| the lymphoproliferative disease virus of turkeys represents a distinct class of avian type-c retrovirus. | the lymphoproliferative disease virus of turkeys (lpdv) is the etiological agent of a rapidly developing lymphoproliferative process in turkeys. to better understand the genetic relationships of lpdv to other retroviruses we determined the nucleotide sequence of its pol gene. comparative computer analyses of the deduced amino acid sequences of the reverse transcriptase and integrase domains within pol established that lpdv represents a distinct class of avian retroviruses that is most closely re ... | 1992 | 1283141 |
| an in-vivo infectivity assay for cloned retroviruses lacking a susceptible cell culture. | the lymphoproliferative disease virus (lpdv) of turkeys is the retroviral agent of etiology of a rapidly developing, naturally occurring, lymphoproliferative process. recently we have molecularly cloned the viral genome. the lack of a susceptible cell culture which can sustain lpdv replication hampered the analysis of the infectious capability of the cloned genome. based on the efficient in-vivo replication of lpdv we have developed a sensitive in-vivo approach aimed at establishing the infectio ... | 1990 | 1695221 |
| lymphoproliferative disease virus of turkeys: sequence analysis and transcriptional activity of the long terminal repeat. | the lymphoproliferative disease virus (lpdv) is the etiological agent of a lymphoproliferative disease that naturally occurs in turkeys. recently, we have cloned the lpdv provirus and established it as a replication-competent genome devoid of a viral oncogene [gak et al., j. virol. 63 (1989) 2877-2880]. this report presents the nucleotide sequence of its long terminal repeat (ltr) and establishes it as a potent transcriptional element. several features of the lpdv ltr were similar to those found ... | 1991 | 2022329 |
| detection of lymphoproliferative disease virus by an enzyme-linked immunosorbent assay. | hitherto, detection of lymphoproliferative disease virus (lpdv), a c-type retrovirus of turkeys, has proved difficult since no tissue culture or serological assay has been available. development of serological tests has been hampered by the problems of raising virus-specific antisera. an indirect enzyme-linked immunosorbent assay (elisa) is reported, using a viral antiserum raised with bromelain-digested virus. the assay specifically detected purified virus at a concentration of 250 ng/ml or gre ... | 1987 | 2448156 |
| molecular cloning of an oncogenic replication-competent virus that causes lymphoproliferative disease in turkeys. | the lymphoproliferative disease virus of turkeys was molecularly cloned, structurally mapped, and shown to represent a distinct class of retroviruses evolutionarily related to the avian leukemia-sarcoma virus group. the cloned provirus did not contain any known oncogene or other cellularly derived sequences and was established as a replication-competent oncogenic entity capable of inducing the disease in the absence of any associated transforming counterpart. | 1989 | 2542599 |
| iron, transferrin, and acid and alkaline phosphatase in healthy turkeys and in turkeys inoculated with the lymphoproliferative disease virus. | presented are data on iron-binding capacity determinations in the serum of turkeys infected with lymphoproliferative disease (lpd) virus and in healthy males and females (laying eggs and nonlaying) from a breeding flock. also presented are results of serum and tissue total acid and alkaline phosphatase determinations in turkey poults infected with lpd virus and their uninfected controls and of serum enzyme levels in healthy males and females from the breeding flock. there was no significant alte ... | 1985 | 2983299 |
| characterisation of lymphoproliferative disease virus of turkeys. structural polypeptides of the c-type particles. | lymphoproliferative disease virus of turkeys (lpdv), a c-type retrovirus, was shown to contain 3 major [32 kilodaltons (kd, p 32), 26 kd, 22/21 kd] and 2 minor (41 kd and 12 kd) polypeptides. preliminary evidence suggests a glycoprotein of 76 kd (gp 76) and a major doublet polypeptide of 13.5/13 kd to be also of viral origin. of these gp 76 was susceptible to bromelain action implying its surface location in the virion, while p 32, p 26 and p 13.5/13 were the main constituents of viral cores. p ... | 1987 | 3038051 |
| analysis of structural polypeptides of the lymphoproliferative disease virus (lpdv) of turkeys. | the polypeptide composition of the lymphoproliferative disease virus (lpdv) of turkeys was shown to comprise several polypeptides with apparent molecular weights of 76, 31, 28, 20 and 15 kda. this polypeptide pattern is distinctly different from the protein profiles of avian leukosis viruses, reticuloendotheliosis virus, or murine leukemia viruses. moreover, lpd virions contain 2 major structural proteins (p31 and p28), in contrast to only one major internal protein present in most other retrovi ... | 1986 | 3510987 |
| effect of lymphoproliferative disease virus and of niridazole on the in vitro blastogenic response of peripheral blood lymphocytes of turkeys. | turkeys inoculated at 5 weeks of age with lymphoproliferative disease (lpd) virus developed typical lesions in the spleen, thymus, and pancreas. the in vitro blastogenic response of peripheral blood lymphocytes to the mitogens phytohemagglutinin and concanavalin a was drastically (up to 90%) suppressed in the inoculated turkeys 1 to 4 weeks postinoculation compared with uninoculated controls, and even at 11 weeks the response was about 50% inhibited. a lethal (about ld33) dose of antihelminthic ... | 1983 | 6197055 |
| organotropism of the lymphoproliferative disease virus (lpdv) of turkeys. | turkey poults were inoculated with lymphoproliferative disease virus (lpdv) of turkey, and the organotropism of the inoculated virus was determined from the kinetics of virus expression and tumor formation. molecular hybridization experiments, conducted to determine the level of viral rna expression in the various organs of infected birds, established lymphoid tissues, including bone marrow, as the target for lpdv infection. of these, bone marrow was the first to be infected but subsequently vir ... | 1982 | 6284660 |
