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E Paoletti

Publications and source records attributed to E Paoletti.

At least 127 records · Page 7Linked to original sources
PubMed1990

Nucleotide sequence analysis of a 10.5 kbp HindIII fragment of fowlpox virus: relatedness to the central portion of the vaccinia virus HindIII D region.

The nucleotide sequence of a 10465 bp HindIII genomic fragment from fowlpox virus (FPV) is presented. Analysis of the nucleotide sequence revealed 10 potential major open reading frames (ORFs). Five of these ORFs are predicted to encode polypeptides with significant homology to hypothetical polypeptides derived from nucleotide sequence analysis of the vaccinia virus (VV) HindIII D region. Interestingly, these homologous ORFs do not occur in the same tandem arrangement in the FPV genome as they do in the VV genome. These results are discussed.

Amino Acid Sequence↗
PubMed1990

Poxvirus recombinant vaccines.

The poxvirus family, subfamily Chordopoxviridae, contains six genera. The basic criteria distinguishing membership in a genus is cross-neutralization and host-range predilection. Members of the genus Orthopoxvirus (vaccinia) and of the genus Avipoxvirus (fowlpox) have been genetically engineered to express genes from heterologous pathogens, thus providing a means of assessing these recombinant viruses as live recombinant vaccines. Vaccinia virus recombinants which have a broad host range can be useful vectors for both human and veterinary applications, while fowlpox virus recombinants, with a host range restricted to avian species, provide useful vectors for application to poultry diseases. Significantly, avipoxviruses have also been shown to be useful as vaccinating vectors in non-avian species. The results presented in this paper were selected to provide the reader with a sense of the extensive potential present in recombinant poxviruses as live recombinant vaccine candidates. The broad host range of vaccinia vectors and the narrower host range of avipoxvirus provide interesting applications. The surprising results obtained in non-avian species with recombinant fowlpox viruses are quite intriguing. The ability to generate a recombinant live vaccine that can readily be amplified in tissue culture, yet is non-proliferative in vivo, provides unique properties and interesting potential applications.

Animals↗
PubMed1990

Newcastle disease virus fusion protein expressed in a fowlpox virus recombinant confers protection in chickens.

A cDNA copy of the RNA encoding the fusion (F) protein of Newcastle disease virus (NDV) strain Texas, a velogenic strain of NDV, was obtained and the sequence was determined. The 1,792-base-pair sequence encodes a protein of 553 amino acids which has essential features previously established for the F protein of virulent NDV strains. These include the presence of three strongly hydrophobic regions and pairs of dibasic amino acids in the pentapeptide Arg-Arg-Gln-Arg-Arg preceding the putative cleavage site. When inserted into a fowlpox virus vector, a glycosylated protein was expressed and presented on the surface of infected chicken embryo fibroblast cells. The F protein expressed by the recombinant fowlpox virus was cleaved into two polypeptides. When inoculated into susceptible birds by a variety of routes, an immunological response was induced. Ocular or oral administration of the recombinant fowlpox virus gave partial protection, whereas both intramuscular and wing-web routes of inoculation gave complete protection after a single inoculation.

Amino Acid Sequence↗
PubMed1990

Coexpression by vaccinia virus recombinants of equine herpesvirus 1 glycoproteins gp13 and gp14 results in potentiated immunity.

The equine herpesvirus 1 glycoprotein 14 (EHV-1 gp14) gene was cloned, sequenced, and expressed by vaccinia virus recombinants. Recombinant virus vP613 elicited the production of EHV-1-neutralizing antibodies in guinea pigs and was effective in protecting hamsters from subsequent lethal EHV-1 challenge. Coexpression of EHV-1 gp14 in vaccinia virus recombinant vP634 along with EHV-1 gp13 (P. Guo, S. Goebel, S. Davis, M. E. Perkus, B. Languet, P. Desmettre, G. Allen, and E. Paoletti, J. Virol. 63:4189-4198, 1989) greatly enhanced the protective efficacy in the hamster challenge model over that obtained with single recombinants. The inoculum doses (log10) required for protection of 50% of hamsters were 6.1 (EHV-1 gp13), 5.2 (EHV-1 gp14), and less than 3.6 (vaccinia virus recombinant expressing both EHV-1 glycoproteins [gp13 and gp14]).

Amino Acid Sequence↗
PubMed1990

Development of a specific serological test and an efficient subunit vaccine to control bovine leukemia virus infection.

