[Reactivation of parvovirus B19 infection in an HIV-infected woman]. / Réactivation d'une infection à parvovirus B19 chez une patiente infectée par le VIH.

INTRODUCTION: Infection by human parvovirus B19 (erythrovirus B19) is common and usually asymptomatic during childhood conferring lasting protection against a new infection. Parvovirus B19 infection may cause erythema infectiosum (5th disease) and aplastic crisis. Secondary symptomatic parvovirus B19 infection in the same patient is rare and its physiopathology is not always clear. CASE REPORT: A 48-year-old HIV-infected female patient presented within 5 years two acute episodes of parvovirus B19 infection although her CD4 cells count was above 500/mm(3). Absence of specific antibodies production after the first episode and persisting parvovirus viremia suggested viral reactivation rather than re-infection. During the second episode, specific antibodies were produced. CONCLUSION: Similarly to most DNA viruses, parvovirus B19 reactivation is possible in HIV-infected patients while effectively treated by antiretroviral therapy.

Chinese goose (Anser cygnoides) CD8a: cloning, tissue distribution and immunobiological in splenic mononuclear cells.

CD8 molecule is a cell membrane glycoprotein, which plays an important role in cell-mediated immunity. Here, we identified Chinese goose CD8α (goCD8α) gene for the first time. The full-length cDNA of goCD8α is 1459bp in length and contains a 711bp open reading frame. Phylogenetic analysis shows that the waterfowl CD8α formed a monophyletic group. Semi-quantitative RT-PCR analysis showed that transcripts of goCD8α mRNA were high in the immune-related organs and mucosal immune system in gosling, and high in thymus and spleen comparing to other immune-related tissues in goose. The obvious increase of CD8α expression was observed in spleen of acute new type gosling viral enteritis virus (NGVEV) infected bird, while the increase of CD8α were observed in the thymus, bursa of fabricius, and cecum of chronic infected bird. The CD8α mRNA transcription level in spleen mononuclear cells was significantly up-regulated when stimulated by phytohemagglutinin, but not by lipopolysaccharide in vitro.

Humoral and cellular immune responses in adult geese induced by an inactivated vaccine against new type gosling viral enteritis virus.

To assess the immunogenicity of an inactivated new type gosling viral enteritis virus (NGVEV) vaccine, we investigated 3 different doses of the inactivated vaccine and the inactivated vaccine in conjunction with 3 different doses of recombinant goose interleukin-2 (rGoIL-2) adjuvant. A virus concentration of 10(5) 50% embryo infective dose/mL was subcutaneously inoculated into adult geese divided into 6 groups. The dynamic changes of the humoral and cellular immunity responses elicited by the vaccines in the adult geese postvaccination (PV) were investigated using ELISA, virus neutralization test, and lymphocyte proliferation assay. The clearance of virus from the intestines of geese (175 d PV) was studied by histopathological examination and indirect immunofluorescence assay after virulent NGVEV challenge. This study showed that the inactivated NGVEV vaccine elicits strong humoral and cellular responses in the vaccinated adult geese. The absorbance values of specific anti-NGVEV antibodies, the neutralization antibody titer, and the lymphocyte proliferation index rapidly increased, peaked at about 28 d PV, progressed to the plateau stage, and then decreased slightly. The rGoIL-2 adjuvant enhanced the immune response, and this adjuvant in conjunction with the inactivated NGVEV vaccine induces a significantly higher specific anti-NGVEV antibody absorbance value, neutralization antibody titer, and lymphocyte proliferation index than the non-adjuvant-inactivated NGVEV vaccine (P < 0.05). The inactivated NGVEV vaccine conferred adequate efficient ability to clear NGVEV in vaccinated geese even in the last phase of the vaccination period (175 d PV). The inactivated NGVEV vaccine (0.5 mL/goose) with 1,000 units of rGoIL-2 adjuvant/goose is the most effective dose, thereby eliciting the strongest humoral and cellular immunity responses and providing the most efficacious clearance of NGVEV in vivo.