| genetic control of the organ specificity of lymphoproliferative disease virus (lpdv) of turkeys. | in a previous study based on the kinetics of virus replication and tumor formation (gazit et al., 1982), it was shown that the organotropism of lymphoproliferative disease virus (lpdv) is confined to lymphoid tissues. the present paper demonstrates that this organ specificity is controlled at the level of infection and integration, that is, the lymphoid organs, which are the only organs sustaining virus replication, and also the only organs in whose cells integrated lpdv proviruses are detectabl ... | 1983 | 6298129 |
| identification of sequences in the long terminal repeat of the lymphoproliferative disease virus required for efficient transcription. | we analyzed the long terminal repeat (ltr) of the lymphoproliferative disease virus of turkeys for sequences that influence its promoter activity by using the chloramphenicol acetyltransferase assay. a series of ltr deletion mutants and recombinants between ltr and simian virus 40 regulatory sequences were used for these studies. through transfection experiments, we identified a negative regulatory element residing at the 5' end of the u3. the two imperfect direct repeats (drs) located at nt - 1 ... | 1995 | 7747452 |
| genome organization of a biologically active molecular clone of the lymphoproliferative disease virus of turkeys. | the lymphoproliferative disease retrovirus (lpdv) induces an acute, horizontally transmitted disease of turkeys that is often fatal. although lpdv cannot be grown in cultured cells, it was possible to isolate molecular clones of biologically active integrated proviral genomes from spleens of infected turkeys. based upon molecular hybridization and nucleotide sequence comparisons of its pol gene, lpdv was shown to represent a distinct group of avian retroviruses most closely related to avian sarc ... | 1994 | 7941337 |
| diagnostic test for lymphoproliferative disease virus infection of turkeys, using the polymerase chain reaction. | lymphoproliferative disease virus, a type-c retrovirus, is the etiologic agent of a naturally acquired lymphoproliferative disorder in turkeys. the disease is characterized by rapid induction of lymphoproliferative lesions with morphologic and histopathologic features resembling those of reticuloendotheliosis. owing to lack of overt clinical manifestations, early detection of lymphoproliferative disease virus is essential for preventing the rapid horizontal spread of the disease that can decimat ... | 1994 | 7944012 |
| 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 |
| retrovirus-induced disease in poultry. | three species of avian retrovirus cause disease in poultry: the avian leukosis/sarcoma virus (alsv), reticuloendotheliosis virus (rev), and lymphoproliferative disease virus (lpdv) of turkeys. the alsv can be classified as slowly transforming viruses, which lack a viral oncogene, and acutely transforming viruses, which possess a viral oncogene. slowly transforming viruses induce late onset leukoses of the b cell lymphoid, erythroid, and myeloid cell lineages, and other tumors, by viral promoter ... | 1998 | 9706091 |
| multiple infection of chickens and turkeys with avian oncogenic viruses: prevalence and molecular analysis. | the avian herpesvirus, marek's disease virus (mdv) and several retroviruses, reticuloendotheliosis virus (rev), avian leukosis virus (alv) (chickens) and lymphoproliferative disease virus (turkeys) are oncogenic and immunosuppressive agents. these viruses were detected either alone, or in various combinations in blood and tumor dnas of commercial birds using pcr. we present a 5-year retrospective study that included 207 chicken and 52 turkey flocks. of these, 32 chicken and 18 turkey flocks were ... | 1999 | 10696434 |
| diagnosis of lymphoproliferative disease virus infection of turkeys by an indirect immunofluorescence test. | an indirect immunofluorescence (iif) test for the detection of lympho-proliferative disease virus (lpdv) is described. results presented show that smears of buffy coat cells and frozen sections of spleen, but not thymus, form suitable test materials for a rapid and specific diagnosis of lpdv infection of turkeys. between 0.1 and 0.6% of buffy coat cells from infected birds were antigen positive, and spleens from 18/18 and thymuses from 11/18 birds respectively, tested 16 months after viral inocu ... | 1987 | 18766626 |
| production of virus-specific antisera to lymphoproliferative disease virus of turkeys. | lymphoproliferative disease virus, a recently isolated c-type retro-virus, cannot yet be cultured in cells in vitro and rarely induces a high titre virus-specific antiserum. however, after digestion of purified virus with bromelain and rebanding the treated virus in sucrose gradients bald virions devoid of the viral spike glycoprotein and up to 20 host proteins were found to induce a high level virus-specific antibody response in rabbits and chickens. | 1987 | 18766656 |
| susceptibility of domestic birds to lymphoproliferative disease virus (lpdv) of turkeys. | the susceptibility of domestic ducks, geese and chickens to infection with lymphoproliferative disease virus (lpdv) of turkeys was tested. infection with lpdv was assayed by measuring the particle-associated dna polymerase in plasma. ducks and geese were not susceptible to infection with this virus. chickens were susceptible to the infection with lpdv and some of the birds developed a persistent viraemia. six serial passages in chickens of viraemic plasma were achieved. lymphoproliferative gross ... | 1983 | 18766786 |
| comparative susceptibility of two turkey strains to lymphoproliferative disease virus. | the susceptibility to lymphoproliferative disease (lpd) of 1-day-old and 3-week-old poults of two turkey strains (a and b) was examined. their susceptibility to infection with the causative virus was evaluated by the level and the duration of viraemia and by the presence of gross and microscopic lymphoproliferative lesions. although in field conditions the incidence of outbreaks of lpd in strain a turkeys was much higher than in strain b, both lines were found to be of similar susceptibility to ... | 1981 | 18770132 |