Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “parvovirus”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,333 records · Page 74Linked to original sources
PubMed2000

Immunoreactivity against linear epitopes of parvovirus B19 structural proteins. Immunodominance of the amino-terminal half of the unique region of VP1.

Three peptides corresponding to the 2-100 amino acids of VP1 unique sequence (VP1-F1), to the 99-227 amino acids of VP1 unique sequence (VP1-F2) and to the 237-781 amino acids of VP1 protein common to VP2 (VP1-F3 = VP2) were produced by prokaryotic expression. The three peptides, which span the entire VP1 structural protein of parvovirus B19 and also the entire VP2 protein, were used to evaluate the immunoreactivity against linear epitopes of these fragments in a large number of serum samples taken in different clinical situations with regards to B19 infection and in some commercial preparations of aspecific immunoglobulins. The data demonstrated that the specific VP1-F1 fragment, corresponding to the amino-terminal half of the VP1 unique region, is immunodominant and can elicit a long lasting immune response in comparison with VP1-F2 and VP1-F3 = VP2. Data regarding the presence of specific IgG to the three fragments in commercial preparations of immunoglobulins demonstrated that the dominant immune response was also against VP1-F1 linear epitopes while IgG against VP1-F2 and IgG against VP1-F3 = VP2 could be found only in high concentrations of Ig preparations. The reported data can be useful as a basis for the development of a B19 recombinant vaccine.

Adolescent↗
PubMed1996

A case of early intrauterine parvovirus B19 infection.

We present a case of parvovirus B19 infection in the first trimester, confirmed by polymerase chain reaction (PCR) in amniotic fluid and cord blood, that caused myocarditis, severe intrauterine growth retardation, and probably glomerulonephritis. Eventually a small-for-dates neonate was born, without any signs of the infection.

Adult↗
PubMed1996

Analysis of serological surveys using mixture models: application to a survey of parvovirus B19.

A method for the analysis of age stratified antibody prevalence surveys is developed. The age specific distribution of the quantitative results of serological antibody tests is modelled as a mixture of seropositive and seronegative components. This yields maximum likelihood estimates of the prevalence at each age. The method is illustrated using data from a previously reported survey of antibody to parvovirus B19.

Adolescent↗
PubMed2001

Scanning force microscopy study on a single-stranded DNA: the genome of parvovirus B19.

The genome of parvovirus B19 is a 5600-base-long single-stranded DNA molecule with peculiar sequence symmetries. Both complementary forms of this single-stranded DNA are contained in distinct virions and they hybridize intermolecularly to double-stranded DNA if extracted from the capsids with traditional methods, thus losing some of their native structural features. A scanning force microscopy analysis of these double-stranded DNA molecules after thermal denaturation and renaturation gave us the chance to study the possible states that this DNA can assume in both its single-stranded and double-stranded forms. A novel but still poorly reproducible in situ lysis experiment that we have conducted on single virions with the scanning force microscope made it possible to image the totally unpaired state that the single-stranded DNA molecule most likely assumes inside the viral particle. Structural considerations on single molecules offer the opportunity for the formulation of plausible hypotheses on the interaction between the DNA and the viral structural proteins that could prove important for the DNA packaging in the capsid and, possibly, the viral infection mechanisms.

Capsid↗
PubMed1999

The role of parvovirus B19 in the pathogenesis of giant cell arteritis: a preliminary evaluation.

OBJECTIVE: To determine whether parvovirus B19 DNA is more likely to be present in the temporal arteries of patients with giant cell arteritis (GCA) than in the temporal arteries of control subjects. METHODS: We prospectively examined temporal artery biopsy (TAB) tissue from 50 consecutive patients presenting for TAB for the presence of B19 DNA using the polymerase chain reaction (PCR). Clinical and demographic information was obtained from the patients' medical records. A separate PCR analysis of 30 original tissue specimens was conducted at the Centers for Disease Control and Prevention (CDC) using primers directed toward another target sequence in the nonstructural coding area of B19. RESULTS: The 50 patients had an average age of 70.8 years; 27 (54%) were female. Amplicons for human beta-globulin, but not for cytomegalovirus, were produced for all tissue samples. The PCR results for B19 agreed in 29 of 30 samples tested by our institution and by the CDC (97% agreement; kappa = 0.9). A comparison of the B19 DNA analysis and the results of TAB indicated a statistically significant association between histologic evidence of GCA and the presence of B19 DNA in TAB tissue (chi2 = 10.38, P = 0.0013). CONCLUSION: These findings suggest that B19 may play a role in the pathogenesis of GCA.

