied the regulation of gene expression by the early p ...	1987	3033888
the early enhancer-promoter of bkv and host range for transformation.	the early genes of the human papovavirus bkv and simian virus 40 (sv40) show a different host range for transformation. the early region of sv40 efficiently transforms human fibroblast cells, whereas the early region of bkv does not. interchanging noncoding enhancer-promoter sequences around the origin of replication between bkv and sv40 showed that the early enhancer-promoter sequences of bkv and sv40 could substitute for each other, as far as the induction of expression of tumor antigens and m ...	1987	3038777
induction of malignant subcutaneous sarcomas in hamsters by a recombinant dna containing bk virus early region and the activated human c-harvey-ras oncogene.	malignant undifferentiated sarcomas were induced in 11 of 15 (73.3%) newborn syrian hamsters by s.c. inoculation of a recombinant dna (pbk/c-rasa) containing bk virus (bkv) early region gene and the activated human c-harvey-ras(c-ha-ras) oncogene derived from t24 bladder carcinoma. the two genes inoculated independently as well as a recombinant dna of bkv early region gene and normal human c-ha-ras proto-oncogene were not tumorigenic. tumor-derived cell lines propagated in culture were immortali ...	1987	2824040
use of hybridot assay to screen for bk and jc polyomaviruses in non-immunosuppressed patients.	urine samples from 50 patients attending a genitourinary outpatient clinic and from 13 renal allograft recipients were investigated for evidence of infection with human bk and jc polyomaviruses using cytology and a new dna hybridot assay. forty four per cent of samples from the renal allograft recipients were positive by cytology and 75% by dna hybridisation, indicating that hybridot assay is more sensitive than cytological screening. bk and jc viral dna was found in 20% of the patients attendin ...	1987	3040812
neutralization test for bk virus: plaque reduction detected by immunoperoxidase staining.	we developed an immunoperoxidase staining test to detect structural antigens of bk virus (bkv) in vero cell cultures. this test was used to examine the neutralizing activity of human and immunized animal sera. it was shown that sera positive for bkv antibodies measured by hemagglutination inhibition test and enzyme-linked immunosorbent assay (elisa) were able to prevent expression of bkv structural antigens in cell cultures. the correlation between titers in the hemagglutination inhibition test, ...	1986	3016170
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 we ...	1986	2430282
trans-activation of the human immunodeficiency virus long terminal repeat sequence by dna viruses.	to investigate whether dna viruses can augment gene expression of the human immunodeficiency virus (hiv), cotransfection experiments were carried out in which a recombinant plasmid containing the hiv long terminal repeat (ltr) linked to the chloramphenicol acetyltransferase (cat) gene was transfected into cultured cells along with plasmids containing dna from various distinct classes of dna viruses. molecular clones containing jc virus, bk virus, lymphotropic papovavirus, bovine papilloma virus, ...	1986	2432602
xrep, a plasmid-stimulating x chromosomal sequence bearing similarities to the bk virus replication origin and viral enhancers.	the human x chromosome-linked fragment, "xrep," was sequenced because it exerts a positive effect on plasmid growth in both e. coli and saccharomyces cerevisiae. the sequence revealed three features similar to the human bk virus replication origin: xrep has a true palindrome, cctcc(t)3cctcc, which is similar to "true" palindrome-like sequences found at the replication origins of polyoma [cctc(t/c)10ctcc], bk [cctc(a/g)8cctcc] and sv40 [cctcc(a)6gcctcc] viruses. twenty nucleotides away from the t ...	1986	3025813
transforming potential of dna of the human plc/prf/5 hepatoma cell line.	dna of the human plc/prf/5 hepatoma cell line can induce the appearance of colonies on soft agar after transfection of bk-bk cells (balb/c mouse kidney cells partially transformed by bk virus). blot hybridization analyses indicate that the transformants contained the hepatitis b virus dna sequence. this sequence disappeared during serial passage of transformants. the amplification and rearrangement of the integrated bk virus genome appears to be specifically associated with transformation.	1986	3038774