Study of the antigenic structure of the Bovine Leukemia Virus (BLV) envelope glycoprotein gp51 with a panel of mouse monoclonal antibodies (MAbs) has allowed the identification of biologically important determinants directly involved in the infectivity of BLV. Considering the various facts reported in this paper, it follows that diagnostic and vaccination procedures that make use of gp51 in a native configuration constitute a prerequisite for the design of an efficient BLV eradication program. To improve the efficacy of a serological detection test, MAbs have been selected as reagents of choice to develop a competition enzyme-linked immunosorbent assay (cELISA). Recombinant vaccinia virus expressing gp51 and gp30 was indicated as a very promising protective vaccine against BLV infection.

Amino Acid Sequence↗
PubMed1990

Efficacy of recombinant erythropoietin after subcutaneous or intraperitoneal administration to patients on CAPD.

Recombinant erythropoietin (R-EPO) administered i.v. is effective in correcting anemia in patients on hemodialysis (HD). As subcutaneous (s.c.) or intraperitoneal (i.p.) dosing would be preferable in CAPD patients, we have evaluated its efficacy when given by these routes. Sixteen CAPD patients (mean Hb 7.3 +/- 1.6 g/dl) have been divided into two groups: group A received s.c. self-administered R-EPO (starting dose 92 +/- 35 U/kg/week) two times a week; in group B R-EPO was given i.p. (170 +/- 42 U/kg/week) thrice weekly. The observation period lasted about 12 months. All patients reached a target Hb greater than 10 g/dl. Group A achieved a full response within 9 +/- 2 weeks, group B within 13 +/- 1.7 (p less than 0.005). In group A the starting R-EPO dose was not changed; in group B it was increased to 225 +/- 45 U/kg/week. We observed no differences in the incidence of peritonitis in the two groups. Our findings show that both R-EPO administration routes are safe and efficient in correcting anemia in patients on CAPD. A shorter period of treatment and lower doses of R-EPO seem to be required to achieve the same target Hb level when using the s.c. rather than the i.p. application route.

Anemia↗
PubMed1990

Poxvirus-based vectors as vaccine candidates.

The advent of recombinant DNA techniques and advances in immunology have provided a means for dissecting the immunobiology of disease-causing agents. Identification and expression of individual genes from the pathogens in heterologous systems, such as VV, have yielded valuable information regarding structural properties of the gene products and their role in eliciting protective immunity. Targets of both humoral and/or cellular immunity for many disease-causing agents have been identified or confirmed using a VV expression system (Section IV). Additionally, specific VV recombinants have induced a protective immune response in experimental animals. The ability of VV recombinants to induce pertinent immune responses necessary for protection, the potential to develop polyvalent vaccines, and the successful history of VV as an immunizing agent provide the impetus for engineering VV as a live recombinant vaccine candidate. Critical to the refinement of poxviruses as recombinant immunizing agents is a more in-depth knowledge of the molecular biology of these viruses. Although significant advances have been made in this area within the past 10 years, a greater understanding of the mechanisms governing gene expression and viral virulence factors should enable the development of more safe and effective vaccine candidates. Progression of VV vector technology to other members of the poxvirus family has been successful. Development of other poxviruses as vectors may, therefore, provide a means of generating host-restricted vaccines. Fowlpox recombinant viruses, for instance, may yield candidate vaccines in the poultry industry. Interestingly, it was also demonstrated that these host-restricted recombinant viruses can be used as immunizing vehicles in other species. The ability of a nonreplicating viral vector to elicit a protective immune response is especially intriguing in light of the observation by Morgan et al. that a VV/EBV gp340/220 recombinant, derived from an avirulent VV strain, was unable to protect cottontop tamarins from a live EBV challenge.

Animals↗
PubMed1989

Regulation of expression of herpes simplex virus (HSV) glycoprotein D in vaccinia recombinants affects their ability to protect from cutaneous HSV-2 disease.

The effect of regulation of herpes simplex virus (HSV) type 1 glycoprotein D (gD-1) gene expression on HSV-specific immune response and protection from cutaneous HSV-2 disease was studied using vaccinia virus recombinants containing gD-1 under the control of early (VP176) or late (VP254) vaccinia virus promoters. Expression of gD-1 in VP176-infected cells was first observed at 2 h after infection. It did not depend on viral DNA replication. In VP254-infected cells, gD-1 was first observed at 24 h after infection and its expression depended on DNA replication. Immunized guinea pigs had similar titers of HSV-specific neutralizing antibody. However, HSV-specific T cell responses were significantly higher in VP176- than in VP254-immunized animals as determined by lymphoproliferation (P less than .005) and delayed type hypersensitivity (P less than .01). The reduced T cell responses of VP254-immunized guinea pigs correlated with poor gD-1 expression in VP254-infected antigen presenting cells (splenic adherent and epidermal cells). Immunization with VP176, but not with VP254, protected guinea pigs from primary (P less than .0005) and recurrent (P less than .0005) cutaneous HSV-2 lesions.