[IgM antibody detection in acute viral diseases, 1995-2004: analysis of data collected at a commercial diagnostic laboratory in Japan].

We analyzed data from tests for virus-specific IgM in 376,000 serum specimens sent to a commercial diagnostic laboratory from clinics nationwide between 1995 and 2004. IgM antibodies to measles, rubella, mumps, parvo B19, and varicella-zoster viruses were tested using IgM-capture ELISA kits. Among specimens, 254,000 (68%) had documentation of age, of which 56% were sera from persons<20 and 44%> or = 20 years of age. Monthly or yearly trends in IgM antibody-positive tests in<20 year-old persons were similar to those in pediatric patients per sentinel clinic reported by the National Epidemiological Surveillance of Infectious Diseases (NESID), which collects weekly numbers of patients with designated infectious diseases from 3000 pediatrics clinics nationwide. Patterns of changes in monthly IgM positive tests in both < 20 and > or = 20 y specimens were similar, indicating that infections occur simultaneously in both children and adults. Adult IgM-positive specimens came from internal medicine clinics and from dermatology clinics for measles; from dermatology and obstetrics clinics for rubella and parvo B19; from otolaryngology clinics for mumps; and from dermatology and otolaryngology clinics for varicella-zoster virus. Analysis of large numbers of IgM test results at regular intervals may contribute to understanding of the epidemiology of these viral diseases in Japan.

TLR activation synergizes with Kilham rat virus infection to induce diabetes in BBDR rats.

Virus infection is hypothesized to be an important environmental "trigger" of type 1 diabetes in humans. We used the BBDR rat model to investigate the relationship between viral infection and autoimmune diabetes. BBDR rats are diabetes-free in viral Ab-free housing, but the disease develops in approximately 30% of BBDR rats infected with Kilham rat virus (KRV) through a process that does not involve infection of pancreatic beta cells. Pretreatment with polyinosinic-polycytidylic (poly(I:C)), a ligand of TLR3, acts synergistically to induce diabetes in 100% of KRV-infected rats. The mechanisms by which KRV induces diabetes and TLR3 ligation facilitates this process are not clear. In this study, we demonstrate that activation of the innate immune system plays a crucial role in diabetes induction. We report that multiple TLR agonists synergize with KRV infection to induce diabetes in BBDR rats, as do heat-killed Escherichia coli or Staphylococcus aureus (natural TLR agonists). KRV infection increases serum IL-12 p40 in a strain-specific manner, and increases IL-12 p40, IFN-gamma-inducible protein-10, and IFN-gamma mRNA transcript levels, particularly in the pancreatic lymph nodes of BBDR rats. Infection with vaccinia virus or H-1 parvovirus induced less stimulation of the innate immune system and failed to induce diabetes in BBDR rats. Our results suggest that the degree to which the innate immune system is activated by TLRs is important for expression of virus-induced diabetes in genetically susceptible hosts.

Influence of flanking sequences on presentation efficiency of a CD8+ cytotoxic T-cell epitope delivered by parvovirus-like particles.

We have previously developed an antigen-delivery system based on hybrid recombinant porcine parvovirus-like particles (PPV-VLPs) formed by the self-assembly of the VP2 protein of PPV carrying a foreign epitope at its N terminus. In this study, different constructs were made containing a CD8(+) T-cell epitope of chicken ovalbumin (OVA) to analyse the influence of the sequence inserted into VP2 on the correct processing of VLPs by antigen-presenting cells. We analysed the presentation of the OVA epitope inserted without flanking sequences or with either different natural flanking sequences or with the natural flanking sequences of a CD8(+) T-cell epitope from the lymphocytic choriomeningitis virus nucleoprotein, and as a dimer with or without linker sequences. All constructs were studied in terms of level of expression, assembly of VLPs and ability to deliver the inserted epitope into the MHC I pathway. The presentation of the OVA epitope was considerably improved by insertion of short natural flanking sequences, which indicated the relevance of the flanking sequences on the processing of PPV-VLPs. Only PPV-VLPs carrying two copies of the OVA epitope linked by two glycines were able to be properly processed, suggesting that the introduction of flexible residues between the two consecutive OVA epitopes may be necessary for the correct presentation of these dimers by PPV-VLPs. These results provide information to improve the insertion of epitopes into PPV-VLPs to facilitate their processing and presentation by MHC class I molecules.