simian agent 12 is a bk virus-like papovavirus which replicates in monkey cells.	we have begun to characterize the genomic structure and replication of the baboon papovavirus simian agent 12 (sa12). we have defined a wild-type clone of sa12 (sa12 wt100) by plaque purification from a heterogeneous stock. the functional map of sa12 wt100 can be aligned with those of the other primate papovaviruses by assigning one of the two ecori sites as 0/1.0 map units. the origin of bidirectional viral dna replication maps near 0.67 map units, consistent with the limits of sequences homolo ...	1985	2985810
cell-mediated immune responses to bk virus in normal individuals.	a lymphoproliferative assay was developed to study cell-mediated immunity (cmi) to bk virus (bkv), a human papovavirus, in healthy volunteer subjects. responses to ultraviolet-inactivated antigen prepared from bkv-infected fibroblasts were compared to those elicited against a mock antigen preparation and an unrelated control antigen (tetanus toxoid, tet). cmi to bkv and tet were contrasted with humoral immunity as measured by enzyme-linked immunosorbent assay (elisa). specificity of the assay wa ...	1985	2999323
detection of bk virus igm antibodies by two enzyme-linked immunosorbent assays (elisa) and a hemagglutination inhibition method.	we have used an antigen solid-phase enzyme-linked immunosorbent assay (sp-elisa) and an igm antibody capture elisa (macelisa) for detecting igm antibodies to human polyomavirus bk (bkv). these tests were compared with the standard hemagglutination inhibition test (hai) of igm serum fractions following sucrose density gradient fractionation. the sp- and macelisa were not influenced by concomitant bkv-igg, but high levels of both bkv-igg and rheumatoid factor could cause false positive results by ...	1985	2997386
direct detection of the human papovavirus bk in urine of bone marrow transplant recipients: comparison of dna hybridization with elisa.	urine specimens from bone marrow transplant (bmt) recipients and from controls were directly tested for bk virus (bkv) dna sequences by dot hybridization and for bkv antigen by a double-antibody indirect elisa. a total of 158 specimens from 55 bmt patients (57 collected prior to or at the time of transplantation and 101 in the posttransplant period) and single urines from 125 control subjects were examined by both methods. a molecularly cloned, 32p-labelled bkv probe was hybridized with urine se ...	1985	2995566
oncogenic activity of the bk type of human papova virus in inbred rat strains.	the oncogenicity of the human polyomavirus bk (bkv) was tested in newborn inbred rats. it was found that the tumor rate was negatively correlated with the levels of t antibody 3 months after inoculation and the frequency of animals with detectable t antibodies 1.5 months after inoculation. by contrast, no influence of viral hi titers on the tumor rates was found. thymectomy of animals resulted in most experiments in increased tumor rates. inoculation with bkv of animals later than 24 hours after ...	1984	6331349
prospective study of the human polyomaviruses bk and jc and cytomegalovirus in renal transplant recipients.	forty eight renal transplant recipients were investigated prospectively for evidence of infection with the polyomaviruses bk and jc and cytomegalovirus. an active polyomavirus infection was shown in 31 patients (65%) and cytomegalovirus in 30 (62.5%). half of the bk and jc virus infections occurred within the first three months after transplantation compared with 93% of the cytomegalovirus infections. very late polyomavirus infections two or more years after the transplant were also shown. cytol ...	1984	6327777
thymidine kinase of herpes virus as a vehicle for the isolation and characterization of unknown mammalian promoters and enhancers.	we have previously reported that the promoter of the thymidine kinase (tk) gene of herpes virus (hsv) can be replaced with the early promoter of sv40. in the present study we report the construction of a tk- plasmid (tk-pml-bglii) in which the tk promoter has been removed and a new bglii site has been regenerated for the insertion of exogenous promoters in front of this nonexpressed gene. we have tested the feasibility of using this plasmid for the isolation of unknown promoters by inserting dna ...	1984	6330263