Aged↗
PubMed1993

Human parvovirus B19 infection in bone marrow transplantation patients.

We report the results of a survey of parvovirus B19 infection carried out with the aim to evaluate the frequency and the role of this infection in bone marrow transplant (BMT) recipients, as it is known that B19 virus can persist in clinical circumstances of immunodeficiency. Fifty-one patients subjected to BMT in the Bone Marrow Transplantation Center of Florence were enrolled in this study. Immunological and virological indications of B19 infection were tested weekly during the stay in hospital. A high rate of seroconversion or B19 antibody rise was observed, but, in absence of B19 IgM or B19 DNA presence, this result seems to be attributable to a passive immunization, rather than to a recent viral infection. In these 51 patients, as well as in 59 others not included in this study, clinical manifestations imputable to B19 infection have never been observed. It is possible that the isolation measures and the intravenous immunoglobulins (IVIG) administration may contribute in preventing B19 infection in the BMT recipients at least until the hospital discharge.

Adult↗
PubMed1996

Bilateral brachial plexus neuritis following parvovirus B19 and cytomegalovirus infection.

A man, 23 years of age, had a typical erythema infectiosum, complicated by a severe bilateral brachial plexus neuritis. Motor function recovered slowly and only partially after 6 months. An infection by human parvovirus B19 was demonstrated, with strongly positive and gradually declining IgM antibodies and viral DNA detectable in serum for more than 3 months. There was also clear evidence of a recent infection by cytomegalovirus. The interaction between these two viruses could be responsible for this rare and severe complication of common infections in this patient.

Adult↗
PubMedDate not supplied

Parvovirus B19 and immune disorders.

Parvovirus B19 (PVB19) is the causative agent of erythema infectiosum and sometimes the infection is correlated with severe haematological complications, or in pregnancy to fetalis hydrops. Moreover some authors suggest an infection involvement in some autoimmune diseases. To this purpose we evaluated seroprevalence for PVB19 in following the autoimmune or dysreactive pathologies: systemic lupus erythematosus (SLE), cryoglobulinemia, idiopathic systemic--ANCA associated vasculitis, rheumatoid arthritis (RA). In the case of LES, 31/42 patients were positive for PVB19 versus 21/42 of blood donors, as controls subjects (73.8% vs. 50%; significant difference for p < 0.05), moreover a significant difference for p < 0.001 was detected comparing mean titre values of IgGs against PVB19 of two groups (UI 1.94 +/- 0.90 vs. 1.24 +/- 0.80). In contrast no significant differences were found in the case of percent seropositivity of cryoglobulinemic subjects (37/57 = 64.9%, the majority of whom were HCV+) in comparison with the control group (50%). However mean units index (UI) was 1.63 +/- 0.81; p = 0.019 versus the control group. Similar result, with regard to the percentage of seropositivity, was found for vasculitis (9/17 = 52.9%). The data reported here can confirm a possible correlation between PVB19 prior infection and LES and also suggest possible implications in the case of cryoglobulinemia. In fact, most of our patients were affected by a nephropathic or systemic form of HCV+ cryoglobulinemia and the presence of other infective cofactors could be suggestive in the evolution of this clinical situation.

Adult↗
PubMed1993

Parvovirus H-1 inhibits growth of short-term tumor-derived but not normal mammary tissue cultures.

Infection with parvovirus H-1 strongly interfered with the proliferation of non-established tissue cultures derived from human breast tumors, but had little effect on the growth of corresponding normal human mammary cells. Even though tumor cells were always more sensitive to the virus than normal tissue from the same patient, appreciable quantitative differences were observed among tumor specimens. With time and sub-cultures, the killing effect of the virus on tumor cells became amplified. The impaired growth of infected tumor cells was due both to cytotoxic and to cytostatic action of H-1 virus and was associated with their greater capacity for virus-DNA amplification as compared with normal cells.

Breast↗
PubMed1995

Growth properties of a human melanoma cell line are altered by adeno-associated parvovirus type 2.

The adeno-associated parvoviruses (AAV) are known for their oncosuppressive activity. This report shows that infection of the human melanoma cell line MKr with AAV-2 leads to chromosomal integration of the viral DNA. The resulting cultures show decrease of saturation density and reduction in their ability to form colonies from single cells and thus to resemble normal cells. After single-cell cloning they may give rise to growth-arrested, terminally differentiating large, multinucleated cells with dendrite-like extensions, large nucleoli and the ability to synthesize melanin pigment. In cultured melanoma cells, melanin synthesis is correlated with cellular senescence, and since senescent cells cease to proliferate and withdraw from the cell cycle, the apparent induction of growth arrest and terminal differentiation in malignant cells by AAV may provide one explanation for the anti-neoplastic activity of these viruses.