[Diagnosis of parvovirus B19 infection in patients with secondary immunodeficiency diseases]. / Laboratornaia immunodiagnostika infektsii, vyzvannoi parvovirusom B19, u bol'nykh vtorichnymi immunodefitsitami.

The method of immune-enzyme assay was used to examine 113 patients with secondary immunodeficiency, including 16 HIV-infected drug-addicts (group 1), 36 patients with cytomegalovirus infection (CMVI) and with immunoregating index CD4/CD8 below 1.0 (group 2), 30 patients with CMVI and with CD4/CD8 below 1.2 (group 3) and 31 patients with aplastic anemia and with anemia of unclear genesis (group 4), for parvovirus infection caused by parvovirus B19. As for groups 1 and 4, the antibodies were detected in 50 and 48.4% of cases; it is noteworthy that an active parvovirus infection was registered in the above groups more often than in groups 2 and 3. There were patients with the antibodies in group 2 by 1.8 times more than in group 3. It is suggested that the simultaneous impact of HIV, CMV and parvoviruses significantly aggravates the immunodeficiency and contributes to a more severe clinical course.

Viral pharmacovigilance study of haemophiliacs receiving porcine factor VIII.

Porcine factor VIII (FVIII; Hyate:C; Speywood Biopharm Ltd, UK) has been used since 1980 for the treatment both of patients with acquired haemophilia and those with congenital haemophilia and inhibitory antibodies. Each batch is extensively screened using cell-culture techniques to confirm the absence of viruses. The production process does not incorporate specific virucidal treatment steps, such as heat treatment or the addition of a solvent/detergent mixture. Low levels of porcine parvovirus were detected in some batches of the product in late 1996 and supply was suspended. In this retrospective study, sera from 81 recipients of porcine FVIII and 125 other volunteers were screened for evidence of antibodies against a range of porcine viruses: porcine parvovirus (PPV), encephalomyocarditis virus (EMCV), and porcine respiratory and reproductive syndrome virus (PRRSV). The 125 volunteer controls included subjects from six categories: healthy control subjects, pig abattoir personnel, personnel involved in the manufacture of porcine FVIII, recipients of porcine heparin, recipients of porcine insulin, and haemophiliacs treated only with human FVIII. No antibodies to PPV or PRRSV were detected in any subject. Four patients and two volunteers were found to have antibodies to EMCV, but this incidence is similar to that observed in the general population. In conclusion, there was no evidence of transmission of PPR or other marker porcine virus associated with the use of porcine FVIII concentrate (Hyate: C).

Parvoviral infection of endothelial cells and its possible role in vasculitis and autoimmune diseases.

OBJECTIVE: To analyze a series of biopsies from 16 patients who, on the basis of clinical and dermatopathologic findings, had a spectrum of connective tissue diseases (CTD), autoinflammatory or CTD-like syndromes for parvoviral DNA, RNA, and protein. METHODS: Most of the patients were initially screened for parvoviral-related IgG and IgM antibodies. Parvoviral DNA was analyzed by solution phase polymerase chain reaction (PCR). In situ localization of viral VP1 RNA was accomplished by in situ reverse transcriptase (RT) PCR; viral protein (VP2) was detected by immunohistochemistry and these results correlated with the histologic findings. (J Rheumatol 2002;29:xxxx) RESULTS: Of 11 people tested, 10 had either IgG or IgM specific antibodies against parvovirus. Common histologic features of the 16 cases included an interface dermatitis, interstitial histiocytic infiltration with variable collagen necrobiosis, a mononuclear cell dominant vasculitis, and interstitial neutrophilia. Detection of parvoviral RNA by in situ RT-PCR in 14 of 16 cases corroborated solution phase PCR data and demonstrated that the endothelial cells and surrounding mononuclear cells were the viral target. Viral protein as revealed by immunohistochemisty showed an equivalent histologic distribution. Anti-tumor necrosis factor-alpha (TNF-alpha) therapy (etanercept) yielded dramatic improvement after worsening of symptoms with traditional immunosuppressive therapy in the 3 patients in whom this drug was administered; TNF-alpha mRNA was detected by in situ RT-PCR in the area of parvoviral infected cells. CONCLUSION: Parvoviral induced endothelialitis may be responsible for cases of "idiopathic" CTD.

