Publications

mutational analysis of v-rel, the oncogene of reticuloendotheliosis virus strain t.	reticuloendotheliosis virus strain t (rev-t) is a highly oncogenic retrovirus that induces a lethal lymphoma in young galliform birds and also transforms and immortalizes avian lymphoid cells in vitro. rev-t presumably arose when a reticuloendotheliosis virus (rev) incorporated a portion of the turkey c-rel gene into its genome, forming the v-rel oncogene. the predicted v-rel protein (p59v-rel) has 14 amino acid substitutions and 3 amino acid deletions relative to the predicted turkey c-rel prot ...	1990	2189101
isolation of marek's disease virus from japanese quail with lymphoproliferative disease.	sixty-one japanese quail from eight flocks with problems of recurring outbreaks of lymphoproliferative diseases resembling marek's disease (md), were examined aetiologically. gross lymphomatous lesions were seen in 17 of the quail and 11 out of 56 quail had md virus (mdv) feather tips antigens. mdv antibody was detectable in only one of 22 quail. none of 9 quail had antibodies against reticuloendotheliosis virus (rev). no mdv was isolated from the total 42 materials of quail using cell culture t ...	1990	18679919
heritable retroviral transgenes are highly expressed in chickens.	this report describes expression of heritable reticuloendotheliosis virus (rev) vector me111 in 20 independent lines of transgenic chickens. the results are strikingly different from studies of moloney virus in transgenic mice, where restricted expression of inherited proviruses has led to their use primarily as insertional mutagens rather than general agents for gene transfer. in contrast, the rev me111 provirus is actively transcribed in a variety of tissues from transgenic chickens, is expres ...	1991	1705705
interaction of the v-rel protein with an nf-kappa b dna binding site.	the avian reticuloendotheliosis virus t contains within its genome the oncogene rel. the expression of this gene is responsible for the induction of lymphoid tumors in birds. recently, the rel gene was shown to be related to the p50 dna binding subunit of the transcription factor complex nf-kappa b. binding sites for the nf-kappa b complex are found in the enhancer regions of a number of genes, including the immunoglobulin kappa gene and the human immunodeficiency virus long terminal repeat. in ...	1991	1848011
gene expression from heterologous promoters in a replication-defective avian retrovirus vector in quail cells.	avian retrovirus vectors, with potential for use in avian transformation, were constructed to evaluate the relative efficiency of promoters placed internal to the viral long terminal repeats (ltr). the vectors are replication-defective reticuloendotheliosis plasmids that contain the neomycin phosphotransferase gene under control of the 5' ltr and an internal promoter that directs expression of the chloramphenicol acetyltransferase gene. the internal promoters were the sv40 early, the mouse metal ...	1991	1652136
the v-rel oncogene of avian reticuloendotheliosis virus transforms immature and mature lymphoid cells of the b cell lineage in vitro.	heavy chain gene rearrangements were analyzed in 67 independently derived reticuloendotheliosis virus (rev-t) transformed avian lymphoid cell lines. the status of the heavy chain genes in these rev-t transformed cell lines was determined, in part, by the age of the chicken whose spleen cells were transformed. cell lines derived by the in vitro transformation of splenic lymphocytes obtained from embryos did not contain heavy chain gene ig rearrangements. by contrast, splenic lymphocytes transform ...	1991	1677223
characterization and comparison of avian and murine helper cell lines for production of replication-defective retroviruses for avian transformation.	several approaches were taken to identify improved helper cell lines for the production of replication-defective avian retroviral vectors for avian transformation. both qt6 and d17 cells were engineered to become helper cell lines for the production of reticuloendotheliosis virus vectors. the results showed that the majority of lines from the d17, qt6, and d17c3 cells produced titers in the 10(2) to 10(3) cfu/ml range, with one qt6 line producing 10(5) cfu/ml. this high producer line was relativ ...	1991	1652135
importance of cell-mediated immunity in marek's disease and other viral tumor diseases.	cell-mediated immune (cmi) responses to viral tumor diseases are often used as examples of the importance of antiviral and antitumor immunity in chickens. especially, reticuloendotheliosis virus (rev) and marek's disease herpesvirus (mdv) are used as models to study the development of cytotoxic t-lymphocytes against viral and tumor antigens and activation of natural killer (nk) cells. major histocompatibility complex class i-restricted, antiviral cytotoxic t-lymphocytes expressing cd4-/cd8+ mark ...	1991	1649464
characterization of large deletions occurring during a single round of retrovirus vector replication: novel deletion mechanism involving errors in strand transfer.	retroviruses mutate at a high rate during replication. we used a spleen necrosis virus-based vector system and helper cell line to characterize mutations occurring during a single round of retrovirus replication. the vector used, jd216hyneo, codes for two drug resistance genes, hygromycin resistance (hygro) and neomycin resistance (neo). the downstream neo gene is expressed only when a mutation alleviates a block to splicing which is located in the upstream hygro gene. the mutations allowing spl ...	1991	1714517
a member of the set of kappa b binding proteins, hiven86a, is a product of the human c-rel proto-oncogene.	hiven86a is an inducible member of a set of cellular proteins that specifically bind to the kappa b enhancer (franza et al., 1987; franza, 1988; franza, 1990; ballard et al., 1989; bohnlein et al., 1988). this enhancer motif has been detected in numerous cellular and viral transcription control domains (boshart et al., 1985; sen & baltimore, 1986; nabel & baltimore, 1987). recently, cdnas have been cloned (kieran et al., 1990; baldwin & sharp, 1987) that encode the 50 kd dna binding subunit of m ...	1991	2030915
expression of v-rel in a replication competent virus: transformation and biochemical characterization.	the avian reticuloendotheliosis virus strain t (rev-t) transforms bone marrow cells and may cause phenotypic changes in fibroblasts. both events are thought to result from expression of the v-rel oncoprotein, a member of the nf-kappa b family of transcription factors. most rev stocks contain a cytopathic and immunosuppressive helper virus (rev-a) unrelated to standard avian retroviruses, and thus the degree to which v-rel expression alone contributes to the transformed phenotype in bone marrow c ...	1991	1656369
reticuloendotheliosis in a wild turkey (meleagris gallopavo) from coastal georgia.	an emaciated wild turkey (meleagris gallopavo) exhibiting neurologic signs was found on ossabaw island, chatham county, georgia (usa) on 11 april 1989. the neurologic abnormalities observed included ataxia, drooping wings, head tremors, torticollis, and circling. at necropsy, discrete yellowish-white nodules, varying in size from 2 to 5 mm, were present in the spleen. white nodular lesions approximately 2 mm in diameter were observed beneath the mucosal surface of the distal esophagus. histopath ...	1992	1312647
reticuloendotheliosis and 'pullet disease' in israel.		1992	1313616