bk virus-plasmid expression vector that persists episomally in human cells and shuttles into escherichia coli.	we describe a novel expression vector, pbk tk-1, that persists episomally in human cells that can be shuttled into bacteria. this vector includes sequences from bk virus (bkv), the thymidine kinase (tk) gene of herpes simplex virus type 1, and plasmid pml-1. tk+-transformed hela and 143 b cells contained predominantly full-length episomes. there were typically 20 to 40 (hela) and 75 to 120 143 b vector copies per cell, although some 143 b transformants contained hundreds. low-molecular-weight dn ...	1984	6092918
monoclonal antibodies against simian virus 40 nuclear large t tumour antigen: epitope mapping, papova virus cross-reaction and cell surface staining.	thirty six cloned hybridomas have been isolated which produce monoclonal antibodies directed against simian virus 40 (sv40) large t tumour antigen. they have been shown to recognize at least six different epitopes along the t antigen polypeptide according to their reaction with the various truncated forms of t antigen expressed by adenovirus-sv 40 hybrid viruses. sixteen antibodies cross-react with cells infected by the closely related human bk virus. only two antibodies, pab1604 and pab1614, di ...	1984	6204863
survey of human polyomavirus (jcv, bkv) infections in 139 patients with lung cancer, breast cancer, melanoma, or lymphoma.	in 139 patients with breast or lung carcinoma, malignant melanoma, and hodgkin's or non-hodgkin's lymphoma, jc and bk virus serology (hemagglutination inhibition) and urinary polyomavirus excretion (cytology and immunofluorescence microscopy) were studied. overall, 18 of 70 patients with paired sera (26%) had titer increases against jc or bk virus, and 11 of 114 patients (10%) had evidence for urinary excretion. the infection rate was highest in patients with hodgkin's or non-hodgkin's lymphoma ...	1983	6304768
strain differences and some serological observations on several isolates of human polyomaviruses.	six new strains of bk polyomavirus are described and compared by serological reactions and restriction endonuclease digest patterns of their dna to bkv (prototype) and bkv (gs). one strain (pg) had a restriction endonuclease pattern similar to bkv (prototype) but with two ecori cleavage sites. four strains were similar to bkv (gs) and one strain (sb) appeared to be a variant of bkv, having a smaller defective genome. two mixed polyomavirus infections have been identified and a new human polyomav ...	1983	6304748
detection of human papovaviruses bkv and jcv in urines by elisa.	a double-antibody indirect elisa using a chromogenic substrate and a single-antibody sandwich direct elisa using chromogenic and fluorogenic substrates were developed for the detection of the human papovaviruses bkv and jcv. all three assays were comparable in their sensitivity. bkv was detected in urine from 12 of 63 (19%) highly immunocompromised patients and jcv in urine from 4 of 31 (12.9%) patients by the indirect method.	1983	6304754
persistence of dna sequences of bk virus and jc virus in normal human tissues and in diseased tissues.	available evidence suggests that bk virus (bkv) and jc virus (jcv) persist in the kidneys of healthy individuals after primary infection and may reactivate when the host's immune response is impaired. data supporting this hypothesis are presented. a previous study had shown bkv to be present in the kidneys of eight (57%) of 14 subjects. in the present study, which extended the investigation to a total of 30 subjects, bkv dna was found in the renal tissues of 10 (33%) subjects, and jcv dna was fo ...	1983	6302172
bk viral enhancer element and a human cellular homolog.	comparison of two closely related primate papovaviruses, simian virus 40 (sv40) and human bk virus (bkv), reveals that the only region of extensive divergence, the tandem sequences adjacent to the origins of dna replication, is responsible in sv40 for enhancing early gene expression. this study demonstrates a similar enhancer function for the analogous repeated region in bkv. the dissimilarity in sequence of the bkv and sv40 enhancer elements suggests that they may have been acquired since sv40 ...	1983	6314501