Development of hypertrophic osteodystrophy and antibody response in a litter of vaccinated Weimaraner puppies.

Two different vaccination protocols were compared with regard to the development of hypertrophic osteodystrophy (HOD) (also termed metaphyseal osteopathy) and effectiveness of immunisation in a litter of 10 Weimaraner puppies. Five puppies (group 1) were vaccinated with a modified live canine parvovirus vaccine (CPV) and then two weeks later with a trivalent vaccine containing modified live canine distemper virus and adenovirus type 2 combined with a Leptospira bacterin (DHL). The CPV and DHL vaccine protocols were administered a further two times, at two-week intervals. Group 2 was vaccinated with three consecutive multivalent vaccines containing modified live canine distemper virus, canine parvovirus, parainfluenza and adenovirus type 2 combined with a Leptospira bacterin, at four-week intervals. All puppies were first vaccinated at the age of eight weeks. Three dogs in group 1 developed HOD, while all five dogs in group 2 developed HOD during the study period. Dogs in group 2 had more episodes of HOD than those in group 1. Dogs in group 1 developed higher antibody titres to canine distemper virus and parvovirus compared with those in group 2. Only two out of the 10 dogs developed protective antibody titres to parvovirus. The results of this study suggest that the two different vaccination protocols affected the pattern of appearance of HOD and immunisation in this litter of Weimaraner puppies. The results obtained and the previously reported data suggest that a larger controlled study is needed to further elucidate the effect of different vaccination protocols on HOD and immunisation in Weimaraner puppies.

Investigation of porcine parvovirus among persons with hemophilia receiving Hyate:C porcine factor VIII concentrate.

BACKGROUND: Porcine clotting factor has been used for more than 15 years to treat severe bleeding episodes in persons with hemophilia who have antibodies to human clotting factor. In 1996, QC procedures revealed for the first time the presence of porcine parvovirus (PPV) in the product. This report describes an investigation to determine the extent of product contamination and to evaluate past recipients of porcine clotting factor (Hyate:C, Speywood Biopharm) for evidence of PPV infection. STUDY DESIGN AND METHODS: Stored specimens from 22 lots of previously released Hyate:C were tested for the presence of PPV DNA by PCR and nested PCR assays. Serum specimens from 98 recipients of Hyate:C and 24 controls who did not receive Hyate:C were tested for PPV antibodies by an immunofluorescence assay. RESULTS: PPV DNA was detected in product from 21 of the 22 lots of Hyate:C, primarily by nested PCR testing. In contrast, none of the serum specimens from the 98 Hyate:C recipients tested positive for PPV IgG antibodies. CONCLUSION: The risk of human disease from percutaneous exposure to low levels of PPV seems to be low. Nevertheless, the theoretical risk of human infection with PPV has led to manufacturing changes, including PCR screening of all porcine plasma, which are designed to eliminate this risk.

[Seroprevalence versus Parvovirus B19 in blood donors]. / Seroprevalencia frente a Parvovirus B19 en donantes de sangre.