DNA, Viral↗
PubMed1992

Laboratory diagnosis of parvovirus B19 infection.

The sensitivity and application of the polymerase chain reaction (PCR) for the diagnosis of parvovirus B19 (B19) infection was investigated by simultaneously assaying a collection of 279 consecutively received samples for presence of anti-B19 IgM and IgG antibodies by Western blot and for B19 DNA by PCR and dot-blot hybridization (dot-blot); samples were sera from patients with suspected B19 infection. PCR and dot-blot detected B19 DNA in 9% (16/179) and 1% (2/179), respectively of Ab-positive samples (IgM+/IgG-, IgM+IgG+, IgM-IgG+), and in 28% (15/54) and 2% (1/54), respectively, of IgM+ samples. PCR also detected B19 DNA in 2% (2/100) of IgM-/IgG- samples, both of which had normal total IgG and IgM levels. PCR is of unique value because it permits diagnosis of B19 infection even in the absence of specific acute phase (IgM) and in the presence or absence of convalescent-phase (IgG) Ab.

Antibodies, Viral↗
PubMed2002

Detection of parvovirus B19 NS1-specific antibodies by ELISA and western blotting employing recombinant NS1 protein as antigen.

Human parvovirus B19 (B19) encodes a number of nonstructural proteins, including the major protein, NS1, and two structural proteins, VP1 and VP2. The use of denatured NS1 in enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) assay has provided an opportunity to study some of the immunologic properties of NS1, but the results have been equivocal and the diagnostic sensitivity poor, probably because of the absence of conformational epitopes. Various viral isolates and baculovirus vectors were employed to produce recombinant B19 NS1 under nondenaturing conditions for the first time. To assess the antigenicity of purified B19 NS1, the reaction patterns of 252 samples were compared by B19 NS1 and VP2 ELISA. In sera from individuals with past infection (VP2 IgG-positive), the use of this new antigen increased significantly the sensitivity of ELISA compared with WB (78% vs. 33%, P = 0.001), contradicting perpetuated claims that B19 NS1 IgG is detected primarily in patients with arthralgia or chronic infection. Previous reports of the absence of NS1 IgG during the initial phase of infection (< 6 weeks) were proved incorrect by the detection of NS1 IgG in 60% of samples from patients recently infected by B19. Including conformational epitopes in the ELISA increases the diagnostic sensitivity, although immunologically, a temporal (years) attenuation of NS1 antibodies appears to take place. This novel diagnostic tool may be useful as a supplement in case of borderline results by VP2 ELISA and for monitoring the efficacy of future capsid-based B19 vaccines.

Animals↗
PubMed2003

Ex vivo cytokine responses against parvovirus B19 antigens in previously infected pregnant women.

Parvovirus B19 infection is a significant cause of fetal death. The aim of this study was to investigate the role of maternal immune status in modulating susceptibility to fetal B19 infection. Peripheral blood was obtained from pregnant women (n = 199) with no clinical evidence of recent B19 infection. Evaluation of ex vivo T cell responses from 149/199 individuals showed significantly higher interferon-gamma levels for seropositive individuals following VP1 (268 +/- 36 versus 103 +/- 19 pg/ml; P = 0.003) and VP2 (242 +/- 42 versus 91 +/- 16 pg/ml; P = 0.01) antigen stimulation. Significantly higher levels of interleukin-2 were also observed in seropositive individuals following both VP1 (P = 0.0003) and VP2 (P = 0.0005) stimulation. The observed Th1 cellular response is lower than that documented previously for non-pregnant individuals and strongly suggests that diminution of the maternal anti-viral immune response may increase susceptibility to fetal B19 infection.

Adolescent↗
PubMed1991

Removal of parvovirus B19 from contaminated factor VIII during fractionation.

A solution of pooled cryo-precipitate for preparing factor VIII (F VIII) by the solvent/detergent method was contaminated experimentally with parvovirus B19-positive plasma to evaluate virus reduction achieved by the final steps of the F VIII production process. Virus reduction was at least 2 logs of the total amount of B19 virus added to the pooled cryo-precipitate. The major amount of B19 virus was detected in the solution used to regenerate the F VIII-selective anion exchange chromatography column. A few viral particles were detected in the final F VIII concentrate before filtration but these were aggregates and were removed by filtration, and in the solution used to regenerate the anion exchange resin. It is not known whether the residual viral DNA present in the final product represents infectious or inactivated particles.