multiple origins of the complementary defective genomes of rf and origin proximal sequences of gs, two human papovavirus isolates.	it has previously been shown that the genome of rf virus, a variant of the human papovavirus, bk, consists of two dna species, one (r1a) with a deletion corresponding to the early and the other (r2) with a deletion corresponding to the late region of bkv (a. pater, m.m. pater, and g. di mayorca (1980). j. virol. 36, 480-487; a. pater, m. m. pater, r. m. dougherty, and g. di mayorca (1981a). virology 113, 86-94). in this report transfection experiments are used to show that these dna species are ...	1983	6689230
high-titer sv40 replication in human fibroblast cell lines derived from patients with wiskott-aldrich syndrome.	human fibroblast cell lines established from skin biopsies of patients with wiskott-aldrich syndrome (was), a sex-linked immunodeficiency disorder, were found to have unusually high sensitivity to sv40 infection. when examined by immunofluorescence, two of the cell lines showed almost 100% positive staining for tumor and viral antigens 4 days after infection, while the third cell line showed 75% positive cells for both antigens. marked cytopathic changes were seen in infected cultures and viral ...	1983	6312684
[antibody movement against bk and herpes viruses and cytomegalovirus in kidney transplants].		1982	6320705
susceptibility of balb/cgndu mice to transplantable tumors, in vitro transformed cells, bk and sv40 viruses, and chemical carcinogens.	various oncogenic agents were employed in tumor susceptibility studies of an inbred subline of balb/cgn mice, balb/cgndu, which carries a mutant gene that results in spontaneous thymic involution in homozygous recessive individuals. of 18 transplantable tumors, 3 in vitro transformed cell lines, 2 oncogenic papovaviruses and 3 chemical carcinogens evaluated, only the harding-passey amelanotic melanoma produced tumors in 100% of the normal adult mice injected. the s180 pleomorphic sarcoma produce ...	1982	6283450
tumorigenicity of human bk papovavirus plaque isolates, wild-type and plaque morphology mutant, in hamsters.	the polyoncogenic prototype human papovavirus bkv (gardner's strain) produced clear, small and large plaques. two small-plaque isolates (wt-500 and wt-502), as well as a large-plaque-forming isolate (wt-501), induced frequent brain tumors and occasional osteosarcomas (but no insulinomas) in hamsters. the large-plaque former (wt 501) was more tumorigenic than the two small-plaque mutant (pm-525), which had been rescued from hamster tumor cell lines and have small deletion near the origin of dna r ...	1982	6284657
papovavirus-related rna sequences in human neurogenic tumours.	thirty-two human brain tumours were investigated for the presence of papovavirus-related rna sequences. radiolabelled viral dnas isolated from sv40, bkv, hdv, and bpv were hybridized in-situ on to tumour kryostat sections under conditions that detect complementary rna. sv40-related rna was detectable in 34% of all tumours tested but was not found in normal human brain tissue. sv40-positive tumours included 1/1 angiofibroma, 1/4 astrocytomas, 2/4 metastatic brain tumours, 1/1 melanoma, 3/7 mening ...	1982	6278814
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 ...	1982	6300615
new properties of simian virus 40 large t antigen.	an 8,000-molecular-weight (8k) t antigen was found in all cells transformed by simian virus 40. the 8k t antigen was weakly labeled in vivo with [35s]methionine or 32pi. a deletion in the human papovavirus bk genome, in the region coding for the carboxy-terminal end of the large t antigen, reduced the size of the 8k t antigen. the last 80 amino acids of the large t antigen include the sequence asp-asp-asp-asp unique to the activation peptide of trypsinogen. large t antigen bound diisopropyl fluo ...	1982	14582188
organization of viral genome in a t antigen-negative hamster tumor induced by human papovavirus bk.	we analyzed by blot hybridization the state and structure of the viral dna in an exceptional bk virus-induced hamster tumor (choroid plexus papilloma vn-324) that contains about one copy of the bk virus genome per cell, but no intranuclear t antigen as assayed by indirect immunofluorescence. the bk viral dna was found to be integrated into cellular dna at a site in the middle of the early region of the viral genome (between 0.32 and 0.41 map units). the structure of the inserted viral dna shows ...	1981	6264127