Animals↗
PubMed1989

Antibody-dependent cellular cytotoxicity is directed against both the gp120 and gp41 envelope proteins of HIV.

To define the target antigens for antibody-dependent cellular cytotoxicity (ADCC), assays were performed using affinity-purified human immunoglobulin (Ig) or polyclonal rabbit sera directed against specific proteins of HIV. ADCC was not found using affinity-purified anti-core (p25) human Ig or sera obtained from rabbits hyper-immunized with recombinant p25. However, when affinity-purified human Ig or rabbit antisera specific for the envelope glycoproteins, gp120 or gp41, were used in ADCC assays, killing of HIV-infected cells was observed. These results indicate that antibodies in the infected individual that mediate ADCC are directed against both the gp120 and gp41 HIV envelope proteins and not against the viral core protein.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1989

Antigen-presenting capacity of epidermal cells infected with vaccinia virus recombinants containing the herpes simplex virus glycoprotein D, and protective immunity.

We studied the association of herpes simplex type 1 (HSV-1) glycoprotein D (gD-1) expression in epidermal cells (EC) with virus-specific immunity and protection of mice from fatal HSV-2 challenge. Vaccinia virus recombinants containing gD-1 under the control of an early (VP176) or late (VP254) vaccinia virus promoter were used. Mature gD-1 protein was expressed in VP176-infected EC and they had accessory cell function for HSV-2-induced T cell proliferation of immune lymph node cells (LNC). It was not expressed in VP254-infected EC and they did not act as accessory cells. LNC from VP176- but not VP254-immunized mice proliferated in response to HSV antigen and only VP176-immunized mice had complete long-term protection from HSV-2 challenge.

Animals↗
PubMed1989

Expression in recombinant vaccinia virus of the equine herpesvirus 1 gene encoding glycoprotein gp13 and protection of immunized animals.

The equine herpesvirus 1 (EHV-1) gene encoding glycoprotein 13 (gp13) was cloned into the hemagglutinin (HA) locus of vaccinia virus (Copenhagen strain). Expression of the gp13 gene was driven by the early/late vaccinia virus H6 promoter. Metabolically radiolabeled polypeptides of approximately 47 and 44 kilodaltons and 90 kilodaltons (glycosylated form) were precipitated with both polyclonal and gp13-specific monoclonal antibodies. Presentation of gp13 on the cytoplasmic membrane of cells infected with the recombinant gp13 vaccinia virus was demonstrated by immunofluorescence of unfixed cells. Inoculation of the recombinant gp13 vaccinia virus into guinea pigs induced neutralizing antibodies to both EHV-1 and vaccinia virus. Hamsters vaccinated with the recombinant gp13 vaccinia virus survived a lethal challenge with the hamster-adapted Kentucky strain of EHV-1. These results indicate that expression in vaccinia virus vectors of EHV-1 gp13, the glycoprotein homolog of herpes simplex virus gC-1 and gC-2, pseudorabies virus gIII, and the varicella-zoster virus gpV may provide useful vaccine candidates for equine herpesvirus infections.

Animals↗
PubMed1989

M protein (M1) of influenza virus: antigenic analysis and intracellular localization with monoclonal antibodies.

A panel of 16 monoclonal antibodies recognizing M protein (M1) of influenza virus was generated. Competition analyses resulted in localization of 14 monoclonal antibodies to three antigenic sites. Three monoclonal antibodies localized to site 1B recognized a peptide synthesized to M1 (residues 220 to 236) with enzyme-linked immunosorbent assay titers equivalent to or greater than that seen with purified M1; therefore, site 1B is located near the C terminus of M1. Sites 2 and 3 localize to the N-terminal half of M1. Antigenic variation of M proteins was seen when the monoclonal antibodies were tested against 14 strains of type A influenza viruses. Several monoclonal antibodies showed specific recognition of A/PR/8/34 and A/USSR/90/77 M proteins and little or no reactivity for all other strains tested. Immunofluorescence analysis with the monoclonal antibodies showed migration of M protein to the nucleus during the replicative cycle and demonstrated association of M protein with actin filaments in the cytoplasm. Use of a vaccinia virus recombinant containing the M-protein gene demonstrated migration of M protein to the nucleus in the absence of synthesis of gene products from other influenza virus RNA segments.