spleen necrosis virus, an avian immunosuppressive retrovirus, shares a receptor with the type d simian retroviruses.	the reticuloendotheliosis viruses (rev) are a family of highly related retroviruses isolated from gallinaceous birds. on the basis of sequence comparison and overall genome organization, these viruses are more similar to the mammalian type c retroviruses than to the avian sarcoma/leukemia viruses. the envelope of a member of the rev family, spleen necrosis virus (snv), is about 50% identical in amino acid sequence to the envelope of the type d simian retroviruses. although snv does not productiv ...	1992	1313915
reticuloendotheliosis type c and primate type d oncoretroviruses are members of the same receptor interference group.	the reticuloendotheliosis viruses (revs), originally isolated from avian species, constitute a group of retroviruses which are more closely related to mammalian retroviruses than to other avian retroviruses. the envelope glycoproteins of members of the rev group display a striking amino acid sequence identity with a group of primate oncoretroviruses which belong to a single receptor interference group and include all of the type d and some type c primate oncoretroviruses. members of the rev grou ...	1992	1316460
alterations within pp59v-rel-containing protein complexes following the stimulation of rev-t-transformed lymphoid cells with zinc.	pp59v-rel exists in association with specific cellular proteins within lymphoid cells transformed by reticuloendotheliosis virus (rev-t). these include the cellular rel homolog (p75c-rel) as well as a 40-kda avian homolog to i kappa b. the brief exposure of rev-t-transformed lymphoid cells to micromolar concentrations of znso4 induces profound alterations within these protein complexes. most of the constituents of the rel protein complexes (to include pp59v-rel, p75c-rel, and p115) translocate f ...	1992	1316681
differentiation of pathogenic and non-pathogenic serotype 1 marek's disease viruses (mdvs) by the polymerase chain reaction amplification of the tandem direct repeats within the mdv genome.	there are no simple, direct methods to reliably distinguish oncogenic serotype 1 marek's disease viruses (mdvs) from their attenuated variants. the present study was an attempt to apply polymerase chain reaction (pcr) to develop a rapid and sensitive assay for the presence of the mdv genome. pcr oligos were chosen to flank the 132-base-pair tandem direct repeats in the serotype 1 mdv genome. the pcr reaction was specific for serotype 1 mdvs, amplifying fragments corresponding to one to three cop ...	1992	1329706
analytical study of avian reticuloendotheliosis virus dimeric rna generated in vivo and in vitro.	the retroviral genome consists of two identical rna molecules associated at their 5' ends by a stable structure called the dimer linkage structure. the dimer linkage structure, while maintaining the dimer state of the retroviral genome, might also be involved in packaging and reverse transcription, as well as recombination during proviral dna synthesis. to study the dimer structure of the retroviral genome and the mechanism of dimerization, we analyzed features of the dimeric genome of reticuloe ...	1992	1331519
cell-mediated cytolysis of lymphoblastoid cells expressing marek's disease virus-specific phosphorylated polypeptides.	cell-mediated immune responses against marek's disease virus (mdv)-antigens were examined using reticuloendotheliosis virus (rev)-transformed lymphoblastoid cell line cu91 and three cell lines derived from cu91. cu210 was established by establishing a latent mdv infection in cu91. transfection of cu210 with pnl1, a selectable plasmid or with pnl1 and the cloned bamhi a fragment of mdv dna resulted in the establishment of cu212 and cu211, respectively. cu211 expressed a mdv-specific phosphorylate ...	1992	1336254
the cytotoxic t lymphocyte response in reticuloendotheliosis virus-infected chickens is mediated by alpha beta and not by gamma delta t cells.	we induced a virus-specific cytotoxic t lymphocyte (ctl) response in b2 chickens by i.v. inoculation with 100 tcid50 of the reticuloendotheliosis virus (rev). chickens were sacrificed 7 days after the infection and cytotoxic activity of the spleen cells against various target cells was assayed in a 4 h 51cr-release assay at an effector to target ratio of 100:1. in addition, t cell receptor (tcr) alpha beta and tcr gamma delta cells were negatively selected from the rev-immune spleen cells and us ...	1992	1490734
a spleen necrosis virus-based retroviral vector which expresses two genes from a dicistronic mrna.	we have investigated a novel strategy for coexpressing two genes from a retroviral vector. the 5' nontranslated leader region of at least some picornavirus rnas contains a sequence that can act as an internal ribosome entry site allowing initiation of translation at a downstream aug codon in a 5' cap-independent manner. to investigate whether such a sequence can function in the context of a retroviral vector, we constructed a spleen necrosis virus-based vector carrying two selectable marker gene ...	1992	1310190
retrovirus insertion into herpesvirus in vitro and in vivo.	retroviruses and herpesviruses are naturally occurring pathogens of humans and animals. coinfection of the same host with both these viruses is common. we report here that a retrovirus can integrate directly into a herpesvirus genome. specifically, we demonstrate insertion of a nonacute retrovirus, reticuloendotheliosis virus (rev), into a herpesvirus, marek disease virus (mdv). both viruses are capable of inducing t lymphomas in chickens and often coexist in the same animal. rev dna integration ...	1992	1310544
unusually high frequency of reconstitution of long terminal repeats in u3-minus retrovirus vectors by dna recombination or gene conversion.	recently, we described a retrovirus vector system with which to study formation of cdna genes (r. dornburg and h. m. temin, mol. cell. biol. 6:2328-2334, 1988; mol. cell. biol. 8:64-72, 1990; j. virol. 64:886-889, 1990). for these studies, retrovirus vectors were constructed in which the u3 region of the 3' long terminal repeat (ltr) was deleted. after one round of retrovirus replication, such vectors formed a provirus with two u3-minus ltrs. however, the insertion of some additional sequences i ...	1992	1310753
stable transfection of reticuloendotheliosis virus-transformed lymphoblastoid cell lines.	lymphoblastoid t cell lines were established by infection of chicken splenocytes with reticuloendotheliosis virus (rev). the target cells first were cultured in interleukin-containing conditioned medium or were stimulated by concanavalin a, or both. most cell lines were t cells expressing cd3 and one of the t cell receptors, and all cell lines were positive for major histocompatibility complex (mhc) class ii antigens. several rev-transformed cell lines were stably transfected using electroporati ...	1992	1320872
transcriptional interaction between retroviral long terminal repeats (ltrs): mechanism of 5' ltr suppression and 3' ltr promoter activation of c-myc in avian b-cell lymphomas.	chicken syncytial viruses induce bursal lymphomas by integrating into the c-myc locus and activating myc expression by 3' long terminal repeat (ltr) promoter insertion. in contrast to wild-type proviruses, in which transcription initiates predominantly in the 5'ltr, these myc-associated proviruses exhibit a predominance of transcription from the 3' ltr and little transcription from the 5' ltr. most of these proviruses contain deletions within the 5' end of their genome that spare the 5' ltr. we ...	1992	1321271