rapid detection and identification of jc virus and bk virus in human urine by using immunofluorescence microscopy.	an indirect immunofluorescence method was developed and used to detect urinary excretion of abnormal transitional cells infected with jc virus (jcv) or bk virus (bkv). this method was compared with urinary cytology, electron microscopy, viral culture, and viral serology in groups of immunosuppressed renal transplant recipients and normal controls. the indirect immunofluorescence method detected and identified jcv excretion in four persons, bkv excretion in one person, and both jcv and bkv excret ...	1980	6244330
dna sequence of human papovavirus bk.		1980	6244496
a prospective study of human polyomavirus infection in pregnancy.	urine samples from 1,235 pregnant women were examined by light microscopy for cytologic evidence of virus infection. smears of urine sediment from 40 women (3.2%) were observed to contain inclusion-bearing cells; polyomavirus infection was confirmed by virologic methods in 24 (60%). a polyomavirus was isolated from 12 women. five isolates were identified as jc virus and one as bk virus. another isolate designated as virus appeared to be unique. serologic studies on the 40 women were consistent w ...	1980	6249869
presence of viral dna sequences in hamster tumors induced by bk virus, a human papovavirus.	dna prepared from cell lines and transplanted tumors originating from five representative types of bkv-induced hamster tumors was examined for the presence of the bkv genome by analyzing dna/dna reassociation kinetics. bkv dna sequences were detected in all cases. there were only a few (1--4) copies of bkv dna per cell in one osteosarcoma and two ventricular tumors (one choroid plexus papilloma and one ependymoma), but there were multiple (up to 150) copies in one osteosarcoma, one ventricular t ...	1980	6261096
immunologic relatedness of papillomaviruses from different species.	an antiserum prepared by immunization of a rabbit with sodium dodecyl sulfate-disrupted virions from a pool of plantar warts was cross-reactive with virus-positive papillomas of other animal species by both indirect immunofluorescence tests on frozen sections of wart tissues and peroxidase-antiperoxidase tests of sections of formalin-fixed tissues. the antiserum stained plantar warts, common warts, and skin lesions of epidermodysplasia verruciformis, all from humans; bovine fibropapilloma, exper ...	1980	6153407
comparative study of papovavirus dna: bkv(mm), bkv(wt) and sv40.	extensive physical mapping revealed that approximately 90% of the genomes of bkv(prototype, wt) and bkv (mm strain) are identical or closely related. nucleotide sequences of the non-homologous regions and a large portion of the homologous regions have been determined for both genomes. the coding sequence of small t antigen of bkv(mm) is 216 nucleotides shorter than that of bkv(wt), even though no differences in biological function of the t antigen was observed. both genomes contain three similar ...	1979	228246
somatic cell hybrids producing antibodies specific for the tumor antigen of simian virus 40.	we have produced somatic cell hybrids between mouse myeloma cells deficient in hypoxanthine phosphoribosyltransferase imp: pyrophosphate phosphoribosyltransferase; ec 2.4.2.8) and spleen cells derived from mice primed with either syngeneic or allogeneic cells transformed by simian virus 40. such hybrids produced antibodies specific for simian virus 40 tumor (t) antigen. only four of twelve independent hybrid cell cultures produced antibodies against simian virus 40 t antigen that crossreacted wi ...	1978	79181
hemagglutination with simian papovavirus sa12.	simian papovavirus sa12 agglutinated human, guinea pig, and chicken erythrocytes. sa12 hemagglutinin was most effectively released from debris of infected tissue culture cells at an alkaline ph.	1978	29051