Amino Acid Sequence↗
PubMed1989

Cloning and expression of foreign genes in vaccinia virus, using a host range selection system.

A simple selection system has been developed for the cloning and expression of open reading frames in vaccinia virus. The selection system is based on a conditional lethal (host range) mutant of vaccinia virus. A deletion mutant of the vaccinia virus WR strain was generated by insertion of the neomycin resistance gene from transposon Tn5 and selection with the antibiotic G418. This deletion recombinant, vP293, lacked approximately 21.7 kilobases of DNA beginning 3.8 kilobases from the left end of the genome, vP293, was capable of plaquing on primary chicken embryo fibroblasts and two monkey cell lines (BSC-40 and Vero) but was defective in replication in the human cell line MRC-5. Insertion of the host range gene K1L into vP293 restored the ability to grow on MRC-5 cells. A series of plasmids were constructed which in addition to the K1L gene contained a vaccinia virus early-late promoter, H6, followed by a unique polylinker sequence, translational initiation and termination signals, and an early transcription termination signal. These plasmids, pHES1 through 4, allowed for rapid single-step cloning and expression of any open reading frame when recombined in vivo with vP293 and scored for growth on MRC-5 cells.

Cell Line↗
PubMed1988

Expression of herpes simplex virus glycoprotein D on antigen presenting cells infected with vaccinia recombinants and protective immunity.

We studied the effect of the temporal regulation of herpes simplex virus (HSV) type 1 glycoprotein D (gD-1) expression in Ia+ epidermal cells (EC) and macrophages on virus specific immunity and protection from HSV-2 challenge. gD-1 was expressed on the surface of cells infected with a vaccinia recombinant containing gD-1 under the control of an early vaccinia virus promoter (VP176). It was not expressed in cells infected with a recombinant (VP254) in which gD-1 is controlled by a late vaccinia virus promoter. BALB/c mice immunized with both recombinants seroconverted to HSV-2 as determined by neutralization. However, HSV specific delayed type hypersensitivity (DTH) responses were significantly (p less than 0.025) higher in VP176 than VP254 immunized animals. Both VP176 and VP254 immunized mice were protected from severe neurological disease due to HSV-2 challenge at 14 days post immunization, but long term protection was observed only in VP176 immunized mice.

Animals↗
PubMed1988

Fowlpox virus as a vector in non-avian species.

Examination of the members of the Poxvirus family reveals a large and diverse group with members infecting almost every animal species. To a large extent, members of the individual genera have a broad host range and infect a number of animal species, although, as Baxby has pointed out, successful experimental inoculation of a species does not necessarily mean that this species provides a natural host for that virus. Avipox viruses, together with swinepox virus occupy a somewhat unique position in possessing a restricted host range. We have taken advantage of this restricted host range in fowlpox virus to engineer recombinant vector viruses for use in the poultry industry and in vaccination of non-avian species.

Animals↗
PubMed1988

Recombinant fowlpox virus inducing protective immunity in non-avian species.

The natural host of fowlpox virus is limited to avian species. When inoculated into non-avian tissue culture cells, however, fowlpox virus can initiate an abortive infection. A fowlpox virus was engineered to express rabies virus glycoprotein. On inoculation of the recombinant virus into either avian (permissive) or non-avian (non-permissive) cells, the rabies glycoprotein was expressed as a membrane-associated antigen. Inoculation of the fowlpox virus recombinant into six different species of mammal resulted in specific immune responses to both fowlpox antigens and to rabies glycoprotein. In mice, cats and dogs the immune response was sufficient to protect against a live rabies virus challenge. The results demonstrate the utility of a fowlpox virus vector in immunizing non-avian species against rabies in the absence of productive viral replication of the fowlpox vector.

Animals↗
PubMed1988

Protective immunity against avian influenza induced by a fowlpox virus recombinant.

Fowlpox virus, the prototypic virus of the genus Avipoxvirus has a natural host range limited to avian species. As such, fowlpox virus provides a suitable candidate for the development of a species-specific recombinant viral vector. This paper reports the development of a fowlpox virus recombinant expressing the haemagglutinin molecule from a highly virulent avian influenza virus. On immunization of chickens and turkeys with the recombinant, protection is afforded against a lethal challenge with either the homologous or a heterologous influenza virus strain.

Animals↗