the v-rel oncogene: insights into the mechanism of transcriptional activation, repression, and transformation.	the v-rel oncogene product from the avian reticuloendotheliosis virus strain t corresponds to a member of the rel-related family of enhancer-binding proteins that includes both the mammalian 50- and 65-kda subunits of the nf-kappa b transcription factor complex. however, in contrast to nf-kappa b, v-rel has been shown to function as a dominant-negative repressor of kappa b-dependent transcription in many mature cell types. we now demonstrate that a highly conserved motif within the rel homology ...	1992	1321284
the rel family: models for transcriptional regulation and oncogenic transformation.		1992	1327144
reticuloendotheliosis virus long terminal repeat elements are efficient promoters in cells of various species and tissue origin, including human lymphoid cells.	promiscuous transcriptional activity of the reticuloendotheliosis virus (rev) long terminal repeat (ltr) was detected in transient expression assays using ltr-chloramphenicol acetyltransferase-encoding gene chimeras, and cells of diverse species and tissue type; levels of expression from two different rev ltrs correlate with reports of pathogenicity of the respective viruses in vivo. revs do not encode a transactivator targeted to the viral ltr, and cells infected with marek's disease virus, a h ...	1992	1332912
isolation of chicken anaemia virus from broiler chickens.	chicken anaemia virus (cav) infection was demonstrated, by both serology and virus isolation, in 1- to 6-week-old broiler chickens originated from various parent flocks in hungary. total losses in the broiler flocks were estimated at 7 to 8% and about 25% of the chickens failed to reach target body mass by the 7th week of life. the clinical signs, postmortem lesions and histopathological changes of the affected chickens were similar to those of naturally occurring cav-induced infectious anaemia ...	1992	1298167
5-azacytidine and rna secondary structure increase the retrovirus mutation rate.	a broad spectrum of mutations occurs at a high rate during a single round of retrovirus replication (v.k. pathak and h. m. temin, proc. natl. acad. sci. usa 87:6019-6023, 1990). we have now determined that this high rate of spontaneous mutation can be further increased by 5-azacytidine (azc) treatment or by regions of potential rna secondary structure. we found a 13-fold increase in the mutation rate after azc treatment of retrovirus-producing cells and target cells. the azc-induced substitution ...	1992	1373201
characterization of reticuloendotheliosis virus-transformed avian t-lymphoblastoid cell lines infected with marek's disease virus.	the expression of marek's disease virus (mdv) transcripts and protein products was investigated in reticuloendotheliosis virus-transformed avian t-lymphoblastoid cell line recc-cu91, which was superinfected with mdv. the presence of mdv in the superinfected cell line, renamed recc-cu210, was demonstrated by southern hybridization with 32p-labeled bamhi-h and -b fragments of the bamhi mdv dna library. examination of recc-cu210 for the expression of mdv-specific rna transcripts encoded by the inte ...	1992	1279200
protection against reticuloendotheliosis virus-strain t tumours is associated with jmv-1 culture supernatant-enhanced natural killer cell activity.	one-day-old chicks were inoculated intraperitoneally with cell-free jmv-1 culture supernatant and were subsequently challenged with a lethal dose of recc-cu60 tumour cells at either 7 or 12 days of age. a significant reduction in mortality was evidenced in chicks that had been inoculated with jmv-1 culture supernatant prior to recc-cu60 tumour cell challenge at 12 days of age, compared with all other treatment groups. reducing the serum content of jmv-1 culture medium or changing the base medium ...	1992	18670954
preparation and characterization of chicken intraepithelial leukocytes.	intraepithelial leukocytes (iels) form an important component of the intestinal immune system. several methods of preparing chicken iels were compared for cell yield, cell populations, and functional activity against a natural killer (nk)-susceptible lymphoblastoid cell line (lscc-rp9). in addition, an attempt was made to immortalize iels by infection with reticuloendotheliosis virus (rev) for use in cell-trafficking studies. intestinal fragments were incubated in 5 mm dl-dithiothreitol at 41 de ...	1993	18671036
detection of reticuloendotheliosis virus infection using the polymerase chain reaction.	the polymerase chain reaction (pcr) was shown to be a sensitive and useful method for detection of infection by members of the group of avian reticuloendotheliosis virus (rev). genomic dna extracted from chick embryo fibroblasts (cefs), blood and tumours of chickens experimentally infected with the spleen necrosis virus (snv) strain of rev was used as the target for chain elongation. deoxyoligonucleotide primers that encompass a portion of the unique 3', repeat and unique 5' region of the long t ...	1993	18671039
efficient insertion from an internal long terminal repeat (ltr)-ltr sequence on a reticuloendotheliosis virus vector is imprecise and cell specific.	to examine the fidelity and efficiency of integration from a covalently closed long terminal repeat (ltr)-ltr sequence in vivo, we isolated individual spleen necrosis virus proviruses that arose following infection of chicken embryo fibroblasts (cefs) and sequenced the provirus-cell dna junctions. some but not all cef preparations allowed efficient insertion from the internal sequence. moreover, in contrast to integration from the normal ends of the viral dna, which occurs with precision with re ...	1993	8382311
retroviral insertions into a herpesvirus are clustered at the junctions of the short repeat and short unique sequences.	we previously described the integration of a nonacute retrovirus, reticuloendotheliosis virus (rev), into the genome of a herpesvirus, marek disease virus (mdv), following both long-term and short-term coinfection in cultured fibroblasts. the long-term coinfection occurred in the course of attenuating the oncogenicity of the jm strain of mdv and was sustained for > 100 passages. the short-term coinfection, which spanned only 16 passages, was designed to recreate the insertion phenomenon under co ...	1993	8387199
alteration of location of dimer linkage sequence in retroviral rna: little effect on replication or homologous recombination.	retrovirus particles contain a dimer of retroviral genomic rna. a defined region of the retrovirus genome has previously been shown to be important for both dimerization and encapsidation. to study the importance of the position of this encapsidation and dimerization signal for retroviral replication and homologous recombination, we used a previously described spleen necrosis virus-based helper cell system. this system allows retroviral vectors with multiple genetic markers to be studied after a ...	1993	8388494
consistent chromosomal aberration in cell lines transformed with marek's disease herpesvirus: evidence of genomic dna amplification.	a specific chromosomal aberration was observed in 14 of 15 avian lymphoblastoid cell lines transformed with marek's disease herpesvirus. this aberration, designated dup(1p)(p22-p23), appeared as an extra g-positive band and interband on the short arm of one chromosome i homolog. using fluorescent in situ hybridization, we identified amplified genomic dna sequences in this region. this amplification involves sequences linked to an endogenous retrovirus locus and genes in the histone multigene fam ...	1993	8390410