nucleotide sequence of the dna replication origin for human papovavirus bkv: sequence and structural homology with sv40.	dna and rna sequencing techniques were used to obtain the sequence surrounding the origin of dna replication for human papovavirus bkv. the structure is characterized by a true palindrome of 17 residues followed by two sets of symmetrical sequences and a stretch of 20 at residues. within the two symmetrical sequences is a segment containing a strong purine bias, 23 of 26 nucleotides. these structures are similar, if not identical, to those found in the region of the sv40 replication, origin. wit ...	1978	203403
human polyomavirus (bk) infection and ureteric stenosis in renal allograft recipients.	human polyomavirus (bk) was detected in two renal allograft recipients as a result of routine examination of papanicolaou-stained smears of urinary sediment in the light microscope. infection with this recently identified virus was confirmed by virus isolation and electron microscopy. the cytological, histological, and ultrastructural changes due to the virus are described, and virus excretion is correlated with the clinical progress of the patients and the pathological findings. the transplant ...	1978	205555
transformation of african green monkey kidney cells with the rf strain of human papovavirus bkv.		1978	206005
ependymomas, malignant tumors of pancreatic islets, and osteosarcomas induced in hamsters by bk virus, a human papovavirus.	bk virus (bkv), a human papovavirus, was inoculated iv into 3-week-old syrian golden hamsters. between 2 1/2 and 9 months after inoculation, 82% of the animals developed tumors. the induced neoplasms were ependymoma, carcinoma of the pancreatic islets, osteosarcoma, adenocarcinoma, angiosarcoma, angioma, lymphoma, and seminoma. hypersecretion of insulin, glucagon, c-peptide, and calcitonin was detected in tumors of pancreatic islets. bkv etiology of tumors was supported by the following evidence ...	1978	211243
effect of the incubation temperature on the multiplication of bk virus, a human papovavirus.		1978	225601
jc virus, a human polyomavirus associated with progressive multifocal leukoencephalopathy: additional biological characteristics and antigenic relationships.	jc virus, a human polyomavirus, failed to grow or produce cytopathic effects in any of a variety of cells tested other than primary human fetal glial (phfg) cells. cells tested included other primary human cells and glial cells from other animals. only a rare cell in inoculated insusceptible human cell cultures produced t or virion antigen. in phfg cell cultures jc virus produced subtle cytopathic effects, and the majority of progeny remained cell associated. only a few cells in the heterogenous ...	1977	191404
elevated expression of t-antigen in skin fibroblasts from individuals with cytogenetic anomalies infected in vitro with simian or human papovaviruses.		1977	193118
high incidence of ependymomas induced by bk virus, a human papovavirus: brief communication.	ependymomas were produced in 44 of 50 syrian golden hamsters and in 9 of 31 outbred swiss mice inoculated intracerebrally with high-titer, purified bk virus (bkv). tumors contained a t-antigen that reacted with bkv-specific t-antibody in immunofluorescence and complement-fixation tests. a proportion of tumor-bearing animals had antibodies to bkv t-antigen in their sera. bkv could be rescued from two tumor cell lines by sendal virus-mediated fusion with vero cells. a low, or lack of, oncogenic ac ...	1977	198571
interspecies-, species- and type-specific t antigenic determinants of human papovaviruses (jc and bk) and of simian virus 40.	immunofluorescence tests, absorption studies and quantitative analysis by a very sensitive 51cr microcomplement fixation (cf) technique were used to define the degree of relatedness between the tumor (t) antigens induced by human papovaviruses, strain jc and bk, with simian virus 40(sv40) and mouse polyoma virus (pyv). antisera against jcv, bkv, sv40 and pyv t were raised in tumor-bearing hamsters. the data obtained indicate that t antigens of jcv, bkv and sv40 possess various subspecificities w ...	1977	72046
new human papovaviruses.		1976	62371
malignant transformation of hamster brain cells in vitro by human papovavirus bk.	human papovavirus bk caused the malignant transformation in vitro of brain cells prepared from newborn hamsters. the transformed cells produced bk virus t antigen and grew as tumors after sc inoculation ito hamsters that developed antibodies to bk virus t antigen. the histopathology of the tumors revealed an undifferentiated glioma.	1976	176404