BACKGROUND: The aim of the study was to describe the seroprevalence against Parvovirus B19 in a random sample of blood donors in the Hospital Universitario de Salamanca. METHODS: We studied the presence of IgG and IgM antibodies against Parvovirus B19 in 136 sera from asymptomatic blood donors by enzyme immunoassay methods. RESULTS: From 136 samples tested, 88 (64.7%) had positive absorbance values for IgG. Forty eight samples (35.5%) were negative. IgM was negative in all cases. We did not find indeterminate results. DISCUSSION: Parvovirus primoinfection usually happens in the childhood. Thus, we can expect a high percentage of general population to have antibodies against Parvovirus B19. Anti-Parvovirus B19 antibodies prevalence in blood donors was 64.7%. This failure is similar to data reported before (65%). Clinical importance of these viruses in currently related with hemathopoyesis diseases and with the possible role in theratogenesis. The presence of IgG seems to give protection except in some chronic infections recently described.

Rheumatic manifestations due to human parvovirus B19. A report of four cases.

Human parvovirus B19 has been incriminated in the genesis of hematologic, dermatologic, neurologic, and rheumatic disorders. We report four cases in which inflammatory rheumatic manifestations developed during the course of human parvovirus B19 infection documented by the presence of IgM and IgG antibodies. There was one case each of monoarthritis, oligoarthritis, polyarthritis, and enthesitis. Three patients had a favorable outcome under nonsteroidal antiinflammatory drug therapy, and one developed reflex sympathetic dystrophy syndrome. In patients with inflammatory rheumatic manifestations that do not fit any specific diagnosis, a careful family history can provide evidence suggesting human parvovirus B19 infection, which should be confirmed by tests for IgM and IgG antibodies.

Financial evaluation of vaccination and testing alternatives for control of parvovirus-induced reproductive failure in swine.

OBJECTIVE: To identify the preferable testing and vaccination strategy for control of porcine parvovirus (PPV) during a 6-month period. DESIGN: Decision-tree analysis and computer simulations. SAMPLE POPULATION: Computer modeling of 300-sow farrow-to-finish herd. PROCEDURE: Serologic testing of 30 females to estimate herd PPV prevalence versus not testing any females was the initial decision alternative. On the basis of serologic test results, herds were classified into 1 of 3 PPV-risk categories: low (> or = 80% seropositive females), moderate (40 to < 80% seropositive females), or high (< 40% seropositive females). Vaccinating all females, only gilts, or not vaccinating was the second decision alternative. RESULTS: For initial model assumptions (test sensitivity and specificity = 0.95; test cost = $5/female; vaccination cost = $0.30/dose; vaccination efficacy = 0.95; and foregone gross margin = $10.85/pig), vaccination of all females (with or without serologic testing) was preferable, but the financially preferable option was to omit serologic testing. Most profitable vaccination option varied with foregone gross margin, vaccination cost, and efficacy. For herds in which all sows were known to be immune, vaccinating only gilts was financially preferable, and serologic testing was not warranted. Variation is expected monetary losses was less in vaccination options than with nonvaccination. CLINICAL IMPLICATIONS: For most herds in the United States, serologic screening for PPV prior to selection of a vaccination program is unlikely to be cost-effective, because vaccination is inexpensive ($0.30/dose) and effective (95%). At current profit margins ($10.85/pig), vaccination of all females has the least-risk and is the preferred option.

A serologic survey of selected viral and bacterial diseases of European wild hogs, Great Smoky Mountains National Park, USA.

Blood samples were collected from 108 wild hogs (Sus scrofa) from the Great Smoky Mountains National Park (GSMNP), USA, February to July 1990. We found no antibodies for swine brucellosis, pseudorabies, bovine virus diarrhea virus or porcine rotavirus infection. Antibody titers to porcine parvovirus were found in 15 (14%) samples and antibody to one or more leptospiral serovars was found in 48 (44%) samples. Thirty-nine (89%) of the 44 positive samples reacted to all five leptospiral serovars tested.

Structure determination of feline panleukopenia virus empty particles.