retrovirus insertion into herpesvirus: characterization of a marek's disease virus harboring a solo ltr.	we recently reported the phenomenon of retroviral insertion into a herpesvirus (isfort et al., (1992) proc. natl. acad. sci. usa 89, 991-995). we have now isolated marek's disease virus (mdv) clones that carry retroviral inserts. retroviral ltr insertion has the potential to activate or inactivate herpesvirus genes leading to alterations of the biological properties of the herpesviruses. the structure and the expression pattern of a virus clone carrying a solitary ltr insertion was characterized ...	1993	8390750
a survey of an antibody to reticuloendotheliosis virus in sera of chickens and other avian species in japan.	an examination of antibody to reticuloendotheliosis virus (rev) in sera of chickens and other avian species collected from various districts in japan was carried out. agar gel immunodiffusion test (agid) to the chicken sera revealed positive results in 25.9% of the 54 farms, 21.4% of the 126 flocks and 14.3% of the 1,892 individual chickens. all the agid positive sera also were positive in indirect immunofluorescence and/or virus neutralization tests. in avian species other than chickens, peking ...	1993	8286554
flow cytometric analysis of the neutralizing immune response against infectious bursal disease virus using reticuloendotheliosis virus-transformed lymphoblastoid cell lines.	infectious bursal disease virus (ibdv) is a lymphotropic virus with cytocidal effect on b lymphocytes of the bursa of fabricius. we investigated the susceptibility of clonal populations of reticuloendotheliosis virus-transformed chicken b lymphocytes of both spleen and bursal origin to ibdv infection. the infected cells were metabolically-labelled and the viral polypeptides were analyzed by immunoprecipitation using monoclonal antibodies (mabs). virus adsorption and the effects of neutralizing c ...	1993	8263113
retroviral transformation in vitro of chicken t cells expressing either alpha/beta or gamma/delta t cell receptors by reticuloendotheliosis virus strain t.	exposure of normal juvenile chicken bone marrow cells to the replication defective avian reticuloendotheliosis virus strain t (rev-t) (chicken syncytial virus [csv]) in vitro resulted in the generation of transformed cell lines containing t cells. the transformed t cells derived from bone marrow included cells expressing either alpha/beta or gamma/delta t cell receptors (tcrs) in proportions roughly equivalent to the proportions of tcr-alpha/beta and tcr-gamma/delta t cells found in the normal b ...	1993	8382253
fowlpox virus recombinants expressing the envelope glycoprotein of an avian reticuloendotheliosis retrovirus induce neutralizing antibodies and reduce viremia in chickens.	eight stable fowlpox virus (fpv) recombinants which express the envelope glycoprotein of the spleen necrosis virus (snv) strain of reticuloendotheliosis virus (rev), an avian retrovirus, were constructed. these recombinants differ in the genomic location of the inserted genes, in the orientation of the insert relative to flanking viral sequences, and in the promoter used to drive expression of the env gene. of these variables, promoter strength seems to be the most crucial. the p7.5 promoter of ...	1993	8388488
antibody response elicited against empty reticuloendotheliosis virus particles in two inbred lines of chicken.	immunisation of houghton white leghorn line 15i and 6(1) chickens with empty reticuloendotheliosis virus particles elicited a primary antibody response which is probably directed against the viral envelope glycoproteins gp73/71 and gp22. antibodies in line 15i birds were shown to be non-neutralising and did not protect against the tumourigenic effects of reticuloendotheliosis virus, strain t. however, immunised line 6(1) chicks did not exhibit the runting syndrome associated with reticuloendothe ...	1993	8273276
the matrix region is responsible for the differential ability of two retroviruses to function as helpers for vector propagation.	we have investigated the ability of two related reticuloendotheliosis viruses to propagate a spleen necrosis virus (snv) based retroviral vector in canine osticosarcoma (d17) cells. reticuloendotheliosis virus strain a (rev-a) consistently propagated the vector more efficiently than snv in cell culture. to identify the area of the viral genome responsible for the superior helper function of rev-a, we constructed chimeric viruses between snv and rev-a. analysis of helper function indicated that a ...	1993	8421894
syngeneic lysis of reticuloendotheliosis virus-transformed cell lines transfected with marek's disease virus genes by virus-specific cytotoxic t cells.	cell-mediated immune responses against marek's disease virus (mdv) antigens were examined using reticuloendotheliosis virus (rev)-transformed cell lines of two haplotypes (b19b19 and b13b13). these cell lines were stably transfected with cloned fragments of mdv dna resulting in the expression of the mdv-specific phosphoprotein pp38. effector cells were obtained from p2a (b19b19) and s13 (b13b13) chickens at 7 days post inoculation with rev, oncogenic or attenuated serotype 1 mdv (jm-16/o and jm- ...	1994	7725630
characterization of a marek's disease virus bamhi-l-specific cdna clone obtained from a marek's disease lymphoblastoid cell line.	two marek's disease (md) virus bamhi-l-specific cdna clones were isolated from a cdna library constructed from poly(a)+ rna fractions of an md lymphoblastoid cell line, mdcc-cu41 (cu41). these clones were mapped to the region corresponding to the bamhi-q2 and l-regions. these clones hybridized with 2.5-, 0.8-, and 0.6-kb transcripts prepared from cu41. the transcriptional unit of the 0.6-kb transcript was determined by rnase protection assays. an open reading frame encoding a 107-amino-acid poly ...	1994	8289349
v-rel induces expression of three avian immunoregulatory surface receptors more efficiently than c-rel.	the c-rel gene is a member of nf-kappa b/rel family of transcription factors that regulate expression of a variety of immunoregulatory molecules. the viral oncogene, v-rel, is a truncated and mutated form of the turkey c-rel gene expressed by reticuloendotheliosis virus, strain t. in this study, we demonstrated that three avian immunoregulatory receptors, major histocompatibility (mhc) antigens class i and class ii as well as the interleukin-2 receptor (il-2r), were induced on the surface of spl ...	1994	8254742
a serosurvey using enzyme-linked immunosorbent assay for antibodies against poultry pathogens in ostriches (struthio camelus) from zimbabwe.	horseradish peroxidase-conjugated goat anti-ostrich igg was raised and used in commercial enzyme-linked immunosorbent assay kits to detect antibodies reactive with 11 poultry pathogens in sera from 149 ostriches from nine farms around zimbabwe. antibodies were detected to turkey rhinotracheitis virus (99%), newcastle disease virus (23%), avian reovirus (19%), infectious bursal disease virus (15%), avian encephalomyelitis virus (15%), mycoplasma gallisepticum and/or m. synoviae (11%), reticuloend ...	1994	7832718
diseases and management of backyard chicken flocks in chitungwiza, zimbabwe.	to gather information on backyard chicken flocks in chitungwiza, an urban center in zimbabwe, 85 flock owners were interviewed. the mean flock size was 53 birds (range 1-650), and most birds were kept for meat, for either domestic consumption or local sale. mean age at slaughter was 12.4 weeks (range 8-24). none of the owners vaccinated their birds, and reported mortality rates were high (mean 25%), most commonly being associated with diseases causing eye and respiratory problems. most owners co ...	1994	7832719