polynucleotide sequences common to the genomes of simian virus 40 and the human papovaviruses jc and bk.		1976	183358
antibodies to bk virus structural and tumor antigens in human sera from normal persons and from patients with various diseases, including neoplasia.	sera from 1,279 patients with various diseases were examined for the presence of antibodies to bk virus (bkv) capsid antigens. the percentage of positive sera was comparable in all the diseases except rheumatoid arthritis and chronic nephropathies, where a slightly higher prevalence was found. sera from 952 patients with tumors were examined for the presence of antibodies to bkv tumor and capsid antigens in comparison with a matched control group of 501 blood donors. sera from 11 tumor patients ...	1976	184044
[human seroepidemiology polyoma virus bk in umbria].	a serological study on the antibody level against bk virus in healthy population and respiratory patients in umbria was performed. serum samples of 465 healthy people and 155 patients grouped by age, were tested using hai. 47% of all sera was positive. the epidemiological implications are discussed.	1976	191046
induction of papillary ependymomas and insulinomas in the syrian golden hamster by bk virus, a human papovavirus.	newborn hamsters were inoculated intracerebrally with bk virus. between 3 and 6 months after inoculation, they developed papillary ependymoma (8 hamsters, 42%) or functional malignant islet cell tumors of the pancreas (insulinoma, 8 hamsters), or both (1 hamster). both tumors contained an antigen reactive to sv40 t-antibody, suggesting that at least a part of bk virus genomen has been integrated into the tumor cells. no infectious virus was detected in the extract of these tumors.	1976	191323
characterization of human papovavirus bk dna.	the dna of the bk virus (bkv) human papovavirus was found to be heterogeneous, consisting of at least four discrete species of dna. only the largest of these four species, bkv dna (i), which has a molecular weight calculated to be 96% that of simian virus 40 (sv40) dna, was infectious. homogeneous preparations of bkv dna were obtained, however, from virions purified after low multiplicity infections of human embryonic kidney cells. bkv dna (i) was shown to contain a single r-eco ri and four r-hi ...	1975	163342
virion polypeptide composition of the human papovavirus bk: comparison with simian virus 40 and polyoma virus.	the polypeptide composition of labeled bk virus was compared with that of simian virus 40 (sv40) and polyoma virus by co-electrophoresis of disrupted virions in polyacrylamide gels containing approximately 73% of the capsid protein and had a molecular weight of 39,000. it was smaller than vp1 of sv40 and polyoma virus. the other polypeptides of bk virus were similar in molecular weight to those of sv40. a comparison of the proteins of bk virus and sv40 iodinated with chloramine t before and aft ...	1975	163921
sarcoma in a hamster inoculated with bk virus, a human papovavirus.	an undifferentiated sarcoma occurred in 1 of 52 hamsters inoculated when newborn with bk virus (bkv), a simian virus 40 (sv40)-related human papovavirus. it was transplantable and grew in tissue culture. sera of tumor-bearing hamsters were without antibodies reactive to bkv virion antigens in hemagglutination-inhibition and neutralizationtexts, but contained antibodies reactive in immunofluorescence (if) tests to sv40 t antigen in sv40-transformed cells and to antigens in cells acutely infected ...	1975	165302
effect of beta-propiolactone on infectivity and haemagglutinin of the bk virus.	the effect of beta-propiolactone (bpl) on the infectivity and haemagglutinating properties of bk virus was studied. no virus multiplication was observed when vero cell cultures were inoculated with virus treated with 0.1 per cent or higher concentration of bpl. on the other hand, treatment of bk virus with 0.1 per cent or lower concentration of bpl had no apparent effect on viral haemagglutinin. bpl at a concentration of 0.1 per cent could therefore be used to prepare bk virus haemagglutinin whi ...	1975	168727
oncogenic properties of human viruses.		1975	170197
new human papovavirus (b.k.) isolated from urine after renal transplantation.		1971	4104714