Blood Preservation↗
PubMed1991

Human parvovirus B19 specific IgG, IgA, and IgM antibodies and DNA in serum specimens from persons with erythema infectiosum.

To determine the diagnostic use of different markers of acute parvovirus B19 infection, serum specimens obtained from 128 persons with erythema infectiosum were tested for specific immunoglobulin G (IgG), IgA, and IgM antibodies by capture enzyme immunoassay (EIA) using Chinese hamster ovary (CHO) cell-expressed B19 antigen, and tested for circulating B19 DNA by polymerase chain reaction (PCR). A significant rise in specific IgG and IgA antibodies was detected in 87% and 77%, respectively, of persons from whom acute- and convalescent-phase serum specimens were available. Specific IgA antibodies were detected in single serum specimens from 90% of cases and were present in 22 (18%) of 120 persons from a control group without a history of recent exposure to B19. Specific IgM antibodies were detected in 97% of cases and one person (1%) from the control group. B19 DNA was detected in 94% of cases and was absent in 20 persons from the control group positive for both IgG and IgA antibodies. Serum specimens obtained between 4 and 6 months after onset of illness from six additional persons were also tested. All had specific IgG antibodies, four (67%) had IgA, five (83%) had IgM, and none had detectable B19 DNA. Our data indicate that 1) specific IgA antibodies are too persistent to be a useful indicator of recent B19 infection; 2) specific IgM antibodies are the most sensitive indicator of acute B19 infection in immunologically normal persons but can persist up to 6 months; and 3) B19 DNA can often be detected up to 2 months after onset of illness even in immunologically normal hosts and might be a useful adjunct test for diagnosis of acute B19 infection.

Adolescent↗
PubMed1993

Partial nucleotide sequencing and characterization of human parvovirus B19 genome DNAs from damaged human fetuses and from patients with leukemia.

While human parvovirus B19 is associated with fetal damage and chronic suppression of bone marrow in patients with leukemia, much less is known of the genomic characteristics of B19 isolated from damaged human fetuses and leukemia patients. B19 genome DNAs from human fetal organs and fluids and sera from leukemia patients were amplified by the polymerase chain reaction. The nucleotide sequences of amplified products in the region between nucleotide (nt) 3141 and nt3411 were determined following molecular cloning in M13 phage. The genome types of B19 from the fetuses and leukemia patients were similar to the types from patients with aplastic crisis and an asymptomatic individual. Wide diversity of the nucleotide sequence, i.e., six or more (6-11) substitutions, were evident in ten M13 phage clones of each DNA source from fetal materials, while substitutions in sera from patients with leukemia and aplastic crisis and of an asymptomatic individual numbered four or fewer (0-4). This wide diversity of B19 viruses in the fetus, revealed after many rounds of DNA replication, probably depends on a persistent state of infection.

Adolescent↗
PubMed1993

Human parvovirus B19 infections: routine diagnosis by a new nested polymerase chain reaction assay.

A nested primer PCR assay was developed to detect human parvovirus B19 in various clinical specimens in a routine diagnostic laboratory. Under optimized conditions the highly specific assay had a sensitivity of less than 10 genome units. For practical reasons, however, this sensitivity was adjusted to 10-100 virus genomes in diagnostic applications. Using clinical specimens from 200 patients with suspected B19 infection, nested PCR was shown to have important diagnostic advantages over the detection of B19 specific antibodies. The data suggest that on the basis of serological data as obtained with currently available test systems a considerable proportion of B19 infections would be misdiagnosed. Examples for the usefulness of the PCR assay in routine diagnosis are given.

Adolescent↗
PubMed1994

Case report: detection of parvovirus B19 in a skin biopsy of a patient with erythema infectiosum.

We report the findings on a skin biopsy taken from a child acutely infected with parvovirus B19 showing the typical exanthematous rash. By indirect immunofluorescence with a monoclonal antibody to B19, viral capsid proteins were detected in epidermal cells localized mainly in the stratum basale. Additionally, B19 DNA was detected in epidermal cells of the stratum basale by in situ hybridization using a Dig-labelled B19 DNA probe. The detection of viral capsid proteins and viral DNA suggests the presence of complete viral particles. It is therefore concluded that B19 plays a direct role in the formation of the exanthematous rash in erythema infection.

Biopsy↗