identification of latency-associated transcripts that map antisense to the icp4 homolog gene of marek's disease virus.	two small rnas (0.9 and 0.75 kb), named marek's disease virus (mdv) small rnas (msrs) and a 10-kb rna, all of which map antisense to the mdv icp4 homolog gene, have been readily detected in mdcc-msb1 mdv-transformed t-lymphoblastoid cells. these rnas were not detectable in reticuloendotheliosis virus-transformed t cells. when mdv was reactivated by treatment of lymphoblastoid cells with 25 micrograms of iododeoxyuridine per ml, the relative levels of the transcripts decreased. these rnas were no ...	1994	8083968
an immunoperoxidase plaque assay for reticuloendotheliosis virus and its application to a sensitive serum neutralization assay.	a rapid assay for the enumeration of reticuloendotheliosis virus (rev) is described. chicken embryo fibroblast monolayer cultures were infected with rev and incubated 6 days under an agar overlay. after removal of the overlay, cells were fixed with acetone/ethanol. foci of infection (hereafter referred to as plaques) were detected using either an anti-rev envelope monoclonal antibody or convalescent chicken serum as the primary antibody; the secondary antibody was either horseradish peroxidase-c ...	1994	8002888
uses of flow cytometry in virology.	this article reviews some of the published applications of flow cytometry for in vitro and in vivo detection and enumeration of virus-infected cells. sample preparation, fixation, and permeabilization techniques for a number of virus-cell systems are evaluated. the use of flow cytometry for multiparameter analysis of virus-cell interactions for simian virus 40, herpes simplex viruses, human cytomegalovirus, and human immunodeficiency virus and its use for determining the effect of antiviral comp ...	1994	7530594
pseudotyped rev/srv retroviruses reveal restrictions to infection and host range within members of the same receptor interference group.	the reticuloendotheliosis virus (rev) group of retroviruses and type d simian retroviruses (srv) belong to the same receptor interference group. the cellular receptor for these viruses has not yet been identified. in order to study the distribution of the receptor and to identify a receptor negative cell line, vector viral pseudotypes between rev and srv were made. using these viral pseudotypes, susceptibility to infection was examined in some rodent and marsupial cell lines. infectivity assays ...	1994	7975230
cell-mediated immune effector functions in chickens.	cell-mediated immune responses form an important part of the protection against intracellular pathogens. the mhc class i and class ii antigens are important for the proper presentation of degraded proteins to cytotoxic t lymphocytes (ctl) and helper t cells, respectively. recent developments in the knowledge of the molecular structure of the mhc in relation to antigen presentation are discussed. although ctl are important, there is a paucity of information concerning their relevance for the cont ...	1994	7937468
poultry oncogenic retroviruses and humans.	viruses of the avian leukosis/sarcoma group (alsv) and reticuloendotheliosis viruses (rev) are highly prevalent in chickens and turkeys and naturally cause tumors in them. commercial chickens are positive for antibodies, and a proportion actually carry infectious virus. virus may be present in chicken products and in eggs, thus human exposure is virtually universal. the viruses show little potential for producing infectious viral particles in mammalian cells; nevertheless, they have the capacity ...	1994	8162609
in vivo evolution of c-rel oncogenic potential.	the c-rel proto-oncogene belongs to the nf-kappa b/rel and i kappa b gene families, which regulate several inducible processes, including self-defense/repair and embryogenesis. transduction of the c-rel transcription factor by the avian retrovirus resulted in the formation of a highly oncogenic virus, reticuloendotheliosis virus strain t (rev-t), that encodes the oncogene v-rel. to examine the oncogenic potential of c-rel, we inserted it into a rev-t-based retroviral vector, rescued virus [rev-c ...	1994	8139023
thymocyte apoptosis induced by elevated endogenous corticosterone levels.	a well-known model of apoptosis is induction in thymocytes by injection of pharmacological doses of exogenous steroids. the aim of this study was to investigate whether this process also occurs under physiological conditions, i.e. by stimulation of endogenous glucocorticoid release, using the chicken as an experimental model. endogenous glucocorticoid levels can be elevated by immunization with exogenous antigens or by injection of conditioned medium, e.g. supernatant of mitogen-stimulated splee ...	1994	8181522
structural genes, not the ltrs, are the primary determinants of reticuloendotheliosis virus a-induced runting and bursal atrophy.	reticuloendotheliosis virus strain a (rev-a) and chicken syncytial virus (csv), two replication competent avian retroviruses, differ in the extent to which they induce a runting syndrome that includes anemia, lymphoid organ atrophy, and reduced body size. we have isolated an infectious clone of csv, the less pathogenic of the two viruses, and compared it to rev-a. partial dna sequence analysis suggests that it differs from rev-a by no more than 1 to 2% at the nucleotide level. analysis of viral ...	1994	8009826
integration of multiple chicken retroviruses into multiple chicken herpesviruses: herpesviral gd as a common target of integration.	integration of two different avian retroviruses, reticuloendotheliosis virus (rev) and avian leukosis virus (alv), into the genome of two different avian herpesviruses, the herpesvirus of turkeys (hvt) and marek's disease virus (mdv), was investigated. integration events occurred by the fourth and sixth in vitro passage of cells coinfected with rev/hvt and alv/mdv, respectively. in order to further characterize the integration events, integrated proviruses and surrounding herpesviral genetic mat ...	1994	8030268
a double hairpin structure is necessary for the efficient encapsidation of spleen necrosis virus retroviral rna.	we conducted a mutational analysis within the previously defined encapsidation sequence (e) for spleen necrosis virus (snv), an avian retrovirus. we found that two regions are necessary for efficient snv replication. the first region is a double hairpin structure as proposed by konings et al. (1992, j. virol., 66, 632-640); the second region is located downstream of the hairpins. we showed further that the double hairpin structure is required for efficient snv rna encapsidation. our work is the ...	1994	8313915
mapping of receptor binding domains in the envelope protein of spleen necrosis virus.	spleen necrosis virus (snv) is an amphotropic retrovirus originally isolated from a duck. although of avian origin, it also replicates on some mammalian cells. snv-derived retroviral vectors work with high efficiency and have a high potential for various gene transfer applications. however, little is known about the envelope-receptor interactions of this virus. we constructed a series of recombinant envelope proteins to characterize the su peptide of snv. we found that, in contrast to the envelo ...	1995	7769695
the v-rel oncoprotein complexes with new rel- and rela-related proteins in transformed cells.	the v-rel oncoprotein of the rev-t retrovirus interacts with a number of cellular proteins in transformed chicken spleen cells including p40/i kappa b alpha, p68c-rel, hsc70, and the p124 and p115 precursors for the p50 and p52 subunits of nf kappa b. here we report that v-rel associates with at least three other cellular proteins of 75-85 kda in these cells, as well as with a protein related to human rela. western blot analysis of v-rel immune complexes showed cross-reactivity between all of th ...	1995	7886940