Various crystal forms of the single-stranded DNA, feline panleukopenia virus (FPV), a parvovirus, have been grown of both full virions and empty particles. The structure of empty particles crystallized in an orthorhombic space group P2(1)2(1)2(1), with unit cell dimensions a = 380.1 A, b = 379.3 A, and c = 350.9 A, has been determined to 3.3 A resolution. The data were collected using oscillation photography with synchrotron radiation. The orientations of the empty capsids in the unit cell were determined using a self-rotation function and their positions were obtained with an R-factor search using canine parvovirus (CPV) as a model. Phases were then calculated, based on the CPV model, to 6.0 A resolution and gradually extended to 3.3 A resolution by molecular replacement electron density averaging. The resultant electron density was readily interpreted in terms of the known amino acid sequence. The structure is contrasted to that of CPV in terms of host range, neutralization by antibodies, hemagglutination properties, and binding of genomic DNA.

Canine parvovirus.

Canine parvovirus is a truly new pathogen of dogs that emerged in the late 1970s. Initially seen as epidemic disease in all dogs, parvoviral enteritis is now primarily a disease of 1- to 6-month-old dogs. Maternal antibody interference with immunization accounts for the vast majority of vaccine "breaks." Molecular virologic methods have revealed continued evolution of the virus, but this appears to be of greater academic than practical interest. Clinical diagnosis can be definitive in fulminant cases but requires laboratory support--usually demonstration of virus in the feces--in less clear-cut cases. Treatment remains symptomatic, based simply on principles of good supportive care. As the virus is firmly entrenched in both the wild and domestic canine population, elimination of the virus is impossible, and CPV-2 will remain a concern for the small animal practitioner indefinitely.

Canine parvovirus effect on wolf population change and pup survival.

Canine parvovirus infected wild canids more than a decade ago, but no population effect has been documented. In wild Minnesota wolves (Canis lupus) over a 12-yr period, the annual percent population increase and proportion of pups each were inversely related to the percentage of wolves serologically positive to the disease. Although these effects did not seem to retard this large extant population, similar relationships in more isolated wolf populations might hinder recovery of this endangered and threatened species.

B-cell epitopes of canine parvovirus: distribution on the primary structure and exposure on the viral surface.

Ten antigenic sites on canine parvovirus (CPV) were mapped with a complete set of overlapping nonapeptides of the capsid proteins VP1 and VP2: five of these sites were recognized by sera from CPV-infected dogs, three were recognized by a rabbit anti-CPV antiserum, and two were recognized by murine monoclonal anti-CPV antibodies. A region covering the first 21 amino-terminal amino acid residues of VP2 was recognized by three sera from infected dogs, one neutralizing rabbit antiserum, and one neutralizing murine monoclonal antibody. Immunoabsorption experiments with full virions indicated that at least 6 of the 10 antigenic sites are located on the surface. Of these six, three sites occur in the amino terminus of VP2. When superimposed on the three-dimensional structure of canine parvovirus (J. Tsao, M. S. Chapman, M. Agbandje, W. Keller, K. Smith, H. Wu, M. Luo, T. J. Smith, M. G. Rossmann, R. W. Compans, and C. R. Parrish, Science 251:1456-1464, 1991), the other three epitopes are located on two loops of VP2 which form the highly exposed "spike" around the threefold-symmetry axis of the virus. Thus, these regions (amino terminus and loops 1 and 3) are of interest as major target sites for induction of neutralizing antibodies.

A new method for rapidly removing contaminating micro-organisms from porcine parvovirus or pseudorabies virus master-seed suspensions.

Virus-contaminated cell cultures are a major problem in the bio-industry. Methods employed to date to remove contaminating micro-organisms are slow and costly, and a new method is proposed here which is simple and rapid. The method uses polyacrylamide beads coated with specific antibodies which yielded bead-antibody-virus complexes when suspended in the virus solution to be cleared. The purified virus was propagated in cells which show phagocytic activity. Vaccine master-seed virus is shown to be rapidly cleaned and propagated using this method.