detection of antibodies to avian leukosis/sarcoma viruses and reticuloendotheliosis viruses in humans by western blot assay.	serologic evidence of antibodies in humans to avian leukosis/sarcoma viruses (alsv) and reticuloendotheliosis viruses (rev) has in general been negative. because of the difficulty in infecting mammalian cells in vitro with these viruses, it is generally held that they do not infect humans. we first provided presumptive evidence of serologic response to these viruses in human sera of workers in poultry slaughtering plants, using an elisa. we now provide confirmatory evidence using western blot as ...	1995	8925516
structure and regulation of the gene encoding avian inhibitor of nuclear factor kappa b-alpha.	the rel/nf-kappa b family of transcription factors exist in the cytoplasm as inactive complexes in association with an inhibitory protein called i kappa b-alpha. we have isolated a clone containing the avian i kappa b-alpha gene from a chicken genomic library. avian i kappa b-alpha is devoid of any recognizable promoter elements, i.e., tata and caat boxes; however, the 5'-utr of the gene contains the initiator elements frequently found in tata-less genes. avian i kappa b-alpha contains seven put ...	1995	8543172
rrr-alpha-tocopheryl succinate inhibits dna synthesis and enhances the production and secretion of biologically active transforming growth factor-beta by avian retrovirus-transformed lymphoid cells.	the rrr-alpha-tocopheryl succinate form of vitamin e, referred to as vitamin e succinate (ves), inhibits the proliferation of avian reticuloendotheliosis virus-transformed recc-utc4-1 (c4-1) lymphoblastoid cells in a dose-dependent manner in vitro. analyses of conditioned medium (cm) from ves growth-inhibited cells revealed a potent antiproliferative activity. characterization of the antiproliferative activity as transforming growth factor-beta (tgf-beta) was established by 1) growth inhibition ...	1995	8584453
[effect of internal sequences in the moloney murine leukemia virus genome on replication].	construction and using of retrovirus vectors derived from the moloney murine leukemia virus (momulv) are described. these vectors, designated minimal vectors, contain the left and right long terminal repeats (ltrs), a binding site for proline trna, a polypurine tract (ppt), and a dominant marker for selective introduction of vectors into a packaging cell line, but lack the internal sequences of the virus genome. the experiments showed that the minimal vectors can be replicated and that their tit ...	1995	8666218
use of the polymerase chain reaction for the diagnosis of natural infection of chickens and turkeys with marek's disease virus and reticuloendotheliosis virus.	marek's disease (md) is a highly contagious lymphoproliferative disease of chickens caused by a herpesvirus, while reticuloendotheliosis (rev) virus is an avian c-type retrovirus that causes bursal and nonbursal lymphomas which often closely resemble mdv lymphomas. to provide a rapid and sensitive means of diagnosing and differentiating between these two neoplastic conditions, we have applied the pcr. the primers chosen to detect mdv sequences flank the 132 bp tandem repeat of the bamhi-h fragme ...	1995	18645767
reticuloendotheliosis viruses and derived vectors.	in most human gene therapy trials, the tools of gene delivery are retroviral vectors. all current vectors are derived from murine leukemia virus (mlv). although this system is suitable for delivering a large variety of genes into different tissues, it also has its limitations and is not adequate for all potential applications of human gene therapy. thus, attempts are underway in many laboratories to develop other gene delivery tools. potential agents range from non-viral based gene delivery syst ...	1995	7671105
detection of antibodies to avian leukosis/sarcoma viruses (alsv) and reticuloendotheliosis viruses (rev) in humans by elisa.	we used a modified commercial elisa kit to test for antibodies to avian leukosis/sarcoma and reticuloendotheliosis viral antigens in the sera of 45 poultry workers and their matched controls. we found that 42% of sera from poultry workers had anti-avian leukosis sarcoma viruses (anti-alsv) and 20% had anti-reticuloendotheliosis viruses (anti-rev), antibody titers that were higher than the highest titer recorded in control subjects, and hence were regarded as positive. to determine the specificit ...	1995	7585725
mutations in the dna-binding and dimerization domains of v-rel are responsible for altered kappa b dna-binding complexes in transformed cells.	the c-rel proto-oncogene encodes a member of the rel/nf-kappa b family of transcription factors. the oncogenic viral form, v-rel, transduced by avian reticuloendotheliosis virus t, induces lymphoid tumors. v-rel transformation may be mediated directly by binding of v-rel to cognate dna sites, resulting in altered gene expression, and/or indirectly by releasing rel/nf-kappa b transcription factors from cytoplasmic retention molecules, resulting in their translocation to the nucleus and the inappr ...	1995	7745683
mutations of conserved cysteine residues in the cwlc motif of the oncoretrovirus su protein affect maturation and translocation.	the envelope glycoprotein complex is composed of two polypeptides, an external heavily glycosylated polypeptide (su) and a membrane-spanning protein (tm). together they form a heterodimer on the surface of the virion. these proteins are synthesized in the form of a polyprotein precursor which is glycosylated and proteolytically processed during its maturation in the secretory pathway. a highly conserved stretch of four amino acids, cwlc, has been identified in most known oncoretroviral su protei ...	1995	7856101
an outbreak of lymphomas in commercial broiler breeder chickens vaccinated with a fowlpox vaccine contaminated with reticuloendotheliosis virus.	gross and microscopic examinations of affected tissues from chickens of two commercial broiler breeder flocks aged 27 and 31 weeks revealed lesions of visceral lymphomas with bursal involvement in some chickens. reticuloendotheliosis virus (rev), but not avian leukosis virus (alv), was isolated from blood of affected chickens. furthermore, dna extracted from tumours tested positive for rev, but not for alv or marek's disease virus by polymerase chain reaction (pcr) test. attempts to determine th ...	1996	18645835
enhancement of reticuloendotheliosis virus-induced bursal lymphomas by serotype 2 marek's disease virus.	the effect of serotype 2 and 3 marek's disease virus (mdv) vaccines on the pathogenesis of reticuloendotheliosis virus (rev)-induced bursal and non-bursal lymphomas was examined in chickens of rprl lines 15i(5) x 7(1) and 6(3) x 0, respectively. at hatch, chickens were vaccinated with strain 301b/1 of serotype 2 mdv or strain fc126 of turkey herpesvirus (hvt), a serotype 3 mdv and inoculated with spleen necrosis virus (snv), a non-defective strain of rev. in another experiment, bursas from 14-we ...	1996	18645839
the v-rel oncogene promotes malignant t-cell leukemia/lymphoma in transgenic mice.	the oncogene product from the avian reticuloendotheliosis virus strain t, v-rel, is a member of the rel/ nf-kappa b family of transcription factors. the mechanism by which v-rel induces oncogenic transformation remains unclear. several attempts to transform mammalian cells with v-rel have failed, suggesting that v-rel transformation may be a species-specific event. however, here we demonstrate that v-rel, but not a truncated c-rel, expressed under the control of the lck promoter, efficiently ind ...	1996	8670867
retroviral insertional activation in a herpesvirus: transcriptional activation of us genes by an integrated long terminal repeat in a marek's disease virus clone.	insertional activation of host proto-oncogenes has been recognized as a basic mechanism by which nonacute retroviruses induce cancer. our previous work has demonstrated that retroviruses can efficiently integrate into dna virus genomes. specifically, coinfection of cultured fibroblasts with a chicken herpesvirus, marek's disease virus (mdv), and a chicken retrovirus results in frequent stable retroviral insertions into the herpesvirus genome. such insertions could alter the expression of herpesv ...	1996	8642673
selective activation of the proto-oncogene c-jun promoter by the transforming protein v-rel.	the transcription factor v-rel is a transforming protein of the reticuloendotheliosis virus. we found that v-rel activates the promoter of the proto-oncogene c-jun. two elements in the c-jun promoter were required for the activation by v-rel. one was a kb-site (v-rel binding site), and the other was a c-jun promoter region between -52 and +148 (c-jun promoter (-52/+148)). two promoters with the kb-site(s), those of human immunodeficiency virus (hiv) and sv40, were not activated by v-rel, but the ...	1996	8668346
the immunodominant proteins of reticuloendotheliosis virus.	the antigenic profiles of three rev prototype strains, csv, snv and rev-t and eight israeli isolates were analysed by sds-page and immunoblotting with convalescent chicken serum, three mabs, 11a25, 11c237 and 11c100, a rabbit antiserum to rev-t whole virus (cui et al., 1986) and a rabbit antiserum to rev-a p30 gag protein (tsai et al., 1985). under both reducing (+dtt) and non-reducing conditions of sds-page, a major immunodominant 75-100 kda band was shared by all strains examined. in contrast ...	1996	8734645
marek's disease virus (mdv) icp4, pp38, and meq genes are involved in the maintenance of transformation of mdcc-msb1 mdv-transformed lymphoblastoid cells.	an antisense strategy has been used to identify genes important for the maintenance of transformation of mdcc-msb1 (msb1) marek's disease virus-transformed lymphoblastoid cells. oligodeoxynucleotides antisense to the predicted translation initiation regions of icp4 and pp38 mrnas inhibited proliferation of msb1 cells but not mdcc-cu91 (cu91) reticuloendotheliosis virus-transformed cells. control oligodeoxynucleotides having the same base composition but a different sequence did not inhibit msb1 ...	1996	8551572
syngeneic marek's disease virus (mdv)-specific cell-mediated immune responses against immediate early, late, and unique mdv proteins.	marek's disease (md) infection has been controlled effectively by vaccination using nononcogenic and/or attenuated oncogenic marek's disease virus (mdv) vaccines. thus far, there is little knowledge on the role of cell-mediated immune (cmi) responses during mdv infection or vaccination. to elucidate the importance of mdv proteins in cmi responses, the pp38, meq, icp4, or icp22 genes of an oncogenic strain, ga and the gb, orf a, a41, or l1 genes of a highly oncogenic strain, rb1b were stably tran ...	1996	8806490
reverse transcriptase activity in vaccines derived from chick cells.		1996	8978928
a non-radioactive method for identifying enzyme-amplified products of the reticuloendotheliosis proviral env and ltr genes using psoralen-biotin labelled probes.	a novel polymerase chain reaction (pcr) system based on the env gene of reticuloendotheliosis virus (rev) strain rev-a for the detection of proviral dna is described. the designed pcr product of 807 bp was identified using an internal probe of 278 bp produced by nested pcr from rev-infected dna cef. the env-gene pcr was then compared with the previously described pcr for proviral rev-long terminal repeat and the pcr product served also as the probe. the probes were labelled with the psoralen-bio ...	1996	8793837
lymphoid leukosis viruses, their recognition as 'persistent' viruses and comparisons with certain other retroviruses of veterinary importance.	diseases caused by lymphoid leukosis virus (llv), a retrovirus, take a long time after infection to develop and have a wide variety of pathological manifestations. this long latent period is characteristic of 'persistent virus infections'. disease produced by llv infection and its underlying mechanisms is compared with 'persistent' infections caused by other retroviruses in birds and mammals of veterinary importance. the diseases considered for comparison are those caused by reticuloendotheliosi ...	1996	8693704
use of the polymerase chain reaction for the detection of reticuloendotheliosis virus in marek's disease vaccines and chicken tissues.	reticuloendotheliosis virus (rev) proviral dna appears to be a frequent contaminant in marek's disease (md) vaccines. a polymerase chain reaction (pcr) was established and evaluated for its ability to detect rev proviral dna in infected cell cultures and chicken tissues. deoxynucleotide primers were selected from the highly conserved gag region of the rev genome. the amplification products were identified by electrophoresis, nested pcr and by hybridization with a digoxigenine-labelled oligonucle ...	1996	8693845
detection of contamination of vaccines with the reticuloendotheliosis virus by reverse transcriptase polymerase chain reaction (rt-pcr).	the reverse transcriptase polymerase chain reaction (rt-pcr) was applied to detect contamination of marek's disease (md) vaccine with reticuloendotheliosis virus (rev). the env primers were used for the 1st rt-pcr to amplify the dna fragments of rev-a and -t. the rel and env primers were used for nested-pcr to confirm the sites deleted from rev-t and rev-a. specific amplification products were detected in the 1st rt-pcr with these primers. by nested pcr with the env and the rel primer pairs, the ...	1996	8725107
oncogenic retroviruses of cattle, chickens and turkeys: potential infectivity and oncogenicity for humans.	reticuloendotheliosis virus naturally infects and cause lymphoid leukosis in chickens and turkeys. we investigated whether it can infect/transfect a variety of human cells in vitro. successful infection and transfection were achieved with limited replication of virus. these findings, together with the knowledge that other oncogenic retroviruses of chickens and cattle, viz. the avian leukosis/sarcoma viruses and bovine leukemia virus show similar infectivity/oncogencity in vitro for humans, and t ...	1996	8733164
rrr-alpha-tocopheryl succinate induces apoptosis in avian retrovirus-transformed lymphoid cells.	the rrr-alpha-tocopheryl succinate form of vitamin e [vitamin e succinate (ves)] inhibits the proliferation of avian reticuloendotheliosis virus-transformed recc-utc4-1 (c4-1) lymphoblastoid cells in a dose-dependent manner, blocks the cells in the g2/m cell cycle phase, and induces the cells to undergo apoptosis. apoptosis was documented by demonstrating changes that are characteristic of this type of cell death, including morphological analyses of chromatin condensation by 4',6-diamidine-2'-ph ...	1996	8837858
reduction of type v collagen using a dominant-negative strategy alters the regulation of fibrillogenesis and results in the loss of corneal-specific fibril morphology.	a number of factors have been implicated in the regulation of tissue-specific collagen fibril diameter. previous data suggest that assembly of heterotypic fibrils composed of two different fibrillar collagens represents a general mechanism regulating fibril diameter. specifically, we hypothesize that type v collagen is required for the assembly of the small diameter fibrils observed in the cornea. to test this, we used a dominant-negative retroviral strategy to decrease the levels of type v coll ...	1996	8947562
some observations on naturally occurring neoplasms of domestic fowls in the state of victoria, australia (1977-87).	in the 10 years to november 1987, 33 different types of naturally occurring neoplasms were diagnosed in 2281 domestic fowls submitted for necropsy examination. the most prevalent type was lymphoma (1825/2281 = 80%) including two cases in chickens from a flock free from marek's disease virus, exogenous avian leukosis viruses and reticuloendotheliosis virus; the remaining lymphomas were diagnosed on gross and/or histological criteria as marek's disease (1069) or lymphoid leukosis (754). of the non ...	1996	18645870
replication of non-defective reticuloendotheliosis viruses in the avian embryo assayed by pcr and immunofluorescence.	congenital transmission of reticuloendotheliosis virus (rev) is known to occur when one of the parents in either tolerantly infected or viraemic; however little attention has been paid to replication of the virus within the embryo itself. in this study five non-defective and one replication-defective strain of rev were inoculated into the yolk sac of 6-day-old embryonated eggs. with the exception of one non-defective strain, the others induced embryonic deformation or lesions that were apparent ...	1997	18483929
characterization of an internal ribosomal entry segment within the 5' leader of avian reticuloendotheliosis virus type a rna and development of novel mlv-rev-based retroviral vectors.	the murine leukemia virus (mlv)-related type c viruses constitute a major class of retroviruses that includes numerous endogenous and exogenous mammalian viruses and the related avian spleen necrosis virus (snv). the mlv-related viruses possess a long and multifunctional 5' untranslated leader involved in key steps of the viral life cycle--splicing, translation, rna dimerization, encapsidation, and reverse transcription. recent studies have shown that the 5' leader of friend murine leukemia viru ...	1997	9382952
avian retroviruses.	avian leukosis virus (alv) and reticuloendotheliosis virus (rev) are the most common naturally occurring avian retroviruses associated with neoplastic disease conditions in domesticated poultry. avian leukosis virus infects primarily chickens, whereas rev infects chickens, turkeys, and other avian species. in addition to causing tumors, both alv and rev can reduce productivity and induce immunosuppression and other production problems in affected flocks.	1997	9071747
retroviral insertional mutagenesis of a herpesvirus: a marek's disease virus mutant attenuated for oncogenicity but not for immunosuppression or in vivo replication.	our earlier studies have shown that retrovirus insertion into herpesvirus is an efficient process that engenders recombinant herpesviruses with altered biological properties. the rm1 clone is derived from the jm strain of marek's disease virus (mdv) through retrovirus insertional mutagenesis and contains sequences of reticuloendotheliosis virus inserted at the junction of the internal repeat and unique short regions of the genome. in previous studies, the rm1 clone appeared attenuated for oncoge ...	1997	9201407
differences in kappab dna-binding properties of v-rel and c-rel are the result of oncogenic mutations in three distinct functional regions of the rel protein.	the oncogene v-rel of reticuloendotheliosis virus, strain t, is derived from an avian c-rel proto-oncogene. c-rel encodes a member of the rel/nf-kappab family of transcription factors. the highly oncogenic v-rel differs from c-rel which has low transforming potential by the acquisition of numerous mutations. in this manuscript, we demonstrate that the oncogenic mutations in v-rel directly alter the ability of this protein to bind to dna. electrophoretic mobility shift analysis with rel proteins ...	1997	9205096
the antiretrovirus drug 3'-azido-3'-deoxythymidine increases the retrovirus mutation rate.	it was previously observed that the nucleoside analog 5-azacytidine increased the spleen necrosis virus (snv) mutation rate 13-fold in one cycle of retrovirus replication (v. k. pathak and h. m. temin, j. virol. 66:3093-3100, 1992). based on this observation, we hypothesized that nucleoside analogs used as antiviral drugs may also increase retrovirus mutation rates. we sought to determine if 3'-azido-3'-deoxythymidine (azt), the primary treatment for human immunodeficiency virus type 1 (hiv-1) i ...	1997	9151812
characterization of marek's disease herpesvirus-specific cytotoxic t lymphocytes in chickens inoculated with a non-oncogenic vaccine strain of mdv.	previously we have reported that reticuloendotheliosis virus (rev)-transformed cell lines expressing marek's disease virus (mdv) genes pp38, meq or gb were lysed by syngeneic mdv-specific splenocytes from major histocompatibility complex (mhc):b9b19 and mhc:b1b21 chickens. in contrast, rev-transformed cell lines expressing the mdv gene icp4 were only lysed by syngeneic mdv-specific splenocytes from mhc:b21b21 chickens. in this study we report that this syngeneic cell-mediated immune response is ...	1997	9176112
avian tumor viruses: persistent and evolving pathogens.	most neoplasias of lymphoid and other hematopoietic cells in commercial poultry are caused by viruses which belong to one of four distinct groups. marek's disease virus (mdv) is an oncogenic herpesvirus. avian leukosis virus (alv), reticuloendotheliosis virus (rev) and lymphoproliferative disease virus (lpdv) are oncogenic retroviruses. each group is distinguished by nucleic acid type, molecular structure, antigenicity, epidemiology, host range and other characteristics. however, most of these v ...	1997	9276987
v-rel activates the proto-oncogene c-jun promoter: a correlation with its transforming activity.	v-rel is a transforming protein of the reticuloendotheliosis virus, and is a transcription factor regulating various cellular genes. we found that v-rel activates the promoter of the proto-oncogene c-jun in a transient transfection assay system. moreover, the expression of endogenous c-jun was augmented in cells expressing exogenous v-rel, but not c-rel. the transcriptional activities of v-rel to the tested promoters containing the kb-site are lower than that of c-rel, but that to the c-jun prom ...	1997	9209405
field and vaccine strains of fowlpox virus carry integrated sequences from the avian retrovirus, reticuloendotheliosis virus.	for baculoviruses and herpesviruses, integration of transposons or retroviruses into the virus genome has been documented. we report here that field and vaccine strains of fowlpox virus (fpv) carry integrated sequences from the avian retrovirus, reticuloendotheliosis virus (rev). using pcr and hybridization analysis we observed that vaccine and field strains of fpv carry rev sequences integrated into a previously uncharacterized region of the right 1/3 of the fpv genome. long-range pcr, hybridiz ...	1997	9281517
c-jun involvement in vitamin e succinate induced apoptosis of reticuloendotheliosis virus transformed avian lymphoid cells.	previous studies have shown that treatment of avian reticuloendotheliosis virus-transformed recc-utc4-1 (c4-1) lymphoblastoid cells with 10 microg/ml (18.8 microm) of rrr-alpha-tocopheryl succinate (vitamin e succinate, ves) for 3 days induced approximately 50% of the cells to undergo apoptosis. elevated and prolonged expression of c-jun mrna and protein was temporally correlated with ves-induced cell death. data presented in this paper show that the elevated and prolonged expression of c-jun me ...	1997